A curing agent composition comprising anhydride and approximately equimolar amount of tertiary amine or imidazole and carboxylic acid, the amine being 1-piperidinylethanol (N-hydroxyethyl-piperidine, NHEP) represented by the structure below or an imidazole represented by the structure below:

##STR00001##

where R.sub.1=H, a C1-C20 straight chain or branched alkyl, or a monocyclic aryl; R.sub.2=a C1-C20 straight chain or branched alkyl, or a monocyclic aryl. The carboxylic acid is represented by RCOOH; R=a C1-C20 straight chain or branched alkyl, or a monocyclic aryl. The composition comprises a lower ratio of epoxy resin to anhydride (1:0.4-0.6) than typically used (1:0.8-1.1). In addition, it uses a higher loading of the hindered latent tertiary amine or the imidazole in combination with the carboxylic acid (wt % ratio of combined amine and carboxylic acid to anhydride 10%). With this composition a full cure can be achieved in less than 2 hr at a significantly lower temperature (100 C.).

A curable epoxy composition includes an epoxy resin composition; a hardener composition comprising an aromatic dianhydride curing agent of the formula

##STR00001##

wherein T is O, S, SO.sub.2, SO, C.sub.yH.sub.2y wherein y is an integer from 1 to 5 or a halogenated derivative thereof, or OZO wherein Z is an aromatic C.sub.6-24 monocyclic or polycyclic moiety optionally substituted with 1 to 6 C.sub.1-8 alkyl groups, 1 to 8 halogen atoms, or a combination thereof, and the aromatic dianhydride has a melting point of 220 C. or less; and at least one additional anhydride curing agent different from the aromatic dianhydride curing agent; and 0.1 to 5 wt % of a heterocyclic accelerator, wherein the heterocyclic accelerator comprises a substituted or unsubstituted C.sub.3-6 heterocycle comprising 1 to 4 ring heteroatoms, wherein each heteroatom is nitrogen, oxygen, phosphorus, silicon, or sulfur.

A curable epoxy composition includes an epoxy resin composition; a hardener composition comprising an aromatic dianhydride curing agent of the formula

##STR00001##

wherein T is O, S, SO.sub.2, SO, C.sub.yH.sub.2y wherein y is an integer from 1 to 5 or a halogenated derivative thereof, or OZO wherein Z is an aromatic C.sub.6-24 monocyclic or polycyclic moiety optionally substituted with 1 to 6 C.sub.1-8 alkyl groups, 1 to 8 halogen atoms, or a combination thereof, and the aromatic dianhydride has a melting point of 220 C. or less; and at least one additional anhydride curing agent different from the aromatic dianhydride curing agent; and 0.1 to 5 wt % of a heterocyclic accelerator, wherein the heterocyclic accelerator comprises a substituted or unsubstituted C.sub.3-6 heterocycle comprising 1 to 4 ring heteroatoms, wherein each heteroatom is nitrogen, oxygen, phosphorus, silicon, or sulfur.

Epoxy curing agents are disclosed having an epoxy curing agent comprising at least one room temperature ionic liquid salt, the room temperature ionic liquid salt being a reaction product of (a) at least one polyalkylene polyamine compound represented by formula (I):

##STR00001##

wherein x, y, and z are integers of 2 and 3, m and n and integers of 1-3; and (b) an organic acid having pKa (the negative of the logarithm of the acid dissociation constant) less than 6. The liquid salt is a stable liquid at a temperature greater than 15 C. Curable epoxy-based compositions including the curing agent and articles formed by the curable epoxy-based compositions are also disclosed.

Epoxy curing agents are disclosed having an epoxy curing agent comprising at least one room temperature ionic liquid salt, the room temperature ionic liquid salt being a reaction product of (a) at least one polyalkylene polyamine compound represented by formula (I):

##STR00001##

wherein x, y, and z are integers of 2 and 3, m and n and integers of 1-3; and (b) an organic acid having pKa (the negative of the logarithm of the acid dissociation constant) less than 6. The liquid salt is a stable liquid at a temperature greater than 15 C. Curable epoxy-based compositions including the curing agent and articles formed by the curable epoxy-based compositions are also disclosed.

An electrical device includes at least one cross-linked layer obtained from a polymer composition that has: at least one polymer comprising one or more epoxy function(s), and at least one cross-linking agent. The cross-linking agent is selected from: a non-aromatic cyclic amine, an imidazole of formula (I) ##STR00001## where R.sub.1 and R.sub.2 independently represent a hydrogen atom or a hydrocarbon group, R.sub.3 and R.sub.4 independently represent a hydrogen atom or a hydrocarbon group, or R.sub.3 and R.sub.4 form, together with the carbon atoms of the imidazole ring to which they are attached, a ring, with the imidazole being associated with a cross-linking co-agent having at least one reactive function capable of reacting with the epoxy function of said polymer, and, a mixture thereof.

An electrical device includes at least one cross-linked layer obtained from a polymer composition that has: at least one polymer comprising one or more epoxy function(s), and at least one cross-linking agent. The cross-linking agent is selected from: a non-aromatic cyclic amine, an imidazole of formula (I) ##STR00001## where R.sub.1 and R.sub.2 independently represent a hydrogen atom or a hydrocarbon group, R.sub.3 and R.sub.4 independently represent a hydrogen atom or a hydrocarbon group, or R.sub.3 and R.sub.4 form, together with the carbon atoms of the imidazole ring to which they are attached, a ring, with the imidazole being associated with a cross-linking co-agent having at least one reactive function capable of reacting with the epoxy function of said polymer, and, a mixture thereof.

The present invention relates to a halogen-free resin composition and a prepreg and a laminated board prepared therefrom. The halogen-free resin composition contains the following components in parts by weight: 50-100 parts of an epoxy resin; 20-70 parts of benzoxazine; 5-40 parts of a polyphenyl ether; 5-40 parts of allyl benzene-maleic anhydride; 10-60 parts of a halogen-free flame retardant; 0.2-5 parts of a curing accelerator, and 20-100 parts of a filler. The prepreg and laminated board prepared from the halogen-free resin composition have comprehensive performances such as a low dielectric constant, a low dielectric loss, an excellent flame retardance, heat resistance, cohesiveness and moisture resistance, etc., and are suitable for use in a halogen-free high multilayer circuit board.

The present invention relates to a halogen-free resin composition and a prepreg and a laminated board prepared therefrom. The halogen-free resin composition contains the following components in parts by weight: 50-100 parts of an epoxy resin; 20-70 parts of benzoxazine; 5-40 parts of a polyphenyl ether; 5-40 parts of allyl benzene-maleic anhydride; 10-60 parts of a halogen-free flame retardant; 0.2-5 parts of a curing accelerator, and 20-100 parts of a filler. The prepreg and laminated board prepared from the halogen-free resin composition have comprehensive performances such as a low dielectric constant, a low dielectric loss, an excellent flame retardance, heat resistance, cohesiveness and moisture resistance, etc., and are suitable for use in a halogen-free high multilayer circuit board.

Provided are a curable resin composition capable of providing excellent heat resistance and toughness for a cured product, in which these physical properties are less deteriorated even in a case of being exposed to humidity and heat conditions, and a cured product, a fiber reinforced composite material, and a molded article thereof. The curable resin composition includes an epoxy resin and a curing agent, in which the epoxy resin is an epoxy resin obtained by the polyglycidyl-etherification of a phenol novolac resin. The phenol novolac resin contains bisphenol F having different binding sites, and in the bisphenol F components, the content of the [o, p] conjugate is in a range of 30% to 45% relative to the total of the [o, p] conjugate+the [o, o] conjugate+the [p, p] conjugate in terms of the area ratio according to a liquid chromatography measurement.