摘要:
Method of improving the crystallization rate and temperature of syndiotactic polypropylene by addition of at least one of polytetrafluoroethylene, sodium 2,2-methylene-bis-(4,6,di-tert-butylphenyl)phosphate)), pimellic acid, and calcium pimallate, and compositions and products made thereby.
摘要:
Provided is process of polymerizing monomer having at least one Ziegler-Natta polymerizable bond, comprising contacting monomer with, reacting monomer in presence of, or combinations thereof, catalyst system comprising:
A) catalyst component consisting essentially of
i) about 1.5 weight % to about 6 weight % titanium, ii) about 10 weight % to about 20 weight % magnesium, iii) about 40 weight % to about 70 weight % halogen, iv) about 5 weight % to about 25 weight % polycarboxylic ester selected from the group consisting of esters aliphatic, aromatic, alicyclic polycarboxylic acids, or combinations thereof or alkyl phthalates, and v) about 0.1 weight percent to about 2.5 weight % organic phosphorous compound selected from the group consisting of hydrocarbon esters of phosphoric acid such that each hydrocarbon group has one to about six carbon atoms;
B) electron donor described by the formula: wherein R 1 is alkyl or cycloakylgroup containing at least one secondary or tertiary carbon atom, R 2 and R 3 are each independently alkyl or aryl group, and R 4 is an alkyl group having a primary carbon bonded to the silicon atom; and C) organic aluminum compound.
摘要:
Provided is polyolefin composition, the majority of which is highly isotactic polypropylene, comprising the property of heat of melting (ΔH m ) greater than or equal to about 89 J/g.
摘要:
The present invention provides a catalyst system that exhibits control of desired properties in the polymer product. The catalyst system includes a conventional supported Ziegler-Natta catalyst containing an organic phosphorus compound in combination with an electron donor having the general formula SiR m (OR') 4-m where R is selected from the group consisting of an alkyl group, a cycloalkyl group, an aryl group and a vinyl group; R' is an alkyl group; and m is 0-3, wherein when R is an alkyl group, R may be identical with R'; when m is 0, 1 or 2, the R' groups may be identical or different; and when m is 1, 2 or 3, the R groups may be identical or different. The system easily achieves efficiencies over 30 kg/g-cat·h. The system also exhibits good control over the xylene solubles of the polymer products and produces a highly crystalline polymer product. The electron donor is preferably described by the formula: wherein R 1 is an alkyl or cycloalkyl group containing a primary, secondary or tertiary carbon atom attached to the silicon atom; R 2 and R 3 are alkyl or aryl groups; and R 4 is an alkyl or cycloalkyl group with a secondary or tertiary carbon atom attached to the silicon atom. More preferably, R 1 and R 4 are both cycloalkyl groups and are both the same. Most preferably, R 1 and R 4 are both cyclopentyl groups and R 2 and R 3 are both methoxy groups. Specifically, the electron donor may be dicyclopentyldimethoxysilane.
摘要:
A polyolefin metallocene catalyst which includes two metallocene components, a stereorigid isospecific metallocene catalyst component and a stereorigid syndiospecific metallocene catalyst component, both of which are supported upon the same support. A method of forming a catalyst system includes contacting the above catalyst with a cocatalyst or Lewis acid. A method of polymerization includes contacting an olefin with the catalyst system.
摘要:
The present invention provides a catalyst system that exhibits control of desired properties in the polymer product. The catalyst system includes a conventional supported Ziegler-Natta catalyst containing an organic phosphorus compound in combination with an electron donor having the general formula SiR m (OR') 4-m where R is selected from the group consisting of an alkyl group, a cycloalkyl group, an aryl group and a vinyl group; R' is an alkyl group; and m is 0-3, wherein when R is an alkyl group, R may be identical with R'; when m is 0, 1 or 2, the R' groups may be identical or different; and when m is 1, 2 or 3, the R groups may be identical or different. The system easily achieves efficiencies over 30 kg/g-cat·h. The system also exhibits good control over the xylene solubles of the polymer products and produces a highly crystalline polymer product. The electron donor is preferably described by the formula: wherein R 1 is an alkyl or cycloalkyl group containing a primary, secondary or tertiary carbon atom attached to the silicon atom; R 2 and R 3 are alkyl or aryl groups; and R 4 is an alkyl or cycloalkyl group with a secondary or tertiary carbon atom attached to the silicon atom. More preferably, R 1 and R 4 are both cycloalkyl groups and are both the same. Most preferably, R 1 and R 4 are both cyclopentyl groups and R 2 and R 3 are both methoxy groups. Specifically, the electron donor may be dicyclopentyldimethoxysilane.
摘要:
A composition and process for making it are disclosed which teach multimodal particle size high impact monovinylaromatic polymer material having good gloss properties as well as high impact strength. The bimodal particle size rubber component of the material utilizes a small amount of a very large particle size rubber and a large amount of a very small particle size rubber. The unique and advantageous method of manufacturing the material involves introducing pre-existing pellets of a rubber/polymer blend into a monomer solution also containing a rubber capable of producing particles of a different range of sizes than that of the rubber component in the pellets, and polymerizing the monomer/dissolved pellet mixture into a multimodal particle size high impact material.