GB811847A - Improvements in or relating to the production of substances of high molecular weight - Google Patents

Abstract

A high molecular weight substance is produced from a polymerizable organic liquid by bringing the liquid into a condition having an extended surface area and then exposing it to the radiation of charged particles, e.g. electrons. The liquid is irradiated for example in the form of droplets or as a thin film which may be supported on a metal net. The beam of electrons, which is produced in a vessel at low pressure, may pass through chambers at intermediate pressures into the treatment vessel which is at atmospheric or higher pressure. To assist polymerization, <PICT:0811847/III/1> <PICT:0811847/III/2> liquid containing solid nuclei from a previous process is added to the liquid treated; inorganic powders may also be added. Solid substances separated from the product may be worked up into threads or moulded. As shown in Fig. 1, the liquid is supplied from container 10 to tank 9 which is arranged in evacuated chamber 6; ultrasonic generators 13 disperse droplets of the liquid into the space above the tank 9 where they are irradiated by an electron beam from cathode 28 and fall to the bottom of chamber 6, collecting in container 17; a recirculation system 18, 19 is provided. In an alternative arrangement, tank 9 has an inclined floor from the lower part of which polymerized solids are removed. In the apparatus of Fig. 3 liquid films flow over trays 37 and are irradiated by electron beams from sources 32; the polymerized molecules become oriented by the action of an electrostatic field between walls 38 and 40. In another apparatus, Fig. 4 (not shown), liquid is dispersed into droplets by an electrostatic field. Another dispersing device, Fig. 6 (not shown), comprises a rotatable hollow axis provided with holes leading to discs; liquid fed into the axis is thrown off the edges of the rotating discs. In order to prevent droplets of liquid passing from the treatment vessel to the electron beam source, the electron beam may pass through cooled intermediate chambers, being bent through connecting slits by means of magnetic fields (see Group XL (a)). In place of electron beams, radition from radioactive substances may be used, or the material to be treated may be conveyed through a nuclear reactor. Reference is made to the polymerization of mineral oil, octyl phthalate, diallyl phthalate, and butyl acrylate.ALSO:A high molecular weight substance is produced from a polymerizable organic liquid by bringing the liquid into a condition having an extended surface area and then exposing it to the radiation of charged particles, e.g. electrons. The liquid is irradiated for example in the form of droplets or as a thin film which may be supported on a metal net. Solid substances separated from the product may be worked up into threads or moulded. Apparatus for carrying out the process is described (see Group III). In place of electron beams, radiation from radioactive substances may be used, or the material to be treated may be conveyed through a nuclear reactor. Reference is made to the polymerization of mineral oil, octyl phthalate, dialkyl phthalate, and butyl acrylate.