POLYMERIC MAGNETIC COMPOSITE AND ITS PRODUCTION PROCESS Russian patent published in 1999 - IPC

FIELD: production of polymeric bond magnetic composites for manufacturing thin magnets of intricate shape. SUBSTANCE: additionally introduced in polymeric magnetic composite incorporating magnetic powder, castor oil, and thermoplastic are dioctyl phthalate or dibutyl phthalate, laminated aluminosilicate, and polypropylene as thermoplastic, proportion of ingredients is as follows, mas.%: magnetic powder, 93- 95.5; castor oil, 0.1-0.3; dioctyl phthalate or dibutyl phthalate, 0.5- 1.3; laminated aluminosilicate, 0.15-0.3; polypropylene, the balance. Production process involving mixing of ingredients followed by molding also includes pre-tribactivation of polypropylene powder in steel blade-type high-speed mixer running at 1000-1100 rpm for 20-30 min which is then introduced in mixture of magnetic powder, castor oil, dioctyl phthalate or dibutyl phthalate followed by mixing composite obtained in the process with laminated aluminosilicate in thermoplastic melt. EFFECT: improved filling degree of composite materials based on rare-earth alloys and thermoplastics, reduced power requirement for manufacturing permanent magnets from them. 2 cl, 2 tbl