苯乙烯类热塑性弹性体

《化工反应工程》论文题目：苯乙烯类热塑性弹性体1目录论文题目：苯乙烯类热塑性弹性体······································································01.1简介··········································································································21.1.1发展历史····························································································21.1.2结构式·······························································································31.1.3分类··································································································41.1.4生产厂家····························································································51.2主要性能和应用···························································································61.2.1结构特性和主要物理性能·······································································71.2.1.1结构特性···················································································71.2.1.2主要物理特性·············································································81.2.2应用·································································································101.3国内外研究现状和进展·················································································121.3.1合成·································································································121.3.1.1线型三嵌段苯乙烯热塑性弹性体····················································131.3.1.2星型苯乙烯类热塑性弹性体··························································141.3.2生产工艺···························································································141.3.2.1极化改性工艺············································································141.3.2.2偶联剂技术···············································································151.3.2.3聚合工艺的改进·········································································151.3.2.4螺杆挤出法合成新工艺································································161.4展望·········································································································161.4.1苯乙烯类热塑性弹性体的技术进展··························································161.4.2未来发展趋势·····················································································171.4.2.1生产规模··················································································171.4.2.2应用方向··················································································181.4.2.3研究动向··················································································181.5小结·········································································································191.6参考文献···································································································1921.1简介热塑性弹性体(又称热塑性橡胶ThermoplasticElastomer/TPE)，由于兼有软质塑料的工艺加工性能和硫化橡胶的物理机械性能特性，故有“第三代合成橡胶”之称[1]。苯乙烯类热塑性弹性体（又称苯乙烯类嵌段共聚物StyreneicBlockCopolymers/SBCs），是目前世界上与橡胶性能最为相似、产量最大、发展最快的一种热塑性弹性体。苯乙烯类热塑性弹性体一般以烷基锂为引发剂，由苯乙烯、丁二烯或异戊二烯通过阴离子聚合技术制得。苯乙烯类热塑性弹性体按嵌段成分分为苯乙烯-异戊二烯-苯乙烯嵌段共聚物，苯乙烯-丁二烯-苯乙烯嵌段共聚物以及其相应的加氢产物[2～3]。苯乙烯类热塑性弹性体能和许多种材料混合，如增塑剂、改性剂、填料和其它树脂等。这种混合可根据特殊应用的需要，改变材料的多种性能，像软化温度、黏性、内聚粘结强度和刚性，因此苯乙烯类热塑性弹性体有着非常广泛的应用范围。1.1.1发展历史自从美国壳牌（Shell）化学公司在1965采用年以仲丁基锂为引发剂的阴离子聚合技术第一次实现SBC工业化生产以来，世界上对于SBC的开发应用开始迅猛发展。美国的科腾（Kraton）公司相继于1966年首先生产出苯乙烯-二烯类的嵌段共聚物，包括苯乙烯-异戊二烯-苯乙烯嵌段共聚物(Styrene-Isoprene-Styrene/SIS)和苯乙烯-丁二烯-苯乙烯嵌段共聚物(Styrene-Butadiene-Styrene/SBS)。到1972年，壳牌公司又生产了氢化苯乙烯–丁二烯–苯乙烯嵌段共聚物(Styrene-Ethylene-Butylene-Styrene/SEBS)，其中EB是指乙烯-丁烯共聚物嵌段。随着SBC的市场需求量不断增加，以及应用领域不断扩大，许多国家的石油化工企业都相继进行了SBC合成技术的研究开发和生产应用。进入21世纪以后，由于合成苯乙烯类热塑性弹性体的工业技术己经非常成熟，改善产品性能，在技术开发上竟争激烈，为了降低成本，各大公司在合成工艺、引发剂以及开发新牌号方面取得了新的进展。其中尤以SBS和SIS发展最快，到2009年为止，世界上生产SBS的厂家已达到有33家，其中有13家能同时生产SIS。其中，美洲有5家，欧洲有3家，日本有3家[4]。随着市场需求的快速增加，全球再一次掀起了热塑性弹性体投资的热潮，预计2013年苯乙3烯类嵌段共聚物全球市场需求将达到200万t，接近所有热塑性弹性需求的一半[2]，因此开发利用前景十分广阔。1.1.2结构式SBS属于苯乙烯类热塑性弹性体，是苯乙烯-丁二烯-苯乙烯三嵌段共聚物的简称。根据合成技术的不同，SBS有星型结构和线型结构，线型SBS的结构式为：星型SBS[(SB)nR]的结构式为：SIS的结构式为：SEBS的结构式为：SEPS的结构式为：4SEEPS的结构式为：式中x一般等于3或4；M表示硅或锡等，Y为氢原子(0或1)；X1，X2，Y1，Y2，n1，m2均是大于零的正整数。聚苯乙烯球形聚集区起交联点和补强粒子的作用。SBS属两相结构，因此有两个玻璃化转变温度Tg1(橡胶相)与Tg2(树脂相)。SBS的数均分子量一般不高于12万[5]。SBS的分子量对其性能有很大影响，分子量愈大，溶液粘度越大，粘接强度就愈高。SBS产品中的单体组成比也很重要，随着苯乙烯与丁二烯之比S/B的增大，聚合物溶液黏度变小，拉伸强度和硬度增大。SBS中的聚苯乙烯(PS)链段与聚丁二烯(PB)链段呈两相结构，PB为连续相，PS为分散相，互不相容，呈相分离状态。1.1.3分类目前，苯乙烯类热塑性弹性体根据聚合物的结构不同分为线型和星型两种类型；按性能差异可分为纯料（非充油型与充油型）和填充粒料（即混合料）两种类型；根据嵌段成分可分为苯乙烯-丁二烯-苯乙烯三嵌段共聚物（SBS）、苯乙烯-异戊二烯-苯乙烯三嵌段共聚物（SIS）以及它们对应的加氢产物--氢化的SBS（SEBS）和氢化的SIS（SEPS）四种类型[6]。依据各类硬段和软段的比例与分子量的差异，又可分为若干牌号。下面是一些常用苯乙烯类热塑性弹性体的英文简称：SBS：Styrene-Butadiene-Styrene(SBS)，苯乙烯-丁二烯-苯乙烯嵌段共聚物5SEBS：Styrene-Ethylene-Butylene-Styrene(SEBS)，氢化SBS，饱和型SBS，丁苯乙烯丁烯橡胶SBC：Styreneblockcopolymer(SBC)，苯乙烯类嵌段共聚物SEEPS：Styrene-Ethylene-Ethylene/Propylene-Styrene(SEEPS)，苯乙烯-[乙烯-(乙烯-丙烯)]-苯乙烯嵌段共聚物SIS：Styrene-Isoprene-Styrene(SIS)，苯乙烯-异戊二烯嵌段共聚物SEPS：Styrene-Ethylene-Propylene-Styrene(SEPS)，苯乙烯-乙烯-丙烯嵌段共聚物1.1.4生产厂家表12011年世界SBS主要生产厂家情况（万吨/年)[7]61.2主要性能和应用公司名称地址生产能力产品主要类型美国Kraton聚合物公司俄亥俄州Belpre20.0SBS/SEB/SSIS/SEPS美国Dexco聚合物公司路易斯安那州Plaquemine6.2SBS/SIS/SIBS美国LCY弹性体公司得克萨斯Baytown6.0SBS/SIS墨西哥Dynasol弹性体公司Altamira，Tamau