CAJ | 학술논문

采用两步合成法,以4,4'-二苯基甲烷二异氰酸酯(MDI)和1,4-丁二醇(BDO)为硬段,相对分子质量分别为1000、2000、4000的聚氧化丙烯二元醇(PPG)为软段,制备了一系列聚醚型聚氨酯(PUR)弹性体,研究了预聚体异氰酸酯指数R及软段相对分子质量对PuR动态力学性能的影响.结果表明,预聚体R值增大,即PUR的硬段含量增加,储能模量G'提高,软段相的玻璃化转变温度(T_g)升高,软硬相区的相容性增大;软段相对分子质量增加,PuR的G'下降,软段相的T_g降低,并出现硬段相的玻璃化转变,软硬相区的相分离程度增大.
채용량보합성법,이4,4'-이분기갑완이이청산지(MDI)화1,4-정이순(BDO)위경단,상대분자질량분별위1000、2000、4000적취양화병희이원순(PPG)위연단,제비료일계렬취미형취안지(PUR)탄성체,연구료예취체이청산지지수R급연단상대분자질량대PuR동태역학성능적영향.결과표명,예취체R치증대,즉PUR적경단함량증가,저능모량G'제고,연단상적파리화전변온도(T_g)승고,연경상구적상용성증대;연단상대분자질량증가,PuR적G'하강,연단상적T_g강저,병출현경단상적파리화전변,연경상구적상분리정도증대.
A series of polyether-based polyurethane ( PUR) elastomers were prepared from 4,4'-diphenylmethanediisocyanate (MDI) and 1,4-butanediol (BDO) as hard segments and polypropylene oxideglycol (PPG) with different relative molecular mass (1000, 2000, 4000) as soft segments by two-step process. The effects of the isocyanate index R of the prepolymer and the relative molecular mass of soft segment on the dynamic mechanical properties of PUR were studied. The results indicated that with the increase of R, the content of hard segments raised, which resulted in notable increases in storage modulus G', glass transition temperature (T_g) of soft segments and compatibility between soft and hard phase domain ; while the increase of relative molecular mass of soft segments led to decrease in G' and T_g of soft segments. In the meantime, the appearance of T_g of hard segments implied high level microphase separation.