Journal articles: 'Polymer Melt Films'

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Enose, Arno A., Priya K. Dasan, H. Sivaramakrishnan, and Sanket M. Shah. "Formulation and Characterization of Solid Dispersion Prepared by Hot Melt Mixing: A Fast Screening Approach for Polymer Selection." Journal of Pharmaceutics 2014 (March 12, 2014): 1–13. http://dx.doi.org/10.1155/2014/105382.

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Solid dispersion is molecular dispersion of drug in a polymer matrix which leads to improved solubility and hence better bioavailability. Solvent evaporation technique was employed to prepare films of different combinations of polymers, plasticizer, and a modal drug sulindac to narrow down on a few polymer-plasticizer-sulindac combinations. The sulindac-polymer-plasticizer combination that was stable with good film forming properties was processed by hot melt mixing, a technique close to hot melt extrusion, to predict its behavior in a hot melt extrusion process. Hot melt mixing is not a substitute to hot melt extrusion but is an aid in predicting the formation of molecularly dispersed form of a given set of drug-polymer-plasticizer combination in a hot melt extrusion process. The formulations were characterized by advanced techniques like optical microscopy, differential scanning calorimetry, hot stage microscopy, dynamic vapor sorption, and X-ray diffraction. Subsequently, the best drug-polymer-plasticizer combination obtained by hot melt mixing was subjected to hot melt extrusion process to validate the usefulness of hot melt mixing as a predictive tool in hot melt extrusion process.

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Winey, K. I., A. Faldi, and R. J. Composto. "Morphology of polymer-polymer dewetting in thin films." Proceedings, annual meeting, Electron Microscopy Society of America 53 (August 13, 1995): 182–83. http://dx.doi.org/10.1017/s0424820100137288.

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Two or more thin polymer layers are frequently combined for industrial applications such as protective coatings, lubricants, packaging, and adhesives. One might refer to such multi-layered polymeric structures as planar nanocomposites. The use of multiple polymer thin films requires the control of spreading and dewetting of these films. Our studies have identified a number of important characteristics of the kinetics and morphology of polymer melt / polymer melt dewetting. Particularly noteworthy is our ability to distinguish the two polymer melts in a cross-sectional view. At 190°C a 200 nm film of polycarbonate (PC) was found to dewet a 200 nm film of poly(styrene-co-acrylonitrile) (SAN) which had been deposited onto a rigid substrate. An optical micrograph of an intermediate stage of polymer-polymer dewetting shows the characteristic features: a circular hole in the upper layer (light gray), a rim surrounding the hole, and a small dimple in the center of the hole (dark gray), Figure 1.

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Seemann, Ralf, Stephan Herminghaus, Chiara Neto, Stefan Schlagowski, Daniel Podzimek, Renate Konrad, Hubert Mantz, and Karin Jacobs. "Dynamics and structure formation in thin polymer melt films." Journal of Physics: Condensed Matter 17, no. 9 (February 19, 2005): S267—S290. http://dx.doi.org/10.1088/0953-8984/17/9/001.

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Barbosa, Renata, Tatianny Soares Alves, Dayanne Diniz Souza Morais, Laura Hecker Carvalho, and Osanildo Damião Pereira. "Preparation of Biodegradable Polymer Nanocomposites and Vermiculite Clay by Melt Intercalation Technique." Materials Science Forum 775-776 (January 2014): 357–62. http://dx.doi.org/10.4028/www.scientific.net/msf.775-776.357.

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The consumption of plastic products over the years has been producing large numbers of waste material, which accumulate by landfill generating considerable environmental problems. Among biodegradable polymers, there is the PHB (poly-3-hydroxybutyrate), which has attracted more attention once it is obtained from renewable sources. This study aimed to prepare biodegradable nanocomposites by melt intercalation of PHB polymer in the natural vermiculite clay, in the ratios of 1, 3 and 6 wt%. The nanocomposites were obtained in an internal mixer coupled to a torque rheometer by Haake-Blucher, operating at 170°C, 50 rpm for 10 minutes. The material was triturated and then films were molded by compression under the conditions: 3 tons at 170°C for 3 minutes. The films were characterized by X-ray diffraction (XRD) and Infrared (FTIR). These analyzes were used to evaluate the intercalation and / or exfoliation of nanocomposites. In general, results indicated changes in structure as a function of clay content employed in the systems of PHB / vermiculite.

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Didenko, Andrey, Danila Kuznetcov, Valentina Smirnova, Gleb Vaganov, Alexey Ivanov, Vladimir Yudin, and Vladislav Kudryavtsev. "The Co-Poly(Urethane-Imide) Heat Resistant Thermoplastic Elastomers." Nano Hybrids and Composites 34 (February 23, 2022): 23–28. http://dx.doi.org/10.4028/p-rcjpez.

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Co-Pоly (Urethane-Imide) s (CPUI) based on pоly (diethyleneglycol) adipate diol, tolylenediisocyanate, multinucleate dianhydrides and diamines were synthesized. The films and moldings from CPUI were processed and their mechanical characteristics were evaluated. Distinctions of specifications of the films formed from polymer solutions and the moldings formed from melt polymers are indicated when using the same starting CPUI. It appears that films and moldings possess typical properties of elastomers. The reprocessing of studied copolymers by using the injection molding method allows to assign CPUI to the thermoplastic elastomers or so-called thermoelastoplasts.

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Gupta, Rakesh K., and Kim F. Auyeung. "Crystallization in polymer melt spinning." Journal of Applied Polymer Science 34, no. 7 (November 20, 1987): 2469–84. http://dx.doi.org/10.1002/app.1987.070340711.

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Skoura, Eva, Peter Boháč, Martin Barlog, Helena Palková, Martin Danko, Juraj Šurka, Andreas Mautner, and Juraj Bujdák. "Modified Polymer Surfaces: Thin Films of Silicate Composites via Polycaprolactone Melt Fusion." International Journal of Molecular Sciences 23, no. 16 (August 15, 2022): 9166. http://dx.doi.org/10.3390/ijms23169166.

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Polymer/layered silicate composites have gained huge attention in terms of research and industrial applications. Traditional nanocomposites contain particles regularly dispersed in a polymer matrix. In this work, a strategy for the formation of a composite thin film on the surface of a polycaprolactone (PCL) matrix was developed. In addition to the polymer, the composite layer was composed of the particles of saponite (Sap) modified with alkylammonium cations and functionalized with methylene blue. The connection between the phases of modified Sap and polymer was achieved by fusing the chains of molten polymer into the Sap film. The thickness of the film of several μm was confirmed using electron microscopy and X-ray tomography. Surfaces of precursors and composite materials were analyzed in terms of structure, composition, and surface properties. The penetration of polymer chains into the silicate, thus joining the phases, was confirmed by chemometric analysis of spectral data and changes in some properties upon PCL melting. Ultimately, this study was devoted to the spectral properties and photoactivity of methylene blue present in the ternary composite films. The results provide directions for future research aimed at the development of composite materials with photosensitizing, photodisinfection, and antimicrobial surfaces.

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Shmakova, N. S., I. A. Kirsh, and V. A. Romanova. "Influence of cationic surfactants on physical and mechanical properties of polymer compositions." Proceedings of the Voronezh State University of Engineering Technologies 82, no. 1 (May 15, 2020): 225–29. http://dx.doi.org/10.20914/2310-1202-2020-1-225-229.

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When creating filled polymer composite materials, difficulties often arise due to poor compatibility of polymers with modifying additives. To solve such problems, surface-active substances (SAS) are successfully used in many industries, but they are practically not used in polymer processing. This is largely due to the insufficient assortment of surfactants produced that are suitable for introduction into polymers, especially film-forming ones. Anionic and nonionic surfactants are used in the synthesis and processing of elastomers, but they are not used in the production of film materials. As for the use of cationic surfactants, there are still no data at all. They differ from other types of surfactants in a variety of structures, in the number and relative positions of cationic centers and hydrophobic radicals, and also in antimicrobial properties. The prospects of using quaternary ammonium salts for the modification of packaging materials are shown. The expediency of using cationic surfactants for the modification of polymeric materials is proved. It is shown that the use of quaternary ammonium salts improves the physical and mechanical properties of films based on polyethylene and polypropylene. It is proved that cationic surfactants are technologically compatible with polyolefins, which allows the processing of polymer compositions by extrusion. Today, the most common polymers for food packaging are polyethylene and polypropylene. This is due to their low cost, safety in contact with food products, and suitability for processing into films of different thicknesses. More and more attention is being paid to the creation of packaging materials with antimicrobial properties. The imparting of such properties is achieved by introducing an antimicrobial additive into the polymer melt. It is most expedient to introduce additives directly into the melt of the polymer composition during processing, since, for example, during the extrusion process, polymer homogenization with the additive.

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Zhou, Yang, Qiming He, Fan Zhang, Feipeng Yang, Suresh Narayanan, Guangcui Yuan, Ali Dhinojwala, and Mark D. Foster. "Modifying Surface Fluctuations of Polymer Melt Films with Substrate Modification." ACS Macro Letters 6, no. 9 (August 14, 2017): 915–19. http://dx.doi.org/10.1021/acsmacrolett.7b00459.

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Zhang, Fan, Qiming He, Yang Zhou, Suresh Narayanan, Chao Wang, Bryan D. Vogt, and Mark D. Foster. "Anomalous Confinement Slows Surface Fluctuations of Star Polymer Melt Films." ACS Macro Letters 7, no. 7 (June 25, 2018): 834–39. http://dx.doi.org/10.1021/acsmacrolett.8b00278.

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11

Li, Chunhua, Jun Jiang, Miriam H. Rafailovich, and Jonathan C. Sokolov. "Melt fracture in polymer thin films at strongly attractive surfaces." Europhysics Letters (EPL) 76, no. 5 (December 2006): 870–76. http://dx.doi.org/10.1209/epl/i2006-10353-8.

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12

Glasser, Wolfgang, Robert Loos, Blair Cox, and Nhiem Cao. "Melt-blown compostable polyester films with lignin." March 2017 16, no. 03 (2017): 111–21. http://dx.doi.org/10.32964/tj16.3.111.

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Compostable films for such uses as packaging and agricultural soil covering materials were first produced on commercial scale from blends of biodegradable polyesters and a modified kraft lignin. The lignin consisted of an industrial product isolated according to the LignoBoost process. The lignin modification involved homogeneous phase reaction with propylene oxide, and the films were melt-blown from a pelletized compound consisting of up to a 30% blend of lignin derivative with commercial biodegradable polyester. The 12–93 μm thick films combined the characteristics of lignin as modulus-building and environmentally degradable polymer with those of the strength-building thermoplastic polyester. Although the modified lignin paralleled the behavior of native lignin in wood by resisting rapid and full conversion to carbon dioxide in a simulated composting environment, two thirds of the film mass biodegraded within 12 weeks of composting, with the remainder turning into (humus-like) water-soluble solids and particles <2 mm in size. The lignin derivatives suffered from the release of trace amounts of malodorous volatiles containing reduced sulfur when subjected to melt-blowing. The objectionable odor was virtually unnoticeable in injection-molded solid parts.

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Brown, G. M., D. F. Brown, and J. H. Butler. "The analysis of “Gels” in polymer films." Proceedings, annual meeting, Electron Microscopy Society of America 47 (August 6, 1989): 362–63. http://dx.doi.org/10.1017/s0424820100153786.

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The term “gel”, in the jargon of the plastics film industry, may refer to any inclusion that produces a visible artifact in a polymeric film. Although they can occur in any plastic product, gels are a principle concern in films where they detract from the cosmetic appearance of the product and may compromise its mechanical strength by acting as local stress concentrators. Many film gels are small spheres or ellipsoids less than one millimeter in diameter whereas other gels are fusiform-shaped and may reach several centimeters in length. The actual composition of gel inclusions may vary from miscellaneous inorganics (i.e. glass and mineral particles) and processing additives to heavily oxidized, charred or crosslinked polymer. The most commonly observed gels contain polymer differing from the bulk of the sample in its melt viscosity, density or molecular weight.Polymeric gels are a special concern in polyethylene films. Over the years and with the examination of a variety of these samples three predominant polymeric species have been observed: density gels which have different crystallinity than the film; melt-index gels in which the molecular weight is different than the film and crosslinked gels which are comprised of crosslinked polyethylene.

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Swain, Aparna, Nafisa Begam, Sivasurender Chandran, M. S. Bobji, and J. K. Basu. "Engineering interfacial entropic effects to generate giant viscosity changes in nanoparticle embedded polymer thin films." Soft Matter 16, no. 16 (2020): 4065–73. http://dx.doi.org/10.1039/d0sm00019a.

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We demonstrate a new method to study the viscosity of PNC thin films, consisting of polymer grafted nanoparticles (PGNPs) embedded in un-entangled homopolymer melt films, using atomic force microscopy based force–distance spectroscopy.

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15

Zhao, Junnan, Aaron C. Tan, and Peter F. Green. "Thermally induced chain orientation for improved thermal conductivity of P(VDF-TrFE) thin films." J. Mater. Chem. C 5, no. 41 (2017): 10834–38. http://dx.doi.org/10.1039/c7tc03240d.

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A large increase in thermal conductivity κ was observed in a P(VDF-TrFE) thin film annealed above melting temperature due to extensive ordering of polymer backbone chains perpendicular to the substrate after recrystallization from the melt. This finding may lay out a straightforward method to improve the thin film κ of semicrystalline polymers whose chain orientation is sensitive to thermal annealing.

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Didenko, A. L., A. G. Ivanov, V. E. Smirnova, G. V. Vaganov, E. N. Popova, D. A. Kuznetsov, L. A. Myagkova, V. M. Svetlichniy, V. E. Yudin, and V. V. Kudryavtsev. "Comparative characteristics of products of processing of fusible copoly (urethane-imides) from the solutions and melts formed by them." Plasticheskie massy, no. 9-10 (November 29, 2022): 20–24. http://dx.doi.org/10.35164/0554-2901-2022-9-10-20-24.

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Self-supporting films and thick-walled moldings (blades) were obtained from solutions and melts of multiblock (segmental) copoly(urethane-imides). The initial copoly(urethane-imides) were obtained on the basis of aliphatic polyesters: poly(propyleneglycol), poly(diethyleneglycoladipinate) and polycaprolactone, dianhydride of 1,3-bis(3’,4-dicarboxyphenoxy) benzene and aromatic diamines: 4,4’-bis-(4”-aminophenoxy)biphenyl and 1,4-bis(4’-aminophenoxy)diphenylsulfone. Samples of films and moldings were studied by IR spectroscopy, TGA, DSC and mechanical analysis under static and dynamic (DMA) experimental conditions. It is assumed that the diff erences in the properties of films and moldings are due to an increase in the proportion of aromatic blocks due to microdestruction of polymer chains and increased interfacial interactions of polyester and urethanimide microphases (blocks) in polymer systems during the processing of polymers from the melt by injection molding.

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Xie, Sijia, Jerome Werder, and Helmut Schift. "Back Injection Molding of Sub-Micron Scale Structures on Roll-to-Roll Extrusion Coated Films." Polymers 13, no. 9 (April 27, 2021): 1410. http://dx.doi.org/10.3390/polym13091410.

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Roll-to-roll extrusion coated films were bonded onto polymer parts by back injection molding (BIM). The polypropylene (PP) coated polyethylene terephthalate (PET) films were pre-patterned with microstructured V-shaped grooves with 3.2 µm and 53 µm width, and other geometries. Bonding on PET and poly(methyl methacrylate) (PMMA) parts was facilitated by either higher tool or melt temperatures but was particularly enhanced by applying a mild oxygen plasma to the backside of the PET film prior to injection of the polymer melt. Silver wires from conductive nanoparticle ink were embedded into the PP coating during the BIM process by controlled collapse of the V-grooves. Thus, the feasibility of combining standard carrier film materials for printed flexible electronics and packaging into a non-flat polymer part was demonstrated, which could be a helpful step towards the fabrication of polymer parts with surface functionality.

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Chakraborty, Ayan, Mohini Sain, Mark Kortschot, and Sean Cutler. "Dispersion of Wood Microfibers in a Matrix of Thermoplastic Starch and Starch–Polylactic Acid Blend." Journal of Biobased Materials and Bioenergy 1, no. 1 (April 1, 2007): 71–77. http://dx.doi.org/10.1166/jbmb.2007.1980.

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The successful dispersion of cellulose fibers of submicrometer diameter in polymers has been restricted to solution-cast films so far. In this work, the dispersion of microfibers in biopolymers was investigated by melt-mixing using conventional processing equipment. Thermoplastic starch and a blend of starch and polylactic acid (PLA) were used as matrix materials. A suspension of cellulose microfibers less than 1 μm in diameter was prepared in water. This microfiber suspension was poured into molten thermoplastic starch to obtain fiber loadings up to 2%. The composites were compression molded into thin films roughly 0.25 mm thick. there was a 10% increase in tensile strength and a 50% increase in stiffness with each percentage increase in microfiber loading in the starch polymer. Similar improvement in tensile properties was also noted for a polymer system prepared by blending starch and PLA. Laser confocal microscopy images were analyzed to quantify microfiber dispersion at different composite processing parameters. This was the first work where successful dispersion of cellulose fibers of submicrometer was achieved in a composite prepared solely by the melt-mixing process.

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Tatke, Akshaya, Narendar Dudhipala, Karthik Janga, Bhavik Soneta, Bharathi Avula, and Soumyajit Majumdar. "Melt-Cast Films Significantly Enhance Triamcinolone Acetonide Delivery to the Deeper Ocular Tissues." Pharmaceutics 11, no. 4 (April 2, 2019): 158. http://dx.doi.org/10.3390/pharmaceutics11040158.

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Delivering an effective drug load to the posterior section of the ocular tissues, while using a non-invasive technique, has always been a challenge. In this regard, the goal of the present study was to develop sustained release triamcinolone acetonide (TA) loaded polymeric matrix films for ocular delivery. The TA-films were prepared in two different polymer matrices, with drug loadings of 10% and 20% w/w, and they were evaluated for ocular distribution in vivo in a conscious rabbit model. A 4% w/v TA suspension (TA-C) was used as a control for in vitro and in vivo studies. The TA-films, prepared with melt-cast technology, used polyethylene oxide (PEO) and Soluplus® as the polymer matrix. The films were evaluated with respect to assay, content uniformity, excipient interaction, and permeability across isolated rabbit sclera. The distribution of TA in the ocular tissues, post topical administration, was determined in New Zealand male albino rabbits as a function of dose, and was compared against TA-C. The assay of the 10% and 20% w/w film was in the range from 70–79% and 92–94% for the Soluplus® and PEO films, respectively, and content uniformity was in the range of 95–103% for both the films. The assay of the TA from Soluplus® films was less compared with the PEO films and showed an interaction with TA, as revealed by Differential Scanning Calorimetry (DSC). Hence, Soluplus® films were not selected for further studies. No interaction was observed between the drug and PEO polymer matrix. The enhancement of trans-scleral flux and permeability of TA was about 1.16 and 1.33-folds, respectively, from the 10% w/w PEO and 3.5 and 2.12-folds, respectively, from the 20% w/w PEO films, as compared with TA-C formulations. The in vivo studies demonstrate that significantly higher TA levels were observed in the anterior and posterior segments of the eye at the end of 6h with the PEO films. Therefore, the PEO based polymeric films were able to deliver TA into the back of the eye efficiently and for prolonged periods.

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Jang, Hyunho, Sangwoo Kwon, Sun Jong Kim, and Su-il Park. "Maleic Anhydride-Grafted PLA Preparation and Characteristics of Compatibilized PLA/PBSeT Blend Films." International Journal of Molecular Sciences 23, no. 13 (June 28, 2022): 7166. http://dx.doi.org/10.3390/ijms23137166.

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Poly(butylene sebacate-co-terephthalate) (PBSeT) is a biodegradable flexible polymer suitable for melt blending with other biodegradable polymers. Melt blending with a compatibilizer is a common strategy for increasing miscibility between polymers. In this study, PBSeT polyester was synthesized, and poly(lactic acid) (PLA) was blended with 25 wt% PBSeT by melt processing with 3–6 phr PLA-grafted maleic anhydride (PLA-g-MAH) compatibilizers. PLA-g-MAH enhanced the interfacial adhesion of the PLA/PBSeT blend, and their mechanical and morphological properties confirmed that the miscibility also increased. Adding more than 6 phr of PLA-g-MAH significantly improved the mechanical properties and accelerated the cold crystallization of the PLA/PBSeT blends. Furthermore, the thermal stabilities of the blends with PLA-g-MAH were slightly enhanced. PLA/PBSeT blends with and without PLA-g-MAH were not significantly different after 120 h, whereas all blends showed a more facilitated hydrolytic degradation rate than neat PLA. These findings indicate that PLA-g-MAH effectively improves PLA/PBSeT compatibility and can be applied in the packaging industry.

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Chen, R. T., M. G. Jamieson, and R. Callahan. "SEM/FESEM imaging of lamellar structures in melt extruded polyethylene films." Proceedings, annual meeting, Electron Microscopy Society of America 50, no. 2 (August 1992): 1142–43. http://dx.doi.org/10.1017/s0424820100130341.

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“Row lamellar” structures have previously been observed when highly crystalline polymers are melt-extruded and recrystallized under high stress. With annealing to perfect the stacked lamellar superstructure and subsequent stretching in the machine (extrusion) direction, slit-like micropores form between the stacked lamellae. This process has been adopted to produce polymeric membranes on a commercial scale with controlled microporous structures. In order to produce the desired pore morphology, row lamellar structures must be established in the membrane precursors, i.e., as-extruded and annealed polymer films or hollow fibers. Due to the lack of pronounced surface topography, the lamellar structures have typically been investigated by replica-TEM, an indirect and time consuming procedure. Recently, with the availability of high resolution imaging techniques such as scanning tunneling microscopy (STM) and field emission scanning electron microscopy (FESEM), the microporous structures on the membrane surface as well as lamellar structures in the precursors can be directly examined.The materials investigated are Celgard® polyethylene (PE) flat sheet membranes and their film precursors, both as-extruded and annealed, made at different extrusion rates (E.R.).

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Tarasova E. Yu., Zhuravleva I. I., Bakulin I. A., Kuznetsov S. I., and Panin A. S. "Structure and phase composition of films synthesized by laser sintering from polyvinylidene fluoride of various grades." Technical Physics Letters 48, no. 15 (2022): 14. http://dx.doi.org/10.21883/tpl.2022.15.53811.18913.

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The processes of laser synthesis of films with a thickness of 80-230 μm from polyvinylidene fluoride of various grades are studied. It is established that the range of synthesis modes does not depend on the grades of PVDF. The content of the piezo active β-phase decreases after laser treatment, but the complete transformation of β-> α does not occur. The process of thermos-oxidative degradation after laser treatment is not observed. Under the same treatment conditions, the higher the open porosity coefficient, the lower the polymer melt flow index (MFI). Depending on the MFI of the initial polymer, the selection of laser exposure modes can control the porosity of the films in the range of 26-68%. Keywords: laser treatment, polyvinylidene fluoride (PVDF), porous films, melt flow index.

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Sonnenberg, Maria, René Gustus, Sascha Sedelmeier, Lienhard Wegewitz, Oliver Höfft, Jürgen Wieser, and Wolfgang Maus-Friedrichs. "Polymer-induced metal diffusion during plastic processing: a reason for deposit formation." Journal of Polymer Engineering 39, no. 5 (May 1, 2019): 472–80. http://dx.doi.org/10.1515/polyeng-2018-0324.

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Abstract In the plastic-processing industry, the formation of unknown deposits at the interface between polymer melt and steel surfaces can pose major challenges, which occurs especially on screws, barrels, and tools. These deposits will detach during production and lead to quality restrictions mostly as spots in the products. We investigated the interactions between tool steel and polymer melt, especially polycarbonate, in the early stages of deposit formation. Steel-polymer-composite samples are prepared close to the realistic conditions in the plastic-processing industry. To get further insight, thin polymer films on tool steel specimens and its alloy elements, representing model systems, are prepared. X-ray-photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES) are used to characterize the interfaces chemically. Additionally, atomic force microscopy (AFM) and scanning electron microscopy (SEM) were used. We found iron and chromium diffusion into the polycarbonate melt induced by polymer metal interaction. Iron and polymer chains are immobilized at the interface by a chemical interaction, while chromium does not chemically interact with the polymer melt. Basing on these results, we propose a mechanism for deposit formation in plastic-processing machines and tools.

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Emamifar, Aryou, Mahdi Kadivar, Mohammad Shahedi, and Sabihe Soleimanian-Zad. "Preparation and Evaluation of Nanocomposite LDPE Films Containing Ag and ZnO for Food-Packaging Applications." Advanced Materials Research 129-131 (August 2010): 1228–32. http://dx.doi.org/10.4028/www.scientific.net/amr.129-131.1228.

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Nanocomposite polymer films were produced from composites comprising LDPE /nanosilver and LDPE/nano-ZnO by melt compounding. The mechanical properties of the films prepared were characterized by using stress-strain analysis. Dispersion quality of nanomaterials into the polymer matrix film was monitored using the Transmission Electron Microscopy. The results showed the nanocomposites as possessing lower elongation at break and more antimicrobial activity with the increase of each of nanofillers content.

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Li, Youbing, Kaizhi Shen, and Jie Zhan. "Improving rheological property of polymer melt via low frequency melt vibration." Journal of Applied Polymer Science 102, no. 6 (2006): 5292–96. http://dx.doi.org/10.1002/app.24791.

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Verney, Vincent, Audrey Ramoné, Florence Delor-Jestin, Sophie Commereuc, Marek Koutny, Geoffrey Perchet, and Julien Troquet. "Melt Viscoelastic Assessment of Poly(Lactic Acid) Composting: Influence of UV Ageing." Molecules 23, no. 10 (October 18, 2018): 2682. http://dx.doi.org/10.3390/molecules23102682.

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This study is devoted to the degradation pathway (bio, photo degradation and photo/bio) of Poly(Lactic acid) PLA polymers by means of melt viscoelasticity. A comparison was made between three PLA polymers with different microstructures (L, D stereoisomers). Biodegradability was determined during composting by burying the polymer films in compost at 58 °C. Melt viscoelasticity was used to assess the molecular evolution of the materials during the composting process. Viscoelastic data were plotted in the complex plane. We used this methodology to check the kinetics of the molecular weight decrease during the initial stages of the degradation, through the evolution of Newtonian viscosity. After a few days in compost, the Newtonian viscosity decreased sharply, meaning that macromolecular chain scissions began at the beginning of the experiments. However, a double molar mass distribution was also observed on Cole–Cole plots, indicating that there is also a chain recombination mechanism competing with the chain scission mechanism. PLA hydrolysis was observed by infra-red spectroscopy, where acid characteristic peaks appeared and became more intense during experiments, confirming hydrolytic activity during the first step of biodegradation. During UV ageing, polymer materials undergo a deep molecular evolution. After photo-degradation, lower viscosities were measured during biodegradation, but no significant differences in composting were found.

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Redondo, Alexandre, Sourav Chatterjee, Pierre Brodard, LaShanda T. J. Korley, Christoph Weder, Ilja Gunkel, and Ullrich Steiner. "Melt-Spun Nanocomposite Fibers Reinforced with Aligned Tunicate Nanocrystals." Polymers 11, no. 12 (November 20, 2019): 1912. http://dx.doi.org/10.3390/polym11121912.

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The fabrication of nanocomposite films and fibers based on cellulose nanocrystals (P-tCNCs) and a thermoplastic polyurethane (PU) elastomer is reported. High-aspect-ratio P-tCNCs were isolated from tunicates using phosphoric acid hydrolysis, which is a process that affords nanocrystals displaying high thermal stability. Nanocomposites were produced by solvent casting (films) or melt-mixing in a twin-screw extruder and subsequent melt-spinning (fibers). The processing protocols were found to affect the orientation of both PU hard segments and the P-tCNCs within the PU matrix and therefore the mechanical properties. While the films were isotropic, both the polymer matrix and the P-tCNCs proved to be aligned along the fiber direction in the fibers, as shown using SAXS/WAXS, angle-dependent Raman spectroscopy, and birefringence analysis. Tensile tests reveal that fibers and films, at similar P-tCNC contents, display Young’s moduli and strain-at-break that are within the same order of magnitude, but the stress-at-break was found to be ten-times higher for fibers, conferring them a superior toughness over films.

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Cabello-Alvarado, Christian J., Zoe V. Quiñones-Jurado, Víctor J. Cruz-Delgado, and Carlos A. Avila-Orta. "Pigmentation and Degradative Activity of TiO2 on Polyethylene Films Using Masterbatches Fabricated Using Variable-Frequency Ultrasound-Assisted Melt-Extrusion." Materials 13, no. 17 (September 1, 2020): 3855. http://dx.doi.org/10.3390/ma13173855.

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Ultrasound-assisted melt-extrusion method (USME) is a high-quality process used to produce polymeric compounds with an adequate homogeneous dispersion. This study evaluates white-color films of linear low-density polyethylene (LLDPE) prepared using TiO2 masterbatch obtained by ultrasound-assisted melt-extrusion at variable frequencies (USME-VF). LLDPE with three different melt-flow indices (2, 20 and 50 g/10 min) were used as the polymer matrix. The films were obtained from the dilution of masterbatches of LLDPE (melt-flow index = 2) at a concentration of 7 wt% TiO2. The morphology, pigmentation, TiO2 reactivity, and the mechanical stability of the films were assessed. The masterbatch compounds were evaluated by melt-flow index (MFI) and scanning electron microscopy (SEM). The contrast ratio, yellowness index and mechanical properties of films were also measured. The properties of whiteness and elongation at break improved in the films prepared using masterbatches with higher dispersion. Though the reactivity of the TiO2 particles increased during accelerated aging, it did not affect the elongation to rupture. The yellowness index was moderately affected in films that included TiO2 particles processed using USME-VF.

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Miles, M. J., K. D. Jandt, T. J. McMaster, and R. L. Williamson. "Atomic force microscopy of polymer single crystals and melt-drawn films." Colloids and Surfaces A: Physicochemical and Engineering Aspects 87, no. 3 (August 1994): 235–43. http://dx.doi.org/10.1016/0927-7757(94)80071-5.

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Venkatesh, R. Bharath, Neha Manohar, Yiwei Qiang, Haonan Wang, Hong Huy Tran, Baekmin Q. Kim, Anastasia Neuman, et al. "Polymer-Infiltrated Nanoparticle Films Using Capillarity-Based Techniques: Toward Multifunctional Coatings and Membranes." Annual Review of Chemical and Biomolecular Engineering 12, no. 1 (June 7, 2021): 411–37. http://dx.doi.org/10.1146/annurev-chembioeng-101220-093836.

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Polymer-infiltrated nanoparticle films (PINFs) are a new class of nanocomposites that offer synergistic properties and functionality derived from unusually high fractions of nanomaterials. Recently, two versatile techniques,capillary rise infiltration (CaRI) and solvent-driven infiltration of polymer (SIP), have been introduced that exploit capillary forces in films of densely packed nanoparticles. In CaRI, a highly loaded PINF is produced by thermally induced wicking of polymer melt into the nanoparticle packing pores. In SIP, exposure of a polymer–nanoparticle bilayer to solvent vapor atmosphere induces capillary condensation of solvent in the pores of nanoparticle packing, leading to infiltration of polymer into the solvent-filled pores. CaRI/SIP PINFs show superior properties compared with polymer nanocomposite films made using traditional methods, including superb mechanical properties, thermal stability, heat transfer, and optical properties. This review discusses fundamental aspects of the infiltration process and highlights potential applications in separations, structural coatings, and polymer upcycling—a process to convert polymer wastes into useful chemicals.

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JOTANIA, RAJSHREE, CHETAN CHANMAL, and JYOTI JOG. "MAGNETIC AND DIELECTRIC PROPERTIES OF POLYMER-CERAMIC COMPOSITES SYNTHESIZED USING A MELT COMPOUND TECHNIQUE." International Journal of Modern Physics: Conference Series 22 (January 2013): 552–57. http://dx.doi.org/10.1142/s2010194513010659.

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Polymer composites have emerged as a new class of materials, which have attracted technologist as they display novel properties compared to traditional materials and dramatically improves the performance properties of polymer system. We have synthesized hexaferrite-polymer composites of Polyvinylidene Fluride (PVDF) with BaCa2Fe16O27 (2.0, 5.0 % wt/vol.) using a melt compounding technique. BaCa2Fe16O27 hexaferrite powder was prepared using a microemulsion technique and directly mixed in melted PVDF, following by a low temperature hot pressing. The composites of PVDF with various weight percent of BaCa2Fe16O27 (2.0 & 5.0% wt/vol.) were processed via melt mixing at 200°C, with 60 rpm for 5 minutes. The films of uniform thickness are about 0.5 mm is obtained by a compression molded instrument at 200°C under 5-ton pressure. The influence of BaCa2Fe16O27 hexaferrite contents on magnetic and dielectric properties of composite was investigated. The prepared PVDF- BaCa2Fe16O27 composite thick films were characterized for their magnetic; dielectric and thermal behavior employing magnetic, dielectric and thermal analysis (TGA/DTA). Maximum saturation magnetization was obtained for 5 % wt/vol. of barium calcium hexaferrite composite.

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Hristov, Velichko. "Melt Flow Instabilities of Wood Polymer Composites." Composite Interfaces 16, no. 7-9 (January 2009): 731–50. http://dx.doi.org/10.1163/092764409x12477434799525.

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Li, Huayi, Yucai Ke, and Youliang Hu. "Polymer nanofibers prepared by template melt extrusion." Journal of Applied Polymer Science 99, no. 3 (2005): 1018–23. http://dx.doi.org/10.1002/app.22597.

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Revelas, Constantinos J., Aristotelis P. Sgouros, Apostolos T. Lakkas, and Doros N. Theodorou. "RuSseL: A Self-Consistent Field Theory Code for Inhomogeneous Polymer Interphases." Computation 9, no. 5 (May 10, 2021): 57. http://dx.doi.org/10.3390/computation9050057.

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In this article, we publish the one-dimensional version of our in-house code, RuSseL, which has been developed to address polymeric interfaces through Self-Consistent Field calculations. RuSseL can be used for a wide variety of systems in planar and spherical geometries, such as free films, cavities, adsorbed polymer films, polymer-grafted surfaces, and nanoparticles in melt and vacuum phases. The code includes a wide variety of functional potentials for the description of solid–polymer interactions, allowing the user to tune the density profiles and the degree of wetting by the polymer melt. Based on the solution of the Edwards diffusion equation, the equilibrium structural properties and thermodynamics of polymer melts in contact with solid or gas surfaces can be described. We have extended the formulation of Schmid to investigate systems comprising polymer chains, which are chemically grafted on the solid surfaces. We present important details concerning the iterative scheme required to equilibrate the self-consistent field and provide a thorough description of the code. This article will serve as a technical reference for our works addressing one-dimensional polymer interphases with Self-Consistent Field theory. It has been prepared as a guide to anyone who wishes to reproduce our calculations. To this end, we discuss the current possibilities of the code, its performance, and some thoughts for future extensions.

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Yamada, Shinji. "Aging and stiction dynamics in confined films of a star polymer melt." Journal of Chemical Physics 137, no. 19 (November 21, 2012): 194702. http://dx.doi.org/10.1063/1.4766468.

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Sahoo, Rajesh Kumar. "Preparation of PP/PP-g-MAH/C15A Nanocomposite by Melt Extrusion Process and Comparative Study of its Mechanical and Non-Isothermal Crystallization Behaviour." International Journal for Research in Applied Science and Engineering Technology 9, no. VII (July 31, 2021): 3744–57. http://dx.doi.org/10.22214/ijraset.2021.37167.

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Nanocomposite films have been prepared by melt blending method with the help of twin screw extruder using polymer polypropylene(PP)nucleating agent like organically modified nanoclay at optimum loading condition. Compatibilizers such as polypropylene grafted maleic anhydride (PP-g-MAH) were used for better compatibility between polymer matrix and filler. The effect of organoclay on nucleation effect and subsequent incremental values in mechanical and thermal behavior of different nanocomposite films has been investigated and explained with justifications. The tensile properties have shown to be improved in presence of clay nanoparticles due to resistance exerted by clay layers against plastic deformation of the polymer. Thermal properties measured by differential scanning calorimeter shows increased crystallization temperature of the nanocomposites in presence of clay particles and compatibilizer of optimum concentration.

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Boehm, Anna K., Emanuel Ionescu, Marcus Koch, and Markus Gallei. "Combining Soft Polysilazanes with Melt-Shear Organization of Core–Shell Particles: On the Road to Polymer-Templated Porous Ceramics." Molecules 24, no. 19 (September 30, 2019): 3553. http://dx.doi.org/10.3390/molecules24193553.

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The preparation of ordered macroporous SiCN ceramics has attracted significant interest and is an attractive area for various applications, e.g., in the fields of catalysis, gas adsorption, or membranes. Non-oxidic ceramics, such as SiCN, own a great stability based on the covalent bonds between the containing elements, which leads to interesting properties concerning resistance and stability at high temperature. Their peculiar properties have become more and more important for a manifold of applications, like catalysis or separation processes, at high temperatures. Within this work, a feasible approach for the preparation of ordered porous materials by taking advantage of polymer-derived ceramics is presented. To gain access to free-standing films consisting of porous ceramic materials, the combination of monodisperse organic polymer-based colloids with diameters of 130 nm and 180 nm featuring a processable preceramic polymer is essential. For this purpose, the tailored design of hybrid organic/inorganic particles featuring anchoring sites for a preceramic polymer in the soft shell material is developed. Moreover, polymer-based core particles are used as sacrificial template for the generation of pores, while the preceramic shell polymer can be converted to the ceramic matrix after thermal treatment. Two different routes for the polymer particles, which can be obtained by emulsion polymerization, are followed for covalently linking the preceramic polysilazane Durazane1800 (Merck, Germany): (i) Free radical polymerization and (ii) atom transfer radical polymerization (ATRP) conditions. These hybrid hard core/soft shell particles can be processed via the so-called melt-shear organization for the one-step preparation of free-standing particle films. A major advantage of this technique is the absence of any solvent or dispersion medium, enabling the core particles to merge into ordered particle stacks based on the soft preceramic shell. Subsequent ceramization of the colloidal crystal films leads to core particle degradation and transformation into porous ceramics with ceramic yields of 18–54%.

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Semeniuk, I. V., V. V. Kochubei, V. Y. Skorokhoda, Y. Y. Melnyk, N. B. Semenyuk, N. I. Koretska, and T. Y. Pokynbroda. "Temperature and physical-mechanical properties of thermoplastic materials based on polyhydroxybutyrate." Voprosy Khimii i Khimicheskoi Tekhnologii, no. 6 (December 2022): 80–87. http://dx.doi.org/10.32434/0321-4095-2022-145-6-80-87.

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The temperature and physical-mechanical properties of polyhydroxybutyrate obtained during the cultivation of Azotobacter vinelandii N-14 bacteria strain, polylactic acid, poly(-caprolactone) and their blends were studied. Polymer samples in the form of films with a thickness of 50 m were cast on silicate glass plates applying 3% solutions of biopolymers in chloroform and subjected to heat treatment in an air thermostat at the temperature of 1100C for 20 minutes. It was found that the previous heat treatment of the studied biodegradable polymers increases their heat resistance which is evidenced by the shift of their thermal effects of melting to higher temperature area. It was determined that films based on polyhydroxybutyrate/polylactic acid/poly(-caprolactone) (20:55:25 wt.%) blend possesses improved mechanical properties. The film relative elongation at break increases from 3% to 46% for polyhydroxybutyrate and for the mixture, respectively. This is explained by the presence of poly(-caprolactone) polymers in above mixture. At the same time, despite the lower tensile strength characteristic which are typical of poly(-caprolactone), this value is higher for the polymer blends than for polyhydroxybutyrate (38.3 and 33.0 MPa, respectively). This is due to the high polylactic acid content (55%) in the polymer composition. The presence of poly(-caprolactone) (25%) in the blend improves the fluidity of its melt which will enable to reduce the temperature of product formation. The derived polymer mixture is recommended for the manufacturing of various packaging materials for food, agricultural and pharmaceutical products.

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Wang, Xiaohui, Feifei Yan, Xue Bai, Hanchuan Li, Ming Yuan, Yanping Liu, Benjamin S. Hsiao, Chuntai Liu, and Zhen Wang. "Lamellar crystal-dominated surfaces of polymer films achieved via melt stretching-induced free surface crystallization." Soft Matter 17, no. 48 (2021): 10829–38. http://dx.doi.org/10.1039/d1sm01492g.

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Yan, Zheng, Kai Zhi Shen, Jie Zhang, Li Min Chen, and Chixing Zhou. "Effect of vibration on rheology of polymer melt." Journal of Applied Polymer Science 85, no. 8 (June 11, 2002): 1587–92. http://dx.doi.org/10.1002/app.10649.

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Nagel, Jürgen, Philipp Zimmermann, Simona Schwarz, and Kornelia Schlenstedt. "Selective Grafting of Polyamines to Polyether Ether Ketone Surface during Molding and Its Use for Chemical Plating." Coatings 8, no. 10 (September 22, 2018): 333. http://dx.doi.org/10.3390/coatings8100333.

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We present a new approach of surface functionalization of polyether ether ketone (PEEK) that is carried out during the molding step. Thin films of polymers with different functional groups were applied to the surface of a mold and brought in close contact with a PEEK melt during injection molding. The surfaces of the produced parts were characterized after solidification. Only those PEEK surfaces that were in contact with polymers bearing primary amino groups exhibited a wettability for water. Obviously, the thin polymer film was grafted to the surface by a chemical reaction initiated by the high melt temperature. The formation of azomethine bonds between PEEK and the polyamine by coupling to the ketone groups was proposed. The other amino groups in the molecule were still in function after the molding process. They adsorbed different anionic molecules and anionic charged nanoparticles from aqueous solutions. The surfaces could be chemically plated by copper and nickel with high adhesion.

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Sareeladdanon, Supavinee, and Pranut Potiyaraj. "Mechanical Properties of PLA/LLDPE Films Reinforced with Silica from Rice Husk." Advanced Materials Research 1025-1026 (September 2014): 221–26. http://dx.doi.org/10.4028/www.scientific.net/amr.1025-1026.221.

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Nanocomposite is one of the most favorable approaches to improve mechanical properties of polymers. This study prepared polymer composite of PLA and LLDPE with different amount of rice husk silica (0.5 and 1 wt%). The composites were prepared by melt-mixing in a twin-screw extruder and processed into film by a chill roll cast extruder. The mechanical properties were investigated through tensile testing and tear testing. The result show that the tensile modulus of PLA decreased with 1wt% rice husk silica. Similarly, tensile modulus of LLDPE dropped with the addition of silica. However, with the addition 0.5 and 1 wt% rice husk silica, the elongation at break of PLA and LLDPE composites increases significantly.

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Czech, Zbigniew, and Agnieszka Butwin. "UV-crosslinkable warm-melt pressure-sensitive adhesives based on acrylics." Polish Journal of Chemical Technology 12, no. 4 (January 1, 2010): 58–61. http://dx.doi.org/10.2478/v10026-010-0051-9.

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UV-crosslinkable warm-melt pressure-sensitive adhesives based on acrylics The target of this article is to show the preparation of new generation of UV-crosslinkable warm-melt acrylic pressure-sensitive adhesives (PSAs) and the experimental test of their adhesive properties in comparison with typical conventional hot-melts adhesives. New generation of UV-crosslinkable acrylic warm-melts PSAs containing unsaturated photoinitiator, incorporated during polymerization process into polymer chain, and photoreactive diluents added to PSA systems after polymerization allows producing of wide range of self-adhesive materials, such as labels, mounting tapes, masking and splicing tapes, and sign and marking films.

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Galyon, Hailey, Samuel Vibostok, Jane Duncan, Gonzalo Ferreira, Abby Whittington, Kirk Havens, Jason McDevitt, and Rebecca Cockrum. "Clearance of Biodegradable Polymer and Polyethylene Films from the Rumens of Holstein Bull Calves." Animals 13, no. 5 (March 3, 2023): 928. http://dx.doi.org/10.3390/ani13050928.

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Due to the occurrence of plastic impaction in ruminants and its deleterious effects on health and production, it is necessary to determine the suitability of biodegradable polymers to replace polyethylene-based agricultural plastics, such as hay netting. The objectives of this study were to evaluate the clearance of a polyhydroxyalkanoate (PHA) and poly(butylene succinate-co-adipate) (PBSA) melt-blend polymer from the rumen when fed to cattle and subsequent animal health. Twelve Holstein bull calves were dosed with an encapsulated 13.6 g of PBSA:PHA (Blend), 13.6 g of low-density polyethylene (LDPE), or four empty gelatin capsules (Control) for 30 d. The feed intake, body weight, and body temperature were evaluated, and hemograms were run on d 0 and d 30. On d 31, calves were euthanized to evaluate gross rumen measurements and pathology, papillae length, and polymer residues in rumen contents. No calves presented any signs related to plastic impaction. The feed intake; body weight; rectal temperature; hematological parameters; gross rumen measurements and pathology; and rumen pH and temperature were not affected by treatments. Calves dosed with LDPE had 27 g of undegraded polymer retained in the rumen while Blend calves had only 2 g of fragmented polymers that were 10% of their original size. Agricultural plastics developed from PBSA:PHA may be a suitable alternative to LDPE-based products in the case of animal ingestion and may reduce the incidence of plastic impaction.

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Новак, Д. С., В. П. Плаван, Ю. В. Гуленок, and В. О. Стіхіляс. "РОЗРОБКА АНТИСТАТИЧНИХ І НАПІВПРОВІДНИКОВИХ КОМПОЗИЦІЙ ПОЛІЕТИЛЕН/ПОЛІАНІЛІН ТА ПОЛІВІНІЛХЛОРИД/ПОЛІАНІЛІН." Bulletin of the Kyiv National University of Technologies and Design. Technical Science Series 138, no. 5 (February 3, 2020): 71–78. http://dx.doi.org/10.30857/1813-6796.2019.5.8.

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The effect of the polyaniline content on the mechanical, rheological and electrical properties of polyethylene and polyvinylchloride compositions for the production of antistatic and semiconductive materials was established. Samples of polymer composites were obtained in two stages: 1) mixing of components in a mixer type "disk in disk"; 2) pressing into films by the method of "hot pressing." Tensile strength, relative elongation, melt flow index and specific volume electrical resistance of the compositions were investigated by standard methods. It was found that an increase in the volume content of polyaniline in the polyethylene and polyvinylchloride matrix leads to a monotonic decrease in the melt flow index, as well as tensile strength and relative elongation. At the same time, there is a significant decrease in the specific volume electrical resistance in polyethylene and polyvinylchloride composite films, which contain up to 30% vol. of polyaniline. The reduction of the tensile strength and the relative elongation of films from compositions containing up to 30% vol. of polyaniline. This is due to the decrease in the viscosity of the melt-filled compositions, as evidenced by the decrease in the flow index of the melt polyethylene compositions from 3 to 2 g / 10 min, and polyvinylchloride – from 13 to 3 g / 10 min. Specific volume electrical resistance naturally decreases with increasing volume concentration of the filler in ranges from 1014 to 102 Ohm ∙ m for polyethylene compositions and from 1010 to 101 Ohm ∙ m for polyvinylchloride compositions. The developed polyethylene and polyvinylchloride compositions filled with polyaniline can be used for the production of polymer products with antistatic and semiconductive properties.

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Jinescu, Valeriu V., Mihail Juganaru, Cosmin Jinescu, and Nicoleta Sporea. "Determination of an Extrusion Machine Performance Based on the Working Field of the Extruder Die." Materiale Plastice 58, no. 3 (October 5, 2021): 217–30. http://dx.doi.org/10.37358/mp.21.3.5519.

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Some inventions along with theoretical and experimental research made it possible to increase the output of a thermally homogeneous melt provided by the screw. However, the quality of the extruded product depends on some specific features of the extrusion die and to a large extent on the rheological behavior (viscous and elastic) of the polymer melt. The mismatch between the design of the screw-cylinder subassembly and the design of the extrusion die results in products with relatively short service life. The present paper has drawn up the working field of the extruder die and adjusted it based on the limitations imposed by the screw-cylinder subassembly, namely: - the maximum output rate that ensures the required thermal homogeneity of the melt; - the maximum output at which the heating system on the barrel (and possibly the screw) ensures the extrusion temperature; - the minimum economic output corresponding to the diameter of the screw. The working field of some extrusion dies for blown films of the following polymers have been plotted: polypropylene, low density polyethylene, high density polyethylene and ethylene vinyl acetate.

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Jinescu, Valeriu V., Mihail Juganaru, Cosmin Jinescu, and Nicoleta Sporea. "Determination of an Extrusion Machine Performance Based on the Working Field of the Extruder Die." Materiale Plastice 58, no. 3 (October 5, 2021): 217–30. http://dx.doi.org/10.37358/mp.21.3.5519.

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Some inventions along with theoretical and experimental research made it possible to increase the output of a thermally homogeneous melt provided by the screw. However, the quality of the extruded product depends on some specific features of the extrusion die and to a large extent on the rheological behavior (viscous and elastic) of the polymer melt. The mismatch between the design of the screw-cylinder subassembly and the design of the extrusion die results in products with relatively short service life. The present paper has drawn up the working field of the extruder die and adjusted it based on the limitations imposed by the screw-cylinder subassembly, namely: - the maximum output rate that ensures the required thermal homogeneity of the melt; - the maximum output at which the heating system on the barrel (and possibly the screw) ensures the extrusion temperature; - the minimum economic output corresponding to the diameter of the screw. The working field of some extrusion dies for blown films of the following polymers have been plotted: polypropylene, low density polyethylene, high density polyethylene and ethylene vinyl acetate.

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48

Bitsch, Martin, Anna Katharina Boehm, Alexander Grandjean, Gregor Jung, and Markus Gallei. "Embedding Photoacids into Polymer Opal Structures: Synergistic Effects on Optical and Stimuli-Responsive Features." Molecules 26, no. 23 (December 3, 2021): 7350. http://dx.doi.org/10.3390/molecules26237350.

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Opal films with their vivid structural colors represent a field of tremendous interest and obtained materials offer the possibility for many applications, such as optical sensors or anti-counterfeiting materials. A convenient method for the generation of opal structures relies on the tailored design of core-interlayer-shell (CIS) particles. Within the present study, elastomeric opal films were combined with stimuli-responsive photoacids to further influence the optical properties of structurally colored materials. Starting from cross-linked polystyrene (PS) core particles featuring a hydroxy-rich and polar soft shell, opal films were prepared by application of the melt-shear organization technique. The photoacid tris(2,2,2-trifluoroethyl) 8-hydroxypyrene-1,3,6-trisulfonate (TFEHTS) could be conveniently incorporated during freeze-drying the particle dispersion and prior to the melt-shear organization. Furthermore, the polar opal matrix featuring hydroxylic moieties enabled excited-state proton transfer (ESPT), which is proved by spectroscopic evaluation. Finally, the influence of the photoacid on the optical properties of the 3-dimensional colloidal crystals were investigated within different experimental conditions. The angle dependence of the emission spectra unambiguously shows the selective suppression of the photoacid’s fluorescence in its deprotonated state.

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Vowinkel, S., C. G. Schäfer, G. Cherkashinin, C. Fasel, F. Roth, N. Liu, C. Dietz, E. Ionescu, and M. Gallei. "3D-ordered carbon materials by melt-shear organization for tailor-made hybrid core–shell polymer particle architectures." Journal of Materials Chemistry C 4, no. 18 (2016): 3976–86. http://dx.doi.org/10.1039/c5tc03483c.

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The melt-shear organization technique for tailor-made polystyrene-co-polyacrylonitrile (PSAN) shell and silica core particles is investigated yielding easy-scalable carbonaceous porous films after etching and appropriate thermal treatment.

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Jiang, Youwei, Bingqing Luo, and Xing Cheng. "Enhanced Thermal Stability of Thermoplastic Polymer Nanostructures for Nanoimprint Lithography." Materials 12, no. 3 (February 12, 2019): 545. http://dx.doi.org/10.3390/ma12030545.

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Thermoplastic polymer micro- and nanostructures suffer pattern decay when heated to a temperature close to or above the polymer’s glass transition temperature. In this work, we report enhanced thermal stability of polycarbonate nanostructures at temperatures well above their glass transition temperatures. Based on this observation, we develop a unique technique for high-resolution polymer patterning by polymer reflows. This technique is characterized as the precise control of polymer reflows regardless of the annealing time, which avoids the time-domain nonlinear reflow of the polymer melt. We also implement thermal nanoimprinting in a step-and-repeat fashion, which dramatically increases the throughput of the thermal nanoimprint. The enhanced pattern stability against thermal reflow also allows for multiple imprinting at the same location to generate complex resist patterns from a simple mold structure. Since modern lithography often uses thin resist films (sub-100 nm) due to the restraint from the pattern aspect ratio, the unusual annealing behavior of thin polymer films is highly relevant in sub-100 nm lithographic processing.

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Journal articles on the topic 'Polymer Melt Films'

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