Ambient temperature curing polymer compositions containing acetoacetoxyethyl methacrylate, glycidyl methacrylate and a polymerizable acid

#The field of art to which this invention pertains is coating compositions which cure at ambient temperatures.

#Coating compositions which cure under ambient conditions have been known for a long time. The earliest of such coating compositions are coatings based on drying oils which cure by air oxidation. Other coating compositions which have been developed more recently are those based on the epoxide-carboxylic acid reaction, isocyanate-moisture reaction, polyaziridine-carboxylic acid reaction, and activated methylene-unsaturated acrylic reaction.

#In U.S. Pat. No. 3,554,987, film forming interpolymers of acrylic acid, acetoacetoxyethyl methacrylate and monomers copolymerized therewith are described.

#To a suitable reactor fitted with two dropping funnels, condenser, agitator and thermometer were added 355 parts of water, 1.95 parts sodium bicarbonate and 9.83 parts of phosphated nonyl phenyl polyethylene glycol ether surfactant. To one dropping funnel were added 111.45 parts of methylmethacrylate, 128.57 parts of butyl acrylate, 10 parts of acetoacetoxyethyl methacrylate, 7.5 parts of acrylic acid and 22.5 parts of glycidyl methacrylate. To the other dropping funnel were added 40.43 parts of water and 1.13 parts of ammonium peroxy disulfate. Agitation was begun and heat was applied raising the temperature in the reactor to 85.degree. C. An initial charge of 0.06 part of ammonium peroxydisulfate in 19.5 parts of water was made to the reactor and the slow addition of monomers and catalyst was begun. While keeping the temperature at 85.degree. C., the monomers were added over 2 hours and the catalyst over 2 hours and 5 minutes. The temperature was lowered to 70.degree. C. and 0.3 part of t-butylhydroperoxide was added. The temperature was then lowered to 35.degree. C. and a solution of 0.3 part of sodium formaldehyde sulfoxylate in 9.89 parts of water was added. When the temperature reached 25.degree. C., 4.89 parts of 28 percent ammonium hydroxide and 1.18 parts of a microbiostat were added. The resulting stable latex had a viscosity of 25 cps, a solids content of 40.45 percent and a pH of 5.2.

#The pH of a portion of the latex was adjusted with ammonia to 7.5 and then with sodium hydroxide to 9.0. (Ex 1A). Another portion had the pH adjusted to 9.0 with tetramethyl ammonium hydroxide (Ex 1B). Films were drawn down on glass panels and were left under ambient conditions for 48 hours. The films were removed from the substrate and tested with the results shown in Table 2.

#Using the same procedure described in Example 1, 143.76 parts of methyl methacrylate, 165.79 parts of butyl acrylate, 9.03 parts of methacrylic acid, 14.45 parts of acetoacetoxyethyl methacrylate and 28.9 parts of glycidyl methacrylate were polymerized. The resulting latex had a viscosity of 1100 cps and a solids content of 47.32 percent. The pH of the latex was adjusted to 9.0 with tetramethyl ammonium hydroxide. Films were drawn down on glass panels and were left at ambient conditions for 48 hours. The film withstood 108 methyl ethyl ketone double rub. The results of other film tests are shown in Table 2.