Poly(ethylene sulfide). I. Unique seed polymerization technique‐growth of “immortal” polymer

Poly(ethylene sulfide) was prepared by a unique two‐step polymerization technique in which a “seed polymer” was initially formed, compacted to a desired bulk density, and then used to polymerize fresh ethylene sulfide monomer. The seed polymer was prepared by reacting ethylene sulfide with diethylzinc‐water in a suitable solvent. The final polymer was an exact magnification that faithfully reproduced any shape of seed used with regard to relative dimensions, angularities, curvatures and even imperfections. Poly(ethylene sulfide) prepared by this process can be used for successive polymerizations that proceed at the same rate as the original seed with comparable zinc content, and thus behaves as an “immortal” polymer. The high molecular weight polymer melts above 200°C, is highly crystalline, and is, insoluble in most organic solvents at ordinary temperatures. A number of solvents dissolve the polymer above 140°C at which temperature thermal degradation takes place. When the polymer is stabilized by use of certain thermal stabilizers, it can be successfully molded to give excellent physical and mechanical properties.