聚氨酯的退火、淬火及共混体系的差谱表明,样品处于无定形态时,软段的羰基主要和硬段的NH 键之间形成氢键.结晶时,则在硬段中间形成更多的氢键.在共混体系中,随着聚氯乙烯含量增加,羰基和酰胺Ⅱ吸收峰都向低频位移.然而,聚氨酯仍然具有相当程度的有序. The difference spectrum of annealing, quenching and blending system of polyurethane shows that the carbonyl of the soft segment mainly forms hydrogen bond with NH bond of the hard segment when the sample is in the amorphous state, and more crystals are formed in the middle of the hard segment Hydrogen bond.In the blend system, the carbonyl and amide II peaks shift to lower frequencies as the polyvinyl chloride content increases.However, the polyurethanes still have a considerable degree of order.