| 摘要 |
<p>1437007 Tire treads FIRESTONE TIRE & RUBBER CO 29 May 1973 [8 June 1972] 25619/73 Heading C3P Tire treads are prepared by introducing into a mould a mixture comprising (a) sulphur in free or combined form, (b) an elastomer precursor which is a polyhydroxy polymer derived from a polymer selected from (1) homopolymers and copolymers of C 4 -C 6 conjugated dienes and (2) copolymers of such dienes with a vinyl aromatic monomer or vinyl nitrile monomer, (c) a polyisocyanate and (d) sufficient reinforcing pigment to make the composition serviceable as a tire tread, there being at least 25 weight per cent of (b) and (c) in the tread and the NCO/OH ratio being at least 0À5, and subjecting the mixture to curing conditioner. The polymer may be derived from butadiene, isoprene, chloroprene or piperylene, optionally with styrene,α-methylstyrene, vinylnaphthalene, acrylonitrile or methacrylonitriles. The mixtures may contain other elastomers, e.g. scrap or reclaim rubbers, and conventional compounding ingredients. Examples describe the formation of tire treads and compositions from mixtures comprising sulphur and accelerators, hydroxy-terminated butadiene/styrene copolymers, toluene diisocyanate, carbon black or zinc oxide and dibutyl tin dilaurate, with and without liquid and solid polybutadienes, processing oils, zinc stearate, stearic acid and 4,4<SP>1</SP>-methylene bis(2,6-di-t-butylphenol).</p> |
