Artigos de revistas: "Acrylamide-Based polymers"

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Dragan, Stela, e Cristina Doina Vlad. "Functional polymers based on acrylamide crosslinked copolymers". Macromolecular Symposia 181, n.º 1 (maio de 2002): 47–56. http://dx.doi.org/10.1002/1521-3900(200205)181:1<47::aid-masy47>3.0.co;2-8.

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Hoffman, Allan S. "Environmentally Sensitive Polymers and Hydrogels". MRS Bulletin 16, n.º 9 (setembro de 1991): 42–46. http://dx.doi.org/10.1557/s0883769400056049.

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Environmentally sensitive polymers and hydrogels exhibit sharp changes in behavior in response to relatively small changes in conditions such as temperature or pH. Typical changes include precipitation of the polymer in water or collapse of a hydrogel with expulsion of a large fraction of the gel pore water. These changes are depicted in Figure 1. If such a polymer is grafted or adsorbed on another polymer surface or within the pores of a porous membrane, then one observes sharp changes in wettability or permeability, respectively, when the polymer is environmentally stimulated. These changes are usually reversible, although the recdissolution or reswelling processes are often slower than the precipitation or deswelling steps. Other examples of environmental stimuli and polymer system responses are listed in Tables I and II.A large number of polymers display sharp responses to such stimuli. Many are based on vinyl monomers, such as anionic and cationic monomers for pH, specificion, solvent, or electrically responsive systems, and N-alkyl substituted acrylamides (e.g., N-isopropyl acrylamide, or NIPAAm) for temperature-sensitive systems. Other copolymer compositions may contain the responsive moiety as a pendant group on one of the monomers. Photoresponsive groups have been incorporated in such a way.The ratio in the responsive polymer of the responsive monomeric component to the “nonresponsive” comonomer (e.g., the pH-sensitive monomer, acrylic acid, versus acrylamide or the temperature-sensitive monomer, NIPAAm versus acrylamide) will control both the sharpness and intensity of the response as well as the specific environmental conditions where it begins.

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Kolouchová, Kristýna, e Ondřej Groborz. "Multiresponsive Polymer Tracers for ¹⁹F MRI Based on Poly[N-(2,2-difluoroethyl) Acrylamide]". Chemické listy 116, n.º 3 (15 de março de 2022): 180–86. http://dx.doi.org/10.54779/chl20220180.

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Polymers with lower critical solution temperature (LCST) are molecularly soluble in their solutions at low temperatures but, when heated above their cloud point temperature, these polymers assemble into supramolecular particles or macroscopic precipitates. These particles or precipitated polymeric depots can be used for diagnostics, targeted drug delivery, controlled drug release from a depot or a combination of diagnostics and therapy (theranostics). Herein, we describe smart polymer systems which contain N-(2,2-difluoroethyl)acrylamide monomer unit (DFEA) and form polymeric nanoparticles upon heating or precipitate after injection to polymeric implants/depots. Due to a high fluorine content and to relaxation properties of this element, these polymers are suitable as tracers for the 19F MRI method, a promising non-invasive diagnostic tool. Moreover, DFEA copolymers can contain monomers that react to additional physicochemical properties, resulting in multiresponsive polymers (pH- or redox-responsive), which can be used for smart drug delivery systems with controlled release of drugs in the target environment.

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Quan, Xie, Su e Feng. "The Thermoviscosifying Behavior of Water-Soluble Polymer Based on Graft Polymerization of Pluronic F127 with Acrylamide and 2-Acrylamido-2-methylpropane Sulfonic Acid Sodium Salt". Polymers 11, n.º 10 (16 de outubro de 2019): 1702. http://dx.doi.org/10.3390/polym11101702.

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A new concept of thermoviscosifying polymers is proposed to address the problems about decreasing viscosity of polymer solution under high temperatures. However, existing thermoviscosifying polymers have complicated synthesis processes and high costs, and both of them restrict the wide practical applications of thermoviscosifying polymers. Although polyethers have the characteristics of thermal gelatinization, they just display thermoviscosifying behaviors only under extremely high concentrations (>15 wt %). Therefore, the graft copolymerization of the commercialized Pluronic F127 (PEO100-PPO65-PEO100) with acrylamide and 2-acrylamide-methylpropionic acid sodium salt was studied here. A series of graft modified polyether polymers were prepared and it was expected to get thermoviscosifying polymers with high molecular weights and low association temperatures. Several factors on thermoviscosifying behaviors were investigated, such as polymerization condition, polymer concentration, hydrophilic monomer, molecular structure and molecular weight. It was also proven that the apparent viscosity of polymer solution is influenced by polymer concentration, molecular weight of polymer, and content of anion groups.

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Sari, Repita, Sri Mulijani e Meri Suhartini. "Improvement of PVA-Glucomanan-Acrylamide Hydrogel as Base Material of Immobilization". Jurnal Kimia Valensi 8, n.º 1 (10 de maio de 2022): 1–9. http://dx.doi.org/10.15408/jkv.v8i1.20332.

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Hydrogel products are currently widely used in various fields, one of which is agriculture. Most hydrogels are made of synthetic polymers because they have good absorption but are not biodegradable. Glucomannan is a natural polymer that is able to absorb large amounts of water and biodegradable but it is difficult to maintain water content. One method to improve the mechanical properties of hydrogels is by modifying the hydrogels through the formation of an interpenetrating network (IPN) between natural polymers and synthetic polymers. In this study, the IPN hydrogel based on polyvinyl alcohol and glucomannan and acrylamide as a crosslinker was made by combining freeze-thaw and gamma irradiation techniques. The results showed that the hydrogel water absorption after immersion for 24 hours was 311.09% where the weight of glucomannan was 1 g and acrylamide was 0.75 g and the irradiation dose was 30 kGy. The result of cumulative release test of paraquat immobilized into the hydrogel was 12.00% within 10 days. This indicates that the PVA-glucomannan-acrylamide hydrogel can be used as a controlled paraquat release matrix so as to minimize the effect on the overuse of pesticides.

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Gussenov, Iskander Sh, Alexey V. Shakhvorostov, Nurbatyr Mukhametgazy e Sarkyt E. Kudaibergenov. "Synthetic polyampholytes based on acrylamide derivatives – new polymer for enhanced oil recovery". Kazakhstan journal for oil & gas industry 4, n.º 4 (21 de janeiro de 2023): 104–16. http://dx.doi.org/10.54859/kjogi108622.

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Background: Due to its high efficiency, polymer flooding has been widely used in the fields of Kazakhstan. However, under conditions of high water salinity, high concentrations of polymers are needed to ensure the design viscosity of the solutions, therefore, polymers are needed that, at concentrations not exceeding 0.10.2%, will increase the viscosity of water up to 2050 cP when the formation water salinity is above 200 g/ l. Aim: The purpose of this work is to study the salt- and heat-resistant properties of a linear polyampholyte based on acrylamide, an anionic monomer sodium salt of 2-acrylamido-2-methyl-1-propanesulfonic acid - and a cationic monomer (3-acrylamidopropyl) trimethylammonium chloride and substantiate its applicability in oil production. Materials and methods: We used water with a salinity of 200300 g/l, as well as oils with viscosities of 60, 138, and 420 cP. To simulate a porous medium, bulk sand models and aerated concrete with high porosity were chosen. Hydrolyzed polyacrylamide with a molecular weight of 17 million Da and a ternary polyampholyte with a molecular weight of 2.9 million Da were used as polymers. To compare the effectiveness of these polymers under conditions of high salinity, experiments were carried out to measure the dynamic viscosity and oil displacement efficiency. Results: It is shown that the injection of a 0.25% solution of triple polyampholyte dissolved in water with a salinity of 200 g/l into sand models increases the oil displacement efficiency by 2328% compared to the injection of formation water. Under identical conditions, the injection of a hydrolyzed polyacrylamide solution resulted in an increase in the oil displacement efficiency by only 18%. Conclusion: Triple polyampholyte based on acrylamide derivatives has superior oil displacement properties compared to hydrolyzed polyacrylamide in high salinity reservoirs. The results of laboratory experiments can draw the attention of oil and gas industry specialists and subsoil users to new developments by the staff of the Institute of Polymer Materials and Technologies in terms of scaling up synthetic polyampholytes and conducting pilot tests.

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Nadtoka, O., O. Vashchenko e N. Kutsevol. "THERMAL PROPERTIES OF CROSS-LINKED POLYMERS BASED ON CHITOSAN AND POLYACRYLAMIDE". Polymer journal 45, n.º 3 (9 de setembro de 2023): 214–20. http://dx.doi.org/10.15407/polymerj.45.03.214.

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The thermal properties of cross-linked polymers based on chitosan and polyacrylamide were studied. Samples of the resulting network polymers, which included chains of polyacrylamide and chitosan, were obtained as hydrogel materials by radical polymerization of acrylamide in the presence of chitosan using the redox system of cerium (IV) ammonium nitrate as an initiator and N,N’-methylene-bis-acrylamide as a crosslinker. The structure of the obtained polymers was confirmed by comparing their IR spectra with the spectra of chitosan and polyacrylamide. It was shown that in the IR spectrum of the chitosan-containing sample, the peak at 2932 cm -1 indicates the presence of CH2 groups in the polymer chains and the formation of cross-links. Deformation and valence vibrations of the amide group in polyacrylamide are observed at 1600–1660 cm -1, and the band at 1633 and 1411 cm -1, which appears when the amide bond of polyacrylamide is formed, corresponds to C-N vibrations in the graft copolymer. These characteristic bands confirm the possibility of graft copolymerization of acrylamide on chitosan. The influence of the mass ratio of chitosan and polyacrylamide on the thermal properties of polymer systems was investigated by the method of thermogravimetric and differential thermogravimetric analysis. Atmospheric gas (1 bar, 40 % relative humidity) was used in all thermoanalytical measurements. The samples were examined after vacuum drying at 4 × 10-7 bar and 60 °C using Concentrator Plus. TGA and DTG curves were obtained in the temperature range from 30 to 500 °C with a scanning speed of 5 °C/min using 40 μl aluminum oxide crucibles. It was established that increasing the concentration of chitosan during synthesis reduces the amount of bound water in the obtained samples. Analysis of thermal destruction at the final stages of heating indicates that the presence of chitosan in samples of cross-linked polymers increases their heat resistance by 10–15 °C. The obtained regularities can be used in the creation of composite materials for hydrogel wound dressings and covering medical agents for external use.

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Mahmood, Arshad, Alia Erum, Sophia Mumtaz, Ume Ruqia Tulain, Nadia Shamshad Malik e Mohammed S. Alqahtani. "Preliminary Investigation of Linum usitatissimum Mucilage-Based Hydrogel as Possible Substitute to Synthetic Polymer-Based Hydrogels for Sustained Release Oral Drug Delivery". Gels 8, n.º 3 (9 de março de 2022): 170. http://dx.doi.org/10.3390/gels8030170.

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The aim of this study was to investigate the potential of Linum usitatissimum mucilage, a natural polymer, in developing a sustained release hydrogel for orally delivered drugs that require frequent dosing. For this purpose, nicorandil (a model drug)-loaded hydrogels with various feed ratios of Linum usitatissimum mucilage, acrylamide (monomer) and methylene bis-acrylamide (crosslinker) were prepared. The newly synthesized hydrogel formulations were probed fundamentally with respect to swelling behaviour, solvent penetration, and the release of the drug from the hydrogels. Later, the selected formulations were further characterized by Fourier-transform infrared spectroscopy, thermal analysis, X-ray diffraction analysis, and scanning electron microscopy. The swelling coefficient demonstrated a linear relation with the polymer ratio; however, an inverse behaviour in the case of monomer and crosslinker was observed. The drug release studies, performed at pH 1.2 and 4.5 and considering the dynamic environment of GIT, demonstrated that all formulations followed the Korsmeyer–Peppas model, displaying a slow drug release via diffusion and polymer erosion. FTIR analysis confirmed the successful grafting of acrylamide on linseed mucilage. Furthermore, scanning electron microscopy revealed a clear surface morphology with folds and pinholes in the hydrogel. Therefore, based upon the in-vitro outcomes, it can be concluded that a promising sustained release hydrogel can be prepared from natural polymer, Linum usitatissimum mucilage, offering many-fold benefits over the conventional synthetic polymers for oral delivery of drugs.

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Wang, Heng, Shifeng Xu, Jia Ma, Zhaoyang Wang e Enzhu Hou. "Investigation of high thickness holographic gratings in acrylamide-based photopolymer". Modern Physics Letters B 30, n.º 32n33 (30 de novembro de 2016): 1650382. http://dx.doi.org/10.1142/s0217984916503826.

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We studied the holographic characteristics of acrylamide-based photopolymer layers ranging in thickness from 300 [Formula: see text] to 1000 [Formula: see text]. Scattering patterns of various materials were presented, and both transmittance and scattering ratio were measured. Then, theoretical and experimental Bragg selectivity curves of two samples with thicknesses of 300 [Formula: see text] and 510 [Formula: see text] were analyzed, demonstrating the effective optical thickness inside photopolymer, which was responsible for the width of Bragg selectivity curve. Through the simulation for the spatial dynamics of refractive index distribution inside materials with different thicknesses, the attenuation of grating along the direction of thickness inside photopolymer was presented. Moreover, the photo-induced polymer chain length was evaluated, and a growing tendency of polymer chain length as increasing depth of material thickness was presented for the first time, in other words, there were polymers with longer chain length in deeper layer of material.

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Khan, Sarfaraz, Huaili Zheng, Qiang Sun, Yongzhi Liu, Hong Li, Wei Ding e Andrea Navarro. "Analysis of Influencing Factors for Leaching of Acrylamide Monomer from Polyacrylamide-Based Flocculants Used in the Treatment of Sludge Dewatering". Sensor Letters 18, n.º 2 (1 de fevereiro de 2020): 128–32. http://dx.doi.org/10.1166/sl.2020.4194.

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Acrylamide (AM) monomer is one of the harmful type substance, are commonly using to produce polyacrylamide (PAMs) flocculants for water treatment. Because of incomplete polymerization, the molecules of AM monomers also in exit marketable polymers. Therefore, discharge of AM from the usage of PAM based polymers flocculants in to environment. Currently study focus on, the AM leaching behaviour (emulsion and powder) polymer produced by two different production processes was studied with WTP sludge dewatering as the research object. The flocculants type's effects, Concentration of sludge and dosage on the discharge of AM residual monomer in sludge dewatering effluent were studied. The powder form flocculants results show, the regardless of the flocculants concentration and sludge concentration, the leaching concentration is not significant, but in the emulsion flocculants, the leaching concentration changes significantly. The Monomers of residual acrylamide be absorbed on the surface of sludge. Sludge concentration plays an active role in improving dehydration efficiency. Considering the trade-off between emulsion and powder polymer, the results of this study are related to the water treatment process.

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Yang, Jun, Tengfei Dong, Jingtian Yi e Guancheng Jiang. "Development of Multiple Crosslinked Polymers and Its Application in Synthetic-Based Drilling Fluids". Gels 10, n.º 2 (2 de fevereiro de 2024): 120. http://dx.doi.org/10.3390/gels10020120.

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This study addresses the performance challenges of Synthetic-Based Drilling Fluids (SBDF) in deep wells and high-temperature environments by engineering a novel multiple hydrogen-bonded crosslinked polymer, MBAH/nano-SiO2. Synthesized using methyl methacrylate (MMA), butyl methacrylate (BMA), acrylic acid (AA), N-hydroxyethyl acrylamide (HEAA), and nano-silica (nano-SiO2), the polymer improved crosslinking density, thermal properties, particle size distribution, and colloidal stability. The development of a ‘weak gel’ structure in W/O emulsions improved rheology and electrical stability (ES), with ES values reaching up to 775 V after aging at 180 °C. Moreover, the polymer’s amphiphilic structure and the synergistic effect of nano-SiO2 increased emulsion film thickness and strength, further augmenting stability. The high-temperature and high-pressure filtration loss of SBDF was considerably reduced to 7.6 mL, benefiting well wall stability and reservoir damage control. This study provides crucial insights into optimizing multiple hydrogen-bonded crosslinked strategies and polymers in SBDF applications.

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Umerzakova, M. B., R. M. Iskakov, R. B. Sarieva, Zh N. Kainarbayeva e A. A. Espenbetov. "COMPOSITE MATERIALS BASED ON ALICYCLIC COPOLYIMIDE AND ACRYLIC ACID COPOLYMER WITH ACRYLAMIDE". Chemical Journal of Kazakhstan, n.º 3 (15 de setembro de 2023): 15–27. http://dx.doi.org/10.51580/2023-3.2710-1185.24.

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Progress in polymer materials science is mainly associated with the development of new composite materials, created by the introduction of modifying additives into the matrix polymer which which improve polymer characteristics due to their properties. The purpose of this work is to obtain composite materials with improved thermal and mechanical properties from copolyimide based on dianhydrides of tricyclotetracarboxylic and diphenyloxydtetracarboxylic acids with diaminodiphenyl ether modified by a copolymer of acrylic acid with acrylamide. Results and discussion. Polymer compositions of copolyimides of arylalycyclic structure in combination with acrylic acid copolymer and acrylamide, as well as composite materials (film) based on them, were obtained. It was found that with an increase in the content of the added component from 0.35 to 2.0 wt%, uniformity is maintained in the polymer mixture. The infrared (IR) spectroscopy method shows that during formation of the above polymer mixtures the interaction of functional groups of the polymers under study with the formation of hydrogen bonds, which determine the homogeneity of the mixture. By methods of thermogravimetry and stretching of the sample with a constant deformation rate were used to determine, respectively, the thermal resistance and mechanical properties of the developed composite films. The increase of thermal resistance and strength of the film is explained by the formation of partial intermolecular cross-linking between the components of the mixture and the elasticity of the material – with the plasticizing effect of the additive. Conclusion. Polymer mixtures were obtained and composite films were molded on their basis.

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Hennig, Kathleen, e Wolfdietrich Meyer. "Synthesis and Characterization of Catechol-Containing Polyacrylamides with Adhesive Properties". Molecules 27, n.º 13 (23 de junho de 2022): 4027. http://dx.doi.org/10.3390/molecules27134027.

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In this study, a row of four analogous dopamine acryl- and methacrylamide derivatives, namely N-(3,4-dihydroxyphenyethyl) acrylamide, N-(3,4-dihydroxyphenyethyl) meth acrylamide, N-phenethyl methacrylamide, N-(4-hydroxyphenethyl) methacrylamide were synthesized and characterized by 1H-NMR and 13C-NMR, followed by further solvent-based radical polymerization with N-hydroxyethyl acrylamide. All copolymers were characterized by 1H-NMR, dynamic differential calorimetry, and gel permeation chromatography. The dependency of the used comonomer ratios to the molecular mass of the corresponding copolymers has been described. The synthesis of the various polymers serves as a feasibility study and provides important data for a future biometric application in the medical field. We synthesized N-(3,4-dihydroxyphenyethyl) acrylamide copolymer up to 80 mol% by free radical polymerization without using any protecting groups. All polymers show identical perfect adhesive properties by a simple scratch test. Further, the monomers were used as a photo reactive glue formulation to test its adherence to a medical titanium surface sample by tensile shear test.

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Sudhakar, Dr K., Leo Amalraj, V. Lakshmi Tejaswini, N. Mourya Sree, P. Divya Harshitha e M. Rubika Julie. "Eco-friendly Biodegradable Super Absorbent Polymers (SAPs); An Effective Water Retainer and Agrofertilizer". Alinteri Journal of Agriculture Sciences 36, n.º 1 (29 de junho de 2021): 753–56. http://dx.doi.org/10.47059/alinteri/v36i1/ajas21105.

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A polymer is a material which consists of very large molecules, or macromolecules, composed of many repeating subunits. They are classified as synthetic and natural polymers both play essential roles in everyday life due to their broad spectrum of properties. The foremost important class of polymers is superabsorbent polymer (SAP) materials. They are hydrophilic networks which absorb and retain large amounts of water. SAPs are originally divided into two main classes. They are Synthetic (Petrochemical based) and Natural (e.g.; Polysaccharide and Polypeptide based). Most of the present superabsorbent polymers are frequently produced from acrylic acid and acrylamide solution or inverse-suspension polymerization techniques. These are not biodegradable and are harmful to the environment that causes pollution. So, we sought to make biodegradable SAP that can act as a fertilizer to improve the soil quality and water conservation in agricultural land.

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Ge, Qi, Zhe Chen, Jianxiang Cheng, Biao Zhang, Yuan-Fang Zhang, Honggeng Li, Xiangnan He et al. "3D printing of highly stretchable hydrogel with diverse UV curable polymers". Science Advances 7, n.º 2 (janeiro de 2021): eaba4261. http://dx.doi.org/10.1126/sciadv.aba4261.

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Hydrogel-polymer hybrids have been widely used for various applications such as biomedical devices and flexible electronics. However, the current technologies constrain the geometries of hydrogel-polymer hybrid to laminates consisting of hydrogel with silicone rubbers. This greatly limits functionality and performance of hydrogel-polymer–based devices and machines. Here, we report a simple yet versatile multimaterial 3D printing approach to fabricate complex hybrid 3D structures consisting of highly stretchable and high–water content acrylamide-PEGDA (AP) hydrogels covalently bonded with diverse UV curable polymers. The hybrid structures are printed on a self-built DLP-based multimaterial 3D printer. We realize covalent bonding between AP hydrogel and other polymers through incomplete polymerization of AP hydrogel initiated by the water-soluble photoinitiator TPO nanoparticles. We demonstrate a few applications taking advantage of this approach. The proposed approach paves a new way to realize multifunctional soft devices and machines by bonding hydrogel with other polymers in 3D forms.

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Cody, Dervil, Alan Casey, Izabela Naydenova e Emilia Mihaylova. "A Comparative Cytotoxic Evaluation of Acrylamide and Diacetone Acrylamide to Investigate Their Suitability for Holographic Photopolymer Formulations". International Journal of Polymer Science 2013 (2013): 1–6. http://dx.doi.org/10.1155/2013/564319.

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The comparative cytotoxic evaluation of two monomers, diacetone acrylamide (DA) and acrylamide (AA) used in holographic photopolymer formulations, is reported. Two normal cell lines were used: BEAS-2B and HaCaT. Cellular viability was assessed using the MTT assay for three different exposure times. A difference of two orders of magnitude is observed in the lethal dose (LD50) concentrations of the two monomers. Diacetone acrylamide exhibits a significantly lower toxicity profile in comparison to acrylamide at all exposure times. This result justifies the replacement of acrylamide with diacetone acrylamide in the photopolymer formulation, with the view to reducing occupational hazard risks for large-scale holographic device fabrication. A comparative study investigating the holographic recording ability of the two photopolymers in transmission mode showed that the DA photopolymer is capable of reaching refractive index modulation values of3.3×10-3, which is 80% of the refractive index modulation achieved by the AA photopolymer. This makes the DA-based photopolymers suitable for a wide range of applications.

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Lei, Lei, Qi Zhang, Shuxian Shi e Shiping Zhu. "Oxygen-switchable thermo-responsive random copolymers". Polymer Chemistry 7, n.º 34 (2016): 5456–62. http://dx.doi.org/10.1039/c6py01145d.

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In this paper, we report the synthesis of oxygen (O₂)-switchable thermo-responsive random copolymers based on fluorinated acrylamide monomer homologues: N-(2-fluoroethyl)acrylamide (F1EA), N-(2,2-difluoroethyl)acrylamide (F2EA), and N-(2,2,2-trifluoroethyl)acrylamide (F3EA).

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Onishi, Hayato, Yuta Koda e Hideo Horibe. "Thermoresponsive Conductivity of Acrylamide-based Polymers and Ni Microparticle Composites". Chemistry Letters 49, n.º 10 (5 de outubro de 2020): 1224–27. http://dx.doi.org/10.1246/cl.200342.

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Chen, Jiawen, Jun Ye, Mingming Zhang e Jian Xiong. "A Fast and Easy Probe Based on CMC/Eu (Ⅲ) Nanocomposites to Detect Acrylamide in Different Food Simulants Migrating from Food-Contacting Paper Materials". Polymers 14, n.º 17 (30 de agosto de 2022): 3578. http://dx.doi.org/10.3390/polym14173578.

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The residual acrylamide in food paper packaging can be transferred into water and food, which will cause harmful effects on human beings. In this paper, a rapid and easily available fluorescent probe based on carboxymethyl cellulose (CMC)/Eu (Ⅲ) nanocomposites was designed to detect the residue acrylamide with high sensibility. The probe could respond in 1 min. The concentration of acrylamide was linearly correlated to the fluorescence intensity of the probe at the emission wavelength of 615 nm in the concentration range of 0.1–100 μmol/L. The limit of detection (LOD) of the probe was 0.085 μg/L, which is lower than the guideline value of the European Union, the U.S. EPA, and the WHO. An experiment was performed to simulate the acrylamide migrating from food-contacting paper materials to different foods, including waterborne food, alcohol beverage, acidic food, and greasy food. The recoveries and RSDs of acrylamide in all samples indicated that the CMC/Eu (Ⅲ) fluorescent probe was efficient for acrylamide detection. The possible mechanism of the probe for acrylamide detection involved both dynamically quenching and static quenching by forming of non-fluorescent substances.

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Wang, Ren, Jie Yang, Luman Liu, Jianlong Wang, Zhenbo Feng, Die Zhang, Shan Gao, Jiao Wang, Han Ren e Baotong Hui. "Investigation on Filtration Control of Zwitterionic Polymer AADN in High Temperature High Pressure Water-Based Drilling Fluids". Gels 8, n.º 12 (14 de dezembro de 2022): 826. http://dx.doi.org/10.3390/gels8120826.

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With the exploration and development of high-temperature and high-salt deep oil and gas, more rigorous requirements are warranted for the performance of water-based drilling fluids (WBDFs). In this study, acrylamide, 2-acrylamide-2-methylpropanesulfonic acid, diallyl dimethyl ammonium chloride, and N-vinylpyrrolidone were synthesized by free radical copolymerization in an aqueous solution to form a temperature and salt-resistant zwitterionic polymer gel filtration loss reducer (AADN). The zwitterionic polymer had excellent adsorption and hydration groups, which could effectively combine with bentonite through hydrogen bonds and electrostatic attraction, strengthening the hydration film thickness on the surface of bentonite, and promoting the stable dispersion of drilling fluid. In addition, the reverse polyelectrolyte effect of zwitterionic polymers strengthened the drilling fluid’s ability to resist high-temperature and high-salt. The AADN-based drilling fluid showed excellent rheological and filtration control properties (FLAPI < 8 mL, FLHTHP < 29.6 mL) even after aging at high-temperature (200 °C) and high-salt (20 wt% NaCl) conditions. This study provides a new strategy for simultaneously improving the high-temperature and high-salt tolerance of WBDFs, presenting the potential for application in drilling in high-temperature and high-salt deep formations.

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Wang, Dan, Zhan Qian Song, Shi Bin Shang, Zhan Jun Wang e Myoung Ku Lee. "Preparation and Characterization of Kenaf-Based Superabsorbent Polymers". Advanced Materials Research 183-185 (janeiro de 2011): 1812–16. http://dx.doi.org/10.4028/www.scientific.net/amr.183-185.1812.

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Novel kenaf-based superabsorbent polymers (SAPs) were prepared by grafting acrylic acid (AA) and acrylamide (AM) onto kenaf cellulose. Graft copolymerization was carried out in aqueous solution using N, N’-methylenebisacrylamide (NMBA) as crosslinking agent and sodium bisulfite (NaHSO3) and ammonium persulfate ((NH4)2S2O8) as initiator. The SAPs so obtained were examined by SEM. The absorbency of SAPs consists of different kenaf cellulose in deionized water, saline solutions and different pH value solutions were investigated.

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EL-Sharif, Hazim F., Daniel M. Hawkins, Derek Stevenson e Subrayal M. Reddy. "Determination of protein binding affinities within hydrogel-based molecularly imprinted polymers (HydroMIPs)". Phys. Chem. Chem. Phys. 16, n.º 29 (2014): 15483–89. http://dx.doi.org/10.1039/c4cp01798f.

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Selective synthetic MIP recognition of a range of bio-significant proteins. Comparison of functional acrylamide-based polymer hydrogels as MIPs. MIP–protein dissociation constants within the micro-molar range. AFM measurements exhibited specific MIP interactions with cognate protein.

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Li, Jian, Jinsheng Sun, Kaihe Lv, Yuxi Ji, Jintao Ji e Jingping Liu. "Nano-Modified Polymer Gels as Temperature- and Salt-Resistant Fluid-Loss Additive for Water-Based Drilling Fluids". Gels 8, n.º 9 (29 de agosto de 2022): 547. http://dx.doi.org/10.3390/gels8090547.

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With the continuous exploration and development of oil and gas resources to deep formations, the key treatment agents of water-based drilling fluids face severe challenges from high temperatures and salinity, and the development of high temperature and salt resistance filtration reducers has always been the focus of research in the field of oilfield chemistry. In this study, a nano-silica-modified co-polymer (NS-ANAD) gel was synthesized by using acrylamide, isopropylacrylamide, 2-acrylamide-2-methyl propane sulfonic acid, diallyl dimethyl ammonium chloride, and double-bond-modified inorganic silica particles (KH570-SiO2) through free radical co-polymerization. The introduction of nanotechnology enhances the polymer’s resistance to high temperature degradation, making it useful as a high-temperature-resistant fluid loss reducer. Moreover, the anions (sulfonates) and cations (quaternary ammonium) enhance the extension of the polymer and the adsorption on the surface of bentonite particles in a saline environment, which in turn improves the salt resistance of the polymer. The drilling fluids containing 2.0 wt% NS-ANAD co-polymer gels still show excellent rheological and filtration performance, even after aging in high temperature (200 °C) and high salinity (saturated salt) environments, showing great potential for application in deep and ultra-deep drilling engineering.

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Yamamoto, Sachio, Shoko Yano, Mitsuhiro Kinoshita e Shigeo Suzuki. "In Situ Pinpoint Photopolymerization of Phos-Tag Polyacrylamide Gel in Poly(dimethylsiloxane)/Glass Microchip for Specific Entrapment, Derivatization, and Separation of Phosphorylated Compounds". Gels 7, n.º 4 (16 de dezembro de 2021): 268. http://dx.doi.org/10.3390/gels7040268.

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An improved method for the online preconcentration, derivatization, and separation of phosphorylated compounds was developed based on the affinity of a Phos-tag acrylamide gel formed at the intersection of a polydimethylsiloxane/glass multichannel microfluidic chip toward these compounds. The acrylamide solution comprised Phos-tag acrylamide, acrylamide, and N,N-methylene-bis-acrylamide, while 2,2′-azobis[2-methyl-N-(2-hydroxyethyl)propionamide] was used as a photocatalytic initiator. The Phos-tag acrylamide gel was formed around the channel crossing point via irradiation with a 365 nm LED laser. The phosphorylated peptides were specifically concentrated in the Phos-tag acrylamide gel by applying a voltage across the gel plug. After entrapment of the phosphorylated compounds in the Phos-tag acrylamide gel, 5-(4,6-dichlorotriazinyl)aminofluorescein (DTAF) was introduced to the gel for online derivatization of the concentrated phosphorylated compounds. The online derivatized DTAF-labeled phosphorylated compounds were eluted by delivering a complex of phosphate ions and ethylenediamine tetraacetic acid as the separation buffer. This method enabled sensitive analysis of the phosphorylated peptides.

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El-Rehim, H. A. Abd. "Fast Swelling and Superabsorbent Properties of Radiation Crosslinked Acrylamide Based Polymers". International Journal of Polymeric Materials 55, n.º 3 (março de 2006): 161–74. http://dx.doi.org/10.1080/009140390916594.

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Craciun, Gabriela, e Elena Manaila and Daniel Ighigeanu. "New Type of Sodium Alginate-g-acrylamide Polyelectrolyte Obtained by Electron Beam Irradiation: Characterization and Study of Flocculation Efficacy and Heavy Metal Removal Capacity". Polymers 11, n.º 2 (1 de fevereiro de 2019): 234. http://dx.doi.org/10.3390/polym11020234.

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The goals of the paper were first the obtainment and characterization of sodium alginate-g-acrylamide polyelectrolytes by electron beam irradiation in the range of 0.5 to 2 kGy, and second, the evaluation of flocculation efficacy and heavy metal removal capacity from aqueous solutions of known concentrations. Based on sodium alginate concentration, two types of grafted polymers were obtained. Physical, chemical, and structural investigations were performed. Flocculation studies under different stirring conditions on 0.5, 0.1 and 0.2% kaolin suspension were done. The removal capacity of Cu2+ and Cr6+ ions was also investigated. The acrylamide grafting ratio on sodium alginate backbone was found up to 2000% for samples containing 1% sodium alginate and up to 500% for samples containing 2% sodium alginate. Transmittances between 98 and 100% were obtained using, in the flocculation studies, polyelectrolytes containing 2% sodium alginate in concentrations of 0.5 and 1 ppm on kaolin suspension of 0.1 wt %. The polymer concentration was found critical for kaolin suspension of 0.05 and 0.1 wt %. Polymers containing 1% sodium alginate were efficient in Cr6+ ion removal, while those containing 2% in Cu2+ ion removal.

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Gomes, Dias e Costa. "Static Light Scattering Monitoring and Kinetic Modeling of Polyacrylamide Hydrogel Synthesis". Processes 7, n.º 4 (24 de abril de 2019): 237. http://dx.doi.org/10.3390/pr7040237.

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A kinetic model describing aqueous acrylamide homopolymerization and copolymerization of acrylamide with methylene bisacrylamide, leading to hydrogel formation, is presented and applied in the simulation of these reaction processes. This modeling approach is based on population balances of generating functions and, besides the crosslinking mechanisms inherent to network formation, other specific kinetic steps important in acrylamide polymerization (e.g., branching due to backbiting) are considered in the simulation tool developed. The synthesis of acrylamide polymers and hydrogels was performed at 26 °C and at 40 °C using two different initiation systems. The formation of such materials was monitored using in-line static light scattering (SLS), and the spatial inhomogeneity of the final hydrogels was also measured using this experimental technique. It is shown that the simulations are helpful in describing information provided by SLS in-line monitoring, namely in the early stages of polymerization with the transition from dilute to semi-dilute regime. Indeed, it finds a plausible match between the critical overlap polymer concentration and gelation, this later leading to the observed spatial heterogeneity of the hydrogels. Usefulness of the kinetic model for defining operation conditions (initial composition, semi-batch feed policies, chain transfer, etc.) in making the shift from gelation to the semi-dilute regime is discussed, and the extension of this approach to processes enabling a higher control of gelation (e.g., controlled radical polymerization) is also prospected.

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Gao, Yulei, Xiang Di, Fenfen Wang e Pingchuan Sun. "Room temperature tunable multicolor phosphorescent polymers for humidity detection and information encryption". RSC Advances 12, n.º 13 (2022): 8145–53. http://dx.doi.org/10.1039/d2ra00294a.

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A polymer with tunable multicolor was prepared via copolymerizing a phosphor with concentration dependent luminescence and acrylamide based on chemical crosslinking and hydrogen bonding interactions for humidity detection and information encryption.

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Barabanova, Anna, Andrei Shibaev, Vyacheslav Molchanov, Olga Philippova e Alexei Khokhlov. "Preparation of Magnetic Fluids Based on Associated Polymers". Advanced Materials Research 650 (janeiro de 2013): 314–19. http://dx.doi.org/10.4028/www.scientific.net/amr.650.314.

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This paper describes two methods of preparation of magnetic fluids based on associated polymers. The first method is ultrasonic (US) dispersing of magnetite microparticles (MP) in aqueous solutions of associated polymers such as hydrophobically modified polyacrylamides (HM PAAm) – terpolymers of acrylamide (AAm), sodium acrylate (SA) and N-dodecylacrylamide (DDAA). According to the second method the magnetic fluids were formed by addition of magnetic polymers, synthesized by means of a micellar copolymerization of AA, SA and DDAA in the presence of MP, into water. The investigation of the rheological properties has shown that magnetic fluids obtained can be reversibly transformed in physical gels in magnetic field (MF).

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Kohut, Ananiy, Stanislav Voronov, Zoriana Demchuk, Vasylyna Kirianchuk, Kyle Kingsley, Oleg Shevchuk, Sylvain Caillol e Andriy Voronov. "Non-Conventional Features of Plant Oil-Based Acrylic Monomers in Emulsion Polymerization". Molecules 25, n.º 13 (30 de junho de 2020): 2990. http://dx.doi.org/10.3390/molecules25132990.

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In recent years, polymer chemistry has experienced an intensive development of a new field regarding the synthesis of aliphatic and aromatic biobased monomers obtained from renewable plant sources. A one-step process for the synthesis of new vinyl monomers by the reaction of direct transesterification of plant oil triglycerides with N-(hydroxyethyl)acrylamide has been recently invented to yield plant oil-based monomers (POBMs). The features of the POBM chemical structure, containing both a polar (hydrophilic) fragment capable of electrostatic interactions, and hydrophobic acyl fatty acid moieties (C15-C17) capable of van der Waals interactions, ensures the participation of the POBMs fragments of polymers in intermolecular interactions before and during polymerization. The use of the POBMs with different unsaturations in copolymerization reactions with conventional vinyl monomers allows for obtaining copolymers with enhanced hydrophobicity, provides a mechanism of internal plasticization and control of crosslinking degree. Synthesized latexes and latex polymers are promising candidates for the formation of hydrophobic polymer coatings with controlled physical and mechanical properties through the targeted control of the content of different POBM units with different degrees of unsaturation in the latex polymers.

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Wu, Xiaohua, Zhen Zhang, Haiying Lu, Xiao Luo, Chengli Li e Qiang Li. "Preparation and Application of Environmentally-Friendly Copolymer Filtration Control Agent Based on Hydrogen Bonding". Journal of Physics: Conference Series 2679, n.º 1 (1 de janeiro de 2024): 012039. http://dx.doi.org/10.1088/1742-6596/2679/1/012039.

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Abstract Traditional water-based drilling fluids encounter challenges in terms of poor solubility in high-density water-based drilling fluids and difficulty in meeting biotoxicity standards when using heat-resistant polymers as filtration control agents. To address this issue, this study introduces MIL-100 (Fe)-NH2 type MOF due to its excellent catalytic activity, which activates industrial-grade large-sized lignosulfonate sodium. The particle size of lignosulfonate sodium is reduced from micrometer to nanometer scale, significantly enhancing its reactivity in polymerization reactions. The activated lignosulfonate sodium is then used as a raw material and reacted with acrylamide, 2-acrylamido-2-methylpropane sulfonic acid, and catechol to produce a novel polymer filtration control agent named PTASL. Biotoxicity tests demonstrate that both pre-aged and post-aged PTASL exhibit EC50 values exceeding 30,000 mg/L, indicating that they are environmentally friendly polymers with no biotoxic effects.

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Gao, Nanxiao, Jian Chen, Min Qiao, Guangcheng Shan, Jingzhi Wu e Qianping Ran. "Anionic Copolymers with Different Charge Densities for Regulating the Properties of Cement Pastes". Materials 15, n.º 21 (30 de outubro de 2022): 7629. http://dx.doi.org/10.3390/ma15217629.

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Self-compacting concrete (SCC) is an extremely flowable concrete, which increases the probability of segregation and bleeding. Viscosity-modifying admixtures (VMAs) have been developed to improve the stability of SCC. Synthetic polymer VMAs have excellent water solubility and stability, and can be easily chemically prepared and modified. In this work, a series of copolymers based on anionic 2-acrylamido-2-methyl-propanesulfonic acid (AMPS) and nonionic N, N-dimethyl acrylamide (DMAA), with similar molecular weights but different charge densities, were prepared. The effect of the charge density of the anionic polymers on the fluidity, rheological property, and adsorption behavior of the cement pastes was investigated. The action mechanism of the polymers was discussed. The results indicate that the charge density of anionic polymer VMAs is of great significance for the development of cost-effective SCCs with good rheological properties.

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Dei, Nanako, Kazuhiko Ishihara, Akikazu Matsumoto e Chie Kojima. "Preparation and Characterization of Acrylic and Methacrylic Phospholipid-Mimetic Polymer Hydrogels and Their Applications in Optical Tissue Clearing". Polymers 16, n.º 2 (15 de janeiro de 2024): 241. http://dx.doi.org/10.3390/polym16020241.

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The 2-methacryloyloxyethyl phosphorylcholine (MPC) polymers are mimetic to phospholipids, being widely used as biocompatible polymers. In our previous study, MPC polymer hydrogels proved more effective for optical tissue clearing compared to acrylamide (AAm) polymer hydrogels. In the present study, 2-acryloyloxyethyl phosphorylcholine (APC) was synthesized and employed to create hydrogels for a comparative analysis with methacrylic MPC-based hydrogels. APC, an acrylic monomer, was copolymerized with AAm in a similar reactivity. In contrast, MPC, as a methacrylic monomer, demonstrated higher copolymerization reactivity than AAm, leading to a spontaneously delayed two-step polymerization behavior. This suggests that the polymer sequences and network structures became heterogeneous when both methacrylic and acrylic monomers, as well as crosslinkers, were present in the copolymerization system. The molecular weight of the APC polymers was considerably smaller than that of the MPC polymers due to the formation of mid-chain radicals and subsequent β-scission during polymerization. The swelling ratios in water and strain sweep profiles of hydrogels prepared using acrylic and methacrylic compounds differed from those of hydrogels prepared using only acrylic compounds. This implies that copolymerization reactivity influences the polymer network structures and crosslinking density in addition to the copolymer composition. APC-based hydrogels are effective for the optical clearing of tumor tissues and are applicable to both passive and electrophoretic methods.

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Schechter, LeeAnn, Bruce K. Bernard, Frank W. Barvenik, John G. McNally, Marvin Friedman, Amy Essenfeld e Randy Deskin. "Evaluation of the Toxicological Risk Associated with the Use of Polyacrylamides in the Recovery of Nutrients from Food Processing Waste (I)". Journal of the American College of Toxicology 13, n.º 4 (agosto de 1994): 261–72. http://dx.doi.org/10.3109/10915819409140598.

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Trivalent metal ions such as iron and aluminum are currently employed to flocculate liquid-borne solids from food-processing waste streams. These captured nutrient-rich waste solids are disposed of mainly through land applications (e.g., subsoil injection) because of the potential toxicity associated with the metal salts. Low-toxicity, water-soluble polyacrylamide polymers are currently approved for and employed as flocculants in potable water applications. The use of these polymers in food-processing waste streams could enable the captured solids to be recycled as components of animal feed, thus decreasing the burden on landfills and making good use of the proteinaceous matrix. However, polyacrylamides contain very low concentrations of acryl-amide monomer, which is highly toxic and can cause neurotoxicity, cytogenic lesions, and an increase in tumor rates in experimental animals. With use of two industrial food processing wastes, experiments were conducted to determine how acrylamide monomer would partition during a solids/liquid separation and subsequent rendering. Based on the analytical data, 96% of the acrylamide monomer was measured in the water portion after separation. Because of background interferences, acrylamide could not be directly measured in the solids portion. With use of these results and worst-case calculations, <2 ppb of acrylamide could be present in animal feed, thereby making the associated risk de minimis.

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Baker, John P., David R. Stephens, Harvey W. Blanch e John M. Prausnitz. "Swelling equilibria for acrylamide-based polyampholyte hydrogels". Macromolecules 25, n.º 7 (março de 1992): 1955–58. http://dx.doi.org/10.1021/ma00033a019.

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Liang, Feng, Ghaithan Al-Muntasheri, Hooisweng Ow e Jason Cox. "Reduced-Polymer-Loading, High-Temperature Fracturing Fluids by Use of Nanocrosslinkers". SPE Journal 22, n.º 02 (5 de outubro de 2016): 622–31. http://dx.doi.org/10.2118/177469-pa.

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Summary In the quest to discover more natural-gas resources, considerable attention has been devoted to finding and extracting gas locked within tight formations with permeability in the nano- to microdarcy range. The main challenges associated with working in such formations are the intrinsically high-temperature and high-pressure bottom conditions. For formations with bottomhole temperatures at approximately 350–400°F, traditional hydraulic-fracturing fluids that use crosslinked polysaccharide gels, such as guar and its derivatives, are not suitable because of significant polymer breakdown in this temperature range. Fracturing fluids that can work at these temperatures require thermally stable synthetic polymers such as acrylamide-based polymers. However, such polymers have to be used at very-high concentrations to suspend proppants. The high-polymer concentrations make it very difficult to completely degrade at the end of a fracturing operation. As a consequence, formation damage by polymer residue can reduce formation conductivity to gas flow. This paper addresses the shortcomings of the current state-of-the-art high-temperature fracturing fluids and focuses on developing a less-damaging, high-temperature-stable fluid that can be used at temperatures up to 400°F. A laboratory study was conducted with this novel system, which comprises a synthetic acrylamide-based copolymer gelling agent and is capable of being crosslinked with an amine-containing polymer-coated nanosized particulate crosslinker (nanocrosslinker). The laboratory data have demonstrated that the temperature stability of the crosslinked fluid is much better than that of a similar fluid lacking the nanocrosslinker. The nanocrosslinker allows the novel fluid system to operate at significantly lower polymer concentrations (25–45 lbm/1,000 gal) compared with current commercial fluid systems (50–87 lbm/1,000 gal) designed for temperatures from 350 to 400°F. This paper presents results from rheological studies that demonstrate superior crosslinking performance and thermal stability in this temperature range. This fracturing-fluid system has sufficient proppant-carrying viscosity, and allows for efficient cleanup by use of an oxidizer-type breaker. Low polymer loading and little or no polymer residue are anticipated to facilitate efficient cleanup, reduced formation damage, better fluid conductivity, and enhanced production rates. Laboratory results from proppant-pack regained-conductivity tests are also presented.

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Jouenne, S., e B. Levache. "Universal viscosifying behavior of acrylamide-based polymers used in enhanced oil recovery". Journal of Rheology 64, n.º 5 (setembro de 2020): 1295–313. http://dx.doi.org/10.1122/8.0000063.

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Kenawy, El-Refaie. "Biologically active polymers: controlled-release formulations based on crosslinked acrylamide gel derivatives". Reactive and Functional Polymers 36, n.º 1 (fevereiro de 1998): 31–39. http://dx.doi.org/10.1016/s1381-5148(97)00095-3.

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Quoika, Patrick K., Maren Podewitz, Yin Wang, Anna S. Kamenik, Johannes R. Loeffler e Klaus R. Liedl. "Thermosensitive Hydration of Four Acrylamide-Based Polymers in Coil and Globule Conformations". Journal of Physical Chemistry B 124, n.º 43 (15 de outubro de 2020): 9745–56. http://dx.doi.org/10.1021/acs.jpcb.0c07232.

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Prasetyaningrum, Aji, Al Farrel A. Raemas, Nur Rokhati e Bakti Jos. "Application of Glyoxal Acrylamide Modified Κ-Carrageenan as A Superabsorbent Polymer in Drug Delivery System". Reaktor 20, n.º 3 (13 de outubro de 2020): 150–58. http://dx.doi.org/10.14710/reaktor.20.3.150-158.

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The hydrogel is superabsorbent polymers (SAP) that are biodegradable and can be obtained from polysaccharides, lipids, and proteins. Polysaccharides include cellulose, starch and their derivatives, seaweed extracts such as carrageenan, alginate, pectin, and chitosan. Carrageenan is the result of the extraction of red seaweed sap with an alkaline solution. The main objective of this study was to simultaneously increase the strength and properties of κ-carrageenan SAP film with the addition of glyoxal and acrylamide as crosslinkers. The addition of acrylamide (variated from 1 to 7 % b/v) into the k-Carrageenan based SAP hydrogel compound and the presence of glyoxal as crosslink agent (variated from 0 to 1,0 % v/v). The physical properties of the SAP films were analyze using swelling degree and tensile strength. The structural and morphological properties of composite films were analyzed using Fourier Transform Infrared (FTIR) and Scanning Electron Microscopy (SEM). In addition, the effect of pHs on the releasing drug Poly(vinylpyrrolidone)-Iodine was investigated. This research shows that the addition of acrylamide and glyoxal can improve the physical properties of the modified κ-carrageenan film. Characterization using SEM shows that the addition of glyoxal causes the formation of tissue fibers in SAP. FTIR spectra indicated the formation of cross bonds in modified SAP film at 3294.42 cm-1 (carboxylic acid). The treatment under alkaline conditions will increase drug release ability.Keywords: κ-carrageenan; hydrogels; acrylamide; glyoxal; drug delivery

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Su, Li Qiang, Ying Wang e Hong Tao Chu. "Chiral Separation of Amino Acid Derivatives by Molecular Imprinting Technique". Advanced Materials Research 239-242 (maio de 2011): 2545–48. http://dx.doi.org/10.4028/www.scientific.net/amr.239-242.2545.

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Molecularly imprinted polymers, based on the surface-modified silica gel, were prepared with silylanized silica gel as a carrier, acrylamide as functional monomer, ethylene dimethacrylate (EDMA) as crosslinker and Boc-L-phenylalanine as the template molecule. The results of HPLC shows that the imprinted polymers have good specific recognition of Boc-L-phenylalanine. The baseline separation of Boc-phenylalanine enantiomer was achieved in 20 min, the resolution was 1.84 and the maximum adsorption capacity was 6788 mg g-1.

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F. Abdullah1, Saja. "SYNTHESIS OF NEW LEVOFLOXACIN SELECTIVE MEMBRANE SENSOR BASED ON MOLECULARLY IMPRINTED POLYMERS." iraq journal of market research and consumer protection 13, n.º 1 (30 de junho de 2021): 95–107. http://dx.doi.org/10.28936/jmracpc13.1.2021.(10).

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Two molecular imprinted polymer (MIP) membranes for Levofloxacin (LEV) were prepared based on PVC matrix. The imprinted polymers were prepared by polymerization of styrene (STY) as monomer, N,N methylene di acrylamide as a cross linker ,benzoyl peroxide (BPO) as an initiator and levofloxacin as a template. Di methyl adepate (DMA) and acetophenone (AOPH) were used as plasticizers , the molecular imprinted membranes and the non molecular imprinted membranes were prepared. The slopes and detection limits of the liquid electrodes ranged from -21.96 – -19.38 mV/decade and 2×10-4M- 4×10-4M, and Its response time was around 1 minute, respectively. The liquid electrodes were packed with 0.1 M standard drug solution and its response were stable at pH ranges from 1.0 to 11.0 and with good selectivity for more than several type. The electrodes produced have been successfully applied in preparation of the pharmaceutical sample for the determination of the analyte without any time consuming pretreatment steps.

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Rychter, Piotr, Diana Rogacz, Kamila Lewicka, Jozef Kollár, Michał Kawalec e Jaroslav Mosnáček. "Ecotoxicological Properties of Tulipalin A-Based Superabsorbents versus Conventional Superabsorbent Hydrogels". Advances in Polymer Technology 2019 (3 de março de 2019): 1–15. http://dx.doi.org/10.1155/2019/2947152.

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The Phytotoxicological Aspects of a Novel Superabsorbent/Hydrogels: poly(acrylamide-co-sodium 4-hydroxy-2-methylenebutanoate), prepared from renewable monomer Tulipalin A, on the growth and development of monocotyledonous Avena sativa and dicotyledonous Raphanus sativus, was investigated and compared with the effect of borate-crosslinked poly(vinyl alcohol), poly(acrylamide), and poly(acrylamide-co-sodium acrylate) conventional hydrogels. Tulipalin A-based superabsorbent hydrogels revealed superior properties in terms of the combination of the tested properties. The results confirmed excellent suitability of Tulipalin A-based hydrogels for application as reservoirs of water during plant stress condition. Values of fresh matter (yield) and shoot height of the examined plants growing in soil amended with these hydrogels were ca 10% higher than those of plants growing in soil without hydrogels. Reference borate-crosslinked PVA hydrogels (containing increasing amount of borax cross-linker) revealed harmful effect on plants. The negative effect was observed on most of the investigated properties, increasing with content of the hydrogel in soil and concentration of the borax in it.

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Devasahayam, Sheila, M. Ameen, T. Verheyen e Sri Bandyopadhyay. "Brown Coal Dewatering Using Poly (Acrylamide-Co-Potassium Acrylic) Based Super Absorbent Polymers". Minerals 5, n.º 4 (30 de setembro de 2015): 623–36. http://dx.doi.org/10.3390/min5040512.

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Yokota, Shingo, Takefumi Ohta, Takuya Kitaoka e Hiroyuki Wariishi. "Adsorption of cellobiose-pendant polymers to a cellulose matrix determined by quartz crystal microbalance analysis". BioResources 4, n.º 3 (24 de junho de 2009): 1098–108. http://dx.doi.org/10.15376/biores.4.3.1098-1108.

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Cellobiose-pendant polymers were synthesized by radical polymerization and their affinity for a cellulose matrix was investigated by quartz crystal microbalance (QCM). A 2-(methacryloyloxy)ethylureido cellobiose (MOU-Cel) macromer was synthesized by coupling cellobiosylamine with 2-(methacryloyloxy)ethyl isocyanate followed by polymerization in an aqueous radical reaction system. The interaction of the resulting poly(MOU-Cel) with a pure cellulose matrix in water was evaluated by QCM analysis. Poly(MOU-Cel) was strongly adsorbed to the cellulose substrate, whereas neither cellobiose nor MOU-Cel macromer exhibited an attractive interaction with cellulose. This specific interaction was not inhibited by the presence of ionic contaminants, suggesting that multiple cellobiopyranose moieties in each polymer molecule might cooperatively enhance its affinity for cellulose. Moderate insertion of acrylamide units into the polymer backbone improved the affinity for cellulose, possibly due to an increased mobility of sugar side chains. Polymers such as these, with a high affinity for cellulose, have potential applications for the surface functionalization of cellulose-based materials, including paper products.

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Poliwoda, Anna, Małgorzata Mościpan e Piotr P. Wieczorek. "Application of Molecular Imprinted Polymers for Selective Solid Phase Extraction of Bisphenol A". Ecological Chemistry and Engineering S 23, n.º 4 (1 de dezembro de 2016): 651–64. http://dx.doi.org/10.1515/eces-2016-0046.

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Abstract Selective molecularly imprinted polymers (MIPs) with bisphenol A as template were synthesized using the non-covalent imprinting approach. MIPs were prepared using thermally initiated polymerization with 1,1’-azobis(cyclohexanecarbonitryle) (ACHN) as initiator and ethylene glycol dimethacrylate (EDMA) as a cross-linking agent. The tested functional monomers included methacrylic acid, acrylamide, and 4-vinylpyridine. The selectivity of the BPA-MIP for the solid phase extraction of bisphenol A was tested in samples containing other related alkylphenols. The polymers prepared in acetonitrile using methacrylic acid or acrylamide as monomer showed the highest selectivity towards target analyte (the selectivity ratio 8:1, respectively for MIP and NIP). The proposed procedure has been proven to be an effective for selective extraction of bisphenol A in aqueous samples (recoveries over 85%) enabling detection and quantification limits of 25 and 70 μg/dm3, respectively based on 10 cm3 of sample volume, with relative standard deviations (RSD) lower than 6%. The obtained molecularly imprinted material showed interesting properties for selective extraction and preconcentration of studied analyte from large volumes of aqueous samples without any problems of cartridge clogging.

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Braun, Olivier, Clément Coquery, Johann Kieffer, Frédéric Blondel, Cédrick Favero, Céline Besset, Julien Mesnager, François Voelker, Charlène Delorme e Dimitri Matioszek. "Spotlight on the Life Cycle of Acrylamide-Based Polymers Supporting Reductions in Environmental Footprint: Review and Recent Advances". Molecules 27, n.º 1 (22 de dezembro de 2021): 42. http://dx.doi.org/10.3390/molecules27010042.

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Humankind is facing a climate and energy crisis which demands global and prompt actions to minimize the negative impacts on the environment and on the lives of millions of people. Among all the disciplines which have an important role to play, chemistry has a chance to rethink the way molecules are made and find innovations to decrease the overall anthropic footprint on the environment. In this paper, we will provide a review of the existing knowledge but also recent advances on the manufacturing and end uses of acrylamide-based polymers following the “green chemistry” concept and 100 years after the revolutionary publication of Staudinger on macromolecules. After a review of raw material sourcing options (fossil derivatives vs. biobased), we will discuss the improvements in monomer manufacturing followed by a second part dealing with polymer manufacturing processes and the paths followed to reduce energy consumption and CO2 emissions. In the following section, we will see how the polyacrylamides help reduce the environmental footprint of end users in various fields such as agriculture or wastewater treatment and discuss in more detail the fate of these molecules in the environment by looking at the existing literature, the regulations in place and the procedures used to assess the overall biodegradability. In the last section, we will review macromolecular engineering principles which could help enhance the degradability of said polymers when they reach the end of their life cycle.

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Arrua, Ruben Dario, Daniel Serrano, Gustavo Pastrana, Miriam Strumia e Cecilia I. Alvarez Igarzabal. "Synthesis of macroporous polymer rods based on an acrylamide derivative monomer". Journal of Polymer Science Part A: Polymer Chemistry 44, n.º 22 (2006): 6616–23. http://dx.doi.org/10.1002/pola.21768.

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Wang, Y. F., T. M. Chen, A. Kuriu, Y. J. Li e T. Nakaya. "Studies on novel phosphatidylcholine-modified acrylamide-based hydrogels". Journal of Applied Polymer Science 64, n.º 7 (16 de maio de 1997): 1403–9. http://dx.doi.org/10.1002/(sici)1097-4628(19970516)64:7<1403::aid-app20>3.0.co;2-w.

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Distantina, Sperisa, Nurul Hidayatun, Shifa Annisa Nabila, Mujtahid Kaavessina e Fadilah Fadilah. "Effect of Acrylamide And Potassium Peroxodisulphate on The Quality of Bead Gel Based on Cassava Bagasse-Carrageenan Using Microwave Grafting Method". Equilibrium Journal of Chemical Engineering 6, n.º 2 (4 de janeiro de 2023): 135. http://dx.doi.org/10.20961/equilibrium.v6i2.68130.

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Hydrogels are widely used for drug delivery systems, immuno-chemotherapy applications, efficient use of water, preventing dry soil, and increasing soil infiltration. Generally, hydrogels are derived from synthetic polymers which is non-biodegradable and toxic. Cassava bagasse is an alternative cellulose to make hydrogels. The purpose of this research was to determine the effect of the amount of acrylamide and potassium peroxodisulphate (KPS) initiator on the quality of bead gel based on cassava bagasse-carrageenan. Chemical structure of the hydrogel was studied using FTIR spectroscopy. Cassava bagasse was immersed in a solution of n-hexane to separate the fat. Then, fat-free cassava bagasse was grafted with mass ratios of cassava and acrylamide 1:5, 1:10, and 1:15 in 110 mL water. The solution was added with a KPS initiator with weight variations (g) 0.04; 0.08; 0.12 then stirred 15 min. The solution was put in the microwave with 630 watts of irradiation for 450 s with the cooling cycle temperature maintained at 65-70<sup>o</sup>C. The aqueous of grafted polymer and carrageenan was injected into beaker glass that contained 1 cm of palm oil and mixture of 0.2 M CaCl<sub>2</sub> and 0.2 M KCl in an ice bath. Results showed that the highest average swelling capacity was found in the bead gel variation 1:15 with the number of initiators 0.04 g of 1797.95% at a time of 210 minutes of immersion. From FTIR spectrum, it was found that there was a success in grafting acrylamide into bagasse’s backbone using the microwave grafting method with KPS as initiator.

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