Low-VOC polyamino alcohols
View Patent ↗A method for adjusting pH in an aqueous coating composition having an initial pH less than 7 by adding to the aqueous coating composition a compound having formula (V) wherein R 2 and R 3 independently are hydrogen, methyl, ethyl, hydroxymethyl, or R 2 and R 3 combine with a carbon to which they are attached to form a five-membered or six-membered saturated carbocyclic ring; R 4 is hydrogen or C 1 -C 4 alkyl; R 5 is hydrogen, methyl, ethyl or hydroxymethyl; R 6 is hydrogen, hydroxyethyl, C 1 -C 10 alkyl or —CH 2 C(R 5 )(N(R 7 ) 2 )CH 2 OH; and R 7 is hydrogen or methyl.
1. A method for adjusting pH in an aqueous coating composition having an initial pH less than 7; said method comprising adding to said aqueous coating composition a compound having formula (V)
wherein R 2 and R 3 independently are hydrogen, methyl, ethyl, hydroxymethyl, or R 2 and R 3 combine with a carbon to which they are attached to form a five-membered or six-membered saturated carbocyclic ring; R 4 is hydrogen or C 1 -C 4 alkyl; R 5 is hydrogen, methyl, ethyl or hydroxymethyl; R 6 is hydrogen, hydroxyethyl, C 1 -C 10 alkyl or —CH 2 C(R 5 )(N(R 7 ) 2 )CH 2 OH; and R 7 is hydrogen or methyl.
2. The method of claim 1 in which R 2 and R 3 independently are methyl or ethyl; R 4 is hydrogen; R 5 is methyl or ethyl; and R 6 is hydrogen or —CH 2 C(R 5 )(NH 2 )CH 2 OH.
3. The method of claim 2 in which the amount of compound (V) is in the range from 10 wt % to 125 wt % of total weight of carboxylic acid groups in the coating composition.
4. The method of claim 2 in which the compound of formula (V) is added to the aqueous coating composition in an amount sufficient to raise pH of the aqueous coating composition to a range from 7.8 to 9.5.