摘要:
The invention relates to a process for the preparation of polyurethane or polyurethane-polyurea molded parts by reacting organic polyisocyanates, polyols and chain extenders in the presence of monocyclic amidines having the formula ##STR1## as catalyst or catalyst mixtures of monocyclic amidines having the formula (I) and (a) tertiary amines, (b) metal salts having the formula Me X.sub.n Y.sub.m (II), and/or (c) optionally-substituted aliphatic carboxylic acids. R.sup.1 and R.sup.2, Me, X, Y, n, and m are defined herein.
摘要:
A process for the manufacture of partially dehydrated organic polymer polyol dispersions from the reaction of polyhydroxyl compounds and aqueous polymer dispersions wherein the problem of excessive viscosity is overcome by mixing the reactants with a recycled partially dehydrated polyol polymer dispersion, removing water from the reaction mixture, removing a portion of the partially dehydrated polyol polymer dispersion, and recycling the remainder.
摘要:
Vinyl ester resins possess unsaturated terminal groups and are based on polyphenols of the formulaC(ArOH).sub.m (R').sub.p --(CR.sub.2).sub.n --C(ArOH).sub.m (R").sub.p (I)or(ArOH)--CH.sub.2 --Ar--CH.sub.2 --[(ArOH)--CH.sub.2 --Ar--CH.sub.2 ].sub.n --(ArOH) (II)wherein R, R' and R" may be identical or different and are each H or CH.sub.3, Ar is phenylene which is unsubstituted or substituted by methyl or methoxy, n is 0, 1 or 2, m is 1 or 2 and p is 3-m.
摘要:
A solvent-free curable composition has a long shelf life and consists ofA 100 parts by weight of an epoxy resin andB from 10 to 100 parts by weight of .[.,.]. .Iadd.4,4-bis-(para-aminobenzoyl)-piperazine .Iaddend.as a curing agent for the epoxy resin, .[.an aromatic diamine containing ##STR1## groups,.]. with or without C from 0.01 to 5 parts by weight of an accelerator, the curing agent for the epoxy resin being finely dispersed in the latter and preferably having a particle size of less than 10 .mu.m. .[.The preferred epoxy resin curing agent is 4,4'-diaminodiphenyl ketone..]. The curable composition is used in particular for the preparation of fiber-reinforced materials.
摘要:
Fiber-reinforced materials are produced by a process in which a heat-stable thermoplastic aromatic polyether A which contains reactive groups, preferably nitrile groups and/or sulfur bridges and/or arylthio or alkylthio groups, if necessary together with a heat-stable thermoplastic polymer B which does not contain any reactive groups, is applied onto reinforcing fibers, the resulting semi-finished product is molded and, in the molding obtained, the plastic matrix is crosslinked so that the glass transition temperature increases and it becomes virtually insoluble.
摘要:
A solvent-free curable composition has a long shelf life and consists ofA 100 parts by weight of an epoxy resin andB from 10 to 100 parts by weight of, as a curing agent for the epoxy resin, an aromatic diamine containing ##STR1## groups, with or without C from 0.01 to 5 parts by weight of an accelerator, the curing agent for the epoxy resin being finely dispersed in the latter and preferably having a particle size of less than 10 .mu.m. The preferred epoxy resin curing agent is 4,4'-diaminodiphenyl ketone. The curable composition is used in particular for the preparation of fiber-reinforced materials.
摘要:
Fiber-reinforced materials are produced by impregnating continuous filaments with a melt of a polyarylene sulfide ketone, preferably one having a reduced viscosity .eta..sub.red of from 0.1 to 0.5 [dl.g.sup.-1 ], shaping the resulting semi-finished product to give a finished article and heating the latter for not less than 15 minutes at above the crystallite melting point of the polyarylene sulfide ketone, the latter undergoing crosslinking and its glass transition temperature Tg increasing by not less than 5.degree. C.