摘要:
The present invention relates to a method of preparing adhesive coated articles and cold seal bonded laminates therefrom. Specifically, it relates to a method wherein certain polychloroprene based adhesive compositions are used to form adhesive coated substrates that are non-blocking and pressure sealable at ambient temperature. In a preferred embodiment, the invention relates to a method for the preparation of coated substrates and articles that are particularly useful for the manufacture of medical packaging and tamper evident applications.
摘要:
The present invention discloses a stable aqueous polyurethane dispersions comprising a reaction product of a water dispersible isocyanate-terminated polyurethane prepolymer (A), an aqueous polyurethane dispersion (B) and water, and a method wherein a water dispersible isocyanate-terminated polyurethane prepolymer (A) is dispersed in at least one aqueous polyurethane dispersion (B) and water, and reacted at about 35.degree. C. to about 95.degree. C. until substantially free of isocyanate. The inventive dispersions are useful in adhesives, coatings, binders, primers and sizers.
摘要:
The present invention is directed to aqueous polyurethane dispersions and aqueous polyurethane-acrylic dispersions, especially polymer dispersions formed from norbornane diisocyanate. The dispersions, and the dried polymers therefrom, are useful adhesives that provide enhanced bond strength when subjected to increased thermal and mechanical stress. Additionally, the inventive dispersions form polymers having increased adhesion compared to similar polymers based on cycloaliphatic diisocyanates which are free of a methylene bridge.
摘要:
A method of bonding two substrates at least one of which is a rubbery polymeric material having carbon-carbon double bonds on the polymer backbone, the method comprising: a) applying an aqueous polyurethane dispersion adhesive composition to at least one of the substrates, the adhesive compostion further comprising an epoxy resin; b) allowing the composition to dry; and then c) joining the substrates with heating to activate the adhesive. The substrates are suitably footwear materials such as a molded rubber outer sole which has been first primed with a chlorinating primer, and a foam midsole of a material such as a lightly crosslinked ethylene vinyl acetate. The process results in bonded assemblies having improved humidity resistance.
摘要:
A method for the preparation of sulfonated polymer compositions wherein water dispersible isocyanate-terminated polyurethane prepolymers are reacted in the presence of aqueous polyvinyl dispersions which may contain active hydrogen atoms. The invention is further directed to a water-based sulfonated polyurethane polyvinyl hybrid latex wherein a sulfonated polyurethane is used as a seed for the polymerization of ethylenically unsaturated monomers and a method for preparing the same. The inventive compositions develop interpenetrating polymer networks or may form core-shell type structures, and are characterized as having enhanced mechanical and adhesion properties.
摘要:
A moisture curable acrylic formulation is provided inclusive of a majority by weight polyacrylic prepolymer. The prepolymer has an average molecular weight of between 3,000 and 6,000 grams per mole and between 2 and 4 moisture curable functional moieties of isocyanate or silane per prepolymer. A thermoplastic adhesive resin is also included within the formulation. When the prepolymer functional moieties are all silane, the thermoplastic adhesive resin is ethylene vinyl acetate resin. A silane molecule is provided within the formulation as an adhesion promoter and also affords a degree of storage stability through sacrificial reaction with water during storage. The resultant formulation achieves a shear strength of at least 10 pounds per square inch when applied to a thickness of 0.75 millimeters between a glass substrate and a vinyl article 15 minutes after application at 120° Celsius in ambient atmospheric air. The formulation is well suited for the formation of a window assembly when applied intermediate between a substrate and a window article.
摘要:
A moisture curable acrylic formulation is provided inclusive of a majority by weight polyacrylic prepolymer. The prepolymer has an average molecular weight of between 3,000 and 6,000 grams per mole and between 2 and 4 moisture curable functional moieties of isocyanate or silane per prepolymer. A thermoplastic adhesive resin is also included within the formulation. When the prepolymer functional moieties are all silane, the thermoplastic adhesive resin is ethylene vinyl acetate resin. A silane molecule is provided within the formulation as an adhesion promoter and also affords a degree of storage stability through sacrificial reaction with water during storage. The resultant formulation achieves a shear strength of at least 10 pounds per square inch when applied to a thickness of 0.75 millimeters between a glass substrate and a vinyl article 15 minutes after application at 120° Celsius in ambient atmospheric air. The formulation is well suited for the formation of a window assembly when applied intermediate between a substrate and a window article.
摘要:
A method for the preparation of sulfonated polymer compositions wherein water dispersible isocyanate-terminated polyurethane prepolymers are reacted in the presence of aqueous polyvinyl dispersions which may contain active hydrogen atoms. The inventive compositions develop interpenetrating polymer networks, which may form core-shell type structures, and are characterized as having enhanced mechanical and adhesion properties.
摘要:
A polyacrylic polymer is provided that is formed by moisture cure of multiple acrylic prepolymer segments. The prepolymer segments each have an average molecular weight of between 5000 and 400,000 grams per mole. Each of the prepolymers is a homopolymer or copolymer of a monomer from among methyl methacrylate, C1-C16 alkyl acrylate, and C1-C16 alkyl methyl methacrylate as the predominant monomeric group. The prepolymers are interconnected through moisture cure induced urea, urethane, or combinations thereof. The polymer is readily cured upon exposure to atmospheric moisture absent inclusion or evolution of a volatile organic compound. The polymer is likewise formed HAP free. Through control of prepolymer properties a variety of thermoset polymer properties are obtained. A prepolymer is formed including a minority amount of functionalized acrylic monomer that is isocyanate or converted to isocyanate through subsequent reaction. Functionalized acrylic monomers operative herein include a hydroxyl, a primary amine, a secondary amine, a sulfonic acid, or an epoxy. Upon application from storage in an anhydrous state, the prepolymer cures upon exposure to atmospheric moisture.
摘要:
The present invention provides improved compositions and methods for producing moisture-cured adhesives and sealants based on modified silicone polymers. Methods of the present invention do not require a discrete step to dry the fillers that are incorporated into the materials and produce products with an excellent shelf life.