Patent GB-695112-A (GB)
Title: Improvements in or relating to crystalline and oriented polymers and copolymers
IPC: C08F236/16
Filed: 1949-12-09
Abstract: In a modification of the process of the parent Specification for producing polymers and co-polymers of 2,3-dichlorobutadiene-1,3 of enhanced crystalline tendencies the compounds to be deformed have intrinsic viscosities of from 0.1 to 1.5, with preferably a crystalline M.P. of 130-210 DEG  C., the copolymers contain at least 90 per cent of 2,3-dichlorobutadiene-1,3 and the restrained chlorination after-treatment is confined to 3-5 per cent chlorine based on the weight of the polymer.  Suitable resins are obtained by the use of modifiers such as methyl, ethyl, propyl, isopropyl, t-butyl, amyl, octyl, t-octyl, 2-ethyl hexyl, n- and t-dodecyl, hexadecyl, lauryl, cetyl, eicoxyl and cyclohexyl mercaptans, tetra- and decamethylene dimercaptans, 3-thiophenethiol, thiophenol, thio a - and b -napthols, thiocresols, thioxylenols, benzyl and 2-phenyl ethyl mercaptans, thioabietinol, a -pinene, hydrogenated and disproportionated thioabietinol, and terpenyl mercaptans, thiosalicylic, thiolacetic, and thioglycolic acids, ether and thioether mercaptans prepared by reacting propylene and other alkylene 1,2-disulphides with water or alcohols, and diisopropyl xanthogen disulphides in (1) mass polymerization methods, with up to 5 per cent catalyst, (2) solution methods, e.g. in toluene, benzene, methanol, a -hydroxyethyl ether, (3) aqueous suspension or emulsion methods in the presence of sodium or potassium laurate, myristate, oleate, palmitate and stearate, or sodium sulphates of lauryl, myristyl, oleyl, palmityl, stearyl alcohols, hydrogenated coconut oil fatty alcohols, sodium sulphonated petroleum fractions or Fischer-Tropsch products, sodium (2-ethyl hexyl) sulphosuccinate, fatty acid monoesters of hexitans or didodecyl naphthalene sulphonate.  The reactions may be performed in a closed vessel from which oxygen is excluded at from -30 DEG  to 70 DEG  C. with catalysts, e.g. hydrogen, benzoyl, acetyl, and di-tertiary peroxides, and sodium, potassium or ammonium persulphates or perborates.  An anti-freeze compound, e.g. methanol, is added at low temperatures. The reaction may be arrested with phenyl-b -naphthylamine and the product precipitated with methanol and where copolymers are prepared the dichlorobenzene may be added periodically.  In a modified solution method, in e.g. xylene or b -ethoxyethanol, a temperature of 120 DEG  C. is used with hydroquinone or p-cresol as an inhibitor. The restrained chlorination treatment of the polymer which may be in inert solvents, e.g. chloroform, carbon tetrachloride and ethylene dichloride, is exemplified by a reaction in which chlorine is bubbled through a solution of polydichlorbutadiene at 70 DEG  C.  The polymer is then precipitated with methanol, filtered and dried.  Copolymers may be formed with vinyl chloride, bromide, acetate and butyrate; vinyl methyl or ethyl ketone; vinyl ethyl ether; styrene, monochloro- or 2,5-dichlorostyrene, a -methyl styrene; vinyl pyridine and carbazole, vinylidene chloride and fluoride; methyl isopropenyl ketone; acrylic or methacrylic acid, ethyl, n-butyl, ethyl hexyl acrylates, methyl, propyl and lauryl methacrylate, acrylonitrile, a -methacrylonitrile, acrylamide; 3-methylene - 1,4 - dioxaspiro - 4,5 - decane; diethyl maleate and fumarate; maleic anhydride; and a -cyanoacrylic acid together with doubly unsaturated compounds which are mutually conjugated or cross-conjugated, e.g. butadiene-1,3, chloroprene, isoprene, 2,3-dimethylbutadiene-1,3, fluoroprene, methyl pentadiene and divinyl ketone.  Plasticizers, e.g. phenyl and substituted phenyl salicylates with not more than 22 carbon atoms in the substituent, for instance 2,4-diamyl phenyl salicylate and 2-methyl-phenyl salicylate, stabilizers, e.g. mercaptols, normal stannous salts of catechol and alkylated catechols with phenyl salicylate, pigments, lakes, delustrants, metallic powders and oil-soluble dyes may be present and the resin may be coagulated together with butadiene-styrene copolymers.  The products may be extruded as fibres, artificial straws, tubing, films, sheets, contoured sections and filaments, which may be air-cooled and the coarser products quenched in water.  The quenched extrudate is elongated and the crystals oriented by drawing rolls, snubbing pins or dies either in one direction or simultaneously in two directions. Improved tensile strength may be obtained by further heat treatment at 80-160 DEG  C. without restraint or with sufficient tension to prevent shrinking.  In a modified after treatment for thicker articles the resin is melted, extruded, cooled slowly then re-heated to temperature of 10-60 DEG  C. below the softening point of the resin and stretched.  The products are resistant to chemicals, heat, light and water vapour and filaments thereof may be used in upholstery, luggage, drapery or shoe fabric, cordage, haberdashery or insect screens and films may be used for food packaging.  U.S.A. Specifications 1,965,369 and 2,445,739 are referred to.