摘要:
This invention presents improved epoxy-based die attach adhesives which are of low viscosity, high ionic purity, and stable toward thermal cycling. This improvement is obtained by including in the formulation carboxy terminated polymers which are the reaction products of polyether diols with cyclic dianhydrides.
摘要:
This invention relates to pressure sensitive adhesives, and processes of preparing such adhesives, comprising random star polymers which are crosslinked by reaction with multifunctional crosslinking agent. These adhesives can be used in coated articles.
摘要:
A hot-melt adhesive especially useful in the construction of disposable diapers contains a vinyl polymer of 40-90% by weight of a C.sub.1 -C.sub.12 alkyl acrylate and 10-60% by weight of an alpha-olefin of C.sub.20 -C.sub.40, wherein the alkyl acrylate may be partially replaced with vinyl acetate or with a C.sub.6 -C.sub.12 olefin or with mixtures thereof, provided that the polymer contain at least 10% by weight of the alkyl acrylate. The adhesive may also contain a tackifying resin, a wax, an oil or a stabilizer depending on the specific end-use desired. In a preferred embodiment the polymer contains 20-45% by weight of the alpha-olefin.
摘要:
Adhesive compositions having enhanced bond strength are obtained by mixing a monomeric ester of 2-cyanoacrylic acid with an anionic polymerization inhibitor and from 1 to 30 mmoles per kg. of adhesive of an adhesion promoter of the formula: ##STR1## wherein R' is hydrogen or an alkyl, aryl or cycloalkyl group having 1-10 carbon atoms. Such compositions may be used on a wide variety of substrates and are particularly useful on metals.
摘要:
Novel polyimides, optionally end-capped with polymerizable or inert groups, and the polyamic acid or ester intermediates thereof are prepared by reacting a tetracarboxylic acid compound (e.g. pyromellitic dianhydride or 3,3',4,4'-benzophenone tetracarboxylic acid dianhydride or its methyl diester) with diamines having the general formula ##STR1## wherein Z is oxygen or sulfur, X and/or Y are carbonyl or carbinol groups, the amine groups may be in the 2-, 3-, and/or 4-position, and isomerism is present when X and/or Y is a carbinol group. The polyimides may be end-capped by reaction, during or after their formation, with polymerizable groups such as 3-aminophenyl acetylene or 3,6-endomethylene-1,2,3,6-tetrahydrophthalic anhydride. The diamines are novel classes of amines when Z is sulfur and when Z is oxygen and X, Y, or X and Y are carbinol groups.
摘要:
An adhesive composition based on 2-cyanoacrylate esters contains as an anionic polymerization inhibitor an acid chelate formed of boric acid or a derivative thereof and a selected polyhydroxy compound. The chelate is conveniently formed in situ in the 2-cyanoacrylate ester, but may also be prepared separately and added to the ester directly. An exemplary acid chelate used as stabilizer is prepared from boric acid and pyrogallol. The resulting stabilized adhesive compositions have a rapid cure rate and may be used on a wide variety of substrates.
摘要:
Polyamide graft-modified rubbery block copolymer compositions are provided by reaction of maleated rubbery block copolymers with polymeric dimer fatty acid based polyamide wherein the molar ratio of maleated rubbery block copolymer to the dimer fatty acid polyamide is greater than 2 to 1. The compositions find use as hot melt adhesive components.
摘要:
A process for preparing methyl .alpha.-cyanoacrylate in which methyl cyanoacetate is reacted with formaldehyde to form a polymer, which is subsequently depolymerized to the monomeric product, comprises using an ester of poly(ethylene glycol) as the solvent for the polymerization and depolymerization reactions.
摘要:
Hot melt adhesive compositions are prepared from 20 to 98% by weight of a polylactide homo- or copolymer containing at least 20 molar percent of the lactide component; 2 to 80% by weight of a polar tackifier having a Ring and Ball softening point (as described by ASTM E-26) greater than about 60.degree. C.; 0 to 50% by weight of a plasticizer; 0 to 30% by weight of a wax diluent; 0-3% by weight of a stabilizer; and 0-20% of starch. By utilizing a naturally occurring, thermoplastic, biodegradable copolymer as the base polymer, these adhesives advance the state of the art of hot melt adhesives by alleviating the dependence on petroleum based materials and by allowing for the development of hot melt adhesives which either degrade naturally after coming in contact with the soil or which can be composted.
摘要:
Novel polyimides, optionally end-capped with polymerizable or inert groups, and the polyamic acid or ester intermediates thereof are prepared by reacting a tetracarboxylic acid compound (e.g. pyromellitic dianhydride or 3,3',4,4'-benzophenone tetracarboxylic acid dianhydride or its methyl diester) with diamines having the general formula ##STR1## wherein Z is oxygen or sulfur, X and/or Y are carbonyl or carbinol groups, the amine groups may be in the 2-, 3-, and/or 4-position, and isomerism is present when X and/or Y is a carbinol group. The polyimides may be end-capped by reaction, during or after their formation, with polymerizable groups such as 3-aminophenyl acetylene or 3,6-endomethylene-1,2,3,6-tetrahydrophthalic anhydride. The diamines are novel classes of amines when Z is sulfur and X and/or Y are carbonyl or carbinol groups and when Z is oxygen and X, Y, or X and Y are carbinol groups.