نتایج جستجو برای: polymer network

تعداد نتایج: 761421  

Journal: :Physical review. E, Statistical, nonlinear, and soft matter physics 2001
A Jákli G G Nair C K Lee R Sun L C Chien

The transfer of chirality from nonchiral polymer networks to the racemic B2 phase of nonchiral banana-shaped molecules is demonstrated. This corresponds to the transfer of chirality from an achiral material to another achiral material. There are two levels of chirality transfers. (a) On a microscopic level the presence of a polymer network (chiral or nonchiral) favors a chiral state over a ther...

2014
C. Okafor M. Maaza T. Mokrani

A proton exchange membrane has been developed for direct methanol fuel cell (DMFC). The nanofiber network composite membranes were prepared by interconnected network of Nafion (perfuorosulfonic acid) nanofibers that have been embedded in an uncharged and inert polymer matrix, by electro-spinning. The spinning solution of Nafion with a low concentration (1 wt% compared to Nafion) of high molecul...

1999
Hong Liu Aniket Bhattacharya Amitabha Chakrabarti

Results from molecular dynamics simulations of phase separation in a quenched polymer solution are presented for both twoand three-dimensional systems. Simulations clearly demonstrate the existence of a networklike pattern formation at an early to intermediate time regime for sufficiently dense polymer solutions. This network structure, however, relaxes at late times as the minimization of the ...

2017
Akira Onuki Ryoichi Yamamoto Takashi Taniguchi

We numerically investigate nonlinear regimes of shear-induced phase separation in entangled polymer solutions. Use is made of a time-dependent Ginzburg-Landau model describing two fluid dynamics of polymer and solvent. As a new dynamic variable a conformation tensor is introduced to represent chain deformations. Above the coexistence curve a dynamical steady states is attained, where fluctuatio...

Journal: :Soft matter 2014
Jianxiang Shen Jun Liu Yangyang Gao Xiaolin Li Liqun Zhang

By setting up a coarse-grained model of polymer nanocomposites, we monitored the change in the elastic modulus as a function of the strain, derived from the stress-strain behavior by determining uniaxial tension and simple shear of two typical spatial distribution states (aggregation and dispersion) of nanoparticles (NPs). In both these cases, we observed that the elastic modulus decreases non-...

2017
Ting Liang Huub P C van Kuringen Dirk J Mulder Shuai Tan Yong Wu Zandrie Borneman Kitty Nijmeijer Albertus P H J Schenning

In this work, the decisive role of rigidity, orientation, and order in the smectic liquid crystalline network on the anisotropic proton and adsorbent properties is reported. The rigidity in the hydrogen-bonded polymer network has been altered by changing the cross-link density, the order by using different mesophases (smectic, nematic, and isotropic phases), whereas the orientation of the mesog...

In this paper, the focus is on a new kind of biodegradable semi-interpenetrating polymer networks, which derived from ɛ-caprolactone, lactide, 1,4-butane diisocyanate and ethylenediamine and also its potential has been investigated in soft tissue engineering applications. The polymers were characterized by nuclear magnetic resonance (NMR) spectrometry, fourier transform infrared spectroscopy (F...

پایان نامه :دانشگاه آزاد اسلامی - دانشگاه آزاد اسلامی واحد تهران مرکزی - دانشکده علوم پایه 1390

abstract in this study, we synthesized a novel template polymer by using methacrylic acid (mma) as functional monomer, ethylene glycol dimethacrylate(egdma) as cross linker, 2,2-azobisisobutyronitrile (aibn) as initiator and olanzapine as targeted molecule in the presence of chloroform and acetonitrile as solvent. the products have been characterized and confirmed by (chn)elemental analysis,...

2017
Ritu Goyal Murat Guvendiren Onyi Freeman Yong Mao Joachim Kohn

The design of composite tissue scaffolds containing an extracellular matrix (ECM) and synthetic polymer fibers is a new approach to create bioactive scaffolds that can enhance cell function. Currently, studies investigating the effects of ECM-deposition and decellularization on polymer degradation are still lacking, as are data on optimizing the stability of the ECM-containing composite scaffol...

2013
Andrea Camposeo Israel Greenfeld Francesco Tantussi Stefano Pagliara Maria Moffa Francesco Fuso Maria Allegrini Eyal Zussman Dario Pisignano

The properties of polymeric nanofibers can be tailored and enhanced by properly managing the structure of the polymer molecules at the nanoscale. Although electrospun polymer fibers are increasingly exploited in many technological applications, their internal nanostructure, determining their improved physical properties, is still poorly investigated and understood. Here, we unravel the internal...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید