POLYMER FRICTION COMPOSITION (VARIANTS) Russian patent published in 1997 - IPC

FIELD: production of asbestos-free friction materials for coatings of braking units which operate in heavily loaded friction devices. SUBSTANCE: polymer friction composition comprises, mas.%: resol phenol-formaldehyde resin, 13-15; butadiene acrylonitrile rubber, 3-5; aramide fiber, 2.5-3.0; basalt fiber which surface is modified by 3-4 mass % of polyorganohydride siloxane, 8-10; wollastonite which surface is modified by 2-10 mass % of carbon modifier, 10-12; alumina, 4-8; graphite, 1-2; copper powder, 10-15; bronze chips, 10-15; barite, up to 100. According to the second variant similar to the first one wollastonite which surface is modified by 3-4 mass % of polyorganohydride siloxane is proposed for using. Composition is prepared by mixing at 90 C within 15-18 min, the process is carried out in rubber mixer. After sustaining within 1-7 days thus prepared material is ground and formed initially in cold mold and then in hot mold at 190 C and at 30-40 MPa. Article is affected by heat treatment at 200 C, the process is carried out within 2-3 h in furnace. EFFECT: improved physical and mechanical characteristics, increased wear resistance. 3 cl, 2 tbl