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1.
Arissara Ratcha Chanatip Samart Boonyawan Yoosuk Hideo Sawada Prasert Reubroycharoen Suwadee Kongparakul 《应用聚合物科学杂志》2015,132(42)
Biorenewable polyisoprene latex obtained from natural rubber, Hevea brasiliensis, was used to prepare the reusable polyisoprene–poly(alkyl acrylate) foam for petroleum‐based liquid absorption. The foam was produced via latex vulcanization and cured by steaming. The effect of various types of poly(alkyl acrylate) such as poly(methyl methacrylate) (PMMA), poly(butyl methacrylate) (PBMA), and poly(butyl acrylate) (PBA) on oil sorption capacity of the foam were studied. Scanning electron microscope (SEM) images showed interconnected open‐cell macrostructure with the foam porosity greater than 75% and good compression set. The oil sorption capacity of the foam was in the range of 2.0–16.6 g g?1. The addition of poly(alkyl acrylate) enhanced hydrophobicity and oil sorption capacity of the foam. The absorbed oil was easily recovered by squeezing and the foam can be reused up to 30 sorption–desorption cycles and still preserve high quality sorption. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42688. 相似文献
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Summary The polyisoprene block of a
polyisoprene-polydimethylsiloxane (PI-PDMS) diblock copolymer
with 0.68 volume fraction of PI was tightly crosslinked with
dicumylperoxide. The PDMS part of the obtained glassy material
was subsequently quantitatively etched with anhydrous hydrogen
fluoride or tetrabutylammonium- fluoride, in this way obtaining
a nanoporous material. The fraction of the surviving double
bonds was estimated by solid state NMR, while thermal analysis
was used to characterize the glass transition temperature of PI
as a function of crosslinking degree. Small angle x-ray
scattering confirmed the existence of microphase separated
cylinders of PDMS in a PI matrix and its conservation in the
form of channels in the crosslinked matrix. 相似文献
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Polystyrene is not normally shear-modifiable. Addition of small amounts of plasticizer (butyl benzyl phthalate) result in changes in melt viscosity and elasticity during extrusion. Fiber spinning experiments are shown to provide useful indications of the rheological state of polymers that are sensitive to shear history. Here, the density, modulus and work to rupture of lightly plasticized polystyrene is shown to vary with extrusion history of the material. 相似文献
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纯PS改性沥青的储存稳定性较差,SBS和反应剂的加入减小了PS改性沥青的颗粒尺寸,有利于PS的分散,提高了PS改性沥青的储存稳定性。 相似文献
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研究了复合橡胶对高抗冲聚苯乙烯(HIPS)结构与性能的影响,并用透射电子显微镜对HIPS进行了表征。结果表明:低顺聚丁二烯橡胶(简称低顺橡胶)能增加HIPS橡胶相体积分数,使橡胶粒子形态分布更均匀;高顺聚丁二烯橡胶(简称高顺橡胶)有利于提高产品的韧性;低顺橡胶对HIPS弯曲强度和拉伸强度的增加贡献更大;采用高顺橡胶与低顺橡胶复合,能够协调HIPS的韧性、弯曲强度和拉伸强度。 相似文献
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The poor impact resistance of Polystyrene (PS) was enhanced by the addition of elastomeric material, SEBS‐g‐MA. To prevent the reduction in strength and stiffness, organoclay Cloisite® 25A was used as filler and introduced into the matrix by a corotating twin screw extruder. Throughout the study, the clay content was kept at 2 wt%, whereas the content of SEBS‐g‐MA was varied between 5 and 40 wt%. It was found that Cloisite® 25A displays well dispersion in the ternary nanocomposites and the degree of dispersion increases with the elastomer content. The elastomeric phase has a greater viscosity than pure PS. Thus, as expected, at low elastomer contents, it forms the dispersed phase in the matrix as droplets. Transmission electron microscopy results show that the clay layers reside at the interphase between PS and elastomer and also inside the elastomeric phase. Owing to the location of the clay particles, the average elastomer domain size in ternary nanocomposites are found to be greater than that in the relative binary blends of PS‐(SEBS‐g‐MA). Moreover, with the organoclay addition, phase inversion point shifts to lower elastomer contents. The mechanical test results showed that the nanocomposites containing 15 and 20 wt% SEBS‐g‐MA have the optimum average domain size that results in high‐impact strength values without deteriorating the tensile properties. POLYM. COMPOS., 31:1853–1861, 2010. © 2010 Society of Plastics Engineers. 相似文献
8.
改性聚苯乙烯塑料件电镀仿金工艺 总被引:1,自引:2,他引:1
本文提出了改性聚苯乙烯塑料件电镀仿金的工艺组合, 相应的工艺规范和操作要求,所得仿金镀层成色为18~22K金色,色泽均匀,结合力好。 相似文献
9.
S. A. Telenkov Yingxia Wang Yuesheng Lu L. D. Favro P. K. Kuo R. L. Thomas 《Polymer Engineering and Science》1998,38(3):385-391
The plastic yield and fracture of rubber-modified polystyrene specimens under tensile load have been investigated at room temperature. The experimental procedure consisted of rapidly alternating measurements of transmitted and emitted infrared (IR) radiation from samples under tensile stress. The load-displacement data were simultaneously recorded. Both single-edge-notched and dog bone-shaped test coupons were studied. In each tensile test run, we observed a significant decrease of material transparency in the IR which occurred near the low yield point. A further increase in material deformation was accompanied by a substantial temperature increase. After material failure, the surface morphology of the test specimens in the vicinity of the crack was examined using atomic force microscopy (AFM). Our results are explained in the context of existing models of material crazing. 相似文献
10.
Mustafa M. F. Al-Jarrah Jawad K. H. Al-Kafaji Rita L. Apikian 《Polymer International》1986,18(4):256-258
Styrene was grafted from polyisoprene forming poly(isoprene-g-styrene) graft polymers. N,N,N',N'-Tetramethylene diamine and s-butyllithium were used to create active centres on the polyisoprene backbone in cyclohexane under anionic living polymerisation conditions. The stereoregularity of polyisoprene is shown to influence the grafting efficiency. Addition of small amounts of tetrahydrofuran increased grafting efficiency and decreased polydispersity of the graft polymers obtained. Polystyrene branches are shown to be syndiotactic rich. 相似文献
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Blends of polypropylene (PP) and modified atactic polystyrene (PS) with good processability were studied for dyeable fine and superfine fibers. Acrylic acid and butyl acrylate monomers were added to PS by radical suspension copolymerization. The dispersion of the additives in the PP crystal was investigated. The rheology curves of the blends were similar to that of PP under the testing conditions. Fine and superfine PP filaments were processed from these blends, and they had practical mechanical properties. The dyeability of the fabrics from the fibers was studied. The increased amorphous content and the interface between PP and modified PS allowed the dyes to penetrate the fibers. These two effects helped to improve the color intensity. The color fastness was also improved by the presence of polar groups introduced by the modified PS components. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 2360–2366, 2005 相似文献
14.
Vinylbenzyl chloride was allowed to react with a low‐molecular‐weight oligomer of butadiene in order to give a material that could then be used to alkylate an amine to form an ammonium salt. This ammonium salt was ion‐exchanged onto a clay to give a new organically modified clay, which was used to prepare polystyrene‐clay nanocomposites by solution and bulk polymerization and by melt blending. The nanocomposites were characterized by using X‐ray diffraction, transmission electron microscopy, thermogravimetric analysis, cone calorimetry, and the evaluation of mechanical properties. These systems show good nanodispersion and improvement in thermal and mechanical properties. J. Vinyl Addit. Technol. 10:44–51, 2004. © 2004 Society of Plastics Engineers. 相似文献
15.
液体聚异戊二烯的结构表征 总被引:5,自引:0,他引:5
通过傅立叶变换红外光谱、核磁共振、不饱和度测定、凝胶渗透色谱、热重分析和动态流变分析等手段对液体聚异戊二烯(LIR-50)的结构及其基本性质进行了研究.结果表明,LIR-50的链节化学组成与天然橡胶完全相同,但二者的空间结构有明显区别.LIR-50的顺-1,4、反-1,4和3,4结构含量分别为70.8%、24.4%、4.8%,而天然橡胶的顺-1,4结构高达98%.LIR-50的数均分子量为42000,多分散指数为1.24,其动态粘度对温度敏感,对剪切速率不敏感. 相似文献
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The pyrolysis of polyisoprenes with 1,4 and 3,4-units occurs in an analogous way as the pyrolysis of polybutadienes with 1,4 and 1,2 units. 相似文献
17.
Hongyang Yao Jin Zhu Charles A. Wilkie Alexander B. Morgan 《Polymer Engineering and Science》2002,42(9):1808-1814
Crown ether‐modified clays were obtained by the combination of sodium and potassium clays with crown ethers and cryptands. Polystyrene nanocomposites were prepared by bulk polymerization in the presence of these clays. The structures of nanocomposites were characterized by X‐ray diffraction and transmission electron microscopy. Their thermal stability and flame retardancy were measured by thermogravimetric analysis and cone calorimetry, respectively. Nanocomposites can be formed only from the potassium clays; apparently the sodium clays are not sufficiently organophilic to enable nanocomposite formation. The onset temperature of the degradation is higher for the nanocomposites compared to virgin polystyrene, and the peak heat release rate is decreased by 25% to 30%. 相似文献
18.
Hui Du Yuhua Zhao Ning Yin Qifeng Li Junwei Wang Maoqing Kang Hongwei Xiang Xinkui Wang 《应用聚合物科学杂志》2008,110(5):3156-3161
Waterborne polyurethane (WPU) adhesives modified by polystyrene (PS) were prepared through a prepolymer mixing process from diisocyanates, an anionic polyester, internal emulsifiers, a neutralizer, a chain extender, and PS dispersions. The latter was preformed via the in situ polymerization of styrene in poly(1,4‐butanediol adipate) diol. Transmission electron microscopy, Fourier transform infrared spectroscopy, and 1H‐NMR techniques were used to characterize the PS dispersions and polyurethane (PU)–PS prepolymer. Experimental results with respect to the performance of the PU–PS adhesives indicate that suitable PS/polyester diol weight ratios improved the mechanical properties, thermal stability, water resistance, and initial adhesive strength of the pristine WPU adhesives. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
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采用种子乳液聚合法制备了具有核壳结构的聚丁二烯接枝聚苯乙烯(PB-g-PS),并将其与沥青通过高速剪切共混制备了PB-g-PS改性沥青,考察了PB-g-PS改性沥青的物理性能以及热老化性能、感温性、热贮存稳定性和相容性。结果表明,当PB-g-PS的质量分数为5%时,改性沥青的高温热稳定性、抗低温开裂性较好;与基质沥青相比,改性沥青的热老化性能得到改善,感温性下降;在相同条件下,PB-g-PS改性沥青的热贮存稳定性要好于苯乙烯-丁二烯-苯乙烯嵌段共聚物改性沥青;核壳结构的PB-g-PS与基质沥青具有一定的相容性。 相似文献