摘要:
Curable suspensions of an epoxy resin formulation comprisinga) a storage-stable suspension of an epoxy resin and a toughener suspended therein which contains no groups that react with a curable epoxy resin system,b) dicyandiamide, a polycarboxylic acid, a polycarboxylic anhydride, a polyamine, a polyaminoamide, an amino group-containing adduct of an amine and a polyepoxide, a polyol or a catalytically curing hardener, and, as optional components,c) a curing catalyst, conventional fillers or reinforcing materials,are particularly suitable for use as casting resins, laminating resins or adhesives.
摘要:
A storage-stable suspension of an epoxy resin hardener and a toughener useful as a molding composition is prepared via a) the addition of an organic solvent to an aqueous emulsion of the toughener when using a water-sensitive hardener, such as a polycarboxylic anhydride, removing the water as an azeotrope by vacuum distillation, then adding the epoxy resin hardener and removing the residual solvent by vacuum distillation, or b) the addition of an aqueous emulsion of the toughener with or without an organic solvent to the epoxy resin hardener when using a water-insensitive hardener such as a polyamine, and removing the water and any organic solvent by vacuum distillation.
摘要:
Storage-stable suspension comprised of a solid or liquid epoxy resin hardener and a solid or liquid toughener suspended therein is distinguished by excellent homogeneous dispersion of the toughener in the epoxy resin hardener and are suitable for preparing suspensions of curable epoxy resin compositions.
摘要:
Hardenable mixtures comprising(a) an epoxide resin,(b) a latent epoxide resin hardener which starts to react only at a temperature of at least 80.degree. C. (measured by DSC at a heating rate of 10.degree. C./minute),(c) an amine having at least one amine hydrogen and(d) a thiol having at least one SH group, either the amine (c) having at least two hydrogen atoms bound to one or more nitrogen atoms or the thiol (d) having at least two SH groups, and the difference between the reaction maxima in the DSC diagram at a heating rate of 10.degree. C./minutes being at least 30.degree. C., are suitable for the production of crosslinked products, especially for the production of flexible prepregs having a non-critical B stage and a very good storability.
摘要:
A thermosetting composition comprising (a) at least one phosphorous-free dihydrobenzoxazine component; (b) at least a quaternary ammonium salt and (c) optionally a compound comprising at least an epoxy group is disclosed. Cured products made from these compositions have valuable chemical, physical and mechanical properties.
摘要:
A thermosetting composition comprising (a) 97.9 to 40 percent by weight of at least one bis(dihydrobenzoxazine) prepared by the reaction of an unsubstituted or substituted bisphenol with at least one unsubstituted position ortho to each hydroxyl group, formaldehyde and a primary amine; (b) 2 to 50 percent by weight of at least one organic polyamine; and (c) 0.1 to 10 percent by weight of at least one curing catalyst, selected from the group of carboxylic acids, sulfonic acids and phosphonic acids having at least two acid groups and no other reactive groups; wherein the percent by weight refer to the total amount of components (a), (b) and (c) in the composition, with the proviso that (a), (b) and (c) add up to 100 percent by weight; and (d) and optionally other components. Cured products of these compositions show valuable chemical, physical and mechanical properties.
摘要:
Compositions containing (a) a liquid epoxy resin, (b) an aliphatic or cycloaliphatic primary monoamine and/or an aliphatic or cycloaliphatic disecondary diamine, (c) a latent curing agent for the epoxy resin (a) which does not react until temperatures above 70° C. (measured by means of DSC at a heating rate of 1O° C./min), (d) a photopolymerizable compound and (e) a photoinitiator, the ratio of the number of equivalents of epoxy groups to that of polymerizable groups being 1:0.01 to 1:0.7, are suitable as impregnating resins.
摘要:
A thermosetting composition comprising (a) (a) at least one phosphorous-free dihydrobenzoxazine component; (b) at least a sulfonium salt and (c) optionally a compound comprising at least an epoxy group is disclosed. Cured products made from these compositions have valuable chemical, physical and mechanical properties.
摘要:
A composition, comprising(a) at least one tight cycloolefin,(b) a catalyst for the ring-opening metathesis polymerisation,(c) a filler, and(d) a silane of formula I ##STR1## wherein R is a polyvalent organic group having 2 to 100 carbon atoms, where one or more than one carbon atom can be replaced by O, S, N or Si atoms and Y.sub.1, Y.sub.2 and Y.sub.3 are each independently of one another C.sub.1 -C.sub.20 alkyl, C.sub.5 -C.sub.20 aryl, C.sub.6 -C.sub.20 aralkyl, C.sub.5 -C.sub.12 cycloalkyl, C.sub.2 -C.sub.20 -alkoxyalkyl or C.sub.1 -C.sub.20 acyl, gives cured products having excellent mechanical and electrical properties and which is particularly suitable as encapsulating material for electrical and electronic components.