4-氨基脲嘧啶与溴化丁基橡胶反应制备热可逆交联丁基橡胶  

Preparation of thermoreversible crosslinking butyl rubber by reaction of brominated butyl rubber with 4-amino-uracil

作　　者：柏华荣[1] 程斌[1] 

机构地区：[1]北京化工大学北京市新型高分子材料制备与加工重点实验室,北京100029

出　　处：《合成橡胶工业》2008年第3期195-199,共5页China Synthetic Rubber Industry

摘　　要：在相转移催化剂作用下,用4-氨基脲嘧啶与溴化丁基橡胶(BBR)反应制备了热可逆交联丁基橡胶(IIR),考察了取代反应的影响因素,并研究了含有4-氨基脲嘧啶基团的IIR的结构与拉伸性能。结果表明,4-氨基脲嘧啶取代了BBR中的溴原子,且伯溴代烯丙基结构中的溴原子被完全取代,仲溴代烯丙基结构中的溴原子大部分被取代;IIR上的4-氨基脲嘧啶基团可通过氢键自组装形成热可逆网络结构;在4-氨基脲嘧啶用量为0.010 mol、相转移催化剂四丁基溴化胺/4-氨基脲嘧啶(摩尔比)为1∶1、氢氧化钾水溶液/甲苯溶液(体积比)为50∶80、反应温度为80℃、反应时间为4 h的条件下,4-氨基脲嘧啶与BBR反应后溴原子取代率最大值可达到77%;含有4-氨基脲嘧啶基团的IIR的拉伸强度较BBR增大了2倍,具有热塑性弹性体特征。The thermoreversible crosslinking butyl rubber（IIR） was prepared by reaction of brominated butyl rubber with 4-amino-uracil in the presence of the phase transfer catalyst. The influential factors on the substitution reaction were investigated. The structure and tensile properties of IIR contained 4-amino-uracil were studied. The results showed that exo allylic Br was completely substituted by 4-aminouracil, while endo-allylic Br was partially done. The thermoreversible network structure was formed by self-assembly of hydrogen bond on the 4-amino-uracil group. When 4-amino-uracil was 0. 010 mol, mole ratio of TBAB/4-aminouracil was 1/1 and volume ratio of KOH liquor/toluene was 50/80, the substituting rate of bromine could reach 77% at 80 ℃ for 4 h. The tensile strength of IIR with 4-amino-uracil tripled to that of BBR, and the rubber behaved like a thermoplastic.

关 键 词：溴化丁基橡胶 4-氨基脲嘧啶 热可逆交联 丁基橡胶 拉伸性能 

分 类 号：TQ333.6[化学工程—橡胶工业]