Journal articles: 'Polymeric masters'

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TANG, YUZHAO, XIAODONG ZHANG, JIELIN SUN, JUN HU, FENG ZHANG, and JIANHUA HE. "PEPTIDE NANOFILAMENTS USED FOR REPLICA-MOLDING: A COMBINATION OF "BOTTOM-UP" AND "TOP-DOWN"." Surface Review and Letters 14, no. 02 (April 2007): 301–7. http://dx.doi.org/10.1142/s0218625x07009396.

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A novel nanofabrication method that combines both "bottom-up" (template-assisted peptide self-assembling) and "top-down" (replica molding) techniques is introduced. A designer peptide, GAV-9 (NH2-VGGAVVAGV-CONH2), can epitaxially self-assemble into nanofilaments on the surface of mica, which is further used as the diversified masters for the application of replica molding. With in situ atomic force microscopy monitoring, several typical masters are fabricated by peptide self-assembling on the surface of mica. These masters can be easily molded into hard poly(dimethylsiloxane) surfaces, and then further replica-molded into polyurethane surfaces. The polymeric surfaces with regular 1D and 2D patterns on the nanometer scale are expected to have new applications in nanostructure's fabrication.

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Fu, Yangxi, Marcos Soldera, Wei Wang, Bogdan Voisiat, and Andrés Fabián Lasagni. "Picosecond Laser Interference Patterning of Periodical Micro-Architectures on Metallic Molds for Hot Embossing." Materials 12, no. 20 (October 18, 2019): 3409. http://dx.doi.org/10.3390/ma12203409.

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In this work, it is demonstrated that direct laser interference patterning (DLIP) is a method capable of producing microtextured metallic molds for hot embossing processes. Three different metals (Cr, Ni, and Cu), relevant for the mold production used in nanoimprinting systems, are patterned by DLIP using a picosecond laser source emitting at a 532 nm wavelength. The results show that the quality and surface topography of the produced hole-like micropatterns are determined by the laser processing parameters, such as irradiated energy density and the number of pulses. Laser-induced periodic surface structures (LIPSS) are also observed on the treated surfaces, whose shapes, periodicities, and orientations are strongly dependent on the accumulated fluence. Finally, the three structured metals are used as embossing molds to imprint microlenses on polymethyl methacrylate (PMMA) foils using an electrohydraulic press. Topographical profiles demonstrate that the obtained structures are comparable to the masters showing a satisfactory reproduction of the texture. The polymeric microlens arrays that showed the best surface homogeneity and overall quality were those embossed with the Cr molds.

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Pezzuoli, Denise, Elena Angeli, Diego Repetto, Patrizia Guida, Giuseppe Firpo, and Luca Repetto. "Increased Flexibility in Lab-on-Chip Design with a Polymer Patchwork Approach." Nanomaterials 9, no. 12 (November 25, 2019): 1678. http://dx.doi.org/10.3390/nano9121678.

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Nanofluidic structures are often the key element of many lab-on-chips for biomedical and environmental applications. The demand for these devices to be able to perform increasingly complex tasks triggers a request for increasing the performance of the fabrication methods. Soft lithography and poly(dimethylsiloxane) (PDMS) have since long been the basic ingredients for producing low-cost, biocompatible and flexible devices, replicating nanostructured masters. However, when the desired functionalities require the fabrication of shallow channels, the “roof collapse” phenomenon, that can occur when sealing the replica, can impair the device functionalities. In this study, we demonstrate that a “focused drop-casting” of h-PDMS (hard PDMS) on nanostructured regions, provides the necessary stiffness to avoid roof collapse, without increasing the probability of deep cracks formation, a drawback that shows up in the peel-off step, when h-PDMS is used all over the device area. With this new approach, we efficiently fabricate working devices with reproducible sub-100 nm structures. We verify the absence of roof collapse and deep cracks by optical microscopy and, in order to assess the advantages that are introduced by the proposed technique, the acquired images are compared with those of cracked devices, whose top layer, of h-PDMS, and with those of collapsed devices, made of standard PDMS. The geometry of the critical regions is studied by atomic force microscopy of their resin casts. The electrical resistance of the nanochannels is measured and shown to be compatible with the estimates that can be obtained from the geometry. The simplicity of the method and its reliability make it suitable for increasing the fabrication yield and reducing the costs of nanofluidic polymeric lab-on-chips.

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Hu, H.-W. "Master Curve of Creep in Polymeric Off-Axis Composite Laminates." Journal of Mechanics 22, no. 3 (September 2006): 229–34. http://dx.doi.org/10.1017/s1727719100000873.

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AbstractAn approach to establish a master curve for effective creep compliances of polymeric off-axis composites with various fiber orientations was presented. Carbon/epoxy composite IM7/977–3 was used to fabricate four types of off-axis specimens and then subjected to momentary creep tests after a period of initial aging. Creep compliance and elastic compliance were separated from the total compliance. Using one-parameter creep potential theory, creep compliances were transformed to effective creep compliances. After choosing a proper value for the one-parameter, all effective creep compliances with various off-axis fiber orientations were superposed into a master curve. This master curve enables us to obtain creep compliance with any off-axis fiber orientation by testing only one off-axis specimen.

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Nega, Ainalem, Behzad Ghadimi, and Hamid Nikraz. "Developing Master Curves, Binder Viscosity and Predicting Dynamic Modulus of Polymer-Modified Asphalt Mixtures." International Journal of Engineering and Technology 7, no. 3 (June 2015): 190–97. http://dx.doi.org/10.7763/ijet.2015.v7.790.

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Hsu, Fang Chang, In Chung Wu, and Chi Ting Ho. "Fabrication of a Polymeric Ridge Waveguide Filter Using a Replication Process." Applied Mechanics and Materials 321-324 (June 2013): 443–46. http://dx.doi.org/10.4028/www.scientific.net/amm.321-324.443.

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The traditional wavelength filter only have one face of grating, the gratings length must be long enough to obtain good filtering result, so the filter device can not be made to a small size. We describe a procedure for rapidly and conveniently prototyping Bragg grating on the three side of the polymer ridge waveguide using holographic interferometry and micro-molding processes. In this experiment, the master of the periodic structure was created on an i-line submicrometer positive photoresist film by a holographic interference using a He-Cd (325nm) laser. A subsequent mold using polydimethylsiloxane (PDMS) polymer was cast against this master and used as a stamp to transfer the grating pattern onto a UV cure epoxy. The technique shows accurate control for the transferring of a gratings period and depth. It can obtain the filtering result with very short grating length which means that it can be made with a small filtering device.

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MIZUNO, HIROTAKA, OKIHIRO SUGIHARA, TOSHIKUNI KAINO, YUKA OHE, NAOMICHI OKAMOTO, and MASAHITO HOSHINO. "THICK PHOTORESIST ORIGINAL MASTER: A NEW TOOL FOR FABRICATION OF POLYMERIC OPTICAL WAVEGUIDES WITH LARGE CORE BY HOT EMBOSSING." Journal of Nonlinear Optical Physics & Materials 13, no. 03n04 (December 2004): 513–17. http://dx.doi.org/10.1142/s0218863504002183.

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A simple and low-cost fabrication method of polymeric optical waveguides with large core sizes for plastic optical fibers is presented. The waveguides are fabricated by hot embossing with a rectangular ridge ultraviolet (UV)-cured epoxy resin stamper. The stamper is fabricated by replication of a rectangular groove mold that is made from silicone rubber replicated from a rectangular ridge original master made from thick photoresist (SU-8). A rectangular ridge shape of the original photoresist master of 1 mm size was realized by using a flattening process, which involves hot embossing before the exposure process and using a UV-cut filter during the exposure process.

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Ye, Huichun, Lianguan Shen, Mujun Li, and Likai Li. "A Microlens Array with Different Focal Lengths Fabricated by Roll-To-Roll UV Lithography." Polymers and Polymer Composites 26, no. 2 (February 2018): 155–59. http://dx.doi.org/10.1177/096739111802600203.

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A simple, highly efficient and low cost roll-to-roll (R2R) UV imprinting lithography facility was achieved for fabricating micro-structures. Firstly, a novel microlens array with focuses distributed on a curved surface was designed and analyzed by an optical software ZEMAX. Then an ultra-precision diamond machine was applied to generate the freeform microlens array features on the master mold, and a belt-type polydimethylsiloxane (PDMS) mold with a microlens array pattern was prepared from the machined master mold. The R2R process was employed to replicate the microlens arrays, followed by an evaluation of their profiles and optical properties. Our experiments demonstrate that the applied method is reliable and efficient for producing the polymeric microlens arrays.

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Umemoto, Sususmu, and Norimasa Okui. "Master curve of crystal growth rate and its corresponding state in polymeric materials." Polymer 43, no. 4 (February 2002): 1423–27. http://dx.doi.org/10.1016/s0032-3861(01)00707-8.

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Li, Hai-Fang, Jin-Ming Lin, Rong-Guo Su, Zong Wei Cai, and Katsumi Uchiyama. "A polymeric master replication technology for mass fabrication of poly(dimethylsiloxane) microfluidic devices." ELECTROPHORESIS 26, no. 9 (May 2005): 1825–33. http://dx.doi.org/10.1002/elps.200410357.

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Bianco, Andrea, Chiara Bertarelli, Giovanni Dassa, Giorgio Toso, and Giuseppe Zerbi. "Realization of Photochromic-Polymeric Films for Optical Applications." Advances in Science and Technology 55 (September 2008): 1–6. http://dx.doi.org/10.4028/www.scientific.net/ast.55.1.

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The peculiar property of reversible change of the refractive index (Δn) of photochromic systems, is suitably exploited to realize volume phase holographic gratings (VPHGs), which are finding applications in optics and in spectroscopic instrumentations. A large modulation of the refractive index between the two photochromic states and a relatively thick layer of good optical quality are the fundamental requirements for the materials to achieve a good diffraction efficiency. A backbone diarylethene polymer which combines good processing properties with a proper photochromic sensitivity is synthesised and studied. The large Δn between the two isomer states (i.e. Δn=0.03 measured at 1500 nm and the value is even higher at shorter wavelengths, approaching 0.1 near the visible) and the high transparency in the near infrared range make it a promising substrate for the realization of efficient VPHGs. First prototype of VPHGs based on photochromic diarylethene polymer films has been written by transferring the pattern of lines from a master and its functionality is shown.

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Chen, Xiao Hong, and Su Su Wang. "A Thermodynamic Approach to Long-Term Deformation and Damage for Polymeric Materials in Hygrothermal Environment." Key Engineering Materials 312 (June 2006): 21–26. http://dx.doi.org/10.4028/www.scientific.net/kem.312.21.

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In this paper, a thermodynamic approach is presented to model coupled fluid transport, heat transfer, long-term deformation and damage in polymeric materials. The well-known Gibbs free energy is expressed as a functional of stress, temperature and fluid concentration with damage being introduced as an internal state variable. Constitutive equations for nonlinear viscoelastic materials in hygrothermal environments are derived in memory functional forms. The kinetics of damage evolution induced by stress, temperature and fluid is described by a damage function with thermodynamic driving force. Governing equations for mass and heat transfer are obtained from transport laws relating fluid and heat fluxes to gradients of chemical potential difference and temperature. A superposition principle of time, temperature, fluid concentration, stress, and aging is proposed so that long-term property functions may be derived from momentary master curves by horizontal and vertical shifting. The approach provides a theoretical framework for evaluating longterm behavior of polymeric materials in hygrothermal environments from short-term experiments.

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Zhao, Rong Guo, Wen Bo Luo, Chu Hong Wang, and Xin Tang. "Effect of Stress-Induced Damage Evolution on Long-Term Creep Behavior of Nonlinear Viscoelastic Polymer." Key Engineering Materials 324-325 (November 2006): 731–34. http://dx.doi.org/10.4028/www.scientific.net/kem.324-325.731.

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The mechanical behaviors were investigated by nonlinear creep tests of poly(methyl methacrylate) under different temperatures. The test duration was 4000 seconds. The corresponding temperature shift factors, stress shift factors and temperature-stress shift factors were obtained according to time-temperature superposition principle, the time-stress superposition principle and the time-temperature-stress superposition principle (TTSSP). The master creep compliance curve up to about 1-month at a reference temperature 22 degrees centigrade and a reference stress 14 MPa was constructed, and the effect of stress-induced damage evolution on the long-term creep behavior of polymeric material was accounted. It was shown that TTSSP provides an effective accelerated test technique in the laboratory, the results obtained from a short-term creep test of poly(methyl methacrylate) specimen at high temperature and stress level can be used to construct the master creep compliance curve for prediction of the long-term mechanical properties at relatively lower temperature and stress level, and the master creep compliance curve with damage considered can be applied to accurately characterize the long-term creep behavior of nonlinear viscoelastic polymer.

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14

Ni, Ming. "Bioinspired systems: A new upcoming research master program at Yachay Tech University in Ecuador." Bionatura 4, no. 3 (August 15, 2019): 893–94. http://dx.doi.org/10.21931/rb/2019.04.03.1.

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Throughout history, people use different types of biomaterials to repair or replace damaged human tissues. Ancient Egyptians used golden wires to replace the missing teeth; Ancient Mayans used nacre or mother of pearl to achieve the same goal 1, 2. Fast forward to the 20th century; Sir Ridley used Perspex as the material for intraocular lenses 1. Many surgeons pioneered using synthetic polymeric membranes as the material for kidney dialyzers 1. The modern time of biomaterials has come. Science, instead of try-and-error, has been developed to study biomaterials systematically. Professor Larry Hench, who is the inventor of Bioglass©, came up a classification of three generations of biomaterials, starting from bioinert materials to bioactive materials, to the combining of bioactive materials and resorbable materials 3.

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Park, Kyoung Hoon, Jun Hong Park, and Dong Pyo Kim. "Fabrication of Nanoscale SiC-Based Ceramic Patterns with Near-Zero Residual Layers by Using Imprinting Technique and Reactive Ion Etching." Materials Science Forum 510-511 (March 2006): 766–69. http://dx.doi.org/10.4028/www.scientific.net/msf.510-511.766.

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Nano-scale SiC-based ceramic patterns on Si substrates were fabricated via imprint lithography technique by using viscous polyvinylsilane as a ceramic precursor and economic nano-scale master such as CD, followed by pyrolysis at 800oC under nitrogen atmosphere. The thickness of residual layers was controlled by varying the spin-coating conditions (solution concentration, spinning speed) and the patterning conditions (molding pressure). In addition, for the effective removal of the remaining residual layer, the etching kinetics of both polymeric and ceramic patterns was also comparatively studied by Ar or reactive ion etching process.

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Kim, Minsu, Eun Song Oh, and Moon Kyu Kwak. "Shrinkage-Considered Mold Design for Improvement of Micro/Nano-Structured Optical Element Performance." Micromachines 11, no. 10 (October 17, 2020): 941. http://dx.doi.org/10.3390/mi11100941.

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Polymer shrinkage in nano-imprint lithography (NIL) is one of the critical issues that must be considered in order to produce a quality product. Especially, this condition should be considered during the manufacture of optical elements, because micro/nano-structured optical elements should be controlled to fit the desired shape in order to achieve the intended optical performance. In this paper, during NIL, we characterized the shrinkage of polymeric resin on micro lens array (MLA), which is one of the representative micro/nano-structured optical elements. The curvature shape and optical performance of MLA were measured to check the shrinkage tendency during the process. The master mold of MLA was generated by the two-photon polymerization (2PP) additive manufacturing method, and the tested samples were replicated from the master mold with NIL. Several types of resin were adjusted to prepare the specimens, and the shrinkage effects in each case were compared. The shrinkage showed different trends based on the NIL materials and MLA shapes. These characterizations can be applied to compensate for the MLA design, and the desired performance of MLA products can be achieved with a corrected master mold.

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Yakovleva, Maria I. "MOSAICS IN THE REGIONAL MUSEUM OF MESSINA, THEIR STYLISTIC FEATURES AND PLACE IN THE ART OF THE EARLY PALAEOLOGAN PERIOD." RSUH/RGGU Bulletin. "Literary Theory. Linguistics. Cultural Studies" Series, no. 6 (2021): 65–77. http://dx.doi.org/10.28995/2686-7249-2021-6-65-77.

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The Regional Museum of Messina possesses four fragments of monumental mosaics originating from local churches. Their dating, as suggested in research literature, varies between the second half of the 13th century and the first third of the 14th. А question remains open concerning the roles that the authentic Byzantine and/or local Sicilian masters played in their creation. Messinian mosaic fragments show familiarity with methods of rendering faces which were not crystallized in Byzantine art before the origin of the mosaics in Kariye Camii (1316–1321). In the opinion expressed here, they were all produced during the first third of the 14th century, by local craftsmen who were guided by Constantinople models, although a manner they worked in was more simplified in comparison with metropolitan one. An exception is a mosaic depicting the archangel Michael, which could have been created by a visiting Byzantine master who had metropolitan training.

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Ahmad, Daniel, Nahiene Hamila, Khalid Lamnawar, and Philippe Boisse. "Mechanical Analysis and Simulation of the Thermoforming Process of Thin Polymer Sheets." Key Engineering Materials 504-506 (February 2012): 1111–16. http://dx.doi.org/10.4028/www.scientific.net/kem.504-506.1111.

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Most of industrial processes (thermoforming, injection moulding...) require the understanding of thermo-mechanical behaviour of polymeric sheets. Furthermore, the mastery of the deformation of the polymers becomes an important stake. In order to improve and complete the understanding of the deformation of thermoplastic polymer materials during their forming processes, the problem of modelling the thermoforming process for viscoelastic sheet under large strains is considered. The first step of the process that consists in heating the sheet using infrared lamps is taken into account by included a temperature field in viscoelastic behaviour laws under integral forms. The finite element simulation of the different steps will be presented

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AILENI, RALUCA MARIA, LAURA CHIRIAC, and RAZVAN ION RADULESCU. "A new perspective in e-learning training toolkit development for advanced textile research centres in Morocco and Jordan." Industria Textila 72, no. 05 (October 30, 2021): 569–78. http://dx.doi.org/10.35530/it.072.05.1849.

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This paper presents an overview of training/learning tools for advanced textile research centres in Morocco and Jordan. Within the Erasmus+ FOSTEX project, the main courses necessary for the training of researchers and students enrolled in master’s or doctoral programs in Morocco and Jordan and who will work within the advanced research centres have been identified and selected. Starting from good European practices on learning, teaching, research and testing services, several courses have been structured that offer knowledge on international conformity certification, standardization, quality management, testing/inspection, labelling, integration of technical specifications, testing physical-mechanical, colour resistance testing, tests specific to instrumental analysis and development of advanced materials. In order to improve the skills of human resources (research staff, masters and doctoral students), the Erasmus+ FOSTEX consortium has developed an extensive toolkit of learning-training, thematic workshops and services appropriate to the equipment purchased by partners in Morocco and Jordan for research centres in the field of advanced textiles.

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Masud, Md Matiul Hoque. "International Student Migration and Polymedia: The Use of Communication Media by Bangladeshi Students in Germany." Research in Social Sciences and Technology 5, no. 3 (November 1, 2020): 95–110. http://dx.doi.org/10.46303/ressat.05.03.5.

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Tertiary-level students from Bangladesh usually migrate to Germany for the purpose of higher studies. These international student migrants use communication media to maintain connections with family members and friends in Bangladesh and social networks with friends, classmates, and Bangladeshi community members in Germany. Drawing on the experiences of Bangladeshi student migrants in Germany and using polymedia theory, this paper investigates how the migrant students use the polymedia environment to maintain the transnational social networks and connections. This paper is based on qualitative data derived from 18 in-depth interviews with Bangladeshi migrant students in Germany. Findings suggest that using the polymedia environment, Bachelor migrant students receive emotional support from their family members back home, while Masters and PhD students are responsible for providing emotional and practical support to their left-behind families, relatives, and friends. Migrant students’ media usage with families and friends living in Bangladesh is influenced by their marital status and gender as well as their familial and social structure in Bangladesh. Their use of communication media with the members of the Bangladeshi community and foreign classmates living in Germany is comparatively less frequent and more education-oriented.

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Platé, N. A. "Reminiscences about the master." Polymer Science Series A 49, no. 12 (December 2007): 1244–46. http://dx.doi.org/10.1134/s0965545x07120024.

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Fiedler, Nicklas, Daniela Arbeiter, Stefan Oschatz, Niels Grabow, and Kerstin Lebahn. "Definition of test parameters for dynamic mechanical testing of polymeric implant materials." Current Directions in Biomedical Engineering 7, no. 2 (October 1, 2021): 684–87. http://dx.doi.org/10.1515/cdbme-2021-2174.

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Abstract The selection of appropriate test conditions is of critical importance in mechanical testing of biomaterials. In particular the definition of dynamic test conditions is requiring high efforts. In this work, a thermoplastic semicrystalline polymer was characterized regarding mechanical properties by dynamic mechanical analysis (DMA). Timetemperature- superposition (TTS) of dynamic mechanical data provides an efficient method for the experimental design of follow-up studies. Our focus was to provide test conditions for cyclic tests, which correspond to viscoelastic materials. The results show, that the test temperature for dynamic mechanical fatigue tests, as an indicator of mechanical modification for viscoelastic materials, should necessarily remain below the onset temperatures of storage modulus and loss modulus. Moreover, changes in material characteristics due to varying frequencies should be considered when constructing a master curve for the evaluation of test frequencies. Therefore, TTS is particularly beneficial for the rapid determination of test parameters for accelerated material examination.

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Oancea, Luminita, Corina Marilena Cristache, Alexandru Eugen Petre, Eugenia Panaitescu, Mihai Burlibasa, and Lucian Toma Ciocan. "Dimensional Accuracy of Digitalized Stone Models Obtained from Alginic Acid Polymer and Poly-dimethyl-siloxane Impressions." Materiale Plastice 57, no. 3 (September 30, 2020): 97–110. http://dx.doi.org/10.37358/mp.20.3.5384.

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The prognosis of the prosthetic rehabilitation is linked to the proper transfer of the clinical data to the dental laboratory, in the digital or conventional workflow. The aim of the present study was to compare the dimensional accuracy of analog and digitalized models, focusing on the influence of impression polymeric materials on the final digital model. Methods: The master model with standard reference points and the three groups of test models, obtained by alginic acid polymer impression (group A) and condensation-cured poly(dimethyl siloxane) in two impression techniques (1-step putty/light-body-group 1T, 2-steps putty/ light-body-group 2T), were measured in four standardized points before and after digitization. The differences from the master model and between the pair analog and digital models was calculated and statistically analysed using Mann-Whitney tests (2 groups), and one-way Anova (3 groups) with post-hoc Tukey s Test was applied for pairwise analysis (a;=0.05). Results: All analog and digitalized model tests showed altered dimensions from the master model. A general reduction of the digitalized models, in sagittal and transversal dimensions, was observed, comparing to the reference model. The impression material was a significant factor influencing dimensional accuracy. Conclusions: a statistically significant difference was found between most of the models and the master model. However, through digitalization, some of the errors were compensated. The digital models from alginic acid polymer group (group A) registered the highest trueness, with no statistically significant difference (P]0.05) from the reference model.

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Lim, Soon Hyuk, Nguyễn Hoàng Ly, Jung A. Lee, Ji Eun Kim, Se-Woong La, Vu Thi Huong, Thi-Giang Tran, et al. "Nanopatterned Polymer Molds Using Anodized Aluminum Templates for Anti-Reflective Coatings." Polymers 13, no. 19 (September 29, 2021): 3333. http://dx.doi.org/10.3390/polym13193333.

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This work introduces a facile geometry-controlled method for the fabrication of embossed and engraved polymeric moth-eye-inspired nanostructures in imprinting molds using anodic aluminum oxide (AAO) templates, resulting in a novel anti-reflective transparent coating. The moth-eye nanostructures are prepared directly on the surface of a flexible polyethylene terephthalate (PET) substrate. As a prerequisite procedure, a UV-curable polyurethane acrylate resin is spun on the PET. The shape of the moth-eye nanostructures can then be adjusted by controlling the size and shape of the nanopores in the AAO templates. Both embossed and concaved polymer moth-eye nanostructures were successfully mounted on a PET substrate. Embossed polymer replica molds were prepared using the AAO master templates in combination with an imprinting process. As revealed by field-emission electron microscope (FE-SEM) images, conical nanopatterns in the AAO template with a diameter of ~90 nm and a depth of ~100 nm, create a homogeneous embossed morphology in the polymer moth-eye nanostructure. The polymeric molds with the depths of 300 and 500 nm revealed the amalgamated structures in their apexes. In addition, a dip-imprinting process of the polymeric layers was implemented to yield a concaved mold by assembly on the surface of the 100 nm embossed polymer mold substrate. Considering that the embossed structures may be crumbled due to their protuberant shapes, the concaved geometries can have an advantage of stability in a certain application concerning physical degradation along with a higher transmission by ~2%, despite somewhat nonuniform structure. The experimental and theoretical results of this study indicate that this polymer layer has the potential for use in anti-reflective coating applications in transparent films.

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Sternstein, S. S., Samuel Amanuel, and Meisha L. Shofner. "Reinforcement Mechanisms in Nanofilled Polymer Melts and Elastomers." Rubber Chemistry and Technology 83, no. 2 (June 1, 2010): 181–98. http://dx.doi.org/10.5254/1.3548273.

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Abstract Mechanical reinforcement in nanofilled polymer melts and elastomers was investigated with emphasis on low filler concentrations ranging from zero to 12.5 vol. %. Composite samples were prepared using a poly(vinyl acetate) matrix with each of three different filler types. Two fumed-silica fillers with different surface chemistry were used. One had an untreated (not-treated) surface (NT) containing hydroxyl groups that can form hydrogen bonds with the matrix polymer, and one had a surface treatment (ST) that prevents such bonds from forming. In addition, a poly(tetrafluoroethylene) (PTFE) filler was used in order to provide no appreciable filler—matrix bonding. Dynamic mechanical data were obtained within the linear viscoelastic region using symmetric, simple shear specimens. Data are presented in the form of superposition master curves of storage shear modulus versus reduced frequency. The increase in storage modulus with filler addition is strongly dependent on the frequency of observation. At higher reduced frequencies, that is, the glassy end of the master curve, reinforcement R (defined as the storage modulus of the composite divided by that of the neat polymer, at a given reduced frequency) is low and has values typically predicted by micromechanics theory, ca. 1.5 at 12.5% filler. Conversely, at lower reduced frequencies in the rubbery plateau region, reinforcement is many times larger than what current theory predicts, ca. 50 or more. In addition, the long relaxation times of the matrix polymer are extended by filler addition, for example, by more than 2 decades for the 12.5% NT filler composite. The relaxation time distribution of the matrix polymer depends on the filler type and concentration, and the master curves themselves cannot be superposed. Of major importance, it is found that the reinforcement increases exponentially with a reduced filler volume fraction defined as the actual volume fraction ϕ divided by a scale factor ψ, that is, R=exp(ϕ/ψ). This scale factor, or “scaling volume fraction”, is specific to the filler-matrix composite system. The initial slope of the reinforcement versus filler volume fraction curve at zero filler is given by 1/ψ, which varies from 28.6 for NT filler to 3.57 for PTFE filler. These values should be compared to the 2.5 found in the Einstein and Guth-Gold theories, both of which fail to describe the physics of reinforcement in polymeric melts. The implications of these findings to the root mechanism of reinforcement and the origin of the Payne effect are discussed in terms of a postulated filler-induced conformational restriction model based on the physics of the polymeric matrix in the presence of filler.

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Ahmed, Ashraf Fathy, and Suong V. Hoa. "Thermal insulation by heat resistant polymers for solid rocket motor insulation." Journal of Composite Materials 46, no. 13 (October 11, 2011): 1549–59. http://dx.doi.org/10.1177/0021998311418850.

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A new method for the development (design, fabrication, and characterization) of asbestos-free rubbers for use as rocket motor insulators is presented. Such insulation is based on chopped carbon fiber (CCF) and aramid fiber in pulp form asreinforcement for ethylene propylene diene monomer (EPDM) along with ammonium polyphosphate (AP) flame retardant agent. Six millimeters long CCFs and/or Kevlar pulp (KP) are dispersed in the EPDM polymeric matrix to obtain a homogenous master batch for curing. The new method involves the development of two types of prepregs andthe lamination of these types of prepregs. The first one consists of CCF/EPDM/AP (50 phr CCF) and the second type of prepreg KP/EPDM/AP (30 phr KP). Laminates composed of six alternative layers of these prepregs have been shown to exhibit better thermal, mechanical, physical, and ablative properties than their non-laminated counterparts.

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Koesdjojo, Myra T., Corey R. Koch, and Vincent T. Remcho. "Technique for Microfabrication of Polymeric-Based Microchips from an SU-8 Master with Temperature-Assisted Vaporized Organic Solvent Bonding." Analytical Chemistry 81, no. 4 (February 15, 2009): 1652–59. http://dx.doi.org/10.1021/ac802450u.

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Kociubińska, Edyta. "Le dandy, maître de l’art de plaire en déplaisant." Romanica Silesiana 16, no. 2 (February 15, 2021): 115–23. http://dx.doi.org/10.31261/rs.2019.16.11.

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According to Jules Barbey d’Aurevilly, the obligation of every dandy is to become a true master in the art of pleasing by displeasing. His words, his tricks, his intrigues will give birth to the stereotype of the dandy conveyed by his contemporaries throughout the 19th century. By referring to the critical texts of the time and modern critical texts, we will attempt to review the main roles of a dandy: a master of elegance, idle master, misogynist master, impassive master, and finally, insolent master. The paper aims to prove that hidden behind the mask of the original eccentric is a rebel protecting his individuality against the surrounding mediocrity.

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Lambrigger, Markus. "Polymer crystallization kinetics, master quotients, master curves and Nakamura-Ozawa-equations of iPP and PTFE." Polymer Engineering and Science 44, no. 12 (2004): 2194–202. http://dx.doi.org/10.1002/pen.20247.

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Lambrigger, Markus. "Avrami Master Curves for Isothermal Polymer Crystallization." Polymer Journal 29, no. 2 (February 1997): 188–89. http://dx.doi.org/10.1295/polymj.29.188.

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Whitlow, Harry J., Li Ping Wang, and Leona Gilbert. "Transport of Water and Particles in Microfluidics Devices Lithographically Fabricated Using Proton Beam Writing (PBW)." Advanced Materials Research 74 (June 2009): 129–32. http://dx.doi.org/10.4028/www.scientific.net/amr.74.129.

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Proton beam writing (PBW) is a MeV ion beam lithography technique that has gained interest in many biological applications such as fabricating microfluidic devices for Lab-On-a-Chip (LOC) applications where capillary forces are important for fluid flow. PBW has a unique capability of being able to direct-write patterns in thick (1-30µm) polymer resist layers with straight vertical sidewalls. It can be used to prepare master stamps and moulds for mass production in polymeric materials. A recent development, where the direct writing of an entire pattern element is carried out in parallel makes PBW especially well suited for Bio-MEMS LOC applications. In this study we have examined the flow dynamics using video microscopy of deionised water in fluidic channel patterns fluid reservoirs, capillary sections and a capillary pump written by PBW. The video microscopy data also demonstrated that the wetting behavior of the surface strongly influences the dynamics of fluid flow. This makes new approaches for LOC fabrication feasible and powerful.

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Abitha, V. K., Ajay Vasudeo Rane, Rane Uday, Nikesh Samarth, Amit Vasudeo Rane, and Vinayak Kamble. "Studies in Effect of Nano Aluminium Trihydroxide Concentration on Flame Retardant Properties of Ethylene Propylene Diene Rubber." Advanced Engineering Forum 14 (October 2015): 3–18. http://dx.doi.org/10.4028/www.scientific.net/aef.14.3.

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The science and technology of synthetic polymers has undergone explosive growth in the last few decades and the number of different polymeric materials in our built environment increases almost daily. All organic polymers burn and thus entail some measure of fire hazard in some situations. With increasing awareness of the nation’s fire problem it has become evident that the problems associated with flammability of polymeric materials must be attacked and solved. With the large number of polymers in commercial use. Problems of flammability and fire retardation are complex and multifaceted properties have to be developed, or existing polymers must be modified by addition of fire-retardant compounds. EPDM Rubber has many attractive properties such as low shrinkage, ease of cure and processing, excellent moisture, solvent and chemical resistance, good mechanical and electrical properties, as well as ease of modification to optimize the properties. However flammability is a major limitation in area requiring high flame resistance. Aluminum trihydroxide (ATH) due to its flame retardancy property is widely used as non reinforcing filler in wires and cable compound along with silica and carbon black. In this study carbon black is fully replaced by nano ATH to make environment friendly rubber products. However, the dispersion of nano particles in rubber is remarkably poor and hence techniques like melt mixing, solution mixing and master batching of nano ATH with EVA (Ethylene- vinyl acetate) are used to improve the dispersion of nano ATH particles in EPDM elastomers. In the current study we have used melt mixing for improving the dispersion of nano ATH and excellent results were obtained with optimum loading of nano ATH.

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Jumarliansyah, Muhammad, Mila Hasanah, Ridha Darmawaty, and Faisal Mubarak. "ATSᾹR KAFᾹAH QIRᾹAT AL QUR’AN WA ITQᾹN AL MUFRADᾹT LADA AL THULLᾹB ‘ALA MAHᾹRAT AL QIRᾹAH." Al Mi'yar: Jurnal Ilmiah Pembelajaran Bahasa Arab dan Kebahasaaraban 4, no. 2 (October 9, 2021): 191. http://dx.doi.org/10.35931/am.v4i2.561.

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This study aims to examine the effect of reading Quran ability on reading skills, the effect of vocabulary mastery on reading skills, and the effect of reading Quran ability and vocabulary mastery on reading skills students at the Islamic senior high school Amuntai. This type of research is a survey, and the approach used in this research is quantitative. The population of this study was all students of Class XI majoring in MIA at the Islamic senior high school 1 HSU, the Islamic senior high school 2 HSU, and the Islamic senior high school NIPA RAKHA Amuntai, totaling 240 people, and with the sampling technique 25% of the existing population as many as 60 people. The data collection instrument is documentation. The data analysis technique uses multiple regression analysis. The results of this study showed that the reading Quran ability students were in the medium a value of 53%, the vocabulary mastery students were in the medium a value of 72%, and the reading skills students were in the medium a value of 67%. While the effect of reading Quran ability on reading skills was 66.3% which means that there was an effect between the reading Quran ability on reading skills students. While vocabulary mastery on reading skills was 79.4%, there was an effect. Moreover, the effect of reading Quran ability and vocabulary mastery on reading skills students was 85.9%, which means that there is an effect between the reading Quran ability and vocabulary mastery on reading skills students.Keyword: Reading Quran, Vocabulary Mastery, Reading Skills.

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Chan, T. V., G. D. Shyu, and A. I. Isayev. "Master curve approach to polymer crystallization kinetics." Polymer Engineering and Science 35, no. 9 (May 1995): 733–40. http://dx.doi.org/10.1002/pen.760350902.

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Zhao, Rong Guo, Wen Bo Luo, Qi Fu Li, and Chao Zhong Chen. "Application of Time-Ageing Time and Time-Temperature-Stress Equivalence to Nonlinear Creep of Polymeric Materials." Materials Science Forum 575-578 (April 2008): 1151–56. http://dx.doi.org/10.4028/www.scientific.net/msf.575-578.1151.

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Based on the observations that high temperature accelerates creep rate of polymer while physical ageing plays a reverse role, and that there is an analogy between the influences of stress and temperature on the intrinsic times of polymers, the time-ageing time superposition principle (TASP) and the time-temperature-stress superposition principle (TTSSP) are used to evaluate the long-term creep behavior of poly(methyl methacrylate) (PMMA). PMMA specimens were aged for 2 to 120 hours at identical temperature, their short-term creep strains with 2-hour test duration were measured under various stress levels ranging from 14 to 30 MPa at room temperature, and modeled by means of time-ageing time equivalence and time-stress equivalence. The results show that the creep rate increases with stress, but decreases with ageing time. The ageing time shift factors vary with the stresses at which the shifts are applied. The ageing shift rate is independent on imposed stress in linear viscoelastic region, while it decreases with increasing stress when the material behaves in a nonlinear viscoelastic manner. The master creep compliance curve up to about 1-month at reference ageing time 120 hours and stress 18 MPa, which is nearly 2.5 decades longer than the test duration, is constructed by shifting the creep curves horizontally along the logarithmic time axis. The result illustrates that TTSSP, combined with TASP, provides an effective accelerated test technique for long-term mechanical behaviors of polymers.

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Ivanova, O. B., S. V. Shukhaev, and A. D. Loginоva. "Comparison of keratometric data of a standard automated keratometer and a Scheimpflug camera in patients with uncomplicated cataracts." Modern technologies in ophtalmology, no. 5 (October 20, 2021): 169–73. http://dx.doi.org/10.25276/2312-4911-2021-5-169-173.

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Purpose. To compare keratometry data based on principles of Gaussian optics and ray tracing method. Material and methods. The study involved 60 patients (60 eyes). Comparative assessment of three groups of keratometric data obtained from optical biometer IOL Master 500 and Axial/Sagital and Total Corneal Refractive Power maps from Pentacam-HR was carried out. Results. When analyzing the obtained indicators, reliably significant results were revealed only when comparing the data of Total Corneal Refractive Power, based on the ray tracing, with classical keratometry IOL Master 500. A comparative assessment of the obtained keratometric data of two Pentacam-HR maps did not show a statistically significant difference, as well as the indicators of classical keratometry Pentacam-HR and IOL Master 500. Conclusion. 1. Evaluation of keratometry data in patients with uncomplicated cataract based on Gaussian optics showed comparable values for the Pentacam-HR and IOL Master 500. There was no significant difference in keratometric values in the comparative analysis of data from Pentacam-HR between classical keratometry and Total Corneal Refractive Power. 2. Total Cornea Refractive Power from Pentacam HR based on ray tracing determined significantly lower values in comparison with the classic keratometry IOL Master 500. Key words: keratometry, corneal refractive power, ray tracing, keratotomography.

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Wu, D., D. Gu, J. Huo, D. Pu, and W. Wen. "Atactic Polypropylene-Filler Master Batch Technique." International Polymer Processing 2, no. 3-4 (March 1988): 155–61. http://dx.doi.org/10.3139/217.880155.

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Higuchi, Yoichi. "Development and Evaluation of the Binary Hologram Master." Journal of Photopolymer Science and Technology 2, no. 2 (2007): 271–75. http://dx.doi.org/10.2494/photopolymer.2.271.

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Higuchi, Yoichi. "Development and Evaluation of the Binary Hologram Master." Journal of Photopolymer Science and Technology 20, no. 2 (2007): 271–75. http://dx.doi.org/10.2494/photopolymer.20.271.

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Rajic, Aleksandar, Eleonora Desnica, Ivan Palinkas, Dorian Nedelcu, and Ljubica Lazic Vulicevic. "3D Printing Technology with Plastic Materials for Hip Implant Master Patterns Manufacturing." Materiale Plastice 56, no. 4 (December 30, 2019): 882–90. http://dx.doi.org/10.37358/mp.19.4.5280.

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This paper describes a hip implant model designed to assess the Fused Deposition Modeling (FDM) process for manufacturing investment casting master patterns. In addition, an indirect approach toward manufacturing master pattern via silicone rubber moulding in conjunction with 3D Printing process manufactured hip implant master pattern has been investigated. The dimensional accuracies of the manufactured AM master patterns and the wax pattern are presented. Finally, cost and lead time comparisons carried out between FDM ABS pattern manufacturing, indirect pattern manufacturing via silicone rubber moulding and conventional pattern manufacturing by metal mould are also presented.

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Behrens, Bernd Arno, Richard Krimm, Jan Jocker, Eduard Reithmeier, Bernhard Roth, and Maik Rahlves. "Method to Emboss Holograms into the Surface of Sheet Metals." Key Engineering Materials 549 (April 2013): 125–32. http://dx.doi.org/10.4028/www.scientific.net/kem.549.125.

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Holograms are industrially used as decorative design elements to increase the value of products. As they are hard to copy, holograms are also used for brand protection and product identification. The state-of-the-art is to emboss holograms in the surface of polymeric foils and to apply them to products by adhesive bonding. Examples are holograms on credit cards, banknotes or identification cards. In this paper, a new method to emboss holograms in the surface of sheet metals is presented. By this, parts made of sheet metal such as decorative interior parts of cars, battery housings or packaging of cosmetic products can be equipped with holograms during their production process. Hence, adhesive bonding and the required additional handling operations are not necessary. An embossing tool and the results of experimental hologram embossing are described. Aluminium Al99.9, aluminium-magnesium alloy AW-5505, copper and zinc-coated deep drawing steel DC05 were used as sheet metals to be embossed. Furthermore, a new method and a device to produce master holograms are presented. Master holograms are required to produce embossing dies with the hologram on its surface (referred to as shim). The device is based on a laser light source and a spatial light modulator (SLM). With help of the SLM, simultaneous transfer of 1920 x 1080 pixels of a Computer Generated Holograms (CGH) topography to a plate coated with photoresist is possible. Compared to todays industrial mastering of holograms which is done pixel by pixel, the time required for the process is much shorter. In addition, investment costs are lower compared to currently used electron-beam-lithography devices.

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Makarian, Jennifer. "German compounding and master batch industry remains strong." Plastics, Additives and Compounding 10, no. 2 (March 2008): 26–28. http://dx.doi.org/10.1016/s1464-391x(08)70057-6.

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Guerra, Marcos Antônio, Neide Aparecida Mariano, Alfeu Saraiva Ramos, and Maria Gabriela Nogueira Campos. "Processing of Pet-Silver Nanocomposite Filaments." Materials Science Forum 869 (August 2016): 350–55. http://dx.doi.org/10.4028/www.scientific.net/msf.869.350.

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Nanoparticles play a fundamental role on nanocomposite properties, as they significantly increase the contact area and allow a homogeneous distribution in comparison to microparticles. Silver nanoparticles (AgNP) have been extensively used in biomedical and engineering applications due to their interesting properties, such as antibacterial activity. Polyethylene terephthalate (PET) is a semi-crystalline polymer and has excellent chemical resistance and thermal stability. Because of its remarkable properties, PET has been used in several industrial applications, such as packaging, electrical, automotive, construction and textile. The aim of this study was to prepare potential antimicrobial PET-AgNP nanocomposite filaments for textile applications. Therefore, AgNP were incorporated in the PET matrix at different concentrations (0.05; 0.10; 0.15; 0.20; 0.25; 0.30; 0.35 and 0.40%) by extruding the PET resin with specific amounts of a 10% (w/w) AgNP/PET master batch. Then, rheological characterization was carried out and filaments were produced for mechanical, optical and thermal analyses. The incorporation of up to 0.20% (w/w) of AgNP in the polymeric matrix has not significantly altered overall properties of PET nanocomposites. Moreover, the nanocomposite incorporated with 0.05% of AgNP demonstrated suitable intrinsic viscosity for fiber processing and PET-like mechanical, thermal and optical properties.

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Zhou, Shihao, Xuansheng Fang, Yaolong He, and Hongjiu Hu. "Towards a Deeper Understanding of Creep and Physical Aging Behavior of the Emulsion Polymer Isocyanate." Polymers 12, no. 6 (June 26, 2020): 1425. http://dx.doi.org/10.3390/polym12061425.

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Information of the relaxation behaviors of polymer film is crucial to judge the durability of emulsion polymer isocyanate (EPI) as a structural adhesive for bonding timber-based products. A sequence of tensile creep tests and free volume evaluation of the cured EPI adhesive films during isothermal condition were carried out by dynamic mechanical analysis and positron annihilation lifetime spectroscopy, respectively. It is the first time to explore the creep response and physical aging of the EPI film, as well as associated microstructural evolution. The results indicate that the creep characteristics of the glassy EPI coating intimately depend upon the crosslinker and elapsed time, and the ideal momentary creep master curve can be constructed in terms of modified horizontal shifting method. Furthermore, the relaxation process is found to be dominated by vacancy diffusion mechanism. In addition, increasing the polymeric isocyanate content can significantly enhance the resistance to creep deformation of EPI films, but also accelerate the physical aging process. Due to a higher packing degree of pure polymer films, the EPI films with aqueous emulsified isocyanate exhibit much better relaxation resistance compared to that with general isocyanate crosslinker.

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45

Lambrigger, Markus. "Non-isothermal polymer crystallization kinetics and Avrami master curves." Polymer Engineering & Science 38, no. 4 (April 1998): 610–15. http://dx.doi.org/10.1002/pen.10225.

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Steller, Ryszard, and Jacek Iwko. "Shear Stress‐Dependent Viscosity Master Curves for Practical Applications." Polymer Engineering & Science 60, no. 1 (October 18, 2019): 44–54. http://dx.doi.org/10.1002/pen.25257.

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47

Wunde, Matthias, and Manfred Klüppel. "VISCOELASTIC RESPONSE DURING CRACK PROPAGATION OF UNFILLED AND FILLED SBR." Rubber Chemistry and Technology 91, no. 4 (October 1, 2018): 668–82. http://dx.doi.org/10.5254/rct.18.81537.

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ABSTRACT The crack propagation behavior of unfilled and filled styrene–butadiene rubber (SBR) in steady and dynamic tearing was investigated using tensile tests on trousers samples and tear fatigue measurements on single edge notched tension (SENT) samples, respectively. For the unfilled sample, both types of measurements indicated that the tearing energy is dominated by the viscoelastic response of the polymer. This was demonstrated by the creation of crack growth master curves using the horizontal shift factors obtained from mastering the complex modulus. The tearing energy increased with increasing crack velocity and decreasing temperature as required by the time-temperature superposition principle. The crack growth master curves followed a power law with the same exponent for steady and dynamic tearing. This exponent agrees fairly well with the exponent predicted by linear viscoelastic crack propagation theory. For steady tearing at high crack propagation rates, systematic deviations from the master curves appeared, which were attributed to flash temperature effects. For the filled SBR, which contained 50 phr carbon black, only dynamic tearing was found to be dominated by the viscoelastic response of the polymer. For steady tearing, filler networking seemed to alter crack propagation rates significantly, so that the viscoelastic fingerprint was no longer visible. For the filled sample, additional measurements with a high preload were conducted. It was demonstrated that a single master curve can be constructed, only if the (static) preload contribution is neglected and the dynamic contribution of the energy density is used for the evaluation of the tearing energy. This master curve showed two distinct slopes at high and low crack velocities. It is argued that the higher slope at low crack speeds is relevant for lifetime predictions based on the integration of the Paris–Erdogan power law. Under conditions in which the viscoelastic crack propagation holds, very slow crack growth rates can be explored at reasonable testing times by measurements at elevated temperatures.

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Stacer, R. G., E. D. von Meerwall, and F. N. Kelley. "Time-Dependent Tearing of Carbon Black-Filled and Strain Crystallizing Vulcanizates." Rubber Chemistry and Technology 58, no. 5 (November 1, 1985): 913–23. http://dx.doi.org/10.5254/1.3536103.

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Abstract 1. Unstable tearing can be minimized and tear-tip diameter held reasonably constant for carbon black-filled and strain-crystallizing vulcanizates using a constrained trouser tear testpiece first suggested by Gent and Henry. In the absence of these complicating features, the tear energy has been shown to be thermo-rheologically simple, readily lending itself to time-temperature superposition over a broad range of temperatures and rates. 2. Shift factors used to superpose tear energy data at different temperatures for both filled and unfilled SBR also superposed small deformation stress-relaxation data. This result did not hold for the NR formulations tested, indicating that the temperature dependency of the principal viscoelastic process is different for these properties. Evidence of this was observed in the thermal expansion coefficient, a, derived from the WLF coefficients, which increased by a factor of 10 for tear energy data. It is concluded that even with the tear path constrained, strain-induced crystallization still occurs near the tear tip for the NR formulations. 3. Temperature-reduced tear energy master curves for both filled and unfilled vulcanizates showed the same general tear behavior when referenced to Tg. At high rates or low temperatures, the master curves coincide, approaching a characteristic tear energy of approximately 50 kJ/m2, regardless of formulation. Only at lower rates did the different nature of the rubbers become apparent. All the master curves showed evidence of a tear energy plateau between −15 and −10 decades in rate, with the NR compounds showing the lowest slopes in this region. 4. Addition of filler increases the tear energy by approximately 20–40% over most of the master curves. This supports a previous conclusion of Gent and Henry that the major effect of reinforcing filler is to dissipate energy over a larger volume of material without significantly increasing inherent strength. Addition of filler also tended to mask the plateau in the tear energy master curve and decrease both the free volume at Tg and the thermal expansion coefficient of the material.

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Lajewski, Silvia, Annika Mauch, Kalman Geiger, and Christian Bonten. "Rheological Characterization and Modeling of Thermally Unstable Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV)." Polymers 13, no. 14 (July 13, 2021): 2294. http://dx.doi.org/10.3390/polym13142294.

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Presently, almost every industry uses conventional plastics. Its production from petroleum and extensive plastic pollution cause environmental problems. More sustainable alternatives to plastics include bioplastics such as poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), which is produced by bacteria and is biodegradable even in seawater. High temperature sensitivity as well as massive thermal degradation cause difficulties during the processing of PHBV. The aim of this work is to create a detailed rheological characterization and master curves to gain deeper knowledge about the material and its processing parameters. The rheological characterization was performed with frequency sweeps in the range of 0.1 rad/s to 628 rad/s and time sweeps over 300 s. Creating master curves at the reference temperature of 180 °C with the software IRIS delivers Carreau and Arrhenius parameters. These parameters allow for a calculation of the master curves for all other temperatures by means of the temperature shift factor. Moreover, the rheological measurements reveal a minimum rheological measurement temperature of 178 °C and a surprisingly high activation energy of 241.8 kJ/mol.

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HENECZKOWSKI, MACIEJ, and GRZEGORZ JABLONSKI. "The I-DEAS Master Seriessystem - its structure and applications." Polimery 41, no. 07/08 (July 1996): 463–68. http://dx.doi.org/10.14314/polimery.1996.463.

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Journal articles on the topic 'Polymeric masters'

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