METHOD OF PREPARING RADIATION-PROTECTION REFRACTORY COMPOSITE Russian patent published in 2003 - IPC

FIELD: radiation protection. SUBSTANCE: composition is prepared from binding agent, 5.0-10.0%, and filler, 90.0-95.0%. The former is ethylsilicate-40 and the latter barium sulfate activated by iron hydroxide with Ba/Fe ratio 2.5-4.0 and modified with hydrolyzed ethylsilicate-40 at 20-25 C for 15-30 min, dried at 550-600 C, and ground into fraction 0.009-1.0 mm. Further, samples are molded at specific pressure 450-555 kg/sq.cm and caked for 35-40 min at 1100-1150 C. Modification is performed in the course of preparing hydrolyzed ethylsilicate- 40, which is mixed with distilled water (1:1) and with iron hydroxide-activated barium sulfate at solid phase-to-liquid phase ratio 2, after which 20% ammonia solution is added. The following percentages are employed, wt. %: iron hydroxide-activated barium sulfate, 62.0-65.0; ethylsilicate-40/distilled water mixture, 30.0-35.0; ammonia solution, 3.0-5.0. EFFECT: improved physicomechanical properties and radiation-protection characteristics. 5 tbl