ADMIXTURE OF SLUMP LOSS REDUCED TYPE AND COMPOSITION USING SAID ADMIXTURE

摘要

PURPOSE:To obtain the subject mixture providing mortar or concrete composition having excellent initial fluidity and small change of fluidity with time at low cost, by adding a basic salt of a copolymer mixture prepared by reacting a specific light oil component with an unsaturated dicarboxylic acid anhydride to cement mixture. CONSTITUTION:For example, a light oil component such as coal tar naphtha fraction or a fraction obtained by removing benzene, toluene, xylene, etc., from light oil of coke oven gas, containing preferably =25wt.% indene is reacted with an unsaturated dicarboxylic acid anhydride containing olefinic double bond, such as maleic anhydride to give a copolymer mixture having the molar ratio of the sum of (methyl)indene, coumarone and dicyclopentadiene and unsaturated dicarboxylic acid anhydride of 2/1-3 and 200-10,000 molecular weight. Then the copolymer mixture is processed into a basic salt of alkaline (earth) metal, ammonium salt or amine salt, which is contained to give the title admixture.