【作者】 王婷婷；

【导师】 谢美然；

【作者基本信息】 华东师范大学 ， 高分子化学与物理， 2023， 硕士

【摘要】 聚碳酸酯（PC）的合成原料之一为双酚A（BPA）,它具有毒性和雌性激素效应且来源于不可再生的石油,因而对人类健康及资源消耗造成不良影响。目前使用来源于生物质的异山梨醇（IS）替代BPA与碳酸二苯酯（DPC）,生成的生物基异山梨醇型聚碳酸酯（PIC）,因其优异的机械强度、光学特性和耐磨耐热性,被认为是最有可能替代传统PC的产品。为了达到PC工业化应用的级别,PIC的分子量必须足够高,生产工艺简单且成本低。由于PIC结构中IS单元的刚性,PIC的熔体粘度过大,不容易加工成型而应用领域窄。因此,对PIC的改性扩大其应用范围变得十分必要。本研究发现商品化试剂是制备高分子量PIC的高效催化剂,具有工业化应用的前景。聚醚型共聚聚碳酸酯富含醚氧基团,可用作聚合物电解质。具体内容如下:首先,选择4种锂盐催化剂,催化IS与DPC的熔融缩聚。对比催化剂的不同阴离子对合成PIC的催化效率,发现乳酸锂（Li LAc）的催化效率最高。通过不同熔融缩聚反应条件的对比,筛选出最佳的聚合条件,仅1.5 h可以制备出重均分子量（M_w）为105.0 k Da的PIC。PIC薄膜的透光率可达90%,拉伸强度达42.5 MPa。通过核磁共振、中间体捕获和DFT模拟计算,分析催化剂对反应底物的作用机理和反应中间体的结构,发现IS与Li LAc间氢键的形成以及催化剂间的静电协同作用,是Li LAc能够高效催化合成PIC的关键因素。其次,选择5种富含醚氧基团的脂肪族二醇作为共聚单体,控制单体的比例合成共聚型生物基脂肪族聚碳酸酯（PAIC）。引入线形共聚单元比环形结构的PAIC具有更好的柔韧性,IS含量的减少有利于PAICs的分子量提高,同时可实现共聚型聚碳酸酯的玻璃化转变温度（T_g）可控。引入四甘醇（TTEG）进行共聚得到的聚醚型聚碳酸酯（PTTIC）,PTTIC的T_g降低和添加锂盐（Li TFSI）,导电性能明显提高,PTTIC中添加30 mol%的Li TFSI在室温下导电率可达1.0×10^-3 S·cm^-1,可满足聚合物电解质的实用性要求。更多还原

【Abstract】 Bisphenol A（BPA）is one of the synthetic materials of polycarbonate（PC）,while it has toxicity and estrogen effects and comes from non-renewable petroleum,thus causing great adverse effects on human health and the environment of earth.At present,biomass isosorbide（IS）was used to replace BPA,and synthesize biobased poly（isosorbide carbonate）（PIC）with diphenyl carbonate（DPC）.PIC was considered as the most likely alternative to traditional PC because of its excellent mechanical strength,optical characteristics,and resistance to wear and heat.In order to reach the level of PC industrial application,the molecular weight of PIC must be high enough and the production process must be simple and low cost.Due to the rigidity of IS in PIC structure unit and the high viscosity of PIC melt,it is not easy to process finished products and the application field is limited.Therefore,it is necessary to modify PIC to expand its application range.In view of the above deficiencies,it was found that the high efficiency catalyst can be used to prepare high molecular weight PIC in this paper and industrial grade PIC production,and polyether-type polycarbonate was prepared as polymer electrolyte by using ether-oxygen group in IS and other diols.The main contents were as follows.In second chapter,we designed four lithium salt catalysts and compared the effects of catalysts with different anionic on the efficiency of PIC synthesized by melting polycondensation of IS and DPC.It was found that lithium lactate（Li LAc）as catalyst had the best catalytic efficiency.The optimal polymerization conditions were selected by comparing different melting and polycondensation reaction conditions,PIC with M_w of105.0 k Da can be prepared for 1.5 h,the transmittance of PIC film is 90%and the tensile strength is 42.5 MPa.Finally,the mechanism of the catalyst on the substrate and the structure of the intermediate were analyzed by means of nuclear magnetic resonance,intermediate capture and DFT simulation.It was found that the synergistic effect of hydrogen bond formation between IS and Li LAc,as well as the electrostatic interaction between catalysts,enables Li LAc to efficiently catalyze PIC synthesis.In the third chapter,we designed 5 kinds of aliphatic monomers and controlled the proportion of the monomers to synthesize different poly（aliphatic isosorbide carbonate）s（PAICs）.It was found that the straight chain copolymerization unit had better flexibility than the ring structure.The reduction of IS content was beneficial to the increase of molecular weight of PAICs,and the T_g control of copolymerized polycarbonate could be realized.Introducing tetraethylene glycol（TTEG）for copolymerization to obtain polyether polycarbonate（PTTIC）,reducing the T_g of PTTIC and adding Li TFSI can significantly improve the conductivity.The conductivity of Li TFSI with 30 mol%in PTTIC is up to 1.0×10^-3 S·cm^-1 at room temperature,which can be used as a polyelectrolyte.更多还原