New selective catalytic systems for linear polydicyclopentadiene synthesis

Linear polydicyclopentadiene (l-PDCPD) was synthesized using W-based combin ations and silicon organic derivatives. Kinetic studies were carried out by solution polymerization of the monomer hi glass vials. Because WCl6 is a s trong Lewis acid which induces a cationic crosslinking of the linear polyme r, it was replaced by WOCl4, less electrophile. Thus, the crosslinking tend ency was fully eliminated. WOCl4 formation "in situ", from WCl6 and wet tol uene, is very important from the practical point of view, the rigours of Zi egler-Natta catalysis being eliminated. Dicyclopentadiene polymerization is a step-by-step reaction, the concentration of the active centers during th e process being constant.