| Abstract: | A new method for the production of polydimethylbenzylenes,$ \rlap{--} {\rm C}_6 {\rm H}_4 ({\rm CH})_2 {\rm CH}_{\rm 2} \rlap{--} ]_n $ , involves the polycondensation of the mono- and dichloromethyl and mono- and diacetoxymethyl derivatives of p-xylene via an acid-catalyzed reaction in anhydrous acetic acid. The reaction of the difunctional derivatives is slower than the reaction of the monofunctional ones, leading to linear, predominantly crystalline, high-melting polymers with molecular weights of 2000–3000. Polycondensation of both monomers under different feed ratios leads to polymers with the same structure, and the monofunctional monomers condense with themselves more favorably than with the difunctional ones. Thus a head-to-head structure is preferred, and crystalline polymers of high structural purity are obtained. |
