Reactive surfactants for freeze-thaw stable emulsion polymers and coatings thereof
The invention provides aqueous coating composition having freeze thaw stability, comprising: (a) at least one latex polymer derived from at least one monomer and at least one reactive surfactant of the formula R 1 O—(CH 2 CHR 2 O) x —(CH 2 CH 2 O) y —(CH 2 CHR 3 O) z —R 4 where R 1 is either alkyl, aryl, alkylaryl, or aralkylaryl of 8-30 carbon atoms, R 2 is —CH 2 OCH 2 CH═CH 2 (AGE); R 3 is either H, CH 3 , or CH 2 CH 3 ; R 4 is H or —SO3M or —PO3M where M is H or K, Na, NH 4 , NR 4 , alkanolamine, or other cationic species and x=2-100; y=4-200 and z=0-50.
1. A aqueous coating composition having freeze thaw stability, comprising: at least one latex polymer derived from at least one monomer and a combination of a reactive surfactant of the formula:
where R=CH 3 or CH 2 CH 3 , n=1, 2, or 3; x is 2-10, y is 0-200, and z is 4-200;
and a surfactant of the formula:
where n=2, x=20 and M + is NH 4 + .
2. The coating composition of claim 1 having five cycles of freeze-thaw stability.
3. The aqueous coating composition having freeze thaw stability of claim 1 wherein said z of Formula I is 5 to 60.
4. The aqueous coating composition having freeze thaw stability of claim 3 wherein said z of Formula I is 5 to 40.
5. The aqueous coating composition having freeze thaw stability of claim 1 further comprising at least one additional surfactant selected from the group consisting of nonionic, anionic, cationic and zwitterionic surfactants.
6. The aqueous coating composition having freeze thaw stability of claim 1 wherein said n=2.
7. A method for imparting freeze/thaw stability to a latex which method comprises conducting a latex forming polymerization with a surfactant mixture comprising:
(a) a reactive surfactant of the formula
where R=CH 3 or CH 2 CH 3 , n=1, 2, or 3; x is 2-10, y is 0-200, and z is 4-200; and (b) a surfactant of the formula
where n=2, x=20 and M + is NH 4 + .
8. The method of claim 7 wherein said latex has five cycles of freeze-thaw stability.
9. A method for imparting freeze/thaw stability to a latex which method comprises conducting a latex forming polymerization with a surfactant mixture comprising:
(a) a surfactant of the formula
where R=CH 3 or CH 2 CH 3 , n=1, 2, or 3; x is 2-10, y is 0-200, and z is 4-200; Z can be either SO 3 − or PO 3 2− , and M + is Na + , K + , NH 4 + , or an alkanolamine and (b) a surfactant of the formula
where n=3 and x=10.