三氯化铁对聚丙烯光氧化降解的作用

用红外及紫外光谱法研究了三氯化铁(FeCl₃)对聚丙烯(PP)光氧化降解的影响。实验结果表明,FeCl₃对聚丙烯光氧化有显著的促进作用,但促进作用与FcCl₃含量之间不成线性关系,存在一促进作用的极大值(在本实验条件下,FeCl₃含量为0.5%时,促进作用最大)。实验还表明,FeCl₃的作用可能包含了通过光解产生自由基引发PP光氧化反应、催化分解氢过氧化物以及光屏蔽等几种作用。根据FeCl₃的作用机理,解释了FeCl₃对PP光氧化降解的促进作用与其含量的依赖关系中存在的极位现象。

THE EFFECT OF FERRIC CHLORIDE ON PHOTOOXIDATIVE DEGRADATION OF POLYPROPYLENE

The influence of ferric chloride (FeCl₃) on photooxidative degradation of polypropylene (PP) has been studied by IR and UV spectrometric methods. Experimental results showed that FeCl₃ markedly accelerates photooxidation of PP, but the accelerating effect does not depend linearly on the contents of FeCl₃ in PP and there exists a maximum accelerating effect at a certain FeCl₃ content (Under our experimental conditions FeCl₃ shows the maximum accelerating effect when its content is 0.5%). It was also shown that the action of FeCl₃ possibly involves several mechanisms such as initiation of photooxidation of PP by free radicals produced in photolysis of FeCl₃, catalytic decomposition of hydroperoxide by FeCl₃, and light screening effect. On the basis of possible mechanisms of FeCl₃ action an explanation for the phenomenon of maximum accelerating effect of FeCl₃ was given.