摘要:
The epihalohydrin yield in a process for preparing low molecular weight epoxy resins by coupling a polyhydric phenol and an epihalohydrin in the presence of an alkali metal hydroxide and subsequent dehydrohalogenation is improved by employing stoichiometric quantities of the alkali metal hydroxide with respect to the polyhydric phenol in the coupling reaction and also conducting the coupling reaction in the presence of a halohydrin that is at least as reactive as the halohydrin being formed.
摘要:
A class of compounds which inhibits the reaction of a polyepoxide with a curing agent at low temperatures including an epoxy resin composition containing a) a polyepoxide; b) an amine or amide curing agent for the polyepoxide; c) at least about 15 meq (per equivalent of polyepoxide) of a catalyst for the reaction of the polyepoxide with the curing agent; and d) a cure inhibitor selected such that: (1) at about 171.degree. C. the composition has a gel time that is at least about 50 percent longer than a similar composition without the inhibitor, and (2) at about 175.degree. C. and higher the composition cures in no more than about 50 minutes such that the composition cures rapidly with high cross-link density because it has a high catalyst loading, while the inhibitor lengthens the gel time to permit laminating and other processing.
摘要:
Graft copolymers containing:(1) a phenolic resin; and (2) a poly(alkylene oxide) chain pendant to the phenolic resin,selected such that the graft copolymer has a solubility of no more than about 10 g/L in water, are taught. The graft copolymers are useful in coatings compositions with a curing agent, a solvent, and optionally an epoxy resin. The curable compositions have improved flexibility and/or solvent resistance. They are particularly useful in can coatings.
摘要:
The products resulting from contacting an organic phosphine or arsine with an inorganic acid having a weak nucleophilic anion provide for relatively stable compositions when admixed with a compound containing an average of more than one vicinal epoxide group per molecule and which optionally contains a compound containing an average of more than one phenolic hydroxyl group per molecule.
摘要:
The 2-functional component of substituted phenol-aldehyde novolac resins is reduced. Epoxy novolac resins prepared from the novolac resin containing reduced quantities of 2-functional product exhibit increased Tg values when cured.
摘要:
Curable amide modified epoxy resins are prepared by polymerizing (I) the reaction product of (A) the reaction product of (1) an epoxy resin having an average of more than one 1,2-epoxy group per molecule and an average of from about 0 to about 30 aliphatic hydroxyl groups per molecule such as a diglycidyl ether of bisphenol A and (2) (a) a material having only one primary amine group per molecule such as monoethanolamine and (b) a material having only one secondary amine group per molecule such as diethanolamine wherein (a) and (b) are added sequentially with (a) being added first, or as a mixture with (B) an anhydride of an unsaturated dicarboxylic acid such as maleic anhydride with (II) a polymerizable ethylenically unsaturated monomer or mixture of monomers such as styrene and methacrylic acid. The resultant resin can be employed as is in the preparation of organic solvent borne coatings or it can be neutralized with a base so as to improve its stability in the preparation of aqueous coatings.
摘要:
New epoxy resins are prepared by reacting a hydroxybenzamide or derivative thereof with an epihalohydrin followed by dehydrohalogenation. These epoxy resins have crystalline melting points, self-cure at elevated temperatures and cure rapidly in the presence of the usual epoxy resin curing agents. Also disclosed are hydrolyzed products of these epoxy resins and subsequent reactions with polyisocyanates.
摘要:
The 2-functional content of phenol-aldehyde novolac resins is reduced by water extraction. Epoxy novolac resins prepared from the novolac resin containing less 2-functional product exhibit increased Tg values when cured.
摘要:
Tetrahydrocarbyl phosphonium bicarbonate salts are described which are unexpectedly effective as catalysts for promoting the reaction between (a) vicinal epoxides and (b) phenols. These catalysts are particularly useful in preparing high molecular weight epoxy resins by the advancement reaction of an epoxy resin with a polyhydric phenol.
摘要:
A process reaction between: (1) a compound that contains one or more epoxide moieties per molecule, and (2) a compound that contains one or more primary aliphatic hydroxyl groups per molecule; is catalyzed by: (3) a catalyst compound containing one or more trifluoromethanesulfonate moieties and one or more silyl moieties and run at a temperature of no more than 130.degree. C., such that the catalyst preferably catalyzes reaction at the primary aliphatic hydroxyl group, so that the resulting resin does not gel.