Catalysts for olefin polymerization and method of olefin polymerization using the same
Described herein is a prepolymerized catalyst encapsulated with macromolecular monomers which is prepared by adding olefin mononers and diene compounds to a solid complex titanium catalyst for olefin polymerization and then polymerizing, and also relates to a method for polymerization or copolymerization capable of preparing polyolefins with high melt strength by polymerizing the olefin by using said catalyst.
1. A catalyst for olefin polymerization encapsulated with macromolecular monomers around the catalyst which is produced by treating the surface of a solid titanium catalyst for olefin polymerization with silane compounds having two or more vinyl groups and then prepolymerizing said surface treated solid titanium catalyst with olefin monomers and diene compounds.
2. The catalyst of claim 1 , wherein said solid titanium catalyst is produced by: (i) preparing magnesium compound solutions by dissolving magnesium compounds having no reducibility in electron donors, (ii) reacting said magnesium compound solutions with transition compounds, silicon compounds, tin compounds or a mixture thereof and precipitating solid particles, and then (iii) reacting said precipitated solid particles with titanium compounds and electron donors.
3. The catalyst of claim 1 , wherein said silane compound having two or more vinyl groups is divinyldimethylsilane, divinyldiphenylsilane, divinyldiethylsilane, divinyldiisobutylsilane or divinyldihydridesilane.
4. The catalyst of claim 1 , wherein the amount of said silane compounds having two or more vinyl groups used is 2˜200 moles per 1 mole of magnesium compound.
5. The catalyst of claim 1 , wherein said olefin monomer is more than one monomer selected from the group consisting of ethylene, propylene, 1-butene, 1-hexene, and 1-octene.
6. The catalyst of claim 1 , wherein said diene compound is 1,3-butadiene, 1,5-hexadiene, 1,7-octadiene, 1,9-decadiene or 1,13-tetradecadiene.
7. The catalyst of claim 1 , wherein said macromolecular monomers encapsulating around the catalyst have a molecular weight in the range of 500 to about 100,000, and is composed of 1 to about 99 weight percent of olefin, 0.01 to about 10 weight percent of diene, and 0.001 to about 1 weight percent of silane materials.
8. A method for olefin polymerization which is conducted by contacting a catalyst system comprising
(a) a catalyst for olefin polymerization encapsulated with macromolecular monomers around the catalyst which is producted by treating the surface of a solid titanium catalyst for olefin polymerization with silane compounds leaving two or more vinyl groups and then prepolymerizing said surface treated solid titanium catalyst with olefin monomers and diene compounds,
(b) an organometallic compound of Group I or III metals of the Periodic Table and
(c) external electron donors with
(d) an α-olefin.
9. The method of claim 8 , wherein said organometallic compound of the (h) component is trialkylaluminium.
10. The method of claim 8 , wherein said external electron donors is an alkoxysilane compound.
11. The method of claim 8 , wherein said solid titanium catalyst is produced by (i) preparing magnesium compound solutions by dissolving magnesium compounds having no reducibility in electron donors, (ii) reacting said magnesium compound solutions with transition compounds, silicon compounds, tin compounds or a mixture thereof and precipitating solid particles and then (iii) reacting said precipitated solid particles with titanium compounds and electron donors.
12. The method of claim 8 , wherein said silane compound having two or more vinyl groups is divinyldimethylsilane, divinyldiphenylsilane, divinyldiethylsilane, divinyldiisobutylsilane or divinyldihydridesilane.
13. The method of claim 8 , wherein the amount of said silane compounds having two or more vinyl groups used is 2 to 200 moles per 1 mole of magnesium compound.
14. The method of claim 8 , wherein said olefin monomer is more than one monomer selected from the groups consisting of ethylene, propylene, 1-butene, 1-hexene, and 1-octene.
15. The method of claim 8 , wherein said diene compound is 1,3-butadiene, 1,5-hexadiene, 1,7-octadiene, 1,9-decadiene or 1,13-tetradecadiene.
16. The method of claim 8 , wherein said macromolecular monomers encapsulating around the catalyst have a molecular weight in the range of 500 to about 100,000, and is composed of 1 to about 99 weight percent of olefin 0.01 to about 10 weight percent of diene, and 0.001 to about 1 weight percent of silane materials.