【作者】 于美杰；

【导师】 鲁在君；

【作者基本信息】 山东大学 ， 化学工程（专业学位）， 2019， 硕士

【摘要】 侧羟基低聚物是以低聚物为主链,在其链中间引入羟基活性基团的聚合物,其数均分子量(Mn)小于10000。主链因其相对分子质量较低而具有独特的性能,引入羟基活性基团后,增加了低聚物的反应活性位点,使其应用领域更加广泛。本文通过阴离子聚合制备了低分子量的液体聚异戊二烯,并研究了其反应动力学。以此产物为原料,采用一锅法,与N-羟乙基马来酰亚胺发生Ene反应,合成了侧羟基液体聚异戊二烯,并将此作为多元醇合成了具有耐低温性的聚氨酯。然后利用RAFT聚合,制备了分子量较低的侧羟基异丁烯-马来酰亚胺交替共聚物。本论文的具体研究内容如下:1.在1 L的高压反应釜内,以环己烷作为反应溶剂,正丁基锂(n-BuLi)的引发条件下,进行了异戊二烯活性阴离子聚合的放大试验,合成了Mn为9000的液体聚异戊二烯。利用称重法研究了该聚合过程的反应动力学,得到了聚合温度以及异戊二烯单体的浓度这两个反应条件,对反应动力学产生的影响;求得了单体浓度对应的反应级数为1级;根据阿仑尼乌斯(Arrhenius)公式k=A*e^(-Ea/RT),得到反应的表观活化能Ea=84 KJ/mol。2.以N-羟乙基马来酰亚胺(NEMI)为原料,在氮气保护下,与液体聚异戊二烯发生Ene反应,制备了侧羟基液体聚异戊二烯,通过核磁(1H-NMR)、红外(FTIR)以及凝胶渗透色谱(GPC)进行表征,证明产物成功合成。研究了NEMI的加入量对产物中羟基含量的影响,结果表明,随着NEMI加入量的增加,产物中的羟基含量呈线性增加。进一步以侧羟基液体聚异戊二烯为原料,合成了聚氨酯弹性体,并利用动态力学热分析仪(DMA)和万能拉力机进行了测试。结果表明,以侧羟基液体聚异戊二烯为原料合成的聚氨酯的Tg为-40 ℃,具有良好的耐低温性,而且其软段羟基含量越高,聚氨酯的交联密度越大,从而使得拉伸强度也随之增大。3.采用可逆加成-断裂链转移(RAFT)聚合,以NEMI和异丁烯为原料,S-S’-二(α,α’二甲基,α"-乙酸)三硫代碳酸酯(BDAAT)为RAFT链转移剂,在100 ml的高压反应釜内,制备了低分子量的侧羟基异丁烯-马来酰亚胺交替共聚物。利用核磁(1H-NMR)和红外(FTIR)进行表征,证明产物被成功合成。研究了改变RAFT试剂的加入量对产物分子量产生的影响,并利用凝胶渗透色谱(GPC)进行表征;通过差示扫描量热分析仪(DSC)和热重分析仪(TGA)对产物进行了热学性能的测试。结果表明,产物的分子量随着RAFT试剂加入量的增多而逐渐减小;产物的Tg为135℃,Td5和Td10分别为335 ℃和372 ℃,表明聚合物具有耐热性和较好的热稳定性。更多还原

【Abstract】 The oligomers containing side hydroxyl groups is a polymer in which an oligomer is a main chain and a hydroxyl group is introduced in a segment thereof.Its number average molecular weight(Mn)is less than 10,000.The main chain has unique properties due to its relatively low molecular weight.The introduction of hydroxyl reactive groups increases the reactive sites of the oligomers,making it more widely used.In this paper,liquid polyisoprene with low molecular weight were prepared by living anionic polymerization,and its reaction kinetics was studied.The liquid polyisoprene was used as a raw material,and Ene reaction with N-hydroxyethyl maleimide was carried out to synthesize liquid polyisoprene containing side hydroxyl groups.A polyurethane elastomer having low temperature resistance was synthesized by using liquid polyisoprene containing side hydroxyl groupsas a polyol.Then,a isobutylene-maleimide alternate copolymer containing side hydroxyl groups with low molecular weight was prepared by reversible addition-fragmentation chain transfer polymerization.The primary content of the study and the results are shown as follows:1.Using n-BuLi as initiator and cyclohexane as solvent,a pilot-scale amplifica-tion test of isoprene was carried out by living anionic polymerization in a 1 L autoclave to synthesize relative molecules.A liquid polyisoprene having a mass of 9000.The reaction kinetics of the polymerization reaction was studied by weighing method.The influence of polymerization temperature and reaction monomer concentration on the reaction kinetics was studied.The reaction order corresponding to the monomer concentration is obtained as level 1.According to the Arrhenius formula k=A*e^(-Ea/RT),the apparent activation energy of the reaction is Ea=84 KJ/mol.2.N-hydroxyethylmaleimide(NEMI)was used as raw material to react with liquid polyisoprene under nitrogen to prepare liquid polyisoprene containing side hydroxyl groups.Characterization by nuclear magnetic resonance spectroscopy(1H-NMR),fourier transform infrared spectroscopy(FTIR)and gel permeation chromatography(GPC)confirmed the successful synthesis of the product.The effect of the amount of NEMI added on the hydroxyl content of the product was studied.The results show that the hydroxyl content of the product increases linearly with the increase of NEMI.The polyurethane elastomer was synthesized from liquid polyisoprene containing side hydroxyl groups and tested by dynamic mechanical thermal analyzer(DMA)and universal tensile machine.The results show that the Tg of polyurethane synthesized from side hydroxyl liquid polyisoprene is-40 ℃,which has good low temperature resistance,and higher content of soft hydroxyl group,the higher the crosslinking density and tensile strength of polyurethane.3.Synthetic method using reversible addition fragmentation chain transfer polymerization,using N-hydroxyethylmaleimide and isobutylene as raw materials,S,S’-Bis(α,α’-dimethyl-α"-acetic acid)-trithiocarbonate is a RAFT chain transfer agent,and a isobutylene-maleimide alternate copolymer containing side hydroxyl groups with low molecular weight is prepared in a 100ml autoclave.Nuclear magnetic resonance spectroscopy(1H-NMR)and fourier infrared spectroscopy(FTIR)was used to characterize the successful synthesis of the product.The effect on the molecular weight of the polymer was investigated by varying the amount of RAFT chain transfer agent added.Characterization was carried out by gel permeation chromatogr-aphy(GPC),and the products were tested for thermal properties using differential scanning calorimeter(DSC)and thermogravimetric analyzer(TGA).The results show that the more the RAFT chain transfer agent is added,the smaller the molecular weight of the product.The Tg of the product was 135 ℃,and Td5 and Td10 were 335 ℃ and 372 ℃,respectively,indicating that the polymer has high temperature resistance and good thermal stability.更多还原