Patent GB-851647-A (GB)
Title: Improvement in processes for the preparation of shaped objects based on polymerised substances
IPC: C08F291/18
Filed: 1958-11-14
Abstract: In a process for preparing shaped articles of polymerizable substances a stem polymer is impregnated with at least an equal weight of a polymerizable monomer in the form of an unsaturated vapour, and the impregnated polymer is subjected to ionizing radiation.  The polymer may consist of a polyvinyl ester, alcohol, or acetal, a cellulose ester, or regenerated cellulose, and the monomer is preferably of the acrylic type, e.g. methyl methacrylate.  The ionizing radiation may be that emitted by natural or artificial radio-active sources, or that obtained from particle accelerators or by bombarding a metal plate with electrons.  The polymerizable substances may be shaped before impregnation and re-shaped before being irradiated.  In one example a sheet of polyvinyl chloride is treated with unsaturated methyl methacrylate vapour and then subjected to the gamma radiation produced by bars of radiocobalt.  In a further example unplasticized polyvinyl chloride powder is treated with unsaturated methyl methacrylate vapour, and the impregnated powder is extruded to form a sheet which is subjected to the radiation emitted by a 500,000 electron volt-particle accelerator. Reference has been directed by the Comptroller to Specification 801,528.ALSO:In a process for preparing shaped articles of polymerizable substances a stem polymer is impregnated with at least an equal weight of a polymerizable monomer in the form of an unsaturated vapour, and the impregnated polymer is subjected to ionizing radiation.  The polymer may consist of a polyvinyl ester, alcohol, or acetal, a cellulose ester, or regenerated cellulose, and the monomer is preferably of the acrylic type, e.g. methyl methacrylate.  The ionizing radiation may be that emitted by natural or artificial radio-active sources, or that obtained from particle accelerators or by bombarding a metal plate with electrons.  The polymerizable substance may be shaped before impregnation and reshaped before being irradiated.  In one example a sheet of polyvinyl chloride is treated with unsaturated methyl methacrylate vapour and then subjected to the gamma radiation produced by bars of radio-cobalt.  In a further example unplasticized polyvinyl chloride powder is treated with unsaturated methyl methacrylate vapour, and the impregnated powder is extruded to form a sheet which is subjected to the radiation emitted by a 500,000 electron volt-particle accelerator.  Reference has been directed by the Comptroller to Specification 801,528.ALSO:In a process for preparing shaped articles of polymerizable substances a stem polymer is impregnated with at least an equal weight of a polymerizable monomer in the form of an unsaturated vapour, and the impregnated polymer is subjected to ionizing radiation.  The polymer may consist of a polyvinyl ester, alcohol, or acetal, a cellulose ester, or regenerated cellulose, and the monomer is preferably of the acrylic type, e.g. methyl methacrylate.  The ionizing radiation may be that emitted by natural or artificial radioactive sources, or that obtained from particle accelerators or by bombarding a metal plate with electrons.  The polymerizable substance may be shaped before impregnation and reshaped before being irradiated.  In one example a sheet of polyvinyl chloride is treated with unsaturated methyl methacrylate vapour and then subjected to the gamma radiation produced by bars of radio-cobalt.  In a further example unplasticised polyvinyl chloride powder is treated with unsaturated methyl methacrylate vapour, and the impregnated powder is extruded to form a sheet which is subjected to the radiation emitted by a 500,000 electron volt-particle accelerator.  Reference has been directed by the Comptroller to Specification 801,528.