Acid-modified copolymers of drying oil acids, maleic-polyhydric alcohol esters, and process of making same

Claim 1

THE PROCESS OF MAKING COATING MATERIAL, WHICH COMPRISES THE STEPS OF: (1) HEATING 2 MOLES OF A MONOHYDROXYL-CONTAINING ESTER OF FORMULA DN-1POH, WHEREIN D IS THE ACID FREE FROM CONUNPOLYMERIZED DRYING OIL ACID FREE FROM CONJUGATED UNSATURATION, P IS THE HYDROXYL-FREE RADICAL OF AN ESTERIFIABLE POLYHYDRIC ALCOHOL P(OH)N, AND N IS THE NUMBER OF HYDROXYL GROUPS IN SAID POLYHYDRIC ALCOHOL, WITH FROM 0.3 TO 0.9 MOLE OF MALEIC ANHYDRIDE AT FROM 140* C. TO 200* C. TO FORM A MALEIC ACID HALF-ESTER IN THE PRESENCE OF AN EXCESS OF SAID HYDROXY-ESTER, (2) ADDING A LIQUID MONOMERIC UNSATURATED POLYMERIZABLE COMPOUND IN WHICH THE UNSATURATION IS DUE TO A SINGLE TERMINAL ETHYLENIC GROUP >C=CH2 AND WHICH IS COPOLYMERIZABLE WITH SAID MALEIC HALF-ESTER AND HEATING THE MIXTURE AT BETWEEN 120* C. AND BELOW 200* C. TO COPOLYMERIZE SAME, THE PROPORTION OF LIQUID MONOMERIC COMPOUND IN THE MIXTURE BEING FROM 5% TO 90%, AND (3) ADDING A CARBOXYLIC ACID REACTABLE ONLY BY ESTERIFICATION IN AMOUNT EQUIVALENT TO THE DIFFERENCE BETWEEN 1 MOLE OF MALEIC ANHYDRIDE AND THE AMOUNT THEREOF USED IN STEP 1, AND HEATING THE COMPOSITION AT FROM 200* TO 300* C. TO ESTERIFY SAME.