Use of a cross-linked polystyrene/titanium tetrachloride tightly bound coordination complex as catalyst for the production of petroleum resins

Abstract

As a tightly bound coordination complex, divinylbenzene-cross-linked polystyrene/titanium tetrachloride (DVB-PS/TiCl₄) containing only Lewis acid sites was demonstrated to be an effective and water tolerant solid acid cationic initiator (catalyst) for the cationic polymerization of an industrial liquid pyrolysis gasoline feedstock containing a mixture of C₅/C₉ polymerizable hydrocarbons without the need for traditional catalyst residue removal. Special attention is paid to improving yields and the obtained resin properties and controlling resin properties by changing the feed. Compared with conventional homogeneous catalysts, this supported catalyst exhibits interesting differences due to its solid surface and pores, which enables a simpler process and reduces hazardous waste produced during conventional homogeneous methods. By using the supported catalyst, the major side reactions of chain transfer to the polymer with the formation of cross-linked and cyclic structures are efficiently suppressed. Moreover, we studied the stability of the active species on the support in a typical batch polymerization reaction and found particularly low levels of leaching.