摘要
聚氨酯弹性体(PU)的软段类型和分子量是影响其低温性能的主要因素,硬段浓度亦有一定影响。软段分子量相同时,聚酯型PU的软段玻璃化温度比聚醚型的高30℃。软段类型相同时,软段分子量越高,其玻璃化温度越低。硬段浓度只对软段分子量为1000的聚酯型PU的低温性能有影响,并随硬段浓度的增加而降低;而对软段分子量为2000的聚酯型和聚醚型PU的低温性能几乎没影响。硬段浓度主要影响橡胶台区模量和耐热性能,且台区模量随硬段浓度的增加而提高。氢键能使台区模量承受高温,在200℃时PU中的氢键仍能保留35％—40％。
The relationship between the structure of segmented polyurethane (PU) elastomers and their properties was reviewed with 10 references . The types of soft segments and molecular weight of PU were the major factors which influenced the low temperature properties of PU elastomers . When the molecular weights of soft segment were the same , the glass transition temperature of polyester PU was 30 °C higher than that of the polyether PU . When the types of soft segments were the same , the glass transition temperature decreased with the increase of molecular weight . The hard segments only affected on the low temperature of the PU with soft segment molecular weight 1000 , but did not affected on those molecular weight 2000 . The hard segment content affected mainly on the plateau modulus and thermal proper ties of PU ,and the plateau modulus increased with the increase of hard segment content . The hydrogen bond could made PU withstand higher temperature , the hydrogen bond in PU remained 35%- 40% at 200°C .
出处
《合成橡胶工业》
CAS
CSCD
北大核心
1991年第4期294-297,共4页
China Synthetic Rubber Industry
关键词
聚氨酯
弹性体
结构
性能
polyurethane elastomer
relation between structure and properties
dynamic properties
molecular weight
glass transition temperature
review
