The Dow Chemical Company

Dow Global Technolgoies LLC

George W. Knight

Marvin A. White

Lawrence H. Sawyer

Ronald P. Markovich

Shih-yaw Lai

Pak Wing Steve Chum

Rexford A. Maugans

Edward N. Knickerbocker

George W Knight

Shih-Yaw Lai

James C Stevens

John R Wilson

Pak-Wing Steve Chum

Lawrence H Sawyer

Chung P Park

Rexford Allison Maugans

Edward N Knickerbocker

Ronald P Markovich

Rajen M Patel

Thoi H Ho

Martin J Guest

Deepak R Parikh

Stephen R Betso

Kirby Lowery, Jr

Antonio Batistini

James A May, Jr

Marvin A White

Wasif K Ahmed

Morris S Edmondson

James A Allen

Donald F Birkelbach

Dennis E Mach

Gregory L Dohrer

Substantially linear olefin polymers having a melt flow ratio, I/I,&#x2267;5.63, a molecular weight distribution, M/M, defined by the equation: M/M&#x2266;(I/I)&#x2212;4.63, and a critical shear stress at onset of gross melt fracture of greater than about 4&#xd7;10dyne/cmand their method of manufacture are disclosed. The substantially linear olefin polymers preferably have at least about 0.01 long chain branches/1000 carbons and a molecular weight distribution from about 1.5 to about 2.5. The new polymers have improved processability over conventional olefin polymers and are useful in producing fabricated articles such as fibers, films, and molded parts.

Elastic substantially linear olefin polymers

Elastic ethylene polymers are disclosed which have processability similar to highly branched low density polyethylene (LDPE), but the strength and toughness of linear low density polyethylene (LLDPE). The polymers have processing indices (PI's) less than or equal to 70 percent of those of a comparative linear ethylene polymer and a critical shear rate at onset of surface melt fracture of at least 50 percent greater than the critical shear rate at the onset of surface melt fracture of a traditional linear ethylene polymer at about the same I and M /M . The novel polymers can also have from about 0.01 to about 3 long chain branches/1000 total carbons and have higher low/zero shear viscosity and lower high shear viscosity than comparative liner ethylene polymers. The novel polymers can also be characterized as having a melt flow ratio, I /I , &gE;5.63, a molecular weight distribution, M /M , defined by the equation: M /M &lE;(I /I )&minus;4.63, a critical shear stress at onset of gross melt fracture greater than about 4&times;10 dyne/cm , and a single DSC melt peak between &minus;30 C and 150 C.

Elastic substantially linear ethylene polymers

Substantially linear olefin polymers having a melt flow ratio, I /I , &gE;5.63, a molecular weight distribution, M /M , defined by the equation: M /M &lE;(I /I )&minus;4.63, and a critical shear stress at onset of gross melt fracture of greater than about 4&times;10 dyne/cm and their method of manufacture are disclosed. The substantially linear olefin polymers preferably have at least about 0.01 long chain branches/1000 carbons and a molecular weight distribution from about 1.5 to about 2.5. The new polymers have improved processability over conventional olefin polymers and are useful in producing fabricated articles such as fibers, films, and molded parts.

Elastic ethylene polymers are disclosed which have processability similar to highly branched low density polyethylene (LDPE), but the strength and toughness of linear low density polyethylene (LDPE). The polymers have processing indices (PI's) less than or equal to 70 percent of those of a comparative linear ethylene polymer and a critical shear rate at onset of surface melt fracture of at least 50 percent greater than the critical shear rate at the onset of surface melt fracture of a traditional linear ethylene polymer at about the same I and M /M . The novel polymers can also have from about 0.01 to about 3 long chain branches/1000 total carbons and have higher low/zero shear viscosity and lower high shear viscosity than comparative linear ethylene polymers. The novel polymers can also be characterized as having a melt flow ratio, I /I , &gE;5.63, a molecular weight distribution, M /M , defined by the equation: M /M &lE;(I /I )&minus;4.63, a critical shear stress at onset of gross melt fracture greater than about 4&times;10 dyne/cm , and a single DSC melt peak between &minus;30 C and 150 C.

Elastic ethylene polymers are disclosed which have processability similar to highly branched low density polyethylene (LDPE), but the strength and toughness of linear low density polyethylene (LLDPE). The polymers have processing indices (PI's) less than or equal to 70 percent of those of a comparative linear ethylene polymer and a critical shear rate at onset of surface melt fracture of at least 50 percent greater than the critical shear rate at the onset of surface melt fracture of a traditional linear ethylene polymer at about the same I and M /M . The novel polymers can also have from about 0.01 to about 3 long chain branches/1000 total carbons and have higher low/zero shear viscosity and lower high shear viscosity than comparative linear ethylene polymers. The novel polymers can also be characterized as having a melt flow ratio, I /I , &gE;5.63, a molecular weight distribution, M /M , defined by the equation: M /M &lE;(I /I )&minus;4.63, a critical shear stress at onset of gross melt fracture greater than about 4&times;10 dyne/cm , and a single DSC melt peak between &minus;30 C. and 150 C.

Elastic fibers and fabrics made from homogeneously branched substantially linear ethylene polymers are disclosed which can be produced on conventional polypropylene or polyethylene fiber or fabric processes. They can be used to produce highly elastic structures that can have recycle compatibility between elastic and non-elastic components. The novel fibers have at least about 50% recovery at 100% strain. The fibers and fabrics are especially useful in making fabricated articles and components thereof (e.g., disposable diapers).

Elastic fibers, fabrics and articles fabricated therefrom

Block copolymer compositions containing substantially inert thermoelastic extenders

The present invention pertains to a substantially linear olefin polymer which has long chain branches, a high melt flow ratio, a narrow molecular weight distribution and critical shear rate at onset of surface melt fracture of a least 50 percent greater than the critical shear rate at the onset of melt fracture which is substantially higher than that of a linear olefin polymer having about the same molecular weight and molecular weight distribution. The novel polymer is an interpolymer of ethylene with at least one C -C alpha-olefin and at least one unsaturated monomer.

Fibers made from formulated ethylene polymer compositions are disclosed. The ethylene polymer compositions have at least one homogeneously branched linear ethylene/&agr;-olefin interpolymer and at least one heterogeneously branched ethylene polymer. The homogeneously branched linear ethylene/&agr;-olefin interpolymer has a density from about 0.905 to about 0.92 g/cm3 and a slope of strain hardening coefficient greater than or equal to about 1.3.

Ethylene polymer fiber made from ethylene polymer blends

Elastic fibers and fabrics made from homogeneously branched linear ethylene polymers are disclosed. The elastic fibers and fabrics can be used to produce structures that can have recycle compatibility between elastic and non elastic components. The novel fibers have at least about 50% recovery at 100% strain. The fibers and fabrics are especially useful in making fabricated articles and components thereof (e.g., disposable diapers).

Fabrics fabricated from elastic fibers

Elastic fibers

Growing community of inventors

Lake Jackson, TX, United States of America

George W Knight