| 摘要 |
<p>The binder consists of (a) a conc. aq. soln. of acid to neutral salts of multi basic, weak to medium strong acids contg. oxygen, with metal-oxides or hydroxides with a basicity which decreases with increasing valancy; (b) solids, consisting of sec. and/or tert. salts; (c) oxides with high valency; and (d) at least one oxidn. and redn. agent. In this addn., substance (d) is the oxyacid or oxybase of a semimetal. The salts used in soln. (a) may be obtd. from the oxyacids of the semimetals, or using the basic oxides or hydroxides of a semimetal or transition metal; and the ratio acid:basic oxide or hydroxide is pref. 3:1-1:1. In addn. to acting as a binder, the mixt. can be used to activate materials, e.g. for mfg. light expanded concrete; for pigmenting; or as a glaze. In an example, a mixt. of granular stone and binder was made with compsn. 33 pts. wt. basalt, size 0.63-2 mm; 33 pts. wt. basalt, size 0.09-0.63 mm; 16.5 pts. wt. basalt fluor below size 0.09 mm; 3-6 pts. wt. sodium silicate (20% H2O); 1.54 pts. wt. MnO2; 2.57 pts. wt. Sb2O3; 12.5 pts. wt. water. The mixt. was moulded, dried, and hardened at 200 degrees C. to obtain hard mouldings insol. in water due to the presence of Sb2O3.</p> |
