Method for making pyrimidin-2-one and imidazol-2-one copolymerizable monomer derivatives

The method of producing a monoethylenically unsaturated copolymerizable monomer having the formula ##STR3## in which R.sub.1 is alkylene having 2 or 3 carbon atoms;

• R.sub.2 is alkylene having 2 to 10 carbon atoms;
• X is a radical selected from NH-, S-, and O- which initially carried Z;
• Z is an isocyanate-reactive hydrogen atom initially carried by R.sub.2 X;
• a is an integer from 1 to 5 to consume all the isocyanate groups on the polyisocyanate noted hereinafter other than the one consumed by R.sub.3 ;
• Q is an organic aliphatic or aromatic polyisocyanate carrying a+1 isocyanate groups;
• V is an isocyanate-reactive hydrogen atom initially carried by R.sub.3 ;
• R.sub.3 is the residue of a monohydroxy C.sub.1 -C.sub.12 alkyl maleate or fumarate which is connected to Q via its hydroxy group;
• and
• X and R.sub.3 are connected to Q via the isocyanate groups therein and Z and V are carried by the nitrogen atoms in said isocyanate groups which comprises,
• adding one mole of said polyisocyanate slowly to a mixture of one equivalent of said maleate or fumarate and enough of an alkyl alkylene urea supplying said X radical to consume the isocyanate functionality in excess of one equivalent, said polyisocyanate including one isocyanate group which is less reactive than the others and said hydroxy group carried by said maleate or fumarate being less reactive with the isocyanate group than said X radical carried by said alkyl alkylene urea, first reacting the more reactive isocyanate group of said polyisocyanate with the X radical of said alkyl alkylene urea by maintaining conditions adequate for that reaction, but inadequate for reaction with the hydroxy group carried by said maleate or fumarate, and then raising the temperature to cause the less reactive isocyanate group of said polyisocyanate to react with the hydroxy group carried by said maleate or fumarate.