| 摘要 |
Compositions comprise discrete particles of average size 0.01 to 3.0 mm. of a polyolefine of M.W. above 500,000 dispersed in a continuous phase of a synthetic plastics material of higher melting point than the polyolefine. To maintain the particle size of the particles melt blending should be effected under conditions such that the melt viscosity of the polyolefine is greater than that of the other material. The only specified plastics are polyamides and polyacetals. In Example 1 18% of polyethylene (M.W. 1,200,000, particle size 0.03 to 0.5 mm.) is incorporated in nylon 6 (M.W. 70,000) with 0.3% tris(polyoxyethylene) sorbitan monolaurate to promote adhesion and in Example 2 5% of polyethylene (M.W. 1,000,000, particle size 0.04 to 0.2 mm.) is incorporated in polyoxymethylene (M.P. 175 DEG C., viscosity 35,000, at 202 DEG C. It is also stated that the compositions may be obtained by incorporating the polyolefine in an anionically polymerizing lactam. They are stated to be useful for bearings and gears. |
