摘要
用傅里叶变换红外光谱的透射光谱研究了溶液聚合的四种模型嵌段聚氨酯,在不同温度退火处理后,NH谱带、羰基谱带、醚键谱带等变化情况.从退火对羰基谱带的影响可看出,这些嵌段聚氨酯样品在200℃以下退火,可使氢键增强,而在200℃以上退火,则聚合物发生热降解.
These linear thermoplastic polyurethanes and polyureas are synthesized by a two-step solution polymerization method. Either a hydroxy-terminated polypropylene oxide(PPO-OH)of Mn = 2040, or an amine-terminated polypropylene oxide(PPO-NH2) of Mn = 2100 is used as the soft segment to produce the urethane or urea linkages respectively at the ends of the polyether backbones. Pure 4, 4'-diphenylmethane diisocyanate(MDI) is extended with either 1,4-butane diol(BDO) to form the urethane hard segments or with 1,4-butane diamine(BAD) to form the urea hard segments. Four different combinations of polyurethane-urethane(MDI/PPO-OH/BDO),polyurea-urethane(MDI/ PPO-NH2/BDO) ,polyurethane-urea(MDI/PPO-OH/BDA) ,polyurea-urea(MDI/PPO-WH2/BDA) are obtained. The effect of thermal annealing on NH region,carbonyl region,ether region has been studied by transmission spectra of Fourie transform infrared spectroscopy(FTIR). Annealing below 200°C improves hydrogen bonding in both urea and urethane linkages within the hard segment domains as evidenced from the increase in the hydrogen-bonded carbonyl absorbance. When materials are annealed above 200°C.thermal degradation and other side reactions can readily occur.
出处
《烟台大学学报（自然科学与工程版）》
CAS
1992年第4期38-45,共8页
Journal of Yantai University(Natural Science and Engineering Edition)
关键词
聚氨酯
聚脲
热处理
红外光谱
退火
Polyurethane. Polyurea. Fourie transform infrared spectroscopy(FTIR). Annealing.
