A novel method of MMA polymerization for GI-POFs

Rapid development of local area network (LAN) technology demands new media and the graded-index polymer optical fibers (GI-POFs) are considered to be a perfect one. The co-extrusion process would be a main approach to prepare GI-POFs whose primary stuff is poly-methyl methacrylate (PMMA). However the process to polymerize MMA for PMMA requires tens of hours currently. In this paper, the heat transfer in polymerization was analyzed and calculated, according to which the polymerization speed could be enhanced by removing part of the heat produced in the polymerization timely through a method of decompression of the reactant, which was validated by the experiments, also the optimum parameters of the reaction were obtained. Therefore the polymerization of the MMA could be completed within hours, and the polymer had a smaller polydispersity with a higher glass transition temperature. By means of decompression of the reaction mixture, not only could MMA be polymerized quickly and stably, but also its product properties would be improved.