GB1083486A - Elastic gap-filling composition - Google Patents

Abstract

An elastic gap-filling composition is produced by polymerizing a monomeric methacrylate ester and at least one acrylate ester in the presence of at least one methacrylate ester/acrylate ester copolymer, and at least one paraffin wax soluble in the mixture, using an initiator effective at - 10 DEG to 50 DEG C. At least one cross-linking agent may also be included. Specified methacrylates are methyl, i-propyl, i-butyl, n-butyl and dodecyl methacrylate and the preferred acrylates have 3 to 18 carbon atoms in the ester group, e.g. linear and/or branched butyl, hexyl, octyl, 2-ethylhexyl, decyl, dodecyl or stearyl acrylates. The preformed copolymer may be present as a monomer/polymer syrup. Cross-linking agents specified are di(meth)acrylates of a dihydric alcohol such as ethylene, diethylene, triethylene, polyethylene, propylene, dipropylene, butylene or hexylene glycols, a divinyl compound, e.g. divinyl benzene and diallyl compounds, e.g. diallyl phthalate. Suitable catalysts are redox ones comprising a peroxide, preferably acyl, and a tertiary amine, preferably aromatic, with or without other accelerators, promoters and co-catalysts. Organic sulphur compounds, preferably mercaptans, may be used as modifiers. Suitable plasticizers, stabilizers and fillers are listed and pigments may also be included in the reaction mixture. In Example 1, 2-ethylhexyl methacrylate and methyl methacrylate are mixed with a n-butyl acrylate/methyl methacrylate copolymer, ethylene glycol dimethacrylate, lauryl mercaptan, paraffin wax, dimethyl aniline, a solution of benzoyl peroxide and dibutyl phthalate, crushed slate and silica and polymerized in a gap between two concrete sections. In Example 2, methyl methacrylate and n-butyl acrylate are mixed with a 2-ethylhexyl acrylate/methyl methacrylate copolymer, a chlorinated diphenyl, triphenyl phosphite, 2-(21-hydroxy-51-methylphenyl)-benzotriazole, dimethyl-p-toluidine, triethylene glycol diacrylate, paraffin wax, the aforesaid peroxide solution, BaSO4 and SiO2 and polymerized between two structural components consisting of foam concrete externally lined with P.V.C.-coated steel. 2-Ethylhexyl acrylate and methyl methacrylate are mixed in Example 3 with a methyl methacrylate/ethyl acrylate copolymer, a polyester of adipic acid and butylene glycol, dimethyl-p-toluidine, triethylene glycol dimethacrylate, paraffin wax, the catalyst mixture as in Example 1, crushed slate and SiO2 and polymerized in a crack in a concrete tank. In Example 4, 2-ethylhexyl acrylate and methyl methacrylate are mixed with methyl methacrylate/2-ethylhexyl acrylate and n-butyl methacrylate/methyl methacrylate pre-polymers, triethylene glycol dimethacrylate, dimethyl p-toluidine, lauryl mercaptan, paraffin wax, the catalyst system of Example 1, and kaolin, and polymerized in joints between P.V.C.-lined sheet-steel tiles.