| 摘要 |
PROBLEM TO BE SOLVED: To decrease the extrusion pressure and to improve formability, fluidity, surface smoothness, bending strength, etc., by using a single polymer or copolymer of a specified compd. as the main component of the admixture. SOLUTION: This admixture for a cement extruded product is obtd. by (co) polymn. of 20-100wt.% compd. expressed by formula I (R<1> and R<2> are each H or methyl groups), 0-80wt.% of a compd. expressed by formula II (R<3> is H or a methyl group, R<4> is 1-4C straight-chain or branched-chain alkylene group, X<1> is H, alkali metals, ammonium salt or org. ammonium salt), and 0-40wt.% of a compd. expressed by formula III in the presence of a radical polymn. initiator. In formula III, R<5> is H or a methyl group, X<2> is CN, COOR<6> , CONH2 , CONHR<7> , COR<8> , OCOR<9> , OR<10> , R<6> is an alkali metal, ammonium salt, or 1-4C alkyl group (wherein H in the alkyl group can be replaced by OH or 1-4C di-substd. alkylamino group), and R<7> -R<10> are 1-4C alkyl groups. When the admixture is dissolved in a supernatant of a cement, the soln. has 100 to 10,000cps viscosity (with 1.2wt.% measured by a B-type rotary viscometer). |
