3-(2-氰基乙氧基)甲基-和3-[甲氧基(三乙氧基)]甲基-3′-甲基氧杂环丁烷的合成及其共聚体研究

Studies on Synthesis of 3-(2-Cyano ethoxy)methyl- and 3-[triethylenoxy)]methyl-3′-methyloxetane and Their Copolymers

以三羟甲基乙烷为原料, 通过脱水反应首先制得3-羟甲基-3'-甲基氧杂环丁烷(HMO). HMO再分别与丙烯腈和二缩三乙二醇单甲醚反应得到两个取代氧杂环丁烷单体3-(2-氰基乙氧基)甲基-和3-[甲氧基(三乙氧基)]甲基-3'-甲基氧杂环丁烷(HMOAN和HMOPEO). 再用阳离子开环聚合方法, 以BF 3\5乙醚作催化剂, 丁二醇为引发剂, 将两类单体共聚即可得到一系列不同组成的共聚物(PAP). 利用 1H NMR谱图计算了该共聚物中两种不同结构单元的比, 结果表明, 其与投料比基本吻合. GPC测得该共聚物的数均分子量范围为2 756～5 342, 分子量分布为1.26～1.83. DSC测试结果发现, 除在225～246 K之间有一个玻璃化转变温度之外, 在305～348 K之间还存在一个热转变温度. TGA测得共聚物的分解温度为573 K, 远高于目前广泛使用的液体电解质. 电导率测试结果表明, AN20的室温电导率可达到1.07×10 -5 S/cm, 353 K时电导率可达到2.79×10 -4 S/cm, 接近实用要求.

The two monomers 3-（2-eyano ethoxy）methyl- and 3-[ （methoxy-triethyleneoxy）]-methyl-3＇- methyloxetane were prepared from the reaction of 3-methyl-3 ＇-hydroxylmethyl oxetane（HMO） with aerylonitrile and triethylene glycol monomethyl ether, respectively. A novel series of eopolymers were synthesized by starting from these two monomers along with BF3 · ether as the catalyst and BDO as the initiator via a cationic ringopening eopolymerization. The GPC analysis presents the number average molecular weight of the copolymers ranging from 2 756 to 5 342, and polydispersity from 1.26 to 1.83. Regarding the glass transition temperature （ Tg） , the DSC results imply that these eopolymers would have a higher ion induetivity than pure PEO. And the TGA measurements reveal that the eopolymers possess a very high heat decomposition temperature. The conductivity of the AN20 at room temperature is about 1.07 × 10^-5 S/cm, while at 353 K is 2.79 × 10^-4 S/cm, approaching the practical requirement of polymer electrolytes for lithium ion batteries.