GB179208A - Improvements relating to the manufacture of plastic materials or articles having a basis of cellulose acetate - Google Patents

Abstract

Cellulose acetate, preferably dry, is mixed in the absence of volatile solvents with not more than 50 per cent of its weight of a plastifying or softeningagent not saponifiable with water, with or without dyes, filling substances &c., and heating during the mixing &c. to a temperature of 100-150 DEG C. or higher to melt the acetate in the plastifying agent. The mass, with or without subsequent working on rollers may be moulded under heat and pressure, cast, run into sheets or films, extruded through dies &c. According to an example, 100 parts of ground air-dried cellulose acetate are kneaded with 30-40 parts of isomeric xylene-o-monomethyl sulphonamides as described in Specification 132,283, with or without 6-8 parts of triphenol- or tricresylphosphate the mass being heated during the kneading to 100-150 DEG C. or higher, a vacuum being applied if desired. Dyes and filling materials may be added and the mass may be worked between rollers heated to a higher temperature than usual, for example, 90-100 DEG C., and moulded, pressed, cast, extruded, &c. The Provisional Specification also states that volatile non-solvents such as benzol may be employed to facilitate mixing.