聚异丁烯基热塑弹性体设计合成与性能  

Synthesis and Properties of Polyisobutylene-based Thermoplastic Elastomer

作　　者：张航天[1] 马婧伊 杨甜 张树[1] 吴一弦[1] Hang-tian Zhang;Jing-yi Ma;Tian Yang;Shu Zhang;Yi-xian Wu(State Key Laboratory of Chemical Resource Engineering,Beijing Laboratory of Biomedical Materials,Beijing University of Chemical Technology,Beijing 100029)

机构地区：[1]北京化工大学化工资源有效利用国家重点实验室生物医用材料北京实验室,北京100029

出　　处：《高分子学报》2022年第1期56-66,共11页Acta Polymerica Sinica

基　　金：国家自然科学基金(基金号51521062);中央高校基本科研业务费专项资金(基金号XK1802-2,XK1802-1)资助项目.

摘　　要：通过双端羟基聚异丁烯(HO-PIB-OH)与4,4'-二环己基甲烷二异氰酸酯(HMDI)及1,4-丁二醇(BDO)反应,设计合成一系列具有不同聚氨基甲酸丁二酯硬段长度的聚异丁烯基热塑弹性体(PIB-TPE),研究HMDI/PIB摩尔比值对PIB-TPE的聚集态结构、弹性回复、自修复性能、表面亲/疏水性、动态力学性能和拉伸性能的影响.结果表明:在PIB-TPE中,软段是完全饱和结构的PIB柔性链段,聚氨基甲酸丁二酯硬段通过氢键(无序氢键、有序氢键)形成结晶物理交联微区((3.6±0.5)nm),软段与硬段呈现明显的微相分离现象,常温下形成了三维超分子网络结构,高温下发生结晶熔融与氢键解离,超分子网络结构解散,形成黏流态,降低温度又可形成三维超分子网络结构;随着材料储存时间延长,无序氢键逐渐向有序氢键转变,有利于提高材料的拉伸强度和断裂伸长率.结晶熔融与氢键解离温度依赖于PIB-TPE中硬段长度,当HMDI/PIB摩尔比值小于19,硬段结晶熔融峰温度可达119℃以上,提高了PIB-TPE服役温度.PIB-TPE材料具有良好的弹性回复和自修复性能,且其膜表面的亲/疏水性可以通过HMDI/PIB摩尔比值或正己烷蒸汽常温下诱导表面自组装来调节,当HMDI/PIB摩尔比值从6增加至21,PIB-TPE膜表面的水接触角(WCA)由98.7°降低至77.8°,即由疏水性转变为亲水性.此外,PIB-TPE热塑弹性体中的完全饱和柔性PIB软段赋予其优良的减振阻尼性能,其损耗因子(tanδ)大于0.3的温域较宽(−55~25℃),且tanδ最大值(tanδ_(max))达到1.05.上述多嵌段聚异丁烯基热塑弹性体在生物医用、减振阻尼、自修复等功能材料领域具有潜在的应用前景.A series of polyisobutylene-based thermoplastic elastomers(PIB-TPE)with different polybutyl carbamate hard segments could be synthesized via reaction of hydroxyl-terminated PIB telechelics(HO-PIB-OH)with bis(4-isocyanatocyclohexyl)methane(HMDI)and then 1,4-butanediol(BDO).The influence of HMDI/PIB molar ratio on the aggregation structure,elastic recovery,self-healing property,hydrophilcity/hydrophobicity on the elastomer surface,dynamic mechanical and tensile properties of PIB-TPE were systematically investigated.The flexible PIB segments with fully saturated structure in PIB-TPE serve as soft segments.The physically crosslinked domains((3.6±0.5)nm)were generated due to the microphase separation between soft segments and hard segments and the crystallization from the ordered and disordered hydrogen bonds in polybutyl carbamate hard segments.The three-dimensional supramolecular network in PIB-TPE is formed at room temperature and dissociated to transform into viscous state due to melting of crystallization and dissociation of hydrogen bonds at high temperature and then gradually returned to the three-dimensional supramolecular network with decreasing temperature.The temperatures of melting of crystallization and dissociation of hydrogen bond depend on the length of hard segments in PIB-TPE.When the molar ratio of HMDI to PIB is less than 19,the temperature of melting peak of crystallization in hard segments is higher than 119℃.Some of the disordered hydrogen bonds in PIB-TPE could change into the ordered hydrogen bonds with storage time,leading to a great improvement in tensile strength and elongation at break of PIB-TPE materials.The PIB-TPE materials behave good elastic recovery and self-healing properties.The hydrophilcity/hydrophobicity on the PIB-TPE film surface could be adjusted by the molar ratio of HMDI to PIB or self-assembly induced by n-hexane vapor.The water contact angle(WCA)on surfaces of elastomer film decreased from 98.7°to 77.8°with an increase in the molar ratio of HMDI to PIB from 6 to 21,

关 键 词：聚异丁烯 热塑弹性体 氢键 超分子网络 熔融温度 亲/疏水性 

分 类 号：TQ334[化学工程—橡胶工业]