Papers by Keyword: Polystyrene

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Authors: Hiroki Uehara, Masaki Kakiage, Hidekazu Tanaka, Takeshi Yamanobe
Abstract: Structural deformation during uniaxial drawing of polyethylene-block-polystyrene (PE-b-PS) copolymer film was analyzed by in-situ small angle X-ray scattering (SAXS) measurement. The PE-b-PS film was prepared by solution casting, followed by isothermally crystallizing from melt. The obtained film exhibits the characteristic bicontinuous crystalline/amorphous morphology. Initial stage of uniaxial drawing induces the orientation of such crystalline/amorphous phases, but these phase separation is destroyed in the latter stage. In contrast, solvent swelling treatment successfully induces the orientation of crystalline/amorphous phases with keeping the phase continuity.
Authors: Sarah Kayfetz Outzen, Cheng Chen
Abstract: Concrete has one of the highest carbon footprints of building materials in use, and is also one of the most often used building materials in modern construction. Polystyrene is a non-biodegradable polymer in continued use. This paper examines the feasibility of using polystyrene beads in structural concrete. Recycled polystyrene beads were used as a coarse aggregate in concrete mixtures to explore possible structural application. Two samples apiece of three experimental mixes of concrete as well as control concrete mixtures were tested in the laboratory for density and compressive strength at 14, 28, 56 and 70 days curing. The laboratory testing showed one experimental mixture was of comparable compressive strength to the control concrete mixture. The experimental results demonstrated that recycled polystyrene concrete in volumetric percentages below 18.75% could be a feasible green concrete mixture.
Authors: Yuki Hongo, Kenji Sakai, Yuuki Sato, Shinzo Yoshikado
Abstract: A low-cost composite electromagnetic wave absorber made of sendust dispersed in resin was developed that does not contain any rare metals. In this study, spherical sendust particles with average particle sizes of approximately 5 and 20 μm were dispersed in polystyrene resin at volume ratios in the range 2040 vol% to broaden the absorption frequency bandwidth at frequencies above 10 GHz. The optimal volume ratios of sendust with average particle sizes of approximately 5 and 20 μm were found to be approximately 30 and 35 vol%, respectively. Electromagnetic wave absorbers can be flexibly designed by controlling the volume ratio of spherical sendust particles in resin.
Authors: Yan Xu, Wei Chen, Kai Leung Yung
Abstract: The most apparent advantages of thermoplastics are the recyclability and processibility. To obtain recyclable and injectable conductive polymer, this paper studied the filling of carbon nanotubes (CNT) in polystyrene(PS) and the aligning of CNT in PS under high frequency electric field and ultrasonic vibration using an experimental set up developed in our laboratory. Results of these studies would be very useful to the development of a new generation of micro fabrication method for producing integrated micro electronic products using micro injection molding that is the most cost effective way to produce micro products massively.
Authors: Xiu Yun Wang, Shunichi Uchiyama
Abstract: This paper describes recent advances in the development of bioelectrochemistry research which is focused on the advanced design and preparation of enzyme-based amperometric biosensors, as well as the functional structure and principle. Particular emphasis is directed to the discussion and exploration of electrochemical biosensors based on novel functional polymer, polymaleimidostyrene (PMS), as effective immobilization support and stabilizer. The sulphydryl and amino groups of enzymes react with maleimide groups of PMS. As a result, various enzymes can be easily modified on the electrode surface. First topic is PMS-based enzyme-micelles which are dispersed in the polystyrene film prepared on the electrode surface. The structure and morphology of enzyme-micelles membranes were characterized by scanning electron microscope. Second topic is bio-functionalization of electrode surface using enzyme-immobilized PMS. Electrochemical and bioelectrocatalytic properties of enzyme-micelle membranes were examined by various electrochemical techniques. These enzyme-micelle-based electrochemical biosensors exhibited good sensitivity and selectivity for the detections of urea, uric acid, L-ascorbic acid, glucose and toxic phenol compounds. The prospects and further developments in this exciting interdisciplinary field are also suggested.
Authors: Qamar Nawaz, Y. Rharbi
Abstract: The effects of nanoconfinement on the dynamic and the glass transition (Tg) of polymers remains the focus of a lot of research since over a decade. Particularly, the glass transition temperature (Tg) and the dynamic of polystyrene (PS) were found to be altered by nanoconfinement in thin films and on the bulk free-surface. However, the dynamic of polymer nanoconfined in nanoparticles has not been investigated, even though the close-packed nanoparticle geometry is commonly used in many applications such as waterborne coatings. We investigate the dynamic of polystyrene in nanoparticles by monitoring the closure of voids (interstices) between PS nanoparticles in the close-packed structure. Void-closure during the passage from the close-packed particles to bulk PS is monitored using small angle neutron scattering at the bulk Tg (100 °C). The relaxation time (τ) and the apparent viscosity (η) of nanoconfined polystyrene estimated from the void-closure decay is found to decrease only by ~2 times for particle diameters between 93 nm and 42 nm. These results infer that dynamic of nanoconfined PS in nanoparticles at the bulk Tg is not different from that of bulk polystyrene.
Authors: A. Takahara, X. Jiang, N. Satomi, Kenji Tanaka, T. Kajiyama
Authors: Anton Valkov, Faina Nakonechny, Marina Nisnevitch
Abstract: Photosensitizers immobilized in polymers can serve as antibacterial surfaces or coatings and can be applied for disinfection of water or medical instruments. The antibacterial activity of the immobilized photosensitizers is based on their excitation by visible light followed by energy transfer from the photosensitizers to oxygen dissolved in an aqueous phase which produces reactive oxygen species that cause irreversible damage to bacterial cells. The photosensitizer Rose Bengal immobilized in polystyrene, polycarbonate and poly (methyl methacrylate) was shown to eradicate Gram-positive Staphylococcus aureus bacteria under moderate illumination.
Authors: Fan Lin Zeng, Yi Sun
Abstract: The influences of the polyhedral oligomeric silsesquioxane (POSS) on the mechanical properties of the polystyrene (PS) under tensile strain loading were studied using the atomistic finite element simulations. Firstly, the nano scale pole-like atomistic models and the micro scale pole-like finite element models of two kinds of homopolymers, the pure PS and the polystyrene attached with 5 mol% propyl-POSS (P-POSS-PS), were built, after which the atomistic finite element models were built by connecting the carbon and silicon atoms on the boundaries of the atomistic models to the corresponding nodes in the finite element ones. Then the mechanical behaviors of the two kinds of homopolymers under different tensile strains were investigated. The results show that, when the tensile strain of PS reaches 0.05 the micro voids appear. The tensile stresses of PS approximatively keep increasing with the increasing strain before the tensile strain of 0.07, after which the stresses declines. And the corresponding tensile modulus of PS is 4.52GPa. By contrast with PS, when the tensile strain of P-POSS-PS reaches 0.06 the micro voids appear. The tensile stresses of P-POSS-PS are almost keeping increasing before the tensile strain of 0.08, and the corresponding tensile modulus is 5.32GPa. Conclusions can be made from this work that the tensile strength of homopolymers can be observably improved by POSS. A small quantity of POSS can even improve the toughness of homopolymers slightly. This work has realistic theoretical significance to understand the reinforcement mechanism of POSS and provides important referential message to the applications of POSS.
Authors: Seung Hun Kim, K.K. Lee, Han Seung Lee, K.J. Lee, In Seok Kang
Abstract: Where the self weight of the overall slab needs to be considered, the quantity of in-situ concrete required can be reduced by the introduction of polystyrene void forms supplied and fixed to the precast panel during manufacture. In this study, new I-slab system with polystyrene form and precast concrete deck is proposed to reduce the construction period and the self weight of the slab. This paper presents experimental works on the bending and shear of the I-slabs. Five specimens were tested. The main parameters of experiments were the hole diameter of polystyrene form and the thickness of slab. Structural performance of I-slab was evaluated on the basis of failure mode, load-displacement curve, and ultimate strengths. Based on the test results, the critical punching shear sections were changed as test variables, so the punching shear strengths were very different. Test results indicated that the developed I-slab were very effective to increase the strength because of self weight reduction.
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