用ＤＳＣ及ＦＴＩＲ方法研究了聚四亚甲基醚型多嵌段聚氨酯（ＳＰＵ）与氯化聚氯乙烯（ＣＰＶＣ）共混物的相容性。结果表明，共混物具有两个分立的Ｔｇ，属不相容体系。ＦＴＩＲ结果表明随共混物中ＣＰＶＣ含量的增加，其ＳＰＵ组分的氢键键合的Ｃ＝Ｏ、Ｎ－Ｈ吸收峰所占的分数明显减少，ＣＰＶＣ与ＳＰＵ分子间存在较强的相互作用。多嵌段聚氨酯硬段含量的增加，加强了ＳＰＵ分子间的相互作用，同时也减小了共混物两组分的相容性。 The compatibility of polytetramethylene ether multiblock polyurethane (SPU) and chlorinated polyvinyl chloride (CPVC) blends was studied by DSC and FT-IR. The results show that the blend has two separate Tg, is an incompatible system. FT  IR results show that with the increase of the content of CPVC in the blend, the fraction of C = O and N-H absorption peaks of hydrogen bond in the SPU component decreases obviously, and there is a strong interaction. Multi-block polyurethane hard segment content increases, strengthening the SPU intermolecular interactions, but also reduces the compatibility of the two components of the blend.