Stabilized ethylene sulfide polymer composition and process for stabilizing moldable ethylene sulfide polymer

摘要

A heat-stabilizer for ethylene sulphide polymers and copolymers comprises at least one nitrogen-containing compound having a boiling point in excess of the melting point of the polymer. Suitable stabilizers include amides, amines, hydroxyl- and other substituted amines, polyamines, modified polyamines, N-heterocyclic compounds, polyamides, polyalkyleneimines, adducts of epoxides with amines and alkyleneimines, polyureas and phosphorus containing nitrogen compounds; many examples are given. Suitable quantities of stabilizer are 0.05 to 5% by weight of polymer. Specified monomers for copolymerizing with ethylene sulphide are other episulphides, unsaturated thioglycidyl compounds, olefines, dienes, vinyls, epoxides and alkylene imines; many are specified. Specified polymerization catalysts comprise (a) organo metallic compounds R2M, wherein R is alkyl or aryl and M is Zn, Cd or Hg, and (b) water, hydrogen sulphide, alkylamines, alkanols, mercaptoethanol, acetone, lower fatty acids, aldehydes, oxygen, sulphur, carbonyl sulphide and carbon disulphide. A seed catalyst is prepared by polymerizing episulphide monomer in solution with the catalyst mixture and compressing the product which is used to polymerize episulphides to granules. Other catalysts are cadmium, zinc and mercury compounds, carbonates and oxides of various metals, Friedel-Craft catalysts, peroxides, ionizing radiation, sodium naphthenate, sodium cyanide, metal alkyls and sodium. Suitable additives to the stabilized polymer and pigments, antioxidants, U.V. stabilizers, fillers, flame retardent agents, nucleating agents and lubricants. The Examples describe the polymerization of ethylene sulphide using (1) diethyl zinc and water, and (27) a seed catalyst; the resulting polymers are stabilized.