Journal articles: 'Thick polymers'

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Marenduzzo, Davide, Alessandro Flammini, Antonio Trovato, Jayanth R. Banavar, and Amos Maritan. "Physics of thick polymers." Journal of Polymer Science Part B: Polymer Physics 43, no. 6 (2005): 650–79. http://dx.doi.org/10.1002/polb.20363.

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Gong, Xue, Guangwu Li, Cuihong Li, Jicheng Zhang, and Zhishan Bo. "Benzothiadiazole based conjugated polymers for high performance polymer solar cells." Journal of Materials Chemistry A 3, no. 40 (2015): 20195–200. http://dx.doi.org/10.1039/c5ta06065f.

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Kaufmann, Thomas, Akhilesh Verma, Van-Tan Truong, Bo Weng, Roderick Shepherd, and Christophe Fumeaux. "Efficiency of a Compact Elliptical Planar Ultra-Wideband Antenna Based on Conductive Polymers." International Journal of Antennas and Propagation 2012 (2012): 1–11. http://dx.doi.org/10.1155/2012/972696.

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A planar antenna for ultra-wideband (UWB) applications covering the 3.1–10.6 GHz range has been designed as a test bed for efficiency measurements of antennas manufactured using polymer conductors. Two types of conductive polymers, PEDOT and PPy (polypyrrole), with very different thicknesses and conductivities have been selected as conductors for the radiating elements. A comparison between measured radiation patterns of the conductive polymers and a copper reference antenna allows to estimate the conductor losses of the two types of conductive polymers. For a 158 μm thick PPy polymer, an efficiency of almost 80% can be observed over the whole UWB spectrum. For a 7 μm thick PEDOT layer, an average efficiency of 26.6% demonstrates, considering the room for improvement, the potential of this type of versatile materials as flexible printable alternative to conductive metallic paints. The paper demonstrates that, even though the PEDOT conductivity is an order of magnitude larger than that of PPy, the thicker PPy layer leads to much higher efficiency over the whole UWB frequency range. This result highlights that high efficiency can be achieved not only through high conductivity, but also through a sufficiently thick layer of conductive polymers.

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Roy, Manish Kumar, Ishwer Shivakoti, Ruben Phipon, and Ashis Sharma. "A Holistic Approach to Polymeric Material Selection for Laser Beam Machining using Methods of DEA and TOPSIS." Foundations of Computing and Decision Sciences 45, no. 4 (December 1, 2020): 339–57. http://dx.doi.org/10.2478/fcds-2020-0017.

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AbstractLaser Beam machining (LBM) nowadays finds a wide acceptance for cutting various materials and cutting of polymer sheets is no exception. Greater reliability of process coupled with superior quality of finished product makes LBM widely used for cutting polymeric materials. Earlier researchers investigated the carbon dioxide laser cutting to a few thermoplastic polymers in thickness varying from 2mm to 10mm. Here, an approach is being made for grading the suitability of polymeric materials and to answer the problem of selection for LBM cutting as per their weightages obtained by using multi-decision making (MCDM) approach. An attempt has also been made to validate the result thus obtained with the experimental results obtained by previous researchers. The analysis encompasses the use of non-parametric linear-programming method of data envelopment analysis (DEA) for process efficiency assessment combined with technique for order preference by similarity to an ideal solution (TOPSIS) for selection of polymer sheets, which is based on the closeness values. The results of this uniquely blended analysis reflect that for 3mm thick polymer sheet is polypropelene (PP) to be highly preferable over polyethylene (PE) and polycarbonate (PC). While it turns out to be that polycarbonate (PC) to be highly preferable to other two polymers for 5mm thick polymer sheets. Hence the present research analysis fits very good for the polymer sheets of 3mm thickness while it deviates a little bit for the 5mm sheets.

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Fazi, Laura, Carla Andreani, Cadia D’Ottavi, Leonardo Duranti, Pietro Morales, Enrico Preziosi, Anna Prioriello, et al. "Characterization of Conductive Carbon Nanotubes/Polymer Composites for Stretchable Sensors and Transducers." Molecules 28, no. 4 (February 13, 2023): 1764. http://dx.doi.org/10.3390/molecules28041764.

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The increasing interest in stretchable conductive composite materials, that can be versatile and suitable for wide-ranging application, has sparked a growing demand for studies of scalable fabrication techniques and specifically tailored geometries. Thanks to the combination of the conductivity and robustness of carbon nanotube (CNT) materials with the viscoelastic properties of polymer films, in particular their stretchability, “surface composites” made of a CNT on polymeric films are a promising way to obtain a low-cost, conductive, elastic, moldable, and patternable material. The use of polymers selected for specific applications, however, requires targeted studies to deeply understand the interface interactions between a CNT and the surface of such polymer films, and in particular the stability and durability of a CNT grafting onto the polymer itself. Here, we present an investigation of the interface properties for a selected group of polymer film substrates with different viscoelastic properties by means of a series of different and complementary experimental techniques. Specifically, we studied the interaction of a single-wall carbon nanotube (SWCNT) deposited on two couples of different polymeric substrates, each one chosen as representative of thermoplastic polymers (i.e., low-density polyethylene (LDPE) and polypropylene (PP)) and thermosetting elastomers (i.e., polyisoprene (PI) and polydimethylsiloxane (PDMS)), respectively. Our results demonstrate that the characteristics of the interface significantly differ for the two classes of polymers with a deeper penetration (up to about 100 μm) into the polymer bulk for the thermosetting substrates. Consequently, the resistance per unit length varies in different ranges, from 1–10 kΩ/cm for typical thermoplastic composite devices (30 μm thick and 2 mm wide) to 0.5–3 MΩ/cm for typical thermosetting elastomer devices (150 μm thick and 2 mm wide). For these reasons, the composites show the different mechanical and electrical responses, therefore suggesting different areas of application of the devices based on such materials.

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Zhang, Afang, Junji Sakamoto, and Dieter A. Schlüter. "Polymers Going Rigid, Thick, and Laterally Infinite." CHIMIA International Journal for Chemistry 62, no. 10 (October 29, 2008): 776–82. http://dx.doi.org/10.2533/chimia.2008.776.

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Glovnea, R. P., A. V. Olver, and H. A. Spikes. "Lubrication of Rough Surfaces by a Boundary Film-Forming Viscosity Modifier Additive." Journal of Tribology 127, no. 1 (January 1, 2005): 223–29. http://dx.doi.org/10.1115/1.1828069.

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In previous work it was shown that some functionalized polymers used as viscosity index improvers are able to form thick boundary lubricating films. This behavior results from adsorption of the polymer on metal surfaces to form a layer of enhanced viscosity adjacent to the surface. In the current work the behavior of one such polymer in rough surface contact conditions is studied, using both model and real rough surfaces. It is found that the polymer is able to form a thick boundary film in rough surface contact, just as it does with smooth surfaces. It is also shown that the effect of this boundary film is to significantly reduce friction in rolling-sliding, rough surface, lubricated contact.

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Reneker, Darrell H., Rajkumari Patil, Seog J. Kim, and Vladimir Tsukruk. "Scanning-probe microscopy of polymers." Proceedings, annual meeting, Electron Microscopy Society of America 51 (August 1, 1993): 874–75. http://dx.doi.org/10.1017/s0424820100150204.

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Scanning probe microscopy techniques, particularly atomic force microscopy (AFM) and scanning tunneling microscopy (STM) are finding a rapidly growing number of applications to both synthetic and biological polymers. Segments of individual polymer molecules can often be observed with atom scale resolution. Observation of polymeric objects as large as 100 microns with nanometer resolution is possible with contemporary AFM, although features caused by the convolution of the shape of the sample and the shape of the tip must be recognized and properly interpreted. The vertical resolution of the atomic force microscope readily provides precise data about the heights of molecules, crystals, and other objects.Lamellar crystals of polyethylene are well characterized objects with many features which can be observed with scanning probe microscopes. Figure 1 shows the fold surface near a fold domain boundary of a lamellar crystal of polyethylene, as observed with an AFM. The folded chain crystal is about 15 nm thick.

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Gaikwad, Ravi, Xunchen Liu, Priyesh Dhandharia, and Thomas Thundat. "Investigation of Polymer Dendritic Growth in Composite Material using Contact Resonance Method." MRS Proceedings 1754 (2015): 61–67. http://dx.doi.org/10.1557/opl.2015.217.

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ABSTRACTA special class of polymer called dendrons which are repeatedly branched polymers linked together by a network of cascade branched monomers. A composite of these dendritic polymers with linear polymers may have unique physical and chemical properties. Using contact resonance mode of atomic force microscopy we are able to detect the viscoelastic properties of the dendritic formation of the polyethylene oxide (PEO) mixed with Polyvinylpyrrolidone (PVP). PEO is known to form nanometric crystallites due to the diffusion limited aggregation process. However, the dendritic formation in the mixture has not been reported before. The amplitude and phase of the contact resonance shows a clear dendritic growth of PEO in the composite material. The extent of the polymer crystallization can be several nanometers thick within the composite material. Additionally, the intrinsic properties of such polymers to form denrimers can be explored for fabricating polymer composites having numerous potential applications in chemical sensing, drug-delivery, energy applications and many more.

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Griehl, Stefan, Tobias Müller, and Rolf Winkler. "Thick metallization-layers on polymers through vacuum-technology." Surface and Coatings Technology 169-170 (June 2003): 24–26. http://dx.doi.org/10.1016/s0257-8972(03)00055-0.

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Wakahara, Takatsugu, Kun’ichi Miyazawa, Osamu Ito, and Nobutaka Tanigaki. "Preparation of Composite Films of a Conjugated Polymer and C60NWs and Their Photovoltaic Application." Journal of Nanomaterials 2016 (2016): 1–5. http://dx.doi.org/10.1155/2016/2895850.

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Composite films of conjugated polymers, such as poly[2-methoxy-5-(3′,7′-dimethyloctyloxy)-1,4-phenylenevinylene] (MDMO-PPV) and poly(3-hexylthiophene) (P3HT), with C60nanowhiskers (C60NWs) were prepared. The photoluminescence originating from the conjugated MDMO-PPV polymers was effectively quenched in the composite film, indicating a strong interaction between the conjugated polymer and C60NWs. The photovoltaic devices were fabricated using C60NW (conjugated polymer) composite films, resulting in a power conversion efficiency of ~0.01% for P3HT with short length thin C60NWs, which is higher than that previously reported for thick C60nanorods. The present study gives new guidance on the selection of the type of C60NWs and the appropriate polymer for new photovoltaic devices.

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Sakuma, Wataru, Shuji Fujisawa, Lars A. Berglund, and Tsuguyuki Saito. "Nanocellulose Xerogel as Template for Transparent, Thick, Flame-Retardant Polymer Nanocomposites." Nanomaterials 11, no. 11 (November 12, 2021): 3032. http://dx.doi.org/10.3390/nano11113032.

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Cellulose nanofibers (CNFs) have excellent properties, such as high strength, high specific surface areas (SSA), and low coefficients of thermal expansion (CTE), making them a promising candidate for bio-based reinforcing fillers of polymers. A challenge in the field of CNF-reinforced composite research is to produce strong and transparent CNF/polymer composites that are sufficiently thick for use as load-bearing structural materials. In this study, we successfully prepared millimeter-thick, transparent CNF/polymer composites using CNF xerogels, with high porosity (~70%) and high SSA (~350 m2 g−1), as a template for monomer impregnation. A methacrylate was used as the monomer and was cured by UV irradiation after impregnation into the CNF xerogels. The CNF xerogels effectively reinforced the methacrylate polymer matrix, resulting in an improvement in the flexural modulus (up to 546%) and a reduction in the CTE value (up to 78%) while maintaining the optical transparency of the matrix polymer. Interestingly, the composites exhibited flame retardancy at high CNF loading. These unique features highlight the applicability of CNF xerogels as a reinforcing template for producing multifunctional and load-bearing polymer composites.

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Lv, Tian, Jing Chun Wu, Fang Shi, and Yang Zhao. "Screening of Polymer-Producing Bacteria for Microbial Combination Flooding in Thick Oilfield." Applied Mechanics and Materials 733 (February 2015): 27–30. http://dx.doi.org/10.4028/www.scientific.net/amm.733.27.

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Through the cultivation of two polymer-producing strains of WP1, SP1, determined the suitable growth temperature of bacteria, followed by fermented, we research the growth of the strains and metabolite changes on viscosity and pH values. Results show that at 80 r/min, 120 r/min training conditions, viscosity of strain WP1 is all more than 100mPa•s, the strains of experimental works better than SP1. Therefore, selected strain WP1 identified as strains of microorganisms in thick oilfield combination flooding produced polymers, this strain is identified at last.

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Henning, Carolin, Anna Schmid, Sophia Hecht, Kathrin Harre, and Reinhard Bauer. "Applicability of Different Bio-based Polymers for Wiring Boards." Periodica Polytechnica Electrical Engineering and Computer Science 63, no. 1 (February 15, 2019): 1–8. http://dx.doi.org/10.3311/ppee.13431.

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The paper gives a review of experiments for the application of biodegradable, sustainable polymers as a wiring board material. In the paper two different biobased materials and the standard PCB materials FR4 and FR2 were compared. The investigations refer to mechanical, electrical performance, surface quality the flammability and applicability for Polymer Thick Film Technology (PTFT) of the biobased material. The biobased materials are polylactic acid (PLA) mixed with different contents of cellulose acetate (CA) or flame retardant zinc pyrophosphate (ZnPP) and polyurethane (PU) with CA. The results show that the addition of CA to the polymers leads to a change of different properties for PLA and to a significant change in mechanical properties for PU. The use of ZnPP in PLA shows major improvements regarding the flammability of the polymer. The properties of the samples are in the same order of magnitude as the properties of FR2.

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Yazyev, Serdar B., Stepan Litvinov, Anastasia E. Dudnik, and Irina Doronkina. "Rheological Aspects of Multilayered Thick-Wall Polymeric Pipes under the Influence of Internal Pressure." Key Engineering Materials 869 (October 2020): 209–17. http://dx.doi.org/10.4028/www.scientific.net/kem.869.209.

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Rheologic of a polymer pipe from cyclic temperature and internal pressure in one-dimensional and two-dimensional formulations is considered. The resulting equations of the finite element method allow one to calculate both single-layer and multilayer thick-walled pipes taking into account creep. In the calculation, the temperature dependences of the elastic and rheological parameters of polymer pipes were used. The effect of variable thermal conditions on the VAT of a PVC pipe is investigated. It has been established that under unsteady thermal conditions, stresses can occur significantly higher than in a stationary temperature field. This is explained by the fact that polymers have a component of deformation that is lagging in phase from stresses (highly elastic deformation).

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De Caro, Liberato, Francesco Scattarella, Davide Altamura, Milena P. Arciniegas, Dritan Siliqi, Liberato Manna, and Cinzia Giannini. "X-ray ptychographic mode of self-assembled CdSe/CdS octapod-shaped nanocrystals in thick polymers." Journal of Applied Crystallography 53, no. 3 (May 27, 2020): 741–47. http://dx.doi.org/10.1107/s160057672000583x.

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This work describes the application of X-ray ptychography for the inspection of complex assemblies of highly anisotropic nanocrystals embedded in a thick polymer matrix. More specifically, this case deals with CdSe/CdS octapods, with pod length L = 39 ± 2 nm and pod diameter D = 12 ± 2 nm, dispersed in free-standing thick films (24 ± 4 µm) of polymethyl methacrylate and polystyrene, with different molecular weights. Ptychography is the only imaging method available to date that can be used to study architectures made by these types of nanocrystals in thick polymeric films, as any other alternative direct method, such as scanning/transmission electron microscopy, can be definitively ruled out as a result of the large thickness of the free-standing films. The electron density maps of the investigated samples are reconstructed by combining iterative difference map algorithms and a maximum likelihood optimization algorithm. In addition, post image processing techniques are applied to both reduce noise and provide a better visualization of the material morphological details. Through this process, at a final resolution of 27 nm, the reconstructed maps allow us to visualize the intricate network of octapods inside the polymeric matrices.

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Sassin, Megan B., Jeffrey W. Long, Jean Marie Wallace, and Debra R. Rolison. "Routes to 3D conformal solid-state dielectric polymers: electrodeposition versus initiated chemical vapor deposition." Materials Horizons 2, no. 5 (2015): 502–8. http://dx.doi.org/10.1039/c5mh00057b.

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We show that two distinct methods, electropolymerization and initiated chemical vapour deposition (iCVD), can be adapted to generate ultrathin polymers (30–50 nm thick) at three dimensionally (3D) porous conductive substrates comprising ∼300 μm-thick carbon-coated silica fiber paper (C@SiO₂).

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Ashrafi, Hosein, M. R. Bahadori, and M. Shariyat. "Modeling of Viscoelastic Solid Polymers Using a Boundary Element Formulation with Considering a Body Load." Advanced Materials Research 463-464 (February 2012): 499–504. http://dx.doi.org/10.4028/www.scientific.net/amr.463-464.499.

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In this work, a boundary element formulation for 2D linear viscoelastic solid polymers subjected to body force of gravity has been presented. Structural analysis of solid polymers is one of the most important subjects in advanced engineering structures. From basic assumptions of the viscoelastic constitutive equations and the weighted residual techniques, a simple but effective boundary element formulation is implemented for standard linear solid (SLS) model. The SLS model provides an approximate representation of observed behavior of a real advanced polymer in its viscoelastic range. This approach avoids the use of relaxation functions and mathematical transformations, and it is able to solve quasistatic viscoelastic problems with any load time-dependence and boundary conditions. Problem of pressurization of thick-walled viscoelastic tanks made of PMMA polymer, which subjected to a body force, is completely analyzed.

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Pavia, F. Carfì, V. Brucato, M. C. Mistretta, L. Botta, and F. P. La Mantia. "A Biodegradable, Bio-Based Polymer for the Production of Tools for Aquaculture: Processing, Properties and Biodegradation in Sea Water." Polymers 15, no. 4 (February 13, 2023): 927. http://dx.doi.org/10.3390/polym15040927.

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Bio-based, biodegradable polymers can dramatically reduce the carbon dioxide released into the environment by substituting fossil-derived polymers in some applications. In this work, prototypes of trays for aquaculture applications were produced via injection molding by using a biodegradable polymer, Mater-Bi®. A characterization carried out via calorimetric, rheological and mechanical tests revealed that the polymer employed shows properties suitable for the production of tools to be used in aquaculture applications. Moreover, the samples were subjected to a biodegradation test in conditions that simulate the marine environment. The as-treated samples were characterized from gravimetrical, morphological and calorimetric point of views. The obtained data showed a relatively low biodegradation rate of the thick molded samples. This behavior is of crucial importance since it implies a long life in marine water for these manufacts before their disappearing.

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Mutlu, Mustafa Umut, Osman Akin, Mustafa M. Demir, and Ümit Hakan Yildiz. "Fabrication of Polymer Nanofiber-Conducting Polymer Fabric and Noncontact Motion Sensing Platform." Materials Science Forum 915 (March 2018): 207–12. http://dx.doi.org/10.4028/www.scientific.net/msf.915.207.

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Conductive polymer-electrospun polymer nanofiber network was combined to host iron oxide nanoparticles providing micrometer thick sensing interface. The sensor has fabricated as free-standing fabric exhibiting 10 to 100 KOhm base resistivity upon bias applied. The moving object has been sensed through the electrostatic interactions between fibers and object. The sensing range has been found to be 1-5 cm above the surface of fabric. By the controlled combination of conductive polymers electrospun polymer nanofibers effective device miniaturization has been provided without loss of performance. The noncontact motion sensor platform has unique flexibility and light weight holding a potential for wearable sensor technology.

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Singh, Akanksha, Gianmario Scotti, Tiina Sikanen, Ville Jokinen, and Sami Franssila. "Laser Direct Writing of Thick Hybrid Polymers for Microfluidic Chips." Micromachines 5, no. 3 (July 22, 2014): 472–85. http://dx.doi.org/10.3390/mi5030472.

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Jones, Austin L., Carr Hoi Yi Ho, Parand R. Riley, Indunil Angunawela, Harald Ade, Franky So, and John R. Reynolds. "Investigating the active layer thickness dependence of non-fullerene organic solar cells based on PM7 derivatives." Journal of Materials Chemistry C 8, no. 43 (2020): 15459–69. http://dx.doi.org/10.1039/d0tc03096a.

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This work exposes the importance of testing a polymers active layer thickness tolerance as small modifications to a polymers structure can radically change its ability to stack/pack in the BHJ which is reflected in thick active layer OSCs.

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Suh, Seigi, Ryan Persons, Doug Hargrove, and Gregory Berube. "Solderable Polymer Thick-film Conductors for Low Temperature Substrates." International Symposium on Microelectronics 2018, no. 1 (October 1, 2018): 000310–16. http://dx.doi.org/10.4071/2380-4505-2018.1.000310.

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Abstract For decades, polymer thick-film (PTF) systems have provided a low cost, non-fired option for screen-printing simple electronic circuits. The ability to apply these types of pastes on temperature sensitive substrates such as PET, polycarbonate, polyimide, and other polymers has facilitated a variety of applications, for instance membrane touch-switch keypads, buss bars for touch screens, various types of sensors, and flexible circuitry. Polymer thick-film is also one of the primary technology solutions utilized in the rapidly emerging Printed Electronic market, where flexible, durable materials are paramount to the success of these technologies. One of the largest emerging markets for polymer thick-film is wearable electronics, where engineers are designing “smart fabrics” with active circuitry for medical monitoring, performance enhancement in sports, and personal comfort. Polymer thick-film pastes include silver pastes for conductors, carbon pastes for resistive applications, silver-silver chloride fillers for glucose sensors, and dielectric pastes. The major challenge with PTF silver conductors is that they are not conducive to soldering. This hinders the ability to attach components, leads, dies, wires, or other features to the prints. As copper is solderable, one possible solution would be a copper polymer thick-film metallization; however they start oxidizing at the typical paste curing temperatures, 110 – 130°C, rendering them unsuitable for the vast majority of conductive applications. In order to meet these challenges, Heraeus has developed a new line of solderable polymer thick-film conductors based on a high-performance silver-coated copper conductive filler. These metallizations are solderable, resistant to solder leaching, and result in sheet resistivities approaching that of pure silver polymer conductors. The prints do not degrade in performance when cured at temperatures as high as 200°C. The new product line was formulated to accept different types of solders, especially traditional SAC-305, which provides a complete matched solution for designers. The new metallization opens up new applications given its ability to print polymer circuitry on a variety of substrates including aluminum, steel, FR4, Kapton, Mylar, and glass. The technology also allows for the fabrication of more complex circuitry on these types of substrates, giving circuit designers a powerful new tool in their toolbox in applications such as LED lighting, sensors, and heaters. Finally, these materials may provide a lower-cost option for solderable flexible polymer end terminations for components used in vibration sensitive applications, for instance the automotive industry. In our paper, we will present the properties of the new pastes and printed conductors. Performance testing includes surface resistivity, solderability, solder leach resistance, voiding, and adhesion on two substrates: FR4 and Kapton. Furthermore, we show that the solderable PTF conductor will provide a potential cost- savings over the current technology used on FR4 boards, stamped copper films. By replacing the stamped copper with our solderable PTF conductor, manufacturers will have the advantage of replacing a subtractive process for etching their patterns with an additive, environmentally friendly process, not only saving processing time but eliminating a large, dangerous copper waste stream. Finally, we will summarize the applications that the new technology enables.

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Li, Kebin, Javier Alejandro Hernández-Castro, Keith Morton, and Teodor Veres. "Facile Fabrication of Flexible Polymeric Membranes with Micro and Nano Apertures over Large Areas." Polymers 14, no. 19 (October 9, 2022): 4228. http://dx.doi.org/10.3390/polym14194228.

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Freestanding, flexible and open through-hole polymeric micro- and nanostructured membranes were successfully fabricated over large areas (>16 cm2) via solvent removal of sacrificial scaffolds filled with polymer resin by spontaneous capillary flow. Most of the polymeric membranes were obtained through a rapid UV curing processes via cationic or free radical UV polymerisation. Free standing microstructured membranes were fabricated across a range of curable polymer materials, including: EBECRYL3708 (radical UV polymerisation), CUVR1534 (cationic UV polymerisation) UV lacquer, fluorinated perfluoropolyether urethane methacrylate UV resin (MD700), optical adhesive UV resin with high refractive index (NOA84) and medical adhesive UV resin (1161-M). The present method was also extended to make a thermal set polydimethylsiloxane (PDMS) membranes. The pore sizes for the as-fabricated membranes ranged from 100 µm down to 200 nm and membrane thickness could be varied from 100 µm down to 10 µm. Aspect ratios as high as 16.7 were achieved for the 100 µm thick membranes for pore diameters of approximately 6 µm. Wide-area and uniform, open through-hole 30 µm thick membranes with 15 µm pore size were fabricated over 44 × 44 mm2 areas. As an application example, arrays of Au nanodots and Pd nanodots, as small as 130 nm, were deposited on Si substrates using a nanoaperture polymer through-hole membrane as a stencil.

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Ahmad Sobri, Sharizal, Robert Heinemann, and David Whitehead. "Sequential Laser–Mechanical Drilling of Thick Carbon Fibre Reinforced Polymer Composites (CFRP) for Industrial Applications." Polymers 13, no. 13 (June 29, 2021): 2136. http://dx.doi.org/10.3390/polym13132136.

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Carbon fibre reinforced polymer composites (CFRPs) can be costly to manufacture, but they are typically used anywhere a high strength-to-weight ratio and a high steadiness (rigidity) are needed in many industrial applications, particularly in aerospace. Drilling composites with a laser tends to be a feasible method since one of the composite phases is often in the form of a polymer, and polymers in general have a very high absorption coefficient for infrared radiation. The feasibility of sequential laser–mechanical drilling for a thick CFRP is discussed in this article. A 1 kW fibre laser was chosen as a pre-drilling instrument (or initial stage), and mechanical drilling was the final step. The sequential drilling method dropped the overall thrust and torque by an average of 61%, which greatly increased the productivity and reduced the mechanical stress on the cutting tool while also increasing the lifespan of the bit. The sequential drilling (i.e., laser 8 mm and mechanical 8 mm) for both drill bits (i.e., 2- and 3-flute uncoated tungsten carbide) and the laser pre-drilling techniques has demonstrated the highest delamination factor (SFDSR) ratios. A new laser–mechanical sequence drilling technique is thus established, assessed, and tested when thick CFRP composites are drilled.

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Zhang, Na, Taisheng Wang, Xing Wu, Chen Jiang, Taiming Zhang, Bangkun Jin, Hengxing Ji, Wei Bai, and Ruke Bai. "From 1D Polymers to 2D Polymers: Preparation of Free-Standing Single-Monomer-Thick Two-Dimensional Conjugated Polymers in Water." ACS Nano 11, no. 7 (June 24, 2017): 7223–29. http://dx.doi.org/10.1021/acsnano.7b03109.

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Nguyen, T. L., H. Choi, S. J. Ko, M. A. Uddin, B. Walker, S. Yum, J. E. Jeong, et al. "Semi-crystalline photovoltaic polymers with efficiency exceeding 9% in a ∼300 nm thick conventional single-cell device." Energy Environ. Sci. 7, no. 9 (2014): 3040–51. http://dx.doi.org/10.1039/c4ee01529k.

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Li, Yuxiang, Seo-Jin Ko, Song Yi Park, Hyosung Choi, Thanh Luan Nguyen, Mohammad Afsar Uddin, Taehyo Kim, Sungu Hwang, Jin Young Kim, and Han Young Woo. "Quinoxaline–thiophene based thick photovoltaic devices with an efficiency of ∼8%." Journal of Materials Chemistry A 4, no. 25 (2016): 9967–76. http://dx.doi.org/10.1039/c6ta03801h.

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Liu, Tong, Lanting Ji, Guobing He, Xiaoqiang Sun, Fei Wang, and Daming Zhang. "Ultrathin Au film on polymer surface for surface plasmon polariton waveguide application." Modern Physics Letters B 31, no. 32 (November 19, 2017): 1750300. http://dx.doi.org/10.1142/s0217984917503006.

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Formation of laterally continuous ultrathin gold films on polymer substrates is a technological challenge. In this work, the vacuum thermal evaporation method is adopted to form continuous Au films in the thickness range of 7–17 nm on polymers of Poly(methyl-methacrylate-glycidly-methacrylate) and SU-8 film surface without using the adhesion or metallic seeding layers. Absorption spectrum, scanning electron microscope and atomic force microscope images are used to characterize the Au film thickness, roughness and optical loss. The result shows that molecular-scale structure, surface energy and electronegativity have impacts on the Au film morphology on polymers. Wet chemical etching is used to fabricate 7-nm thick Au stripes embedded in polymer claddings. These long-range surface plasmon polariton waveguides demonstrate the favorable morphological configurations and cross-sectional states. Through the end-fire excitation method, propagation losses of 6-[Formula: see text] wide Au stripes are compared to theoretical values and analyzed from practical film status. The smooth, patternable gold films on polymer provide potential applications to plasmonic waveguides, biosensing, metamaterials and optical antennas.

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Rantuch, Peter, Jozef Martinka, Tomáš Štefko, and Igor Wachter. "Initiation Parameters of Granulated Synthetic Polymers." Research Papers Faculty of Materials Science and Technology Slovak University of Technology 29, no. 48 (June 1, 2021): 114–22. http://dx.doi.org/10.2478/rput-2021-0012.

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Abstract Polymeric materials, which are currently very often used in various industries, are often transported and stored in the form of granules before processing. This method has several advantages, but in most studies the test samples are modified to different shapes and dimensions. This paper is therefore focused on the initiation of selected granular plastics. Samples of five polymeric materials were exposed to an external heat flux from 20 kW.m−2 to 40 kW.m−2. A spark initiator was used to ignite the released gaseous products of thermal decomposition of the polymer sample. FTP (flow-time product) method was applied to the obtained parameter - time to ignition, from which other initiation parameters were determined. The critical heat flux was determined in the range of 5.0 kW.m−2 - 11.8 kW.m−2. Despite the relatively small thickness (4 mm), the samples behaved as thermally thick. During the measurement, thin surface layer melted, and the rest of the polymer remained in its original granulated form. Ignition temperatures were calculated according to the Stefan-Boltzmann’s law between 273 °C - 402 °C.

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Liu, Jie, Xiacong Zhang, Xiao Chen, Liangliang Qu, Liyuan Zhang, Wen Li, and Afang Zhang. "Stimuli-responsive dendronized polymeric hydrogels through Schiff-base chemistry showing remarkable topological effects." Polymer Chemistry 9, no. 3 (2018): 378–87. http://dx.doi.org/10.1039/c7py01865g.

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Закревский, В. А., В. А. Пахотин, and Н. Т. Сударь. "Влияние крутизны фронта импульса напряжения на электрическую прочность полимеров." Журнал технической физики 89, no. 1 (2019): 120. http://dx.doi.org/10.21883/jtf.2019.01.46972.98-18.

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AbstractWe have studied the effect of the leading edge steepness of a high-voltage pulse front on the dielectric strength of 3-μm-thick polyethylene terephthalate film. It is found that its breakdown electric field strength increases logarithmically from 550 to 700 MV/m upon an increase in the voltage growth rate (pulse front steepness) from 2 to 70 GV/s. It is shown that the experimental data can be described using the concept of the ionization mechanism of polymer breakdown, which is not associated with the evolution of impact ionization in polymers, and accounting for the decrease in the overvoltage coefficient in a polymer dielectric upon an increase in the pulse front steepness.

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Guangteng, G., M. Smeeth, P. M. Cann, and H. A. Spikes. "Measurement and Modelling of Boundary Film Properties of Polymeric Lubricant Additives." Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology 210, no. 1 (March 1996): 1–15. http://dx.doi.org/10.1243/pime_proc_1996_210_473_02.

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Experimental work using ultrathin film interferometry has shown that some polymer solutions in oil form much thicker films at slow speeds in rolling, concentrated contacts than predicted from elastohydrodynamic (EHD) theory. This behaviour can be interpreted as resulting from the polymers forming adsorbed, surface layers of enhanced concentration on the two solid surfaces. Such layers, which are typically 20 nm thick, would be significantly more viscous that the bulk solution and thus produce thicker EHD films. This concept has been supported by modelling the elastohydrodynamic point contact using control volume analysis with a layered surface viscosity. The film thickness behaviour predicted computationally using this technique is quite similar to that found experimentally using polymer solutions.

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Zafar, Adeel, Mokhtar Awang, Sajjad Raza Khan, and Sattar Emamian. "Effect of Double Shoulder Tool Rotational Speed on Thermo-Physical Characteristics of Friction Stir Welded 16mm Thick Nylon6." Applied Mechanics and Materials 799-800 (October 2015): 251–55. http://dx.doi.org/10.4028/www.scientific.net/amm.799-800.251.

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Friction stir welding (FSW) of polymers is relatively a new concept among modern polymer joining techniques. This study demonstrates the applicability of FSW on 16mm thick nylon-6 plates at constant welding rate of 25mm/min and varying rotational speed between 300 to 1000RPM. A special designed tool was fabricated which has double shoulder and right-hand threaded pin profile. It has shown excellent results at relatively lower rotation speeds. Visual inspection and microstructural examination of cross sections showed that the cavities and tunnel defects appeared only at higher rotational speeds. A linear relationship was observed between temperature and rotation speed.

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Kausar, Ayesha, Ishaq Ahmad, M. H. Eisa, and Malik Maaza. "Graphene Nanocomposites in Space Sector—Fundamentals and Advancements." C 9, no. 1 (March 3, 2023): 29. http://dx.doi.org/10.3390/c9010029.

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Graphene is one of the most significant carbon nanomaterials, with a one-atom-thick two-dimensional nanostructure. Like other nanocarbons, graphene has been used as a polymer reinforcement. This review explores the impact of graphene and graphene-based nanocomposites on aerospace applications. The fabrication and indispensable features of graphene-derived nanocomposites have been considered. Numerous polymers and nanocomposites have been employed for aerospace systems such as reinforced thermosetting/thermoplastic polymers and epoxy/graphene nanocomposites. Moreover, graphene-modified carbon-fiber-based composites have been discussed for the space sector. Aerospace nanocomposites with graphene have been investigated for superior processability, structural features, morphology, heat stability, mechanical properties, flame resistance, electrical/thermal conductivity, radiation protection, and adhesion applications. Subsequently, epoxy and graphene-derived nanocomposites have been explored for heat/mechanically stable aerospace engineering structures, radiation-shielding materials, adhesives, coatings, etc.

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Lim, Seongsik, Vivek Kumar Dhimole, Yongbae Kim, and Chongdu Cho. "Investigations for Design Estimation of an Anisotropic Polymer Matrix Composite Plate with a Central Circular Hole under Uniaxial Tension." Polymers 14, no. 10 (May 12, 2022): 1977. http://dx.doi.org/10.3390/polym14101977.

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Composite plates with holes are common in engineering applications, such as the automotive and aerospace industries. Three-dimensional braided carbon/epoxy polymers are an advanced textile composite and are used in various structures due to their high damage resistance and relatively low manufacturing cost. When a braided polymer plate with a hole is used in engineering applications, it is necessary to know its mechanical behavior under loading conditions using analysis theory to design it better. However, the effects of stress distribution with shear deformation theories on the variable thickness of the braided polymer plate (carbon/epoxy) with a hole under tensile loading have not been reported yet. In this paper, a study is conducted to evaluate shear deformation theories for a braided polymer plate with variable thickness and a hole in the center, analyzing the stresses and their concentration variations. First, multiscale modeling and analysis are performed to determine the mechanical properties of the plate. Then, finite element analyses are performed on a homogenized macro plate with a hole. The analysis process is verified by comparison with the available literature. Results show that the first-order shear deformation theory calculates 37, 56, and 70 percent less maximum transverse shear stress than the high-order shear deformation theory (Reissner–Mindlin) and the elasticity theory for thin, moderately thick, and thick braided polymer plates, respectively. Additionally, changing the theory has no significant effect on circumferential stress, radial stress, Von Mises stress, and stress concentration factor. As a result, this research can provide researchers and designers with structural intuition for a braided polymer plate with a center hole.

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Malara, Angela, Lucio Bonaccorsi, Antonio Fotia, Pier Luigi Antonucci, and Patrizia Frontera. "Hybrid Fluoro-Based Polymers/Graphite Foil for H2/Natural Gas Separation." Materials 16, no. 5 (March 5, 2023): 2105. http://dx.doi.org/10.3390/ma16052105.

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Membrane technologies and materials development appear crucial for the hydrogen/natural gas separation in the impending transition to the hydrogen economy. Transporting hydrogen through the existing natural gas network could result less expensive than a brand-new pipe system. Currently, many studies are focused on the development of novel structured materials for gas separation applications, including the combination of various kind of additives in polymeric matrix. Numerous gas pairs have been investigated and the gas transport mechanism in those membranes has been elucidated. However, the selective separation of high purity hydrogen from hydrogen/methane mixtures is still a big challenge and nowadays needs a great improvement to promote the transition towards more sustainable energy source. In this context, because of their remarkable properties, fluoro-based polymers, such as PVDF-HFP and NafionTM, are among the most popular membrane materials, even if a further optimization is needed. In this study, hybrid polymer-based membranes were deposited as thin films on large graphite surfaces. Different weight ratios of PVDF-HFP and NafionTM polymers supported over 200 μm thick graphite foils were tested toward hydrogen/methane gas mixture separation. Small punch tests were carried out to study the membrane mechanical behaviour, reproducing the testing conditions. Finally, the permeability and the gas separation activity of hydrogen/methane over membranes were investigated at room temperature (25 °C) and near atmospheric pressure (using a pressure difference of 1.5 bar). The best performance of the developed membranes was registered when the 4:1 polymer PVDF-HFP/NafionTM weight ratio was used. In particular, starting from the 1:1 hydrogen/methane gas mixture, a 32.6% (v%) H2 enrichment was measured. Furthermore, there was a good agreement between the experimental and theoretical selectivity values.

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Farag, Zeinab R., Jörg F. Friedrich, and Simone Krüger. "Adhesion promotion of thick fire-retardant melamine polymer dip-coatings at polyolefin surfaces by using plasma polymers." Journal of Adhesion Science and Technology 28, no. 21 (August 27, 2014): 2113–32. http://dx.doi.org/10.1080/01694243.2014.943339.

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Duan, Chunhui, Ke Gao, Fallon J. M. Colberts, Feng Liu, Stefan C. J. Meskers, Martijn M. Wienk, and René A. J. Janssen. "Thiophene Rings Improve the Device Performance of Conjugated Polymers in Polymer Solar Cells with Thick Active Layers." Advanced Energy Materials 7, no. 19 (July 10, 2017): 1700519. http://dx.doi.org/10.1002/aenm.201700519.

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40

Langer, Robert. "Biomaterials: New Polymers and Novel Applications." MRS Bulletin 20, no. 8 (August 1995): 18–22. http://dx.doi.org/10.1557/s0883769400045061.

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The following is an edited transcript of the plenary lecture presented by Robert Langer at the 1995 MRS Spring Meeting on April 17, 1995 in San Francisco.Over the last 21 years I have been involved in examining and studying, and in some cases synthesizing new polymers and biomaterials, looking at how they might be able to solve two problems. One set of problems involves drug delivery; a second involves creating new tissues.Controlled drug release is a relatively young field that has involved a fundamental change in the way drugs are delivered. Transdermal drug delivery, for example, uses five layers of polymers, yet the whole system is 0.2 mm thick. One such polymer contains nitroglycerine, which is slowly released for one day from a patch through the skin into the blood circulation. This process provided a novel way to treat angina for patients with chest pains. First introduced in 1982, such drug-delivery systems saw a usage rate of over 500 million last year.Norplant systems, which are silicone capsules placed under the forearm, slowly release a birth-control drug for over 2,000 days, or five years, from what are actually six small implants about the size of match sticks. These two examples illustrate that drugs can be made to slowly diffuse through polymers over a long period of time.

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Miller, Mark S., Bertrand C. W. Tanner, Lori R. Nyland, and Jim O. Vigoreaux. "Comparative Biomechanics of Thick Filaments and Thin Filaments with Functional Consequences for Muscle Contraction." Journal of Biomedicine and Biotechnology 2010 (2010): 1–14. http://dx.doi.org/10.1155/2010/473423.

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The scaffold of striated muscle is predominantly comprised of myosin and actin polymers known as thick filaments and thin filaments, respectively. The roles these filaments play in muscle contraction are well known, but the extent to which variations in filament mechanical properties influence muscle function is not fully understood. Here we review information on the material properties of thick filaments, thin filaments, and their primary constituents; we also discuss ways in which mechanical properties of filaments impact muscle performance.

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42

Tenchurin, Timur Kh, Alla V. Rodina, Vladimir P. Saprykin, Lada V. Gorshkova, Alexey A. Mikhutkin, Roman A. Kamyshinsky, Dmitry S. Yakovlev, Alexander L. Vasiliev, Sergey N. Chvalun, and Timofey E. Grigoriev. "The Performance of Nonwoven PLLA Scaffolds of Different Thickness for Stem Cells Seeding and Implantation." Polymers 14, no. 20 (October 15, 2022): 4352. http://dx.doi.org/10.3390/polym14204352.

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The 3D reconstruction of 100 μm- and 600 μm-thick fibrous poly-L/L-lactide scaffolds was performed by confocal laser scanning microscopy and supported by scanning electron microscopy and showed that the density of the fibers on the side adjacent to the electrode is higher, which can affect cell diffusion, while the pore size is generally the same. Bone marrow mesenchymal stem cells cultured in a 600 μm-thick scaffold formed colonies and produced conditions for cell differentiation. An in vitro study of stem cells after 7 days revealed that cell proliferation and hepatocyte growth factor release in the 600 μm-thick scaffold were higher than in the 100 μm-thick scaffold. An in vivo study of scaffolds with and without stem cells implanted subcutaneously onto the backs of recipient mice was carried out to test their biodegradation and biocompatibility over a 0–3-week period. The cells seeded onto the 600 μm-thick scaffold promoted significant neovascularization in vivo. After 3 weeks, a significant number of donor cells persisted only on the inside of the 600 μm-thick scaffold. Thus, the use of bulkier matrices allows to prolong the effect of secretion of growth factors by stem cells during implantation. These 600 μm-thick scaffolds could potentially be utilized to repair and regenerate injuries with stem cell co-culture for vascularization of implant.

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Ruan, Chunlei, and Yunlong Lv. "A Note for Probabilistic Model of Polymer Crystallization in Temperature Gradients." Crystals 9, no. 10 (October 19, 2019): 538. http://dx.doi.org/10.3390/cryst9100538.

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A polymer crystallization kinetics model is the most important way to characterize the crystallization rate of polymers. Because polymers are poor heat conductors, the cooling of thick-walled shapes results in temperature gradients. Piorkowska (Piorkowska, E. J. Appl. Polym. Sci., 2002, 86: 1351–1362.) derived the probabilistic analytical model of polymer crystallization in temperature gradients based on the Avrami equation. However, there are some misunderstandings when using this model. Here, isotactic polypropylene (iPP) is chosen as a model polymer and its crystallization is studied in a temperature gradient field. Based on the results of the Monte Carlo method, the probabilistic model methodology is discussed. The results show that when the product has a large temperature gradient and a large temperature difference, the probabilistic model cannot be used directly; instead, it is necessary to use the average probabilistic model. This means that the sample should be divided into several smaller parts and the probabilistic model used separately for each small part. The values are then averaged to obtain the mean conversion degree of the melt into spherulites for the whole product. The effects of the division number are also discussed. The goal of the present paper is to better understand the polymer crystallization kinetics model in terms of temperature gradients.

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Lee, Hye Jeong, Gopinathan Anoop, Hyeon Jun Lee, Chingu Kim, Ji-Woong Park, Jaeyoo Choi, Heesuk Kim, et al. "Enhanced thermoelectric performance of PEDOT:PSS/PANI–CSA polymer multilayer structures." Energy & Environmental Science 9, no. 9 (2016): 2806–11. http://dx.doi.org/10.1039/c5ee03063c.

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A layer-by-layer deposition of two conducting polymers, each layer of which is a few tenths of nanometer thick, has been successfully performed to enhance the thermoelectric power factor of organic thin films.

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Ji, Yaohui, Yue Qi, Rongxian Zhu, Hongxia Ma, Yahui Zhang, and Wenji Yu. "Thermophysical Molding Treatments on Thick Wood Veneer." Polymers 14, no. 17 (August 27, 2022): 3516. http://dx.doi.org/10.3390/polym14173516.

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Thermophysical molding (TPM) treatments can significantly improve the surface properties of thick wood veneer. To understand the effects of TPM treatments on the surface properties of thick veneer, the roughness, contact angles, and chemical changes were determined. The results indicated that the roughness of the thick veneer decreased when the temperature and the duration increased. The contact angles decreased when the temperature increased, resulting in better wettability. X-ray photoelectron spectroscopic (XPS) results provided information about the significant chemical changes in the surface with different TPM temperatures of 160–190 °C and durations of 5–11 min. Increases in temperature and duration increased the C content and decreased the O content during the treatment process. The most significant changes in the thick veneer that resulted from increasing the temperature and the duration were the increase in the C1 component and the decrease in the C2 component. Thus, the oxygen to carbon (O/C) ratio decreased and the ratio of aromatic carbon to aliphatic carbon (C1/C2) notably increased with the increasing TPM temperature. The TPM duration slightly affected the O/C ratio, but it had a stronger linear relation with the C1/C2 ratio. Additionally, the C1/C2 ratio and the O/C ratio had a linear statistical relationship with the initial wettability. These findings could provide useful information for the future utilization of thick veneers treated with TPM.

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Moseley, J. F. "Quick Method of Dyeing Thick Leather with Acid Dyes." Journal of the Society of Dyers and Colourists 29, no. 10 (October 22, 2008): 297–98. http://dx.doi.org/10.1111/j.1478-4408.1913.tb00688.x.

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Garber, Charles A. "Replicating The Unreplicatable." Microscopy Today 3, no. 8 (October 1995): 6–8. http://dx.doi.org/10.1017/s1551929500062866.

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When doing replication, it is very important that all traces of the sample be removed from the replica. Adhering sample material introduces artifacts into the image and may, in extreme cases, make the replica so thick that the TEM beam cannot “see” through it. This may be a problem for both “ordinary” Pt/C replicas and freeze fracture situations. For organic samples, including both biological materials and polymers. For example, polymer latex particle fragments have a particular tendency to stick to the replica in freeze fracture preparations. Some freeze fracture samples will “wet” the replica surface if the replica is stripped by melting the substrate.

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Liu, Renwei, Suna Fan, Dongdong Xiao, Jin Zhang, Mengzhou Liao, Shansheng Yu, Fanling Meng, et al. "Free-Standing Single-Molecule Thick Crystals Consisting of Linear Long-Chain Polymers." Nano Letters 17, no. 3 (February 16, 2017): 1655–59. http://dx.doi.org/10.1021/acs.nanolett.6b04896.

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Baghdadi, Neazar, M. Sh Zoromba, M. H. Abdel-Aziz, A. F. Al-Hossainy, M. Bassyouni, and Numan Salah. "One-Dimensional Nanocomposites Based on Polypyrrole-Carbon Nanotubes and Their Thermoelectric Performance." Polymers 13, no. 2 (January 16, 2021): 278. http://dx.doi.org/10.3390/polym13020278.

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Conducting polymers have attracted significant attention due to their easy fabrication, morphology modification, and their electrical properties. Amongst them, polypyrrole (PPy) has attractive thermoelectric (TE) properties. Engineering of this polymer in one-dimensional (1D) nanostructured form is found to enhance its TE performance. This was achieved in the present work by using multi-walled carbon nanotubes (MWCNTs) as a core template to direct the self-assembly of PPy and also to further enhance its TE performance. The growth of PPy on the sidewalls of MWCNTs was performed in an acidic medium based oxidative in situ polymerization. Various concentrations of MWCNTs within the range 1.1–14.6 wt.% were used to form the MWCNTs/PPy nanocomposites in 1D core-shell structures. The morphology and microstructure results of the produced nanocomposite samples showed that this MWCNTs were successfully coated by thick and thin layers of PPy. At low concentrations of MWCNTs, thick layers of PPy are formed. While at high concentrations thin layers are coated. The formed 1D nanocomposites have enhanced TE performance, particularly those containing higher contents of MWCNTs. The power factor and figure of merit values for the formed 1D nanocomposites recorded around 0.77 µV/mK2 and 1 × 10−3 at room temperature (RT), respectively. This enhancement was attributed to the perfect coating and good interaction between PPy and MWCNT through π–π stacking between the polymer chains and these nanotubes. These results might be useful for developing future TE materials and devices.

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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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Journal articles on the topic 'Thick polymers'

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