GB1105680A - Thermoplastic materials and process for producing same - Google Patents

Abstract

Granular particles of thermoplastic materials are coated with a layer of polyethylene wax having a powdered material dispersed therein and compatible with said wax, said wax being solid at the temperature of at least 30 DEG C. the granules may be of homo-polymers and interpolymers of monomers containing the group <FORM:1105680/B1-B2/1> where R1 is H, F or Cl and R2 is H, alkyl, aryl or halogen. Exemplified are homo- and inter-polymers of ethylene, propylene, isobutylene, vinyl halides, e.g. vinyl chloride, vinylidene chloride, vinyl esters of carboxylic acids, e.g. vinyl acetate, vinyl propionate, vinyl benzoate, vinyl ethers, e.g. vinyl methylether, vinyl ethyl ether, and saturated carboxylic acids, and derivatives thereof, e.g. acrylic acid, methacrylic acid, acrylamide, acrylonitrile, polyesters of e.g. terepthallic acid esters, vinyl aromatic compounds, e.g. styrene, vinyl napthalene, as well as tri-chloroethylene, tri-fluoroethylene, tetrafluoroethylene, chlorotrifluoroethylene, dialkyl fumarates and 1, 2-dichloroethylene. Powdered materials which may be used are fillers, dyes and pigments, powdered metals, e.g. aluminium and copper, inorganic oxides, for example titanium dioxide and ferric oxide, and salts such as lead chromate, sulphates and arsenates may also be used. Organic pigment such as prussian blue, gamboge, and carbon black are also specified. The powdered material may be of 1 millmicron to 1,000 microns in size. The thermoplastic granules and wax may be introduced into a heated vessel in a number of ways. The granules and powdered wax may be introduced separately and directly into the vessel, or they may be first pre-blended and the blend then introduced into the vessel where the granules can be sprayed with molten wax by passing them into the spray thereof, after which they are introduced into the vessel. The vessel is maintained at at least the melting point of the wax.