| 摘要 |
<p>Prodn. of very fine and easily dispersible CaCO3 particles, by carbonating, using CO2 an aq. suspension contg. 40-15g/l. Ca(OH)2 at 20-75 deg.C and in presence of 0.2-5% wt. of a first additive from a grp. of mono-, di-saccharides or monocarboxylic polyfunctional alcohols and in presence of 0.2-5% wt. of a 2nd. additive e.g. active Si compd. or a solubilised starch. This CaCO3 can be obtd. as fine, even particles over a wide temp. range and they are easily filtered out of the soln. They are used as fillers in certain polymers e.g. ethylene-propylene terpolymers and decrease the time of curing of the polymer. Sucrose and gluconic acid as the first additive and Na silicate or solubilised starch as the second additive.</p> |
