^(13)C核磁共振研究氯化无规聚丙烯的结构

CARBON-13 NMR STUDY OF CHLORINATED ATACTIC POLYPROPYLENE

用核磁共振方法(^(13)C-NMR)研究了一系列氯化无规聚丙烯的结构。在0—52.84％(wt)的氯化度范围内,主要为单氯取代,二氯取代很少。伯、仲、叔三种氢的相对氯化活性为R(CH)>R(CH_2)>R(CH_3),并乒表明氯化反应比较均匀地发生在无规聚丙烯分子链上。影响聚丙烯氯化反应的结构因素主要为C—H键的离解能,大分子自由基稳定性和大分子链构型等。

Carbon-13 Nuclear Magnetic Resonance (NMR) technique is used to study the microst-ructure of a series of chlorinated atactic polypropylene. Results show that the chlorination occure mainly in the way of mono-substitution up to a chlorine content of 52.84% by weight. The mean relative reactivity of three kinds of protons towards chlorination is R(CH)>R (CH2) >R(CH3), and the chlorine atoms are distributed homogeneously in the molecular chain. It is shown that the chlorination of polypropylene could be influenced by three structure factors: C-H bond energy, stability of the macromolecular free radical and configuration of the molecular chain.