Abstract: Coatings having very low critical surface tensions comprise (1) a hydrophilic polymer such as polyacrylamide, (2) an ionic perfluorocarbon compound such as 3-[((heptadecafluorooctyl)sulfonyl)amino]-N,N,N-trimethyl-1-propanaminium iodide and (3) a cyclic sulfonium zwitterion cross-linking agent such as 2,2-bis(3-tetrahydrothiophenium-4-oxidophenyl)-propylidene. Such coatings are most advantageously employed as release coatings on internal surfaces of chemical reaction vessels in order to minimize the deposition (build-up) of undesirable materials on such internal surfaces.

Abstract: Polymerization of ethylene by free-radical initiation at high temperature and pressure in a stirred autoclave by continuous process is improved by means of cooling at inner wall in contact with polymerization reaction mixture and removing part of the exothermic heat of polymerization reaction by indirect heat transfer to heat exchange fluid.