Pitch-based sealing, casting and cladding compsns. - contain PVC plastisol, latex and filters, have good elasticity over wide temp. range

摘要

Compsns. (I) comprise (A) pitch, (B) 12-44% (all pts.wt.) paste of PVC in plasticiser, (C) 2-14% latex, (D) fillers, and opt. (E) additives. Prepn. of (I) by introducing first (B) and (A) at above 105 deg.C and homogenising then adding (C) followed by (D) and (E), and homogenising at 110-150 deg.C. PVC has Fikentscher no. 55-75 and plasticiser is pref di-Bu phthalate. (C) comprises polychloroprene and/or butadiene-styrene latex. (I) also contain 0.4-7.0% amino-phenol resin and/or colophony resin. Partic. (I) comprises 45-60% normal pitch, 20.5-32.5% PVC plastisol comprising 5.5-7.5% PVC and 15-25% phthalate plasticiser and opt. stabilisers, 5.5-8.0% butadiene-styrene latex, 5-20% fillers and additives, 0-5.0% thixotropic agent, and 0-3.5% colophony and/or amino-phenol resin. USE/ADVANTAGE - As sealing compsns., partic. for expansion joints in buildings and constructions subject to mechanical and thermal deformation, as casting material, and cladding compsns. for waterproofing (all claimed). (I) have good elasticity over wide temp. range, partic. at down to -20 deg.C. Cancerogenic potential is lessened due to redn. in benzo(a)pyrene content from pitch in (I) and because (I) do not adhere to skin.