Exxon Chemical Patents, Inc.

The Dow Chemical Company

Exxonmobil Chemical Patents Inc.

Exxon Research and Engineering Company

Jean M Tancrede

Charles F Diehl

Kenneth Lewtas

David John Lohse

Anthony George Karandinos

Keith A Nelson

Olivier J F Georjon

Michael O Myers

Sudhin Datta

Charles C Cozewith

Bruce Alan Harrington

Gary R Marchand

Bruce Allan Harrington

Anthony Jay Dias

George Rodriguez

David Raymond Johnsrud

Joseph Dominic Domine

Anthony J Berejka

Kenneth O McElrath

Fran A Shipley

Christopher Lewis Curry

Man-Fu Tse

Sally Q Pugh

Olivier J Georjon

Provided are adhesive compositions composed of a polyolefin composition comprising at least about 50 wt. % polypropylene and at least one wax. The polymer compositions have a Dot T-Peel of about 1 Newton or more, a branching index (g') of 0.95 or less measured at the Mz of the polymer, a molecular weight of 100,000 or less, and the adhesive compositions has a fast set time. The packaging industry desires adhesive compositions having a fast set time, such as those setting in less than five seconds from a molten state at conventional packaging operating temperatures to a solid or quasi solid having favorable Dot T-Peel, set time, and or fiber tear adhesion properties. Polymer based adhesives performing within this window are a favorable alternative to conventional formulated adhesives. The provided adhesive compositions exhibit a favorable balance of properties such as high adhesive strength, wide temperature operating window, and fast set time.

Polyolefin adhesive compositions and articles made therefrom

An adhesive blend is described that can include a semi-crystalline copolymer of propylene and at least one comonomer selected from the group consisting of ethylene and at least one Cto C&#x3b1;-olefin, the copolymer having a weight average molecular weight (Mw) from about 15,000 to about 200,000; an melt index (MI) from about 7 dg/min to about 3000 dg/min as measured by ASTM D 1238 (B), and a (Mw/Mn) of approximately 2. Various production processes are also described. Also described are adhesive compositions and methods for making adhesive compositions having polymers or polymer blends with melt flow rates (MFRS) equal to and above 250 dg/min. at 230&#xb0;C. Certain specific embodiments of the invention involve the use of a free radical initiator, e.g., a peroxide.

Polypropylene-based adhesive compositions

An adhesive blend is described that can include a semi-crystalline copolymer of propylene and at least one comonomer selected from the group consisting of ethylene and at least one Cto C&#x3b1;-olefin, the copolymer having a weight average molecular weight (Mw) from about 15,000 to about 200,000; an melt index (MI) from about 7 dg/min to about 3000 dg/min as measured by ASTM D 1238(B), and a (Mw/Mn) of approximately 2. Various production processes are also described. Also described are adhesive compositions and methods for making adhesive compositions having polymers or polymer blends with melt flow rates (MFRs) equal to and above 250 dg/min. at 230&#xb0; C. Certain specific embodiments of the invention involve the use of a free radical initiator, e.g., a peroxide.

The invention relates to novel adhesive alpha-olefin inter-polymers which are largely amorphous and have a rheological behavior that makes them suitable for adhesive use, both without and with minimzed amounts of tackifying resins. Specifically, the invention poly-alpha olefin inter-polymer may be composed of A) from 60 to 94% of units derived from one alpha mono-olefin having from 3 to 6 carbon atoms and B) from 6 to 40 mol % of units derived from one or more other mono-olefins having from 4 to 10 carbon atoms and at least one carbon atom more than A); and C) optionally from 0 to 10 mol % of units derived from another copolymerizable unsaturated hydrocarbon, different from A) and B); the diad distribution of component A in the polymer as determined byC NMR as described herein showing a ratio of experimentally determined diad distribution over the calculated Bernoullian diad distribution of less than 1.07; and the storage modulus G' of said polymer, determined upon cooling as described herein, intersecting a value of 3.10Pa at a temperature of less than 85&#xb0; C. The invention also describes polymerization processes suitable for the manufacture of these adhesive alpha-olefin inter-polymers.

Adhesive alpha-olefin inter-polymers

The invention provides a hot melt adhesive composition including a tubular reactor copolymer of ethylene and 5 to 20 mol % of comonomer units derived from an alkyl acrylate or alkyl methacrylate, wherein the copolymer has a melt index of at least 300 g/10 min. The alkyl group of the alkyl acrylate or alkyl methacrylate can be a linear or branched Cto Cgroup, particularly n-butyl. If desired, the hot melt adhesive can further include tackifiers, waxes, antioxidants and other desired additives. The hot melt adhesive composition shows improved heat resistance and favorable properties, such as has a shear adhesion fail temperature of at least 80&#xb0; C., without the need to use high melting waxes. The invention further provides articles such as cartons, cases, trays, bookbindings or disposables including the hot melt adhesive compositions.

Hot melt adhesives

An adhesive blend is described that can include a semi-crystalline copolymer of propylene and at least one comonomer selected from the group consisting of ethylene and at least one C to C &agr;-olefin, the copolymer having a weight average molecular weight (Mw) from about 15,000 to about 200,000; an melt index (MI) from about 7 dg/min to about 3000 dg/min as measured by ASTM D 1238(B), and a (Mw/Mn) of approximately 2. Various production processes are also described. Also described are adhesive compositions and methods for making adhesive compositions having polymers or polymer blends with melt flow rates (MFRs) equal to and above 250&deg; dg/min. at 230&deg; C. Certain specific embodiments of the invention involve the use of a free radical initiator, e.g., a peroxide.

The invention relates to novel adhesive alpha-olefin inter-polymers which are largely amorphous and have a rheological behavior that makes them suitable for adhesive use, both without and with minimized amounts of tackifying resins. Specifically, the invention poly-alpha olefin inter-polymer may be composed of A) from 60 to 94 mol % of units derived from one alpha mono-olefin having from 3 to 6 carbon atoms and B) from 6 to 40 mol % of units derived from one or more other mono-olefins having from 4 to 10 carbon atoms and at least one carbon atom more than A); and C) optionally from 0 to 10 mol % of units derived from another copolymerizable unsaturated hydrocarbon, different from A) and B); the diad distribution of component A in the polymer as determined by C NMR as described herein showing a ratio of experimentally determined diad distribution over the calculated Bernoullian diad distribution of less than 1.07; and the storage modulus G&prime; of said polymer, determined upon cooling as described herein, intersecting a value of 3.10 Pa at a temperature of less than 85&deg; C. The invention also describes polymerization processes suitable for the manufacture of these adhesive alpha-olefin inter-polymers.

Hot-melt adhesive compositions containing high molecular weight linear styrene-isoprene-styrene block copolymers or high molecular weight linear styrene-butadiene-styrene copolymers, having little or no residual diblock, and articles made therefrom. The resulting adhesive composition may include solid tackifying and liquid tackifying resins.

Hot-melt adhesives for disposable items and articles made therefrom

The invention is drawn to radial block copolymers of the formula:

Radial styrene-isoprene-butadiene multi-armed block copolymers and

Radial block copolymers characterized by the formulas: (1) (pS-pI).sub.n X and (2) (pS-pI-pB).sub.n X where pS is polystyrene, pI is polyisoprene, pB is butadiene, X is a residue of a multifunctional coupling agent used in the production of the radial block copolymer, and n is a number greater than 2 representative of the number of branches appended to X; hot-melt adhesive compositions constituted of said radial block copolymers, and articles of manufacture produced therefrom. These copolymers possess blocks of high average molecular weight polystyrene (10,000 to 25,000) and an overall average molecular weight (90,000 to 380,000) such that when blended in requisite proportions with a compatible tackifier resin, preferably also a secondary tackifying resin or plasticizing oil, and stabilizer, superior hot-melt adhesive compositions can be formed. The hot-melt adhesive compositions possess, inter alia, superior heat resistance, superior static time to failure with low viscosity, good peel adhesion, good tack, and high ability to bond to a polyethylene or polypropylene substrate at temperatures below that which may damage the substrate.

Adhesive compositions containing radial block copolymers with butadiene

Blends of low styrene content polystyrene-polyisoprene-polystyrene block copolymer and high styrene content polystyrene-polyisoprene-polystyrene block copolymer can be used with tackifier resins, plasticizer oil and antioxidants to formulate pressure sensitive adhesives of improved cohesive strength vis-a-vis adhesives formed from the low styrene content polystyrene-polyisoprene-polystyrene block copolymer while maintaining good balance between tack, bonding characteristics and heat resistance.

Blends containing polystyrene-polyisoprene-polystyrene block copolymers

Compositions containing blends of polystyrene-polyisoprene-polystyrene

Radial block copolymers containing butadiene endblock

Polystyrene-polyisoprene-polystyrene block copolymers, hot-melt adhesive compositions constituted of polystyrene-polyisoprene-polystyrene block copolymers, and articles of manufacture produced therefrom. These copolymers possess blocks of high average molecular weight polystyrene (12,000 to 20,000) and low overall average molecular weight (60,000 to 110,000) such that when blended in requisite proportions with a compatible tackifier resin, preferably also a secondary tackifying resin or plasticizing oil, and stabilizer, superior hot-melt adhesive compositions can be formed. The hot-melt adhesive compositions possess, inter alia, superior heat resistance, superior static time to failure with low viscosity, good peel adhesion, good tack, and high ability to bond to a polyethylene or polypropylene substrate at temperatures below that which may damage the substrate.

Disposable articles of manufacture containing

An adhesive is disclosed. The adhesive is a blend of a tackifier and a polymer, having an elastomeric main chain and incorporating thermoplastic macromonomer side chain grafts, which can exhibit enhanced shear thinning and allow spray application of the adhesive onto a substrate. In one embodiment, the polymer main chain comprises a polymer of an isoolefin having about 4 to about 7 carbon atoms and a para-alkylstyrene, and the side chains comprise a grafted macromonomer, such as a terminally functionalized polystyryl chain of very narrow molecular weight distribution, attached to the para-alkyl group of the para-alkylstyrene. In another embodiment, the polymer comprises a polyolefin main chain and a norbornene terminated macromolecule copolymerized to introduce the side chains.

Growing community of inventors

Baton Rouge, LA, United States of America

Jean M Tancrede