Mastic and caulking composite articles

Abstract

Permanently flexible and non-tacky coating mastic and caulking compositions having improved heat-age stability contain (a) at least one polymer having a T.sub.g of about -50.degree. C. to about -10.degree. C. and pendant functional groups attached to the polymer backbone and having the formula: ##STR1## in which R.sub.1 is a divalent organic radical at least 3 atoms in length, and X is organoacyl or cyano; (b) a zinc-containing pigment (e.g. zinc oxide); and (c) a polyphosphate anion in an amount effective for increasing the wet adhesion of the compositions, particularly of aged compositions. The mastics and caulks typically have total non-volatile matter concentrations of about 60 to about 90 weight percent of which about 15 to about 75 weight percent comprises the described polymer and about 25 to about 85 weight percent is the zinc-containing pigment and other non-volatile solid matter other than the polymer such as fillers, other pigments, etc. The liquid portion of the mastics and caulks may be a polymer solvent, aqueous polymer dispersant, or other material. The cured compositions exhibit exceptionally good wet adhesion to architectural structural materials, especially to materials having relatively non-adherent surfaces such as foamed polyurethane roof insulation and smooth surfaced elastomers and plastics, even after heat aging.