Phosphorus containing compounds and epoxy resins thereof

A laminate composite structure comprising:

• (a) a glass fiber fabric,
• (b) an epoxy,
• (c) a copper foil, and
• (d) a phosphorus containing compound according to formula (I):
• wherein,
• X is an aromatic hydrocarbon group having 6 to 30 carbon atoms or a bivalent linear or branched alkylene group of 1 to 8 carbon atoms,
• RA is selected from an alkyl group having 1 to 6 carbon atoms, a phenyl group, a napthyl group, and an aromatic phenol group,
• w is an integer of 1 to 9,
• R1, R2, R3, and R4 are independently selected from H, C1-C10 alkyl, C1-C10 alkoxy, and C3-C10 cycloalkyl,
• R5 is selected from the group consisting of C1-C10 alkyl, C1-C10 alkoxy, C3-C10 cycloalkyl, and Ar3, and
• Ar1 and Ar2 are independently selected from the following structure:
• wherein Ar3 is selected from the following structures:
• wherein:
• R6 and R7 are independently selected from the group consisting of H, C1-C10 alkyl group, C1-C10 alkoxy, and a cyclic alkyl group having 3-10 carbon atoms,
• m and n are independently an integer from 0 to 3, and m plus n is less than 5,
• R8 is absent or is selected from the group consisting of —CH2—, —(CH3)2C—, —CO—, —SO2—, and —O—, and
• R9 is absent or is —(CH2)p, wherein p is an integer from 1 to 20, and z is 1.