Nano-reactors for controlling the selectivity of the free radical grafting of maleic anhydride onto polypropylene in the melt
writer：Dean Shi*, R. K. Y. Li, Yutian Zhu, Zhuo Ke, Jinghua Yin, Wei Jiang, Guo-Hua Hu*
keywords：Nano-Reactors;Free Radical Grafting;Polypropylene;Maleic Anhydride
source：期刊
Issue time：2006年
This paper reports on a successful application of the concept of nanoreactors to effectively controlling the selectivity of the free radical grafting of maleic anhydride (MAH) onto polypropylene (PP) in the melt, an industrially relevant process. More specifically, a free radical initiator of type ROOR was first confined into (or encapsulated by) the galleries of an organically modified montmorillonite (o-MMT) whose interdistance was 2.4 nm. Primary free radicals (RO ·) formed inside the o-MMT galleries had to diffuse out before they could react with the PP backbone. The controlled release of the primary free radicals significantly increased the grafting degree of MAH onto PP and greatly reduced the level of the chain scission of the latter. Those results were better understood by electron spin resonance studies on model systems and by Monte Carlo simulations.