Reconsideration on the mechanism of free-radical melt grafting of glycidyl methacrylate on polyolefin
- 作者：Jia-Lin Li ; Xu-Ming Xie ; xxm-dce@mail.tsinghua.edu.cn
- 关键词：GMA ; Melt grafting ; Depolymerization
- 刊名：Polymer
- 出版年：2012
- 期刊代码：83_00323861
- 类别：ms
- 出版时间：9 May, 2012
- 卷：53
- 期：11
- 页码：2197-2204
- 文件大小：855 K
摘要
The styrene (St) assisted melt grafting of glycidyl methacrylate (GMA) on polyolefin was carried out by Haake mixer, and the grafting mechanism was investigated and reconsidered. It was revealed that there is equilibrium of grafting of GMA and depolymerization of grafted PGMA chains in the GMA/polyolefin grafting process, which was affected by both of the temperature and GMA concentration. It was found that the depolymerization of PGMA grafted on polyolefin occurred at the temperature above ceiling temperature of PGMA and dominated the grafting process before the addition of styrene monomer, which induced the decrease in grafting ratio of GMA. Adding styrene as co-monomer could promote the equilibrium moving forward to form the St-GMA chains so that the grafting ratio was greatly improved. It is proved that either controlling the reacting temperature below the ceiling temperature or changing the feeding order of styrene and GMA is effective to attain high grafting ratio of GMA on polyolefin.