SOLID POLYMER COMPOSITIONS HAVING FLAME RETARDANT AND DRIP RESISTANT PROPERTIES AND ADDITIVE COMPOSITIONS FOR IMPARTING SAID PROPERTIES THERETO

摘要

Compositions comprise a synthetic thermoplastic polymer, selected from polyamides, polystyrene and polyolefins derived from straight-chain olefins, one or more flame retardants and up to 10 weight per cent based on the polymer of an organophilic cation-modified clay. Specified polymers are polyethylene, polypropylene, polystyrene and nylon. Specified fire retardants are chlorinated paraffins, trichlorethyl phosphate, tribromophenol, ammonium chloride, ammonium bromide, phosphoric acid esters, antimony trioxide and arsenic trioxide. The clay may be a medium or high exchange capacity clay modified with an onium base, e.g. an ammonium, phosphonium, arsonium, stibonium, oxonium, sulphonium, selenonium, telluronium, stannonium or iodonium base, or associated with an aliphatic amine containing at least 12 carbon atoms, or a derivative thereof such as may be obtained by fusing said amines with stearamide, stearonitrile or cetyl alcohol. The compositions may comprise other conventional ingredients such as plasticizers, pigments, fillers, stabilizers, anti-oxidants and antistatic agents. The clay may be dispersed in a volatile or non-volatile medium, e.g. trichlorethylene, toluene, xylene, white spirit, paraffin wax or polyethylene wax; and is preferably treated with an organic polar liquid, e.g. methanol, acetone, methyl ethyl ketone or propylene carbonate, before incorporation in the polymer. Alternatively a polymer additive may be prepared by mixing the clay and flame retardant in the presence of a volatile organic liquid, adding the polar liquid and then mixing and evaporating the liquids to obtain a mixture in gel form. Examples describe compositions comprising polyethylene, dimethyl dioctadecyl ammonium hectorite and (1-4) chlorinated paraffin and antimony trioxide, (5 and 6) trichlorethyl phosphate, (7 and 8) tritolyl phosphate and (13-16) chlorinated paraffin; polyethylene, dimethyl dioctadecyl ammonium montmorillonite and (9) ammonium bromide; polyethylene, dimethyl dioctadecyl ammonium sepiolite and (10 and 11) trichlorethyl phosphate, and (12, 17 and 18) chlorinated paraffin; polypropylene, dimethyl dioctadecyl ammonium hectorite and (19) chlorinated paraffin, (20 and 21) chlorinated paraffin and antimony trioxide, and (22 and 23) trichlorethyl phosphate; nylon 11, trichlorethyl phosphate and (24) dimethyl dioctadecyl ammonium hectorite, and (25) an organophilic zeolite clay; and polystyrene, dimethyl dioctadecyl ammonium hectorite and (26) trichlorethyl phosphate.