Copolymer of a bisphenol diglycidyl ether and a phenolphthalene and/or a phenolphthalimidine, method for the preparation thereof, article comprising the copolymer, and compositions comprising the copolymer

1. A method of forming a copolymer, the method comprising:

adding

an oligomeric bisphenol diglycidyl ether to

an N-phenylphenolphthalimidine wherein the phenyl group bound to nitrogen is unsubstituted or substituted

in a molar ratio of 0.98:1 to 1.02:1 in the presence of a tertiary amine catalyst to form a reaction mixture; and

reacting

the oligomeric bisphenol diglycidyl ether and

the N-phenylphenolphthalimidine

to form a copolymer;

wherein the oligomeric bisphenol diglycidyl ether is added to the N-phenylphenolphthalimidine such that an excess of phenolic groups relative to epoxy groups is maintained in the reaction mixture.

2. The method of claim 1 , wherein the oligomeric bisphenol diglycidyl ether has the structure

wherein m is, on average, 1.2 to 10; each occurrence of w is independently 0 or 1; each occurrence of x is independently 0, 1, 2, 3, or 4; each occurrence of R 1 is independently halogen, C 1 -C 12 hydrocarbylthio, C 1 -C 12 hydrocarbyloxy, C 2 -C 12 halohydrocarbyloxy wherein at least two carbon atoms separate the halogen and oxygen atoms, or unsubstituted or substituted C 1 -C 12 hydrocarbyl; and each occurrence of Y is independently

wherein each occurrence of R 4 , R 5 , R 6 , and IC is independently hydrogen or an unsubstituted or substituted C 1 -C 12 hydrocarbyl; and

the N-phenylphenolphthalimidine has the structure

wherein each occurrence of y is independently 0, 1, 2, 3, or 4; and each occurrence of R 2 is independently halogen, C 1 -C 12 hydrocarbylthio, C 1 -C 12 hydrocarbyloxy, C 2 -C 12 halohydrocarbolyoxy wherein at least two carbon atoms separate the halogen and oxygen atoms, or unsubstituted or substituted C 1 -C 12 hydrocarbyl; and R 3 is independently unsubstituted or substituted phenyl.

3. The method of claim 1 , wherein the tertiary amine catalyst comprises triethylamine, tri-n-propylamine, tri-n-butylamine, dimethylaniline, diethylaniline, alpha-methylbenzyldimethylamine, N,N-dimethylaminoethanol, N,N-dimethylaminopyridine, alkylimidazoles, or a combination thereof.

4. The method of claim 1 , wherein the copolymer has a weight average molecular weight of 10,000 to 100,000 atomic mass units.

5. The method of claim 1 ,

wherein said reacting comprises reacting the oligomeric bisphenol diglycidyl ether and the N-phenylphenolphthalimidine in a molar ratio of 0.99:1 to 1.01:1;

wherein the oligomeric bisphenol diglycidyl ether has the structure

wherein m is, on average, 1.5 to 7;

wherein the N-phenylphenolphthalimidine has the structure

and

wherein the copolymer has a weight average molecular weight of 20,000-40,000 atomic mass units.