Compositions with ph responsive copolymer containing maep and/or mahp and methods for using same

An aqueous composition, comprising water and a pH responsive copolymer of unsaturated copolymerizable monomers, said unsaturated copolymerizable monomers comprising, based on total weight of monomers:

• A. about 0.1-70 weight percent first acidic monomer selected from at least one member of the group consisting of mono-[2-(methacryloyloxy)ethyl]phthalate and mono-[2-(Methacryloyloxy)ethyl hexahydro]phthalate,
• B. about 0-45 weight percent of at least one C3-C8 alpha beta-ethylenically unsaturated second acidic monomer, preferably a C3-C8 alpha beta-ethylenically unsaturated carboxylic acid monomer;
• C. about 15-70 weight percent of at least one nonionic, copolymerizable C2-C12 alpha, beta-ethylenically unsaturated monomer;
• and
• D. about 0 to 30 weight percent of at least one nonionic ethylenically unsaturated hydrophobic monomer.

A process comprising the steps of:

• mixing 100 parts by weight 2-hydroxyethy methacrylate (HEMA) and 0.1 to 0.5 parts by weight 4-methoxyphenol (MEHQ) to form a mixture;
• heating the mixture to a set point of 70-100° C. with NOx sparge and then adding 25-50 parts by weight phthalic anhydride as a first dose of phthalic anhydride to the heated mixture;
• after adding the first dose of phthalic anhydride then adding 1-3 parts by weight imidazole to the mixture;
• after adding the imidazole then adding 50 to 90 parts by weight phthalic anhydride as a second dose of phthalic anhydride;
• after adding the second dose of phthalic anhydride then heating the reaction mixture at 70-90° C. to form mono-[2-(methacryloyloxy)ethyl]phthalate;
• and
• recovering the mono-[2-(methacryloyloxy)ethyl]phthalate.

A process comprising the steps of:

• mixing 15-25 parts by weight 2-hydroxyethy methacrylate (HEMA) and at least one member of the group consisting of 1-3 parts by weight 2,6-di-tert-butyl-4-((dimethylamino)methyl)phenol or 0.2-2 parts by weight 2,4,6-tris((dimethylamino)methyl)phenol;
• heating the mixture to a set point of 70-100° C. with NOx sparge and then adding 10-30 parts by weight phthalic anhydride to the heated mixture;
• after adding the phthalic anhydride then heating the reaction mixture at 70-90° C. to form mono-[2-(methacryloyloxy)ethyl]phthalate;
• and
• recovering the mono-[2-(methacryloyloxy)ethyl]phthalate.