A kind of catalyst component for olefin polymerization and its catalyst and application

Abstract

The invention discloses a catalyst component for olefin polymerization or copolymerization as well as its catalyst and application. The catalyst component is obtained through the following steps: (1) contacting a magnesium compound, an organic epoxy compound, and an organic phosphorus compound in a solvent to form a uniform solution; (2) in the presence of a phenolic compound eluting agent, the obtained The homogeneous solution is contacted with a titanium compound to obtain a mixture; (3) the mixture obtained in step (2) is contacted with an electron donor compound, filtered, washed and dried to obtain a titanium-containing catalyst component for olefin polymerization. The catalyst component of the invention has high catalytic activity when used in propylene polymerization and copolymerization, and the activity decays slowly.

Description

technical field [0001] The present invention relates to a catalyst component for olefin polymerization or copolymerization, its catalyst, and its application in olefin polymerization or copolymerization. Background technique [0002] In the late 1970s, companies such as Mitsui Petrochemical Corporation of Japan and Monai of the United States successfully developed titanium-magnesium high-efficiency carrier catalysts with magnesium chloride as the carrier. Because the carrier was used to improve the utilization rate of the active center of the titanium atom, the catalytic activity was improved. It is much higher than conventional catalysts and simplifies the polymerization process, so the world's polyolefin industry has developed rapidly. Conventional methods for preparing highly active supported catalysts are generally co-grinding, grinding and impregnating, spraying carrier forming and high-speed stirring carrier forming, etc. The main disadvantage of the catalyst obtained...

AI Technical Summary

Problems solved by technology

When the catalyst system is used for propylene polymerization, the obtained polymer has high isotacticity and high apparent density, but the catalyst activity is not high

[0004] The technology of forming the support in the above two ways to further prepare catalyst components has developed to a certain extent, mainly in the development of internal electron donors, such as diethers and succinates developed by BASELL, which are used to improve catalyst activity, Improve the hydrogen regulation performance of the catalyst, increase the molecular weight distribution of the product to improve the processing performance, but the increase in catalyst activity is mainly in the early stage of the polymerization reaction, and the activity decays quickly, so because the high activity in the early stage is not conducive to polymer production control, the production of copolymerization When using propylene, there are problems such as insufficient activity in the later stage, and the production process of this type of internal electron donor is generally complicated and the production cost is high, so the production cost of the catalyst is correspondingly high

[0005] Chinese patent CN1453298A discloses a class of glycol ester compounds containing a special structure as electron donors. The use of such electron donors can not only improve the activity of the catalyst, but also significantly broaden the molecular weight distribution of the obtained propylene polymer, but the catalyst activity is limited. The improvement is also mainly in the early stage of the polymerization reaction, and the activity decays quickly. At the same time, the synthesis and purification process of this type of diol ester compound is complicated, which makes the catalyst production cost higher.

[0006] Generally speaking, there are many technologies to improve catalyst activity in the prior art, but the improvement of catalyst activity is usually accompanied by the acceleration of activity decay, which has a negative impact on the application of catalysts.