4677 results about "Alpha-olefin" patented technology

This invention relates to polyolefin compositions. In particular, the invention pertains to elastic polymer compositions that can be more easily processed on cast film lines, extrusion lamination or coating lines due to improved resistance to draw resonance. The compositions of the present invention preferably comprise an elastomeric polyolefin resin and a high pressure low density type resin.

Embodiments of the invention provide a class of ethylene / α-olefin block interpolymers. The ethylene / α-olefin interpolymers are characterized by an average block index, ABI, which is greater than zero and up to about 1.0 and a molecular weight distribution, Mw / Mn, greater than about 1.3. Preferably, the block index is from about 0.2 to about 1. In addition or alternatively, the block ethylene / α-olefin interpolymer is characterized by having at least one fraction obtained by Temperature Rising Elution Fractionation (‘TREF’), wherein the fraction has a block index greater than about 0.3 and up to about 1.0 and the ethylene / α-olefin interpolymer has a molecular weight distribution, Mw / Mn, greater than about 1.4.

The present invention is a, solid block copolymer comprising at least two polymer end blocks A and at least one polymer interior block B wherein each A block is a polymer block resistant to sulfonation and each B block is a polymer block susceptible to sulfonation, and wherein said A and B blocks do not contain any significant levels of olefinic unsaturation. Preferably, each A block comprising one or more segments selected from polymerized (i) para-substituted styrene monomers, (ii) ethylene, (iii) alpha olefins of 3 to 18 carbon atoms; (iv) hydrogenated 1,3-cyclodiene monomers, (v) hydrogenated monomers of conjugated dienes having a vinyl content less than 35 mol percent prior to hydrogenation, (vi) acrylic esters, (vii) methacrylic esters, and (viii) mixtures thereof; and each B block comprising segments of one or more polymerized vinyl aromatic monomers selected from (i) unsubstituted styrene monomers, (ii) ortho-substituted styrene monomers, (iii) meta-substituted styrene monomers, (iv) alpha-methylstyrene, (v) 1,1-diphenylethylene, (vi) 1,2-diphenylethylene and (vii) mixtures thereof. Also claimed are processes for making such block copolymers, and the various end uses and applications for such block copolymers.

This invention relates generally to low ethylene insertions into I-olefin polymers and processes for production of such polymers using unbridged fluxional metallocenes, primarily substituted aryl indenyl metallocenes, and more particularly to use of unbridged, fluxional, cyclopentadienyl or indenyl metallocene catalyst systems in methods of production of high melting point I-olefin homo- and co-polymers, particularly elastomeric crystalline and amorphous block homo- and co-polymers of I-olefins. The activity of fluxional unbridged metallocene polymerization catalysts containing at least one 2-arylindene ligand is increased 10x or more by the addition of small (typically 0.1-10 wt. %) amounts of ethylene to the polymerization system, which increase is termed the Polymerization Rate-Enhancement effect (PRE), which is measured in terms of an Ethylene Enhancement Factor (EEF) as a dimensionless ratio in the range of from about 1.1 to about 10 or above. The amount of ethylene included in the reaction system can be selected and controlled to be so small as to result in essentially minimal (<2 mole %) incorporation of ethylene units into the resulting elastomeric polymer and the molecular weight may be increased. Amounts of ethylene to generate the PRE effect may be greater than 0.1 wt. % and preferably range up to about 2 wt. %. However, if a polymer with more ethylene is desired, additional ethylene may be incorporated into the polymerization feed, including up to 10 to about 50 mole % based on olefin units. A second important aspect of this invention is the ability to use a PRE activity-enhancing amount of ethylene in an olefin polymerization without substantially affecting the physical properties of the elastomer. In a third important aspect of this invention, I-olefin elastomers are produced through incorporation of ethylene using unbridged fluxional catalyst systems which may not otherwise produce acceptable elastomeric homopolymers. This effect is termed the EPE effect, for Elastomeric Property-Enhancing effect. The EPE amount of ethylene required to produce such elastomers typically overlaps the PRE activity-enhancing amount. Incorporation of up to about 5 mole % or more of ethylene typically will produce an elastomeric polymer using such catalyst systems. Typical useful amounts of incorporated ethylene include about 1 to 3 mole %. Preferred polymers of this invention retain sufficient crystallinity to provide a high melting point (by DSC) of about 80° C., preferably above 100° C., including in the range of from about 120° C. to about 140° C. and above. Novel flexible alpha-olefin homo and copolymers having elongation in excess of 600% and substantially no retained force are disclosed.

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.

The present invention relates to film layers and compositions having improved hot tack properties. The compositions comprise at least one ethylene / α-olefin interpolymer, wherein the ethylene / α-olefin interpolymer may have, for example, a Mw / Mn from about 1.7 to about 3.5, at least one melting point, Tm, in degrees Celsius, and a density, d, in grams / cubic centimeter, wherein the numerical values of Tm and d correspond to the relationship:Tm>−2002.9+4538.5(d)−2422.2(d)2.

Improved thermoplastic polymer blend compositions comprising an isotactic polypropylene component and an alpha-olefin and propylene copolymer component, said copolymer comprising crystallizable alpha-olefin sequences. In a preferred embodiment, improved thermoplastic polymer blends are provided comprising from about 35% to about 85% isotactic polypropylene and from about 30% to about 70% of an ethylene and propylene copolymer, wherein said copolymer comprises isotactically crystallizable propylene sequences and is predominately propylene. The resultant blends manifest unexpected compatibility characteristics, increased tensile strength, and improved process characteristics, e.g., a single melting point.