SBS/P(St-MMA)热塑性互穿聚合物网络结构与力学性能

采用原子转移自由基聚合(ATRP)法合成了苯乙烯一甲基丙烯酸甲酯共聚物[P(St-MMA)]。采用分步法制备了SBS／P(St-MMA)热塑性互穿聚合物网络(TIPN)。研究了P(St-MMA)质量分数、MMA／St(摩尔比,下同)和不同聚合方式对TIPN结构和力学性能的影响。结果表明：生成了具有较窄相对分子质量分布的P(St-MMA);P(St-MMA)质量分数在30％,左右时,采用ATRP法制备的SBS／P(St-MMA)TIPN拉伸强度和扯断伸长率达到最大;随MMA／St增加,TIPN拉伸强度增大,扯断伸长率不变。常规自由基聚合法制备的TIPN与ATRP法相比,前者相对分子质量高,相对分子质量分布宽,拉伸强度高,扯断伸长率随P(St-MMA)质量分数增加而下降。     

苯乙烯-丁二烯-苯乙烯嵌段共聚物/聚(苯乙烯- 甲基丙烯酸甲酯)热塑性互穿聚合物网络

采用原子转移自由基聚合(ATRP)和分步方法,制备了以苯乙烯-丁二烯-苯乙烯嵌段共聚物(SBS)为聚合物Ⅰ,聚(苯乙烯-甲基丙烯酸甲酯)[P(St—MMA)]为聚合物Ⅱ的SBS／P(St—MMA)热塑性互穿聚合物网络(TIPN)。研究了P(St—MMA)质量分数、MMA／St(摩尔比)和不同聚合方式对TIPN动态力学性能和黏结性能的影响。结果表明,采用ATRP法制备的TIPN的动态力学性能和黏结性能均优于常规自由基聚合制备的TIPN。高温区聚苯乙烯(PSt)嵌段的玻璃化转变温度明显降低,而损耗角正切tanδ2显著增加;TIPN的黏结性能也得到明显改善,拉伸剪切强度提高了3倍多。     

用原子转移自由基聚合法制备SBS/聚(苯乙烯-甲基丙烯酸丁酯)互穿聚合物网络

将线型热塑性弹性体SBS溶胀于苯乙烯和甲基丙烯酸丁酯混合液中,以BPO为引发剂,在CuCl/2,2′－联吡啶酯位化合物催化下进行原子转移自由基聚合,制备了SBS／聚（苯乙烯－甲基丙烯酸丁酯）互穿聚合物网络。结果表明,实现了苯乙烯－甲基丙烯酸丁酯共聚物的可控聚合,聚合物数均相对分子质量随单体转化率的提高呈线性增长,且分布较窄,从而得到了组成和性能不同的互穿聚合物网络。     

SBS热塑性弹性体混合料的性能研究

报道了SBS热塑性弹性体混合料的性能研究。探讨了软化油、聚苯乙烯(PS)、填料含量以及填料品种、化学交联对材料性能的影响,比较了SBS星形结构和线形结构及其并用对材料性能的影响。结果表明:化学交联对材料性能影响甚微;星形结构具有较高的撕裂强度,线形结构具有较高的拉伸强度和硬度;软化油含量对材料性能影响较大;轻质碳酸钙使材料具有最高的性能价格比,白碳黑填充材料的综合性能最佳。     

SBS／聚（苯乙烯－甲基丙烯酸盐）热塑性IPN熔体的流动性能

考察了组成、共混方法、温度、切变速平等因素对ＳＢＳ／聚（苯乙烯－甲基丙烯酸盐）热塑性互穿聚合物网络（ＩＰＮ）熔体流动性能的影响。结果表明，该热塑性ＩＰＮ熔体随着ＳＢＳ含量的增加，流动活化能降低；在不同的切变速率下，其表现粘度高于母体聚合物，也高于组成相似的由机械共混制备的热塑性ＩＰＮ；当ＳＢＳ含量为４０％时，其表观粘度出现极大值。     

聚(苯乙烯-co-丙烯腈)-b-聚苯乙烯两嵌段共聚物的合成

以CuBr／N，N，N’，N’，N'-五甲基二亚乙基三胺(简称NNN)为催化体系，研究了原子转移自由基聚合法(ATRP)PS-b-P(S-co-AN)两嵌段聚合物的合成。研究了聚合顺序对相对分子质量及其分布和嵌段效率的影响，并且用聚合物末端C—Br键的断裂能对实验结果进行了初步解释。     

PP/SBS热塑性弹性体复合材料的性能研究

研究热塑性弹性体苯乙烯-丁二烯-苯乙烯嵌段共聚物(SBS)填充聚丙烯(PP)所得的复合材料.首先制备不同含量SBS的复合材料;然后对所制备的各组复合材料进行理化性能测试,选出综合性能最好的一组,得到最佳含量的填充工艺.实验结果表明:在PP中加入SBS后,复合材料的冲击强度、拉伸强度等均得到了有效的提高,综合性能优于纯PP.     

相转移催化剂对苯乙烯-丁二烯-苯乙烯嵌段共聚物环氧化反应的影响(英文)

研究了三辛基甲基氯化铵(MTAC)、三十二烷基三甲基氯化铵(TMAC)、十六烷基三甲基溴化铵(HTAB)、十八烷基三甲基溴化铵(OTAB)以及聚乙二醇(PEG-400)等5种相转移催化剂对苯乙烯-丁二烯-苯乙烯嵌段共聚物环氧化反应的影响.结果表明,MTAC的环氧化效果最好,当其质量分数为1.0%时,可使环氧化苯乙烯-丁二烯-苯乙烯嵌段共聚物(ESBS)的环氧基质量分数从18.1%提高到20.1%;HTAB和PEG-400有利于ESBS的环氧基质量分数的提高;而OTAB和TMAC由于自身较大的分子体积反而使ESBS的环氧基质量分数下降.傅里叶变换红外光谱分析表明,MTAC可以有效抑制环氧基开环副反应的发生.     

SBR/P(St-MMA-AN)互穿网络聚合物的加工和力学性能

以丁苯胶乳为种子乳液，苯乙烯、甲基丙烯酸甲酯、丙烯腈的混合物为硬单体，二乙烯基苯为交联剂，在氧化还原引发体系下，以种子乳液聚合法得复合乳液，絮凝干燥后得到共聚物。研究了硬单体用量、硬单体配比、加工次数对聚合物力学性能的影响规律。结果表明，聚合物可反复进行热塑性加工，聚合物微观相畴随加工次数增多而变小。     

苯乙烯-丙烯酸甲酯共聚物增容对聚乳酸/SBS共混物结晶行为的影响

研究了苯乙烯-丙烯酸甲酯无规共聚物(SMA)增容剂对聚乳酸(PLA)与苯乙烯-丁二烯-苯乙烯嵌段共聚物(SBS)共混物的结晶行为的影响。通过熔融共混的方法制备了PLA/SBS (m_(PLA)∶m_(SBS)=95∶5)和PLA/SBS/SM A (m_(PLA)∶m_(SBS)∶m_(SM A)=95∶5∶3)共混物,使用扫描电子显微镜(SEM)、差示扫描量热仪(DSC)和偏光显微镜(POM)研究了SM A增容PLA/SBS共混物的形貌、非等温结晶行为、等温结晶行为和晶体形貌。结果表明,SBS的增塑效应和异相成核效应对PLA的非等温结晶和等温结晶行为有促进作用;而SMA的加入起到了降低SBS分散相尺寸的作用,同时阻碍了SBS对PLA结晶行为的促进作用。增容剂SMA阻碍SBS对PLA基体结晶行为促进作用的可能原因在于SMA在PLA和SBS界面处的阻隔作用导致两者接触面积减少,且SMA对PLA的结晶没有促进或抑制作用。     

Preparation of SBS/poly(styrene–methyl methacrylate) thermoplastic interpenetrating polymer network

SBS as polymer I, poly(styrene–methyl methacrylate) polymerized by atom transfer radical polymerization as polymer II, and a thermoplastic interpenetrating polymer network of SBS/poly(styrene–methyl methacrylate) were prepared by the sequential method. The effects of the polymerization temperature, the composition of the catalyst, the ratio of the monomers studied, and the kinetics at 90°C were also investigated. It was shown that when polymerization was initiated by a BPO/CuCl/bpy (BPO:CuCl:bpy = 1:1:3) system at 90°C, the mass averaged molecular weight of the poly(styrene–methyl methacrylate) increased with monomer conversion, and the polydispersities were kept very low. Fourier transform infrared spectroscopy and gel permeation chromatogram showed that poly(styrene–methyl methacrylate) with low polydispersities had been synthesized. Thus, a thermoplastic interpenetrating polymer network comprised of both narrow molecular‐weight‐distribution components was successfully prepared. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 2007–2011, 2003     

EA/St-AN互穿聚合物网络的加工和力学性能

以丙烯酸乙酯为软单体 ,苯乙烯和丙烯腈为硬单体 ,二乙烯基苯或三乙二醇双丙烯酸酯为交联剂 ,采用多步种子乳液聚合技术制备了半互穿和全互穿聚合物网络 ,研究了软、硬单体配比 ,交联剂用量 ,加工次数对共聚物流变行为、力学性能和结构形态的影响。结果表明 ,制备的半互穿和全互穿聚合物网络均可在适宜的条件下流动成型。如果配方选择适当 ,反复加工后力学性能基本不变     

聚苯乙烯/聚丙烯酸丁酯自交联胶乳互穿聚合物网络的力学性能和动态力学性能

采用种子乳液聚合制备了聚苯乙烯/聚丙烯酸丁酯自交联胶乳互穿聚合物网络。拉伸实验结果表明,用双丙酮丙烯酰胺和己二酸二酰肼自交联的胶乳互穿聚合物网络(LIPN)比相应的胶乳互穿聚合物网络具有较高的拉伸强度,并且随双丙酮丙烯酰胺用量的增加,拉伸强度增加以及永久变形降低,但离子键和氢键交联的LIPN具有很高的扯断伸长率和很大的永久变形,这些说明用双丙酮丙烯酰胺和己二酸二酰肼界面共价键交联能很好地改善力学性能和抗蠕变性能。动态力学谱结果表明,用双丙酮丙烯酰胺和己二酸二酰肼交联的LIPN比相应的LIPN以及离子键和氢键交联的LIPN具有较好的组分相容性和阻尼性能。     

Curing and mechanical properties of dicyanate/poly(ether sulfone) semi‐interpenetrating polymer networks

Semi‐interpenetrating polymer networks (semi‐IPNs) composed of a dicyanate resin and a poly(ether sulfone) (PES) were prepared, and their curing behavior and mechanical properties were investigated. The curing behavior of the dicyanate/PES semi‐IPN systems catalyzed by an organic metal salt was analyzed. Differential scanning calorimetry was used to study the curing behavior of the semi‐IPN systems. The curing rate of the semi‐IPN systems decreased as the PES content increased. An autocatalytic reaction mechanism was used to analyze the curing reaction of the semi‐IPN systems. The glass‐transition temperature of the semi‐IPNs decreased with increasing PES content. The thermal decomposition behavior of the semi‐IPNs was investigated. The morphology of the semi‐IPNs was investigated with scanning electron microscopy. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1079–1084, 2003     

Synthesis of block copolymers with thermodynamically compatible chain segments: di‐ and triblock copolymers of polystyrene and poly(2,6‐dimethyl‐1,4‐phenylene oxide)

Mono‐ and bifunctional poly(phenylene oxide) (PPO) macroinitiators for atom transfer radical polymerization (ATRP) were prepared by esterification of mono‐ and bishydroxy telechelic PPO with 2‐bromoisobutyryl bromide. The macroinitiators were used for ATRP of styrene to give block copolymers with PPO and polystyrene (PS) segments, namely PPO‐block‐PS and PS‐block‐PPO‐block‐PS. Various ligands were studied in combination with CuBr as ATRP catalysts. Kinetic investigations revealed controlled polymerization processes for certain ligands and temperature ranges. Thermal analysis of the block copolymers by means of DSC revealed only one glass transition temperature as a result of the compatibility of the PS and PPO chain segments and the formation of a single phase; this glass transition temperature can be adjusted over a wide temperature range (ca 100–199 °C), depending on the composition of the block copolymer. Copyright © 2005 Society of Chemical Industry     

Uralkyd and poly (butyl methacrylate) interpenetrating polymer networks

ABSTRACT:: Hydroxyl terminated alkyds synthesized from castor oil, glycerol, and different dibasic acids were used to develop uralkyds and their interpenetrating polymer networks (IPNs) with polybutyl methacrylate (PBMA). Glass transition temperature measurements gave the evidence of interpenetration. The IPNs were characterized for their physicomechanical properties and their phase morphology was studied by scanning electron microscopy (SEM) and differential scanning calorimetry (DSC). As the concentration of the uralkyd in IPNs increases, a gradual increase in elongation, density, and swelling with a consequent decrease in the hardness were observed for all IPNs. Swelling is relatively more prominent in methyl ethyl ketone (MEK) and toluene than in water. From SEM it was observed that IPNs of PBMA‐uralkyd containing phthalic anhydride (UA‐P) as an acid part showed greater compatibility than those containing dimethyl terephthalate (UA‐D). From thermogravimetric analysis (TGA) no significant change was observed in the degradation behavior of the IPNs. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 75: 825–832, 2000     

Effects of polyurethane soft segment and crosslink density on the morphology and mechanical properties of polyurethane/poly(allyl diglycol carbonate) simultaneous interpenetrating polymer networks

Tough, optically clear simultaneous interpenetrating polymer networks (SINs) of polyurethane (PU) and poly(allyl diglycol carbonate) (ADC) at different compositions were synthesized. The effects of the molecular weight of PU soft segment on the morphology, mechanical properties, and thermal transition behavior of the SINs at two levels of crosslinking agent were studied. The miscibility of PU/ADC SINs, studied by TEM and DMA, was greatly influenced by the SIN composition and the molecular weight of poly(caprolactone) diol (PCL) as the PU soft segment. A single‐phase morphology at a PU concentration of 10% changed to a very fine microheterogeneous morphology as the molecular weight of PCL changed from 530 to 1250. The two‐phase morphology of the PU10/ADC90 SIN based on higher PCL molecular weight (PCL 1250) was also confirmed by DMA, which displayed a sharp peak for the ADC‐rich phase and a small shoulder for the PU‐rich phase transition in the tan δ plot. The SINs at 20–30% PU composition exhibited co‐continuous phase morphology in the transmission electron micrographs, in which the phase regions grew larger as the PCL molecular weight increased from 530 to 1250. All the SIN samples possessed excellent optical transparency except two samples with 30% PU composition based on PCL 1250, which showed a hazy appearance. The tensile strength, modulus, and toughness of the SINs decreased by increasing the molecular weight of PCL from 530 to 1250, whereas the elongations at break remained nearly unchanged. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 1583–1595, 2003     

Water sorption of poly(vinyl alcohol)/ poly(diallyldimethylammonium chloride) interpenetrating polymer network hydrogels

Temperature‐responsive interpenetrating polymer network (IPN) hydrogels constructed with poly(vinyl alcohol) and poly(diallyldimethylammonium chloride) using the sequential IPN method were studied. The characteristics of IPN hydrogels were investigated using the dynamic vapor sorption system. IPN hydrogels exhibited a relatively high sorption ratio, 180–360% at room temperature. The sorption ratio of hydrogels depended on temperature. Diffusion coefficients were calculated according to the Fickian Law at several temperatures. The apparent activation energy was 5.43 kJ mol^?1, which corresponds to typical diffusion processes. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1389–1392, 2003