GB639199A - The production of patterned sheets of polymeric resin - Google Patents

Abstract

Sheets of polymeric resin are produced from one or more unsaturated organic compounds having one and one only CH2=C< group, e.g. methyl methacrylate, styrene, vinyl acetate and methyl a -chloracrylate, by polymerization of the monomeric and/or partially polymerized material in contact with one or more forming surfaces at least one of which is made from a different solid thermoplastic resin, insoluble in the compounds polymerized at the polymerization temperature, and which is free from polymerization inhibitors and other substances miscible with the unsaturated compounds. Preferably the process is carried out in a flat chamber the side walls of which are rigid but capable of relative movement to compensate for contraction during polymerization. The forming surfaces may be plain or patterned and made from polythene, polytetrafluoroethylene, nylons, "Terylene" (Registered Trade Mark), and polyvinyl alcohol. In examples, plain or ribbed sheets of polythene are prepared by sintering polythene granules between heated chromium plated steel platens which have been wiped with a solution of oleyl sodium sulphate as separating aid. A cell, constructed from two sheets separated by a resilient gasket and backed with glass plates was filled with a syrup of partially polymerized methyl methacrylate containing benzoyl peroxide and heated at 40 DEG C. The polymethacrylate sheet obtained was further heated at 90 DEG C. on a smooth glass plate. Specifications 433,540, 445,927, [Group III], 450,305, 460,239, 460,240, 469,564, 474,242, 475,552, 477,364, 482,194, 484,343, 567,777, 567,778, 569,684, 582,559, 592,652, 597,498, 612,070 and 618,124 are referred to.ALSO:Polymeric resin sheets are made by polymerizing monomeric or partially polymerized material, e.g. methyl methacrylate, in contact with one or more plain or patterned forming surfaces at least one of which is made from a different thermoplastic resin, e.g. polythene, polytetrafluoroethylene, nylon, "Terylene" (R.T.M.) and polyvinyl alcohol. The process is preferably carried out in a flat chamber, the side walls of which are rigid, but capable of relative movement to compensate for contraction during polymerization. In examples plain or ribbed sheets of polythene are prepared by sintering polythene granules between heated chromium plated steel platens which have been wiped with a solution of oleyl sodium sulphate as separating aid. A cell constructed from two sheets separated by a resilient gasket and backed with glass plates was filled with a syrup of partially polymerized methyl methacrylate containing benzoyl peroxides and heated at 40 DEG C. The sheet thus obtained was further heated at 90 DEG C. on a smooth glass plate. Specifications 433,540, 445,927, [Group III], 450,305, 460,239, 460,240, 469,564, 474,242, 475,552, 477,364, 482,194, 484,343, 567,777, 567,778, 569,684, 582,559, 592,652, 597,498, 612,070 and 618,124 are referred to.