Elastomeric polymer compositions for coatings and sealants
View Patent ↗Polymer compositions for elastomeric coatings or sealants provide excellent balance properties between elongation to break, early water resistance, alkaline resistance and adhesion on unpolar substrates. The composition is free of volatile and toxic monomer such as acrylonitrile, or substituted acrylonitrile.
1. A composition comprising an elastomeric vinyl ester-acrylate-acid polymer emulsion consisting essentially of monomers of:
a vinyl ester comprising an alkyl C8-C36 vinyl ester with an alkyl chain selected from the group of octyl, 2-ethyl-hexyl, nonyl, decyl, isodecyl, undecyl, dodecyl, and 3,5,5-trimethyhexyl, or vinyl laurate;
one or both of an alkyl acrylate or methacrylate, each with an alkyl chain of 4 to 12 carbon atoms;
and a monocarboxylic or polycarboxylic acid selected from the group consisting of acrylic acid, methacrylic acid, crotonic acid, itaconic acid, fumaric acid, maleic acid, and combinations thereof,
wherein the polymer composition is free of acrylonitrile, methyl acrylonitrile and styrenic derivatives.
2. The composition of claim 1 , wherein the alkyl C8-C36 vinyl ester comprises from 10 to 25 wt % of the composition and the alkyl acrylate, methacrylate, or both, comprises from 25 to 75 wt % of the composition.
3. The composition of claim 1 wherein the alkyl C8-C36 vinyl ester comprises from 10 to 20 wt % of the composition and the alkyl acrylate, methacrylate, or both, comprises from 30 to 70 wt % of the composition.
4. The composition of claim 1 wherein the vinyl laurate comprises from 10 to 30 wt % of the composition and the alkyl acrylate, methacrylate, or both, comprises from 30 to 70 wt % of the composition.
5. A polymer comprising the composition of claim 1 having a glass transition temperature from −45° C. to +15° C.
6. A binder composition comprising the composition of claim 1 , wherein the binder composition further comprises a photosensitive chemical which can be activated by UV light promoting the crosslinking of an elastomeric coating or sealant.
7. The binder composition of claim 6 wherein the photosensitive chemical comprises 0.01 to 2.0 wt % of a benzophenone derivative based on the weight of the polymer.
8. A coated masonry object comprising, a masonry substrate and an elastomeric coating comprising the composition of claim 1 .
9. A sealing mastic composition comprising the binder composition of claim 6 .
10. The composition of claim 1 , wherein the elastomeric vinyl ester-acrylate-acid polymer emulsion consisting essentially of monomers of butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, acrylic acid, methacrylate acid, and vinyl laurate.