Metharcylate prepolymer containing triazine ring structure, its preparation, and setting composition and resin

A method for preparing a methacrylate prepolymer containing triazine ring structure expressed as the formula:

• ##STR8## where, the value of n is one the average from 1 to 10;
• R1 is ##STR9## R2, R3, R4, R5, R8, and R9 are radicals selected from hydrogen radicals and divalent functional radicals such as --CH.sub.2 -- and --CH.sub.2 OCH.sub.2 --;
• where the radical --CH.sub.2 OCH.sub.2 -- links triazine rings;
• R6 and R7 are monovalent functional radicals selected from hydroxyl radicals and functional radicals with ethylene unsaturation as denoted by the formula:
• ##STR10## and where R6 and R7 are bonded as terminal groups to the --CH.sub.2 -- radical of R2 through R5, R8 and R9 which are unbound to a triaxine ring;
• at least one functional group expressed as formula (III) exists in the prepolymer;
• and R10 is either a hydrogen radical or CH.sub.3 ;
• synthesized in a single step reaction, without use of a solvent, from an aminotriazine compound, having an average molecular weight to 200 to 8,000, a p-formaldehyde, and a 2-hydroxyethyl methacrylate;
• said method comprising the single step of:
• forming a three constituent mixture by dissolving the aminotriazine compound and the p-formaldehyde in the 2-hydroxyethyl methacrylate;
• and heating said mixture, to react the three constituents, at a temperature in the range of about 70.degree. C. to 150.degree. C. while blowing one of oxygen and air into the mixture for dissolution.