Papers by Keyword: Polymer

Paper TitlePage

Authors: B. Notario, Javier Pinto, E. Solórzano, J. Escudero, J. Martín de León, D. Velasco, Miguel A. Rodríguez-Pérez
Abstract: An own-designed pressure vessel with glass windows has been employed to perform an in-situ characterization of the temporal evolution of the crystallization process of an amorphous polylactic acid (PLA) under different controlled CO2 pressures and temperatures. It has been proven that crystallinity can be related to optical parameters such as transmissivity, obtaining information about the whole process by optical measurements. The method has the advantage of measuring in-situ over bulk samples with a non-destructive tool. The obtained results have shown some unexpected trends that have been explained taking into account the complex phenomena occurring during the crystallization process of PLA in the presence of CO2 at high pressure.
Authors: Tie Jun Wang, Wen Xu Zhang, Kikuo Kishimoto, Mitsuo Notomi
Abstract: Body-centered cubic unit cell models and three-dimensional finite element method are used to study the inelastic deformation of rubber particle modified polymers. Calculations are carried out for three loading conditions, i.e. uniaxial loading, plane strain deformation loading and the so-called 'equivalent shear' loading. Distributions of the localized shear deformation are presented to understand the microscopic deformation mechanisms of the polymers. Effects of particle size, particle volume fraction and loading conditions on the micro- and macroscopic deformation behavior of rubber particle modified polymers are discussed.
Authors: Masaru Aniya, Masahiro Ikeda, Sahara
Abstract: In order to investigate the relationship between the bonding nature and the cooperative relaxation, a comparative study of the relaxation behavior in polymeric and metallic glass forming systems has been performed based on the Bond Strength–Coordination Number Fluctuation (BSCNF) model developed by the authors. In the present work, we studied the correlations between the fragility m, the Vogel temperature T0, the degree of molecular cooperativity NB, and the Kohlrausch exponent βKWW. The results show that T0 and NB increase, whereas βKWW decreases systematically with the increase of m. Reflecting the difference of the interatomic interactions of the materials considered, the analysis by the present study reveals that the value of NB in ion-conducing polymers is about 5 times larger than that in metallic systems, and for each system, the material dependence of βKWW is clearly seen in the fragility index m and the cooperativity NB.
Authors: G. Jamieson, C. Gerets, F.C. Duval, N.P. Pham, F. Iker, T. Funaya, Werner Boullart
Abstract: In this paper we review the effects of the plasma descum steps used in current process flows for the fabrication of Cu interconnects embedded in polymer, paying particular attention to polymer residues that are not easily removed in a gentle oxygen only plasma.
Authors: Peng Li, Li Zhi Gu
Abstract: By analyzing factors affecting the accuracy of boring process on the precision boring machine, the article aims at putting forward a method of improving the accuracy of boring process by means of installing polymer elastic shock absorbers on unilateral boring tools. In addition, the situation of non-linear radial forced vibration is formulated by a dynamic model of second-order differential equation. Based on the model, vibration prevention principles of unilateral boring tools have been discussed and systematic parameters have been optimized for enhancement of the boring process accuracy.
Authors: Leonid Rodionov, Pavel Rekadze, Jarosław Stryczek
Abstract: Progress in the field of microelectronics and micromechanics has created new opportunities for the development of fluid power microsystems and microhydraulics. Miniaturization of hydraulic elements allows replacing the classical hydraulics with microhydraulics, where due to size or weight the former cannot be applied. Gear pumps are common use due to their reliability, resistance to working medium impurities, high efficiency, small size in comparison with other pumps and simple and compact design. Therefore micropumps often associate with a gear pump type. A micropump entails microbearings production. This requirement leads to cost increasing due to requirements to high accuracy of manufacturing. The paper focuses on a method for micropumps production without bearings. The idea based on application of materials with satisfactory friction coefficient in pairs. Friction pairs analysis made from different polymer and composite materials was carried out. As a result a gear micropump was designed and produced.
Authors: Guo Feng Wang, Lian Zhen Song, Zhi Li Wei, Xue Wu Wang
Abstract: Based on the viscosity of 10mPa.s after high speed shearing and the limit surfactants up to ultra-low interfacial tension, polymers and surfactant systems suitable for Longhupao oilfield were optimized by means of mixing formation simulation water with different polymers and surfactants. The relationship between the interfacial tension of the compound system and the component concentration, the effect of surfactants on viscosity, the injectivity of the compound system, etc. were studied on the basis of the research on the binary compound system. The results indicate that the viscosity of the compound system is lower than that of a single polymer solution to a certain degree and the compound system has good migration character in cores. In addition, core flooding experiments on slug combination optimization were made. The experiment results show that the compounded system with pre-pad polymers and surfactants has good oil displacement efficiency and in terms of enhancing the recovery efficiency, chemical flooding should be implemented as soon as possible.
Authors: Xiao Hu Zheng, Chang Yong Han
Abstract: This paper investigated an novel wireless RF pressure sensor fabricated with SU-8 polymer. The sensor consists of an inductor (L) interconnected with pressure-variable capacitor (C) to form a LC resonant circuit. The fabricated devices is 4 × 3 mm2 in size and houses 9 turns of Cu electro-plated coil with inductance of 100 nH. In this system, RF signal was transmitted from external antenna to the fabricated LC resonator. Then RF signal was changed as power of fabricated device via inductive coupling. The external antenna was modulated by resonant frequency of the LC resonator. By detecting this abrupt resonant frequency shift of the device, the pressure change of the device can be measured by wireless method.
Authors: Xiao Wei Liu, Xiao Wei Han, He Zhang, Xi Yun Jiang, Lin Zhao
Abstract: A new bonding technique mainly for PMMA microfluidic chips is presented in this paper. In this technique, polymer microfluidic microchannels were bonded by microwave radiation. Its strength and time can be controlled accurately in watt and second level. There are so many techniques for mass-production of polymer microfluidic chip, such as heat bonding, ultrasonic bonding. However, we may find different kinds of shortages when we use these techniques. In this paper, the experiment result shows that microwave radiation’s strength and time have effects on microfluidic chip`s bonding strength. The microwave absorbing coating can also have a certain degree influence on microfluidic chip`s bonding strength.
Authors: Tie Jun Wang, Kikuo Kishimoto, Mitsuo Notomi
Showing 1 to 10 of 571 Paper Titles