Preparation method of polypropylene for preparation of chlorinated polypropylene with high chlorination rate

Abstract

The invention relates to a preparation method of polypropylene for preparation of chlorinated polypropylene with a high chlorination rate, which comprises the following steps: adding 3-20mmol of aluminium alkyl hexane solution into 1000ml of straight-chain saturated paraffin or straight-chain saturated paraffin mixture; adding 0.1-0.5g of catalyst per ml of straight-chain saturated paraffin or mixture with straight-chain saturated paraffin; and adding 10-150mul of orthosilicate component per g of catalyst, adding 10-150mul of dicarboximide compound per g of catalyst and filling gas mixture of propylene and hydrogen. The catalyst is a Ziegler-Natta catalyst; the straight-chain saturated paraffin is hexane or octane; the straight-chain saturated paraffin mixture is mixture of nonane and decane; and the dicarboximide compound is 2, 2, 6, 6-4-methylpyridine. As to the polypropylene, the melt flow index is 20-50g / 10min, the isotacticity is 91-95 percent, the crystallinity is 40-54 percent and the bulk density is higher than 0.38g / cm3.

Description

Technical field:

[0001] The invention relates to a polypropylene preparation method for preparing high chlorination rate chlorinated polypropylene. Background technique:

[0002] As an important synthetic resin, polypropylene is widely used. The different properties of polypropylene determine its use. At present, due to the requirements of the polymerization process, the polypropylene prepared by the slurry method generally has a high isotacticity (above 97%), a high degree of crystallinity (above 60%), and the melting index of industrial powder products is difficult to determine. to very high (higher than 20g / 10min). Unable to meet the needs of some specific uses. For example, it is used in the production of chlorinated polypropylene by the aqueous phase suspension chlorination method. The aqueous phase suspension chlorination method requires polypropylene to have both uniform powder, relatively low isotacticity and crystallinity, and a high melt index at the same time. ...