【作者】 余金光；

【导师】 韩丙勇；

【作者基本信息】 北京化工大学 ， 材料科学与工程， 2012， 硕士

【摘要】 本论文采用溶液铸膜的方法，制备了不同的SBS共混物，分别为SBS/SEBS共混物——研究软相结构对SBS性能的影响，和不同分子量SBS共混物——研究软相分子量对SBS结构和性能的影响。研究发现SBS与SEBS不能完全互溶，共混物出现宏观相分离，共混物的拉伸强度比纯聚合物的低，SEBS含量高时，共混物拉伸强度下降较小。不同分子量SBS可在分子水平互溶，与纯SBS相比，共混SBS的力学性能也降低。实验结果表明：苯乙烯（St）含量、聚丁二烯（PB）结构和分子量是影响SBS网络规整性最基本的三个因素，并进一步影响到SBS的力学性能：St含量增加，SBS拉伸强度提高；PB相分子量增大，SBS定伸应力降低；PB分子量分布越窄，SBS的网络结构越规整，力学性能越高。论文第二部分制备了两种杂化材料，分别为SBS-SiO₂杂化材料和PSB-SiO₂杂化材料，研究SiO₂接枝改变SBS的PS相和PB相对SBS性能的影响，结果表明：二氧化硅的存在会限制SBS分子链的运动，导致PS相区形成困难，强度下降；二氧化硅对PB相作用较强，SBS定伸应力提高；PB相玻璃化温度提高，tan峰值降低。PSB-SiO₂杂化材料的拉伸强度达7-8MPa，其中含10%SiO₂的杂化材料拉伸强度8.2MPa，300%定伸应力4.3MPa。论文最后对一种新的SBS极性化方法做了探索性研究。以二苯甲酮为封端剂，采用阴离子聚合的方法，制备一种聚丁二烯大分子引发剂，并引发甲基丙烯酸甲酯聚合，得到双亲嵌段共聚物。低温下二苯甲酮的封端率较高，嵌段聚合较适宜的条件为85℃下反应5h。更多还原

【Abstract】 Different SBS blends, SBS/SEBS blends and blends of differentmolecular weight SBS, were prepared via solvent casting membrane, tostudy the influence of softpahse structure and molecular weight on theproperties of SBS. The study showed that the mixtures of SBS andSEBS were in a macro phase-separated structure, the tensile strength ofblends were reduced compared to neat SBS or SEBS. While SBS ofdifferent molecular weight couled mixed on the molecular level andform microphase separation. Howerer, the mechanical properties ofblends decreased too. The result was: the content of St, the structure andthe molecular weight of PB were three main factors which influence theproperties of SBS, the change rule is: tensile stress increased with thevolume fraction of PS increasing, and the100%tensile stress（σ100） and300%tensile stress（σ300） lowed when the molecular weight of PBenlarged.Two hybrid materials, SBS-SiO₂hybrid materials and PSB-SiO₂hybrid materials were prepared. The result indicated that the existence ofsilica would limit the movement of SBS chain, and lead to a difficulty toform PS phase, so the properties of SBS decreased; interaction betweensilica and PB phase was stronger; the glass transition temperature of PB phase was improved, and dynamic loss tangent increased. PSB-SiO₂hybrid materials had a tensile stress about7-8MPa. When the content ofSiO₂was10%, the hybrid material’s tensile strength was8.2MPa, whileσ300was4.3MPa.In the end of this paper, a new method to prepare polarized SBSwas studied exploringly. A PB macroinitiator end-capped withbenzophenone was synthesized via anionic polymerization using n-BuLias initiator, and PB-block-PMMA copolymer was prepared use the PBmacroinitiator. The result showed that the end-capped efficiency waslower as the temperature increased; a better reaction condition whencopolymeratized was a reaction temperature of85℃for5h.更多还原