| 摘要 |
<p>A concrete tile (I) is claimed, which is coated with a copolymer (A) with Tg -25 to +30 deg.C, derived from (a) 0.1-10 wt.% monomer of formula R1CH=CR2-CO-X-R3-Z-CHR4R5 (III), (b) 85-99.9 wt.% at least 2 monomers of the type (1-24C alkyl) (meth)acrylates, vinyl esters of 1-20C carboxylic acids, up to 20C vinylaromatics, 3-6C unsatd. nitriles, vinyl halides and/or 2-8C non-aromatic hydrocarbons with olefinic double bond(s), and (c) 0-10 wt.% other Sn-free comonomers; R1, R2 = H or 1-4C alkyl; R3 = 1-20C bridging gp.; R4 = -COR6, -COOR6 or CN; R5 = H, -COR9, -COOR9 or CN; X = O or NR7; Z = single bond, CH2, O, NR8 or -OCO-; (with R6-R9 = H, or 1-12C alkyl, aryl, alkaryl or aralkyl). Also claimed is a process for the prodn. of (I), by application of an aq. prepn. contg. (A) to at least one surface of the green concrete, and drying the prepn. by hardening the concrete. More specifically, monomer (a) is acetylacetoxyethyl (meth)acrylate, acetylacetoxybutyl (meth)acrylate, cyanoacetoxyethyl (meth)acrylate, 1,1-dibenzoyl-2-(meth)acrylamidoethane, 1-benzoyl-1-acetyl-2- (meth)acrylamidoethane, or ethyl alpha-benzoyl-beta-(meth) acrylamidopropionate, and (b) are vinylaromatics or (1-8C alkyl) (meth)acrylates; (I) is coated with a prepn. contg. copolymer (A) and up to 450 wt.% mineral additives (B) and/or colour pigments (C) (w.r.t. amt. of A); another layer of the aq. prepn. is applied to the hardened tile and dried; the amt. of prepn. used is such that the total amt. of dry coating is 50-500 g/m2.</p> |
