Friedel-crafts and related reactions on poly(vinyl chloride)

Polyvinyl chloride solubilized in an appropriate solvent can be transformed to a complex mixture of chemical compounds by treating it with aromatics in the presence of Friedel‐Crafts catalysts. The primary reaction is the alkylation of aromatics with polyvinyl chloride; it is followed by other parallel and secondary reactions, viz., intramolecular cyclizations of alkylated products and a cleavage of molecules to fragments of lower molecular weight. All this is accompanied by the process of hydrogen chloride elimination from the reacting polymer. The chlorinated hydrocarbons, when used as solvents can also take part in reactions, leading to the crosslinking of polymers. An earlier work of Belgian authors (Teyssié, Smets) was continued in order to elucidate further the complex of the reactions mentioned above. A number of Friedel‐Crafts condensations were carried out using polyvinyl chloride to alkylate benzene and toluene in various solvents, such as 1,2‐dichloroethane, cyclohexanone, trichloroethane and tetrahydrofurane in the presence of AlCl3 and BF3 as catalysts. The kinetic curves representing the dehydrochlorination process were obtained, allowing the interpretations of the mechanisms involved. The products thus obtained were characterized by physical and chemical means. The significant peaks in IR‐spectra which would account for the intramolecular cyclizations and branching of macromolecular chains were also observed.