Radically induced hydrosilylation of polypropylene through reactive extrusion

Hydrosilylation of terminal double bonds in polypropylene was investigation via free radical process in the melt phase. This process involved the following two reactions occurring in parallel: chain scission which lead to formation of double bonds and the addition of silyl radicals to such bonds. Fourier Transform Infrared Spectrometry (FTIR) was used to follow silane incorporation and terminal double bond formation. Using a single crew extruder and a model silane compound, a 23 full factorial experimental design was implemented with the following investigated factors: residence time, silane concentration and peroxide concentration. Statistical analysis of the FTIR results showed the significance of the factor and interaction effects. The experimental results have shown that melt-phase hydrosilylation of polypropylene can be accomplished through this non-catalytic, free radical method.