Abstract: The present invention relates to a water curable resin formulation comprising: (a) an epoxy resin; (b) an aromatic amine curing agent, wherein the molar ratio of amine functional groups in said curing agent relative to the epoxy functional groups of said epoxy resin is 2:1 or less; and (c) a coupling agent comprising a siloxane group coupled to an epoxy reactive group.

Abstract: The present invention relates to a water curable resin formulation comprising: (a) an epoxy resin; (b) an aromatic amine curing agent, wherein the molar ratio of amine functional groups in said curing agent relative to the epoxy functional groups of said epoxy resin is 2:1 or less; and (c) a coupling agent comprising a siloxane group coupled to an epoxy reactive group.

Abstract: A method for reducing crazing in a plastics material characterised in that it comprises the steps of: (1) cleaning the surface of the material; and (2) exposing the cleaned surface to plasma of a monomer vapour so as to produce a substantially non-oxidising plasma polymer coating on the surface.

Abstract: The invention provides a method for promoting the curing reactions of an acetylenic oligomer or polymer, characterized in that the oligomer or polymer is cured in the presence of sulfur or an organic sulfur derivative which is capable of lowering the temperature of cure of the oligomer or polymer. The invention also provides a process for producing a polyimide oligomer or polymer containing an aliphatic or aromatic disulfide moiety which is covalently bound to, and forms an integral part of the oligomer or polymer and which is capable of lowering the temperature of cure of the oligomer or polymer, characterised in that a suitable amount of a diamino-disulfide or dianhydride-disulfide, or any suitable derivative or precursor thereof, is introduced into the mixture of aromatic diamines, tetracarboxylic dianhydrides, and the phenylethynyl-substituted amine or anhydride normally used for the reparation of the oligo-imide.

Abstract: A method for reducing crazing in a plastics material characterized in that it comprises the steps of:

Abstract: A process for the preparation of an oligomeric polyimide comprises: mixing a tetracarboxylic acid, a dianhydride, a partially hydrolysed dianhydride or a mixture thereof with a diamine in a reaction medium comprising greater than 80% by weight water, and heating mixture in said reaction medium at a temperature above 100° C. for a time sufficient to form said oligomeric polyimide.

Abstract: A method for the preparation of a diaminobisimide compound of the formula (I) substantially free of oligomers: ##STR1## wherein Ar.sup.1 is an optionally substituted aromatic residue which provides for good conjugation between the nitrogen containing groups; andAr is an optionally substituted aromatic residue characterized in that at least two molar proportions of an aromatic diamine of the formula (II)H.sub.2 N--Ar.sup.1 --NH.sub.2 (II)wherein Ar.sup.1 is as defined above,are heated with one molar proportion of an aromatic tetracarboxylic acid of the formula (III) or the corresponding dianhydride,(HOOC).sub.2 Ar(COOH).sub.2 (III)wherein Ar is as defined above,optionally in the presence of a polar solvent and optionally including 0.1 to 2 molar proportions of a tertiary amine.The compounds of formula (I) are useful curing agents in epoxy resin formulations.

Abstract: The invention relates to a PMR type resin which comprises a mixture of:(a) nadic acid of Formula (Ia) or a derivative thereof ##STR1## (b) a diaminobisimide of Formula (Ib) ##STR2## (c) an aromatic tetracarboxylic acid of Formula (Ic) or a derivative thereof ##STR3## the components (a), (b) and (c) being present in the approximate molar proportions of 2:n:n-1 respectively.

Abstract: A method for the preparation of diaminobisimide compounds of the formula (I) which are substantially free of oligomers and are useful as curing agents in epoxy resin formulations: ##STR1## wherein Ar.sup.1 is an optionally substituted aromatic residue which provides for good conjugation between the nitrogen containing groups; and Ar is an optionally substituted aromatic residue, comprising heating an aromatic diamine of the formula H.sub.2 N--Ar.sup.1 --NH.sub.2, with an aromatic tetracarboxylic acid of the formula (HOOC).sub.2 (COOH).sub.2 or the corresponding dianhydride.

Abstract: A method of modifying the surface properties of titanium dioxide pigments and fillers by forming on the particles a surface coating of an aluminium compound, the coating having a significant number of acidic sites with pKa values of less than 2.8.