摘要:
The invention is an encapsulated active agent comprising an active agent encapsulated in a crystallizable or thermoplastic polymer wherein the particle size of the encapsulated active agent is 3,000 microns or less wherein the active agent is not significantly extractable from the particles under ambient conditions. In another embodiment the invention is a process for preparing an encapsulated agent which comprises a) contacting an active agent with a crystallizable or thermoplastic polymer wherein the polymer is molten and the active agent in not volatile under the contacting conditions; b) forming particles of about 3000 microns or less; and c) exposing the particles to conditions such that the portion of the particle at and near the surface undergoes rapid solidification. The encapsulated active agents of the invention do not require washing in order for them to be stable in curable compositions. These encapsulated active agents can be designed to release the active agent at a desired temperature. The encapsulated agents of the invention demonstrate excellent stability at ambient temperatures and exhibit relatively rapid reactivity upon release of the active agent. Furthermore, the presence of the encapsulating agent does not result in deterioration of adhesive or elastomer properties of a cured composition after preparation.
摘要:
An active material encapsulated in a coating material immiscible therewith is contacted with a solvent that dissolves residual active material on the surface of the coating material without dissolving the coating material. The resultant encapsulated material has improved stability as compared to the material not contacted with solvent.
摘要:
A thixoropic adhesive composition exhibiing good sag resistance is prepared comprising a mixture of a polymer-modified epoxy resin and a rheological control agent. The polymer-modified epoxy resin is preferably a dispersion of acrylic elastomer in an epoxy resin in which the acrylic elastomer particles have added hydroxyl functionality which interacts favorably with rheological control agents, such as fumed silica. Acrylic epoxy resin dispersions containing added hydroxyl functionality give improved rheological control.
摘要:
Novel radiation-curable, water-compatible, resinous compositions result from (1) terminally unsaturated molecules which are the esters of an epoxy compound and (2) the reaction product of a glycidyl ether and an unsaturated acid having at least one glycidyl group per molecule converted to an onium salt of a quaternary ammonium or amine salt, with the anion of an inorganic or organic acid.
摘要:
An adduct of a heteroatomic monomer, e.g., gamma-methacryloxypropyl trimethoxysilane and a monoahl, e.g., a monohydroxyl polyalkylene oxide or a polyahl, e.g., a polypropylene glycol, is usefully employed in the preparation of stable copolymer dispersions of the type used in the production of polyurethane foams and polyurethane elastomers.The copolymer dispersion is prepared by addition copolymerization of (1) the adduct with (2) ethylenically unsaturated monomer(s), e.g., styrene or mixture thereof with acrylonitrile, while (1) and (2) are dispersed or dissolved in an excess of a polyahl, i.e., an active hydrogen polyfunctional compound.
摘要:
A stable copolymer dispersion is prepared by addition copolymerization of (1) a monomeric adduct of an active hydrogen compound, e.g., a polyether polyol, and an acrylyl compound such as methacryloyl chloride with (2) ethylenically unsaturated monomer(s), e.g., styrene or a mixture thereof with acrylonitrile, while (1) and (2) are dispersed or dissolved in an excess of an active hydrogen polyfunctional compound such as a polyether polyol. The molar ratio of acrylyl moiety to active hydrogen compound is less than 0.1:1. The resulting dispersion has a controlled particle size and a viscosity such that it is suitably employed in the production of polyurethane foams.
摘要:
Sulfonium-stabilized, water-compatible, radiation-curable vinyl ester resins are prepared by the process of reacting an epoxy resin having on the average at least one vicinal epoxy group with a mercaptan and with an unsaturated monocarboxylic acid to form vinyl ester resins containing sulfide moieties which are then reacted with a protonic acid and an alkylene oxide.Compounds so prepared can be diluted with water and used as coatings.
摘要:
Novel sulfonium-stabilized, radiation-curable, water-compatible, water-in-oil emulsions and a method of preparation are described. As an example, one such emulsion was prepared by reacting the diglycidyl ether of a polypropylene glycol with essentially a stoichiometric equivalent of acrylic acid, about 0.3 equivalent of bis(2-hydroxyethyl)-sulfide and 1.5 equivalents of H.sub.2 O.
摘要:
In one embodiment the invention is An adhesive composition comprising a) a polymer having a flexible backbone and a reactive moiety capable of cross-linking, b) a particle comprising an active agent encapsulated in an encapsulating agent wherein the active agent comprises a catalyst for cross-linking of the reactive moiety, a curing agent for the reactive moiety, an accelerator for the curing reaction or a mixture thereof; and the encapsulating agent comprises a side chain crystallizable polymer wherein the active agent is not substantially extractable from the particle at ambient conditions in a first extraction after particle formation.
摘要:
The present invention is a one-part adhesive composition comprising:A) an isocyanate functional polyurethane prepolymer;B) a catalyst capable of catalyzing the reaction of isocyanate moieties with an isocyanate reactive compound;C) particles comprising a curing agent for an isocyanate functional. polyurethane prepolymer encapsulated within a coating material;wherein the prepolymer has a free isocyanate content of from about 0.8 to about 2.2 percent. In another embodiment the invention is a process for bonding two substrates together which comprises rupturing the encapsulated curing agent particles so as to contact the curing agent with the prepolymer in the adhesive composition, contacting the adhesive composition of the invention with at least one of the substrates and contacting the substrates together along the portion of the substrate(s) to which the adhesive has been applied before the adhesive applied cures and allowing the adhesive to cure and bond the substrates together.