Phosphine oxide hydroxyaryl mixtures with novolac resins for co-curing epoxy resins
AssigneePABU Services, Inc.
InventorsLarry D. Timberlake, Mark V. Hanson, E. Bradley Edwards
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Abstract
There is disclosed a novel mixture of polyhydroxy phenolic curing agents, such as novolac resins blended with a mixture of mono, bis and tris hydroxyaryl phosphine oxides for co-curing epoxy resins and imparting flame resistance thereto. A preferred composition includes a mixture of monohydroxyaryl, bishydroxyaryl and trishydroxyaryl phosphine oxide and a benzoguanamine/phenol/formaldehyde terpolymer which is used along with an epoxy resin to produce flame-resistant printed wiring boards without the use of halogens.
Claims40
A polyhydroxy mixture for co-crosslinking an epoxy resin and imparting flame resistance comprising.
- (a) a mixture of phosphine oxides including hydroxyaryl phosphine oxides of the formulae:
- (i) a mono(hydroxyaryl)phosphine oxide of the formula:
- 10
- wherein R1 is a divalent, substituted or unsubstituted arylene moiety and R2 is a monovalent, substituted or unsubstituted aryl moiety or is an alkyl moiety or is an aralkyl moiety;
- and
- (ii) a bis(hydroxyaryl)phosphine oxide of the formula:
- 11
- wherein R1 and R2 are defined as above;
- and
- (iii) a tris(hydroxyaryl)phosphine oxide of the formula:
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- wherein R1 is defined as above;
- and
- (iv) optionally containing minor amounts of a pentavalent phosphine oxide of the formula:
- 13
- wherein R2 is defined as above;
- and
- (b) a phenolic co-crosslinking composition comprising a phenolic component having a hydroxy functionality of two or more.
A flame-retardant curable epoxy composition comprising:
- (a) an epoxy resin;
- (b) a co-crosslinking polyhydroxy mixture including:
- (i) a mixture of phosphine oxides including hydroxyaryl phosphine oxides of the formulae:
- (A) a mono(hydroxyaryl)phosphine oxide of the formula:
- 14
- wherein R1 is a divalent, substituted or unsubstituted arylene moiety and R2 is a monovalent, substituted or unsubstituted aryl moiety or is an alkyl moiety or is an aralkyl moiety;
- and
- (B) a bis(hydroxyaryl)phosphine oxide of the formula:
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- wherein R1 and R2 are defined as above;
- and
- (C) a tris(hydroxyaryl)phosphine oxide of the formula:
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- wherein R1 is defined as above;
- and
- (D) optionally containing minor amounts of a pentavalent phosphine oxide of the formula:
- 17
- wherein R2 is defined as above;
- and
- (ii) a phenolic co-crosslinking composition comprising a phenolic component having a hydroxyfunctionality of two or more.
Dependencies are inferred from the claim text.