Room temperature crosslinked foam

A two-part foamable spray composition for forming an insulative foam, the composition comprising:

• a first component including:
• (1) a carboxylated acrylic latex, with or without an acrylic solution, the carboxylated acrylic latex present in an amount of 90 to 95% by weight of the first component, and (2) an acid of an acid-base blowing agent package;
• and
• a second component including:
• (1) a base of the acid-base blowing agent package, (2) a plasticizer, and (3) a polyfunctional aziridine that crosslinks at or about room temperature, the polyfunctional aziridine present in an amount of 2.7% to 30% by weight of the second component;
• wherein the polyfunctional aziridine is the only crosslinking agent in the composition;
• wherein a molar ratio of carboxy functional groups of the carboxylated acrylic latex to aziridine functional groups of the polyfunctional aziridine is 0.5:1 to 2:1;
• wherein upon mixing the first component with the second component a reaction of the acid and the base is operable to generate a gas simultaneously with crosslinking of the first component and the polyfunctional aziridine crosslinking agent to form the insulative foam, the insulative foam hardening to achieve an R-value of 3.5° Fft2h/BTU per inch to 8° Fft2h/BTU per inch within two minutes after the first component is contacted with the second component, and
• wherein the insulative foam has a density of 0.5 to 5 pounds per cubic foot.