【作者】 马红卫；

【导师】 李杨； 张春庆；

【作者基本信息】 大连理工大学 ， 高分子材料， 2011， 博士

【摘要】 活性阴离子聚合是合成分子量以及分子结构可控窄分布聚合物的最有效方法。近些年来,研究人员广泛利用这一方法合成了多种结构新颖、应用前景广阔的新型聚合物。由于阴离子聚合反应的活性种对反应体系中的水、氧等杂质非常敏感,在实验方法方面有着严格要求,而全玻璃式高真空实验方法能够使反应体系绝对封闭,彻底杜绝外界影响,因此成为阴离子聚合理论研究不可或缺的实验手段,本论文主要进行自设计高真空实验方法的建立以及活性阴离子聚合方法学研究。首先建立了自设计高真空实验方法。自行设计了复杂实验装置的构建方法,在此基础上,改进了低沸点物料的高真空纯化处理装置,使丁二烯等低沸点、易气化物料的纯化处理、存贮以及使用更为便利。设计了高沸点物料的高真空纯化处理装置,有效地改进了热敏性高沸点物料(4-乙烯苯基二甲基硅烷、二苯基乙烯衍生物等)的高真空纯化处理。对反复应用于聚合装置中的清洗及反应部件进行了优化改进,提高了反应实施的安全性。进一步改进了双锂引发剂以及多级嵌段聚合物合成装置,并设计了新型定量化滴加反应装置。在装置改进以及设计基础上,进行活性阴离子聚合方法学研究。其次应用设计改进的双锂引发剂的合成装置,对高真空条件下的双锂引发剂的合成进行了优化改进。优化了双锂引发剂合成方法,在sec-BuLi过量0.5%条件下,一步反应得到双锂引发剂,舍去了溶剂替换步骤,改进后的合成方法极大地提高了双烯的利用率,所合成的双锂官能度F=1.98。以自合成双锂为引发剂、苯为溶剂、THF以及sec-BuOLi为调节剂体系下进行了丁二烯聚合研究,得到了微观结构以及分子量可控的窄分布聚丁二烯。建立了基于自设计高真空实验方法的双锂引发剂合成方法。再次应用自行设计的新型定量化滴加反应装置,进行了环状聚丁二烯的合成方法研究。以自合成双锂为引发剂,分别以二甲基苯乙烯基苯(MPEB)和双1,2-二甲基氯硅基乙烷(BDMCSE)为偶联剂,于定量化滴加反应装置中实施了高稀释浓度条件下的活性聚丁二烯环化反应。对环化反应机理进行了探讨,并在BDMCSE为偶联剂条件下成功合成了环状聚丁二烯。建立了基于自设计高真空实验方法的环状聚合物的合成方法,同时也为复杂拓扑结构聚合物合成方法学研究奠定了基础。最后应用自设计改进的多级嵌段聚合物合成装置,以自合成非极性溶剂可溶型双锂为引发剂,对4-乙烯苯基二甲基硅烷(VPDMS)进行了聚合探索研究,首次成功合成了三嵌段硅氢功能化F-SBS (PVPDMS-b-PBd-b-PVPDMS)热塑性弹性体。以自合成双锂为引发剂进行丁二烯聚合,再于自行设计的嵌段聚合反应装置中进行双端VPDMS嵌段聚合反应,合成了丁二烯以及VPDMS三嵌段共聚合物F-SBS。对前体聚丁二烯以及硅氢功能化F-SBS进行表征,所得聚合物分子量Mn为88kg/mol,分子量分布Mw/Mn为1.10,具有两个玻璃化转变温度,低温转变为-86℃,高温转变为85℃。结果充分表明所合成硅氢功能化F-SBS是一种新型的热塑性弹性体。该聚合物中含有的数量可控的硅氢反应性基团可进行硅氢加成反应,为进一步制备功能化聚合物奠定了基础,同时建立了自设计高真空实验方法下多级嵌段聚合物的合成方法。更多还原

【Abstract】 Living anionic polymerization is the most effective method to synthesize polymers with molecular weight, structure and molecular weight distribution under control. In recently years, the living anionic polymerization method is widely used for the synthesis of a series of novel polymers with complicated structures and broad application prospects. The corresponding experiments are strictly demanded free of oxygen and moisture for the high activity of carbanions. High vacuum technique, could make the reaction system closed and remove the impurities completely, is the essential experimental technique for the theoretical methodologic studies on living anionic polymerization. In this thesis, self designed high vacuum technique was constructed and corresponding anionic methodological researches were carried out.First, the self designed high vacuum technique was developed and constructed. Based on the long term practice, some key operation methods and apparatuses using in the operation of high vacuum technique were modified to make the reaction experiments safe and easy. A novel method that complicated apparatuses could be constructed by glass blowing of separated units of the apparatuses was developed and widely applied in living anionic polymerization reaction. The purification of agents with low boiling-point used for reactions, such as butadiene and epoxyethane, under high vacuum conditions was modified, which was more convenient and effective. The purification of agents with high boiling-point, such as 4-vinylphenyldimethylsilane (VPDMS) and the derivatives of DPE, was developed. The synthetic operation and apparatuses were modified, which made the reaction safe and effective. The apparatuses of synthesis of dilithium initiator and copolymers were modified and developed. A novel apparatus for quantified iterative titration reaction was developed. Based on theses modifications and design, anionic methodological researches were carried out.Second, the synthetic method of hydro-carbon soluble dilithium initiator was modified based on the self designed high vacuum technique. The dilithium initiator was synthesized by one step with the 0.5% excess of sec-BuLi, which made the reaction more facilitated and best use of MPEB. The functionality of dilithium initiator synthesized was 1.98. The polybutadienes with molecular weight and microstructure under control were obtained while the synthesized dilithium as initiator. Furthermore, the methodology of synthesis of hydro-carbon soluble dilithium initiator was constructed based on the self designed high vacuum technique.Third, the novel quantified iterative titration apparatus was used for synthesis of cyclic polybutadienes. The cyclic coupling reaction was done with synchronous titration under high dilution situations with synthesized dilithium initiator and MPEB and BDMCSE as coupling agents. The mechanism of cyclic reactions was investigated and the cyclic polybutadienes were obtained with BDMCSE as coupling agent. The methodology of synthesis of cyclic polymers was constructed based on the self designed high vacuum technique. Furthermore, the synthetic method is the base of studies on polymers with complicated topological structure.At the end, based on the self designed high vacuum technique, a novel functionalized thermoplastic elastomer F-SBS (PVPDMS-b-PBd-b-PVPDMS) copolymers were synthesized with the synthesized dilithium initiator at first time. After the living polybutadienes were obtained, the copolymerization was done in the apparatus for the synthesis of copolymers. A novel functionalized thermoplastic elastomer F-SBS with silyl-hydride groups was synthesized. The F-SBS block copolymers were characterized by1H-NMR, GPC and DSC and the structures were confirmed. The results showed that Mn was 88 kg/mol, Mw/Mn was 1.10, the glass transition temperatures were-86℃and 85℃, respectively. The silyl-hydride groups in polymers could prepare novel functionalized polymers by hydrosilylation reactions. Furthermore, the method of synthesis of multi-block copolymers was constructed base on the self designed high vacuum technique.更多还原