| 摘要 |
Distinct pigment particles are coated with at least one amorphous polyolefinic material by dispersing the pigment in a solution of the amorphous polyolefin in a non-polar solvent, and thereafter introducing a non-solvent for the amorphous polyolefin in a controlled manner to cause the amorphous polyolefin to coat each particle individually. The coated particles are then incorporated into polyolefins. Amorphous polypropylene is made by polymerizing propylene in the presence of (A) ethyl aluminium sesquibromide and tetra-2-ethyl-hexyl titanate, and (B) lithium aluminium hydride, sodium fluoride, and titanium trichloride. Amorphous ethylene-propylene block copolymer is made by alternately adding propylene and ethylene to catalyst A. Amorphous polyallomer is made by polymerizing propylene and then ethylene in the presence of catalyst B. |
