【作者】 孙良；

【导师】 王玉荣； 李杨；

【作者基本信息】 大连理工大学 ， 材料学， 2005， 硕士

【摘要】 本论文首次以环己烷为溶剂,异戊二烯(Ip)为增溶剂,四氢呋喃为反应速率调节剂,一定比例的二乙烯基苯(DVB)与六亚甲基亚胺基锂(LHMI)在一定的温度条件下反应制得官能化多锂引发剂。采用这种新型官能化多锂引发剂制备的聚合物兼具星型聚合物和官能化聚合物的特点,因而具有优异的滞后损耗性和加工性能。该官能化多锂引发剂在非极性溶剂中具有很好的溶解性能、较快的引发速度、溶剂体系单一、制备工艺简单、合成时间短、成本低等特点。采用所制得的官能化多锂引发剂引发丁二烯、异戊二烯、苯乙烯聚合,制备了星型聚丁二烯[N-(BR)_n]、聚异戊二烯[N-(IR)_n]、丁二烯—苯乙烯无规共聚物[N-(SBR)_n]三种不同的胶种,并对聚合反应过程动力学行为、热效应进行了较为系统的研究,对聚合物的微观结构、分子量及分布进行了较为深入的研究,同时对聚合物的物理机械性能进行了较为全面的研究。纵观全文,得到了如下结论:1.合成了官能化多锂引发剂,实践证明其具有原料价廉易得、制备工艺简单、溶解性好等特点。采用合成的官能化多锂引发剂引发丁二烯、异戊二烯、苯乙烯聚合,制备了星型聚丁二烯[N-(BR)_n]、聚异戊二烯[N-(IR)_n]、丁二烯—苯乙烯无规共聚物[N-(SBR)_n]。结果表明:控制一定的条件,该官能化多锂引发剂可实现聚合物的分子量设计,合成具有宽分布的星型聚合物。2.采用合成的官能化多锂引发剂成功地制备了星型聚丁二烯、聚异戊二烯均聚物。对两类聚合物在不同调节剂用量下的微观结构进行了研究,并测得了不同微观结构下的玻璃化转变温度;对聚合物的分子量及分布进行了研究,分析了DVB及TMEDA加入量对分子量分布的影响。3.对官能化星型聚丁二烯在不同引发温度、不同引发剂浓度和不同极性调节剂用量等条件下的动力学进行了详细的研究,求得了不同条件下假一级表观增长反应动力学常数k_p”、聚合反应在不同DVB用量下的表观活化能、表观增长反应速度常数k_p’以及反应的速率方程。4.采用官能化多锂引发剂实现丁二烯—苯乙烯二元共聚合,并对不同条件下聚合物的微观结构、玻璃化转变温度、分子量及分布、动态粘弹性和物理机械性能进行了详细的研究,结果表明这种新型溶聚丁苯橡胶抗湿滑性得到改善,滚动阻力大幅度下降。更多还原

【Abstract】 The functionalized multilithium initiator was prepared from commercial DVB and LHMI in proper temperature, which was reacted in cyclohexane solvent with isoprene for improving solubility and THF as polar additive for improving reaction speed. Polymer prepared by the novel functionalized multilithium initiator could exhibit improved characteristics such as reduced hysteresis loss characteristics and good processiblity. The functionalized multilithium has the advantage of good solubility in nonpolar solvent, fast initiation speed, single solvent system, simplified preparation technology, short synthesis time and low cost. The present thesis utilized the monomers of butadiene, isoprene and styrene to synthesize a series of novel polymers with prepared functionalized multilithium. Following were the typical star-shaped polymers as prepared, including polybutadiene, polyisoprene, copolymer of butadiene/styrene. Furthermore, this thesis also studied systematically the kinetic behavior and heat effect in the polymerization process. The microstructure, molecular weight and its distribution as well as the mechanical properties of the polymers mentioned above were also investigated in detail. From the summary of the full thesis, it came to the conclusions that:1. The functionalized multilithium initiator which featured of cheaper and easily available raw stuff and simple preparation technology was prepared. A series of novel polymers with the prepared functionalized multilithium as initiator, including polybutadiene, polyisoprene, copolymer of butadiene/styrene were synthesized. The results showed that the functionalized multilithium initiator could be used to realize the design for molecular weight of the polymers and get the molecular weight in dispersed distribution.2. The star-shaped polybutadiene and polyisoprene were successfully prepared with functionalized multilithium as initiator and the microstructure of them was investigated in detail under different polar additives dosage and the glass transition temperatures were obtained. The molecular weight and distribution of the two polymers were studied and analysed the influence on MWD of the DVB and TMEDA dosage. 3. The kinetic behaviors in the process of polybutadiene at different initiation temperature, different initiation concentration and different polar additives dosage were studied. And the pseudo first order values of propagation rate kp" under different conditions, the apparent activation energies under different DVB dosage, the apparent values of propagation rate k_p’ and the polymerization rate equation were obtained.4. The copolymerization of butadiene/styrene with functionalized multilithium as initiator was studied systematically. The microstructure, glass transition temperature, molecular weight and distribution, dynamic mechanical behaviour were also investigated in detail. It came to the conclusions that the novel SSBR initiated by the functionalized multilithium could exhibit both good wet skid resistance and low rolling resistance.更多还原