摘要 |
<p>Sticky polymers are produced at polymerisation temps. above the softening pt. of the polymers in a fluidised bed of a supported catalyst and an inert particulate material. The process is improved by the use, as catalyst support, of a silica having average particle size 60-200 micron with a wt. fraction of no more than 30% smaller than 44 microns. Also claimed is a process as above for producing ethylene-propylene-ethylidene norbornene terpolymer, the silica support having avge. particle size 70-140 microns with a wt. fraction of no more than 20% smaller than 44 microns. Pref. the inert particulate material is pref. from C black, silica, or clay esp. C black having prim. particle size 10-100 nm, average aggregate size 0.1-10 microns, specific surface area 30-1500 m2/g, and dibutylphthalate absorption 80-350 cm3/100g. The silica support pref. has average pore dia. greater than 100 Angstrom, surface area greater than 200 m2/g, and average pore vol. 1.4-2.0 ml/g. The inert particulate material is pref. introduced at a point above the fluidised bed.</p> |