Polyethylene and polypropylene extrusion and moulding compsns. - contg. granulated additive mixt. of calcium carbonate, polyethylene or polypropylene resin and polyethylene wax

摘要

Granulated additive mixt. for thermoplastics, esp. high- and low-pressure polyethylene and propylene (co)polymers, consists of 65-75% CaCO3 (I), 25-35% polyethylene-(IIA) or polypropylene resin (IIB) and 1-5% polyethylene wax (III). Used in foil-, sheet-, pipe- and profile extrusion and in blow- or injection moulding. The additive does not impair shaped article strength and transparency. In extrusion, (i) hollow bodies, pipes and profiles have a higher rigidity and higher impact tenacity; (ii) a light lubricating activity is achieved; (iii) cycle time is reduced; (iv) heat-oxidn. is reduced and (v) the adhesion of foils, plasma-treated on both sides, and blocking are prevented. In injection moulding, cycle times are reduced and melt indices are increased slightly.