On the polymerization of polyfunctional compounds

Abstract

AbstractThe present investigation is a two‐sided approach to polyfunctional compounds, namely: (1) polymerization of unsaturated monomers containing reactive groups, in particular, methylol derivatives of unsaturated acids; (2) cyclopolymerization of diolefinic monomers. In the first method of attack conditions have been investigated under which soluble, linear polymers are formed. Our studies have thrown light on the mechanism of reactions facilitating the formation of crosslinks. From a study of the polymerization of methylolacrylamide monomers (in collaboration with L. M. Novichkova) it became possible to direct the reaction towards the formation of soluble, linear polymers. The possibility of further conversions such as transformation of the linear polymers to three‐dimensional ones leads to the polymerization‐condensation concept of polymer formation. This is of particular interest, since it provides the basis for predetermined modification of polymer properties (for example, elimination of flow, increase of strength, chemical resistance, etc.). The reactivity of the methylolamide group allows the use of the compounds in question for these purposes, for instance as copolymer with acrylonitrile. The second method of attack is the cyclic polymerization of symmetrical and unsymmetrical diolefine monomers and of compounds arising in the process of polymerization of 1–6 unsaturated systems. Earlier, Butler, Marvel, Jones and others pointed out the formation of linear cyclic polymers in the polymerization of symmetric divinyl and diallyl monomers unsaturated in the 1,5‐ and 1,6‐positions. The authors of the present work have synthesized a number of acetals of vinyl alcohol and ascertained the conditions for the formation of linear polymers consisting of six‐membered cyclic repeating units connected by methylene groups. Polymerization of asymmetric diene monomers was investigated using as examples vinyl crotonate, bulk polymerization of equimolecular quantities of allyl alcohol and maleic anhydride, and copolymerization of maleic anhydride with dibenzalactone. The establishment of the possibility of divinylacetal polymerization according to a cyclic mechanism makes it possible to outline new ways of synthesis of the acetals of polyvinyl alcohol. It has also been found that in the polymerization of the asymmetric diene monomers vinylcrotonate and monoallyl maleate, soluble, linear polymers are formed, of which the properties indicate that cyclization takes place in the course of the reaction.