376 results about "Multiblock copolymer" patented technology

A composition for use in forming a multi-block copolymer, said copolymer containing therein two or more segments or blocks differing in chemical or physical properties, a polymerization process using the same, and the resulting polymers, wherein the composition comprises the admixture or reaction product resulting from combining: (A) a first metal complex olefin polymerization catalyst, (B) a second metal complex olefin polymerization catalyst capable of preparing polymers differing in chemical or physical properties from the polymer prepared by catalyst (A) under equivalent polymerization conditions, and (C) a chain shuttling agent.

Anti-blocking polymer compositions comprise at least one ethylene / α-olefin interpolymer and at least one anti-blocking agent comprising an amide. The ethylene / α-olefin interpolymers are a multi-block copolymer comprising at least one soft block and at least one hard block. The anti-blocking agent can be erucamide or other amides. The anti-blocking polymer composition has a pellet blocking strength of equal to or less than 100 lbs / ft2 (4800 Pa). When the anti-blocking polymer composition is made into a film, the film has a blocking force of less than about 100 grams, measured according to ASTM method D-3354.

This invention relates to high melting polyolefin copolymers suitable as thermoplastic elastomers and catalysts and methods for their synthesis. These elastomeric olefin copolymers are characterized by a mole fraction of crystallizable component Xc from about 30 to about 99%; low glass transition temperatures, below -20° C., and typically below -50° C.; melting points above about 90° C.; high molecular weights; a molecular weight distribution MW / Mn< / =10; and a narrow composition distribution between chains of < / =15%. The novel copolymers of the invention range from reactor blends to multiblock copolymers that can be sequentially fractionated into fractions of differing crystallinities, which fractions nevertheless show compositions of comonomers which differ by less than 15% from the parent polymer (reactor product). The invention also relates to a process for producing such copolymers by utilizing an unbridged, substituted or unsubstituted cyclopentadienyl metallocene catalyst that is capable of interconverting between states with different copolymerization characteristics, which interconversion is controlled by selecting the substituents of the cyclopentadienyl ligands so that the rate of interconversion of the two states is within several orders of magnitude of the rate of formation of a single polymer chain. Where ri>rf the polymer can be characterized as multiblock; where ri<rf, the result is a polymer blend and where ri / rf is close to 1, the resulting polymer is a mixture of blend and multiblock. The metallocene catalysts of the invention are able to interconvert between more than two states, with embodiments of four states being shown in FIG. 2.

Copolymers, especially multi-block copolymer containing therein two or more segments or blocks differing in chemical or physical properties, are prepared by polymerizing propylene, 4-methyl-1-pentene, or other C4-8α-olefin and one or more copolymerizable comonomers, especially ethylene in the presence of a composition comprising the admixture or reaction product resulting from combining: (A) a first metal complex olefin polymerization catalyst, (B) a second metal complex olefin polymerization catalyst capable of preparing polymers differing in chemical or physical properties from the polymer prepared by catalyst (A) under equivalent polymerization conditions, and (C) a chain shuttling agent.

The present invention relates to the field of polymer chemistry and more particularly to multiblock copolymers and micelles comprising the same.

Foamable compositions and foams comprise at least an ethylene / α-olefin interpolymer. The foam has a density from greater than 150 to about 500 kg / m3. The foamable compositions further comprise a blowing agent and a crosslinking agent. The ethylene / α-olefin interpolymers are a multi-block copolymer comprising at least one soft block and at least one hard block. Methods of making the foamable compositions and foams; and foamed articles made from the foams are also described.

A composition for use in forming a multi-block copolymer from a single polymerizable monomer, said copolymer containing therein two or more segments or blocks differing in branching index, a polymerization process using the same, and the resulting polymers, wherein the composition comprises the admixture or reaction product resulting from combining: (A) a first olefin polymerization catalyst, (B) a second olefin polymerization catalyst capable of preparing polymers differing in chemical or physical properties from the polymer prepared by catalyst (A) under equivalent polymerization conditions, at least one of catalyst (A) or catalyst (B) being capable of forming a branched polymer by means of chain walking or reincorporation of in situ formed olefinic polymer chains, and (C) a chain shuttling agent.

A process for preparing polymers, especially multi-block copolymer containing therein two or more segments or blocks differing in chemical or physical properties, by contacting propylene, 4-methyl-1-pentene, or other C4-8 α-olefins and one or more copolymerizable comonomers, especially ethylene in the presence of a composition comprising the admixture or reaction product resulting from combining:(A) a first metal complex olefin polymerization catalyst,(B) a second metal complex olefin polymerization catalyst capable of preparing polymers differing in chemical or physical properties from the polymer prepared by catalyst (A) under equivalent polymerization conditions, and(C) a chain shuttling agent.