高性能液体端羧基氟橡胶的氟化加成反应合成  

Synthesis of High Performance Carboxyl-terminated Liquid Fluoroelastomers Based on Fluorination Addition Reaction

作　　者：姜帆 李琬桐 赵树发 石宁 张梦霞 方庆红 李东翰 JIANG Fan;LI Wantong;ZHAO Shufa;SHI Ning;ZHANG Mengxia;FANG Qinghong;LI Donghan(College of Materials Science and Engineering,Shenyang University of Chemical Technology,Shenyang 110142,China;Liaoning Provincial Key Laboratory of Rubber&Elastomer,Shenyang University of Chemical Technology,Shenyang 110142,China;Shenyang Guide Rubber Products Co.Ltd.,Shenyang 110141,China)

机构地区：[1]沈阳化工大学材料科学与工程学院,沈阳110142 [2]辽宁省橡胶弹性体重点实验室,沈阳110142 [3]沈阳盖德橡胶制品有限公司,沈阳110142

出　　处：《材料研究学报》2025年第1期11-20,共10页Chinese Journal of Materials Research

基　　金：国家自然科学基金青年基金(52003165);辽宁省青年人才扶持计划(XLYC2203101);辽宁省教育厅基金(LJKMZ20220769);辽宁省自然科学基金(2023-MSLH272);沈阳市中青年科技创新人才计划(RC210195);沈阳化工大学-国家科学基金优秀青年学者培养项目(2022YQ001)。

摘　　要：基于固体氟橡胶分子链中偏氟乙烯结构的化学属性,用“一锅法”氧化降解/氟化加成协同反应合成了液体端羧基氟橡胶(SCTLF)。构建了以1-氯甲基-4-氟-1,4-二氮二环[2,2,2]辛烷双四氟硼酸盐(Selectflour)为氟化试剂、四丁基氟化铵(TBAF)为亲核试剂、N-溴代丁二酰亚胺(NBS)为亲电试剂的氟化加成反应体系,在消除含氟双键(C=C)的同时,使产物的氟含量和热稳定性提高,实现了高性能化。使用红外光谱(FTIR)、氢谱核磁(^(1)H-NMR)、氟谱核磁(^(19)F-NMR)表征其分子链结构,用凝胶渗透色谱(GPC)和化学滴定分别测试其分子量和端基含量。结果表明,氟化加成反应后合成的SCTLF,其数均分子量为2410,羧基含量为2.30%,C=C含量由0.30 mmol/g降低至0.08 mmol/g,符合Zaitsev序列结构规则的含氟C=C活性较高且加成反应完全,符合Hofmann序列结构规则的含氟C=C有部分残留,其氟含量达到65.47%。SCTLF的玻璃化转变温度(T_(g))为-34℃,初始热分解温度(T_(d))显著提高到270℃,在20℃其动力粘度为46 Pa·s。HDI三聚体可以实现SCTLF的固化,其产物具有优异的力学性能和化学稳定性。A high-performance carboxyl-terminated liquid fuoroelastomers(SCTLF)was synthesized by a one-pot oxidative degradation/fluorination addition synergistic reaction for the first time,with 1-chloromethyl-4-fluoro-1,4-diazoniabicyclo[2,2,2]℃ tane bis(tetrafluoroborate)(Selectflour)as fluorination reagent,tetrabutylammonium fluoride(TBAF)as nucleophilic reagent,and N-bromosuccinimide(NBS)as electrophilic reagent.This reaction system can simultaneously eliminate the fluorinated double bonds(C=C),increase the fluorine content,enhance their thermal stability,and thereby achieve high performance of the products.The molecular chain structure of the synthesized SCTLF was characterized by using Fouriertransform infrared spectroscopy(FTIR),proton nuclear magnetic resonance(^(1)H-NMR),and fluorine nuclear magnetic resonance(^(19)F-NMR).Besides,its molecular weight and terminal group content was determined by means of gel permeation chromatography(GPC)and chemical titration method.After the fluorination addition reaction,SCTLF had average molecular weight of 2410,carboxyl content of 2.30%,and C=C content decreased from 0.30 mmol/g to 0.08 mmol/g.The fluorinated C=C conforming to Zaitsev's rule showed high reactivity and complete reaction,while those conforming to Hofmann's rule had some residuals,with a calculated fluorine content of 65.47%.The glass transition temperature(T_(g))of SCTLF was -34℃,and its initial thermal decomposition temperature(T_(d))significantly increased to 270℃.At 20℃,its dynamic viscosity was 46 Pa·s.The curing of SCTLF with HDI trimer resulted in a cured product with excellent mechanical properties and chemical stability.

关 键 词：有机高分子材料 氟化加成反应 液体氟橡胶 一锅法 

分 类 号：TQ333.93[化学工程—橡胶工业]