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Li Q.,Key Laboratory of Beijing City on Preparation and Processing of Novel Polymer Materials | Zhao S.,Key Laboratory of Beijing City on Preparation and Processing of Novel Polymer Materials | Zhao S.,Beijing University of Chemical Technology | Pan Y.,Key Laboratory of Beijing City on Preparation and Processing of Novel Polymer Materials
Journal of Applied Polymer Science | Year: 2010

The vulcanization properties, mechanical properties of hydrogenated nitrile rubber (HNBR) filled with carbon black (N550), zinc dimethacrylate (ZDMA), SiO2 independently and two of three kinds of fillers together were investigated, respectively. The filler-dispersion was characterized by the transmission electron microscopy (TEM) and dynamic mechanical properties. The results showed that HNBR composite filled with SiO2 or ZDMA displayed high tensile strength, elongation at break and compression set. The HNBR composite filled with N550 displayed low compression set, tensile strength and elongation at break. The dispersion of SiO2 in HNBR compound was better than that in HNBR vulcanizates because of SiO2 particles self-aggregation in vulcanizing processing. ZDMA particles with micron rod-like and silky shape in HNBR compounds changed into near-spherical poly-ZDMA particles with nano size in HNBR vulcanizates by in situ polymerization reaction. The N550 particles morphology exhibited no much change between HNBR compounds and vulcanizates. N550/ZDMA have the most effective reinforcement to HNBR and the appropriate amount of ZDMA is about 25% of total filler amount by weights. The theory prediction for Payne effect (dispersion of the filler) shown by the dynamic properties is identical with actual state observed by TEM. © 2010 Wiley Periodicals, Inc. Source


Fu Y.,State Key Laboratory of Organic Inorganic Composites | Fu Y.,Beijing University of Chemical Technology | Liu L.,Key Laboratory of Beijing City on Preparation and Processing of Novel Polymer Materials | Liu L.,Beijing University of Chemical Technology | And 4 more authors.
ACS Applied Materials and Interfaces | Year: 2014

Using tetraethyl orthosilicate as a main raw material, silica nanofibers (SiNFs) were prepared through the combination of a sol-gel process and an electrospinning technique followed by pyrolysis. Surface modified electrospun SiNFs developed by self-polymerization of polydopamine on the surface (SiNFs-PDA) served as templates for the electroless plating of silver nanoparticles (Ag NPs), using glucose as a reducing agent. The electrical resistivity of silver coated SiNPs-PDA (SiNFs-PDA/Ag) was measured by the four-point probe method and was found to be as low as 0.02 mΩ·cm at room temperature. The morphology of SiNFs-PDA/Ag before and after the blending with silicon rubber indicated a strong interaction between the silver layer and the SiNFs-PDA. The electrical and mechanical properties of the silicon rubber filled with SiNFs-PDA/Ag were studied to demonstrate the conductive performance application of SiNFs-PDA/Ag. © 2014 American Chemical Society. Source


Wang L.,Key Laboratory of Beijing City on Preparation and Processing of Novel Polymer Materials | Zhao S.,Key Laboratory of Beijing City on Preparation and Processing of Novel Polymer Materials | Zhao S.,Beijing University of Chemical Technology | Li A.,Key Laboratory of Beijing City on Preparation and Processing of Novel Polymer Materials | And 2 more authors.
Polymer | Year: 2010

Solution polymerized styrene-butadiene rubber (SSBR) and SSBR with tert-Butylchlorodiphenylsilane (TBCSi, large-volume functional groups) at the two ends of macromolecular chains (T-SSBR) were prepared by anionic polymerization. The molecular structure parameters of T-SSBR and SSBR were characterized and the ratio of the amount of macromolecular chain ends connected with TBCSi to total macromolecular chain ends (i.e., end-capping efficiency) was calculated. The comprehensive properties of T-SSBR and SSBR composites filled with carbon black (CB) were investigated. The results showed that T-SSBR composites presented lower Payne effect (namely better CB dispersion) than those of SSBR composites, which led to decrease in hardness, internal friction, dynamic compression heat built-up and permanent set of T-SSBR composites, significant increase in tensile strength, elongation at break, tear strength and resilience of T-SSBR composites, and excellent balance between wet-skid resistance and rolling resistance. However, compared with SSBR composites, T-SSBR composites presented longer stress-relaxation time, bigger die-swell and higher apparent viscosity, as well as slightly inferior dynamic-cutting resistance. All the above, owing to the end-capping of TBCSi, which could immobilize the free chain ends of T-SSBR (i.e., to reduce the friction loss of molecular chains and create a greater degree of orientation in the force field), and adsorb CB, the comprehensive performances of T-SSBR were better than those of SSBR and T-SSBR terminated with styrene-TBCSi (TS-SSBR) were far superior to those of T-SSBR terminated with butadiene-TBCSi (TB-SSBR). Accordingly, the former was suitable for the tread of green tires. © 2010. Source


Liu J.,Key Laboratory of Beijing City on Preparation and Processing of Novel Polymer Materials | Liu J.,Beijing University of Chemical Technology | Wu Y.,Key Laboratory of Beijing City on Preparation and Processing of Novel Polymer Materials | Shen J.,Key Laboratory of Beijing City on Preparation and Processing of Novel Polymer Materials | And 3 more authors.
Physical Chemistry Chemical Physics | Year: 2011

By tuning the polymer-filler interaction, filler size and filler loading, we use a coarse-grained model-based molecular dynamics simulation to study the polymer-filler interfacial structural (the orientations at the bond, segment and chain length scales, chain size and conformation), dynamic and stress-strain properties. Simulated results indicate that the interfacial region is composed of partial segments of different polymer chains, which is consistent with the experimental results presented by Chen et al. (Macromolecules, 2010, 43, 1076). Moreover, it is found that the interfacial region is within one single chain size (Rg) range, irrespective of the polymer-filler interaction and the filler size, beyond which the bulk behavior appears. In the interfacial region, the orientation and dynamic behaviors are induced by the interfacial enthalpy, while the size and conformation of polymer chains near the filler are controlled by the configurational entropy. In the case of strong polymer-filler interaction (equivalent to the hydrogen bond), the innerest adsorbed polymer segments still undergo adsorption-desorption process, the transport of chain mass center in the interfacial region exhibits away from the glassy behavior, and no plastic-like yielding point appears in the stress-strain curve, which indicates that although the mobility of interfacial polymer chains is restricted, there exist no "polymer glassy layers" surrounding the filler. In addition, it is evidenced that the filler particle prefers selectively adsorbing the long polymer chains for attractive polymer-filler interaction, validating the experimental explanation of the change of the bound rubber (BR). In short, this work provides important information for further experimental and simulation studies of polymer-nanoparticle interfacial behavior. © the Owner Societies 2011. Source


Wang W.,Beijing University of Chemical Technology | Li R.,Beijing University of Chemical Technology | Tian M.,Key Laboratory of Carbon Fiber and Functional Polymers | Liu L.,Key Laboratory of Beijing City on Preparation and Processing of Novel Polymer Materials | And 4 more authors.
ACS Applied Materials and Interfaces | Year: 2013

A facile method was developed to fabricate highly electrically conductive aramid fibers. The immobilization of silver nanoparticles on the surface of polymetaphenylene isophthamide (PMIA) fibers was carried out by the functionalization of the PMIA fibers with poly(dopamine), followed by electroless silver plating. The poly(dopamine) (PDA) layer was deposited on the PMIA surface by simply dipping the PMIA substrate into an alkaline dopamine solution. The silver ions can be chemically bound to the catechol and indole functional groups in PDA. The silver ions were reduced into silver nanoparticles by using glucose as the reducing agent, resulting in a distinct silver layer on the PMIA surface. The obtained silver deposit was homogeneous and compact. The chemical composition of the modified PMIA fibers was studied by X-ray photoelectron spectroscopy (XPS) and energy dispersive X-ray spectroscopy (EDS), and the crystalline structure of the silver-coated PMIA fibers was characterized by powder X-ray diffraction (XRD). The topography of the modified PMIA fibers was investigated by scanning electron microscopy (SEM). The four-point probe resistivity meter was used to study the electrical resistivity of the silver-coated PMIA fibers, the results indicated that the electrical resistivity could be as low as 0.61 mΩ·cm, with a controllable silver content, and a satisfactory stability by ultrasonic treatment. © 2013 American Chemical Society. Source

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