摘要 |
Latex spray foams formed from a two-part foamable composition are provided. The A-side contains a functionalized latex and an acid and the B-side contains a polyfunctional aziridine crosslinking agent, a plasticizer, a base, and, optionally, a non-functionalized resin. The acid and the base form a blowing agent package that when mixed, react to form a gas. The A- and B-side also contain thickening agents. The polyfunctional aziridine crosslinking agent is diluted by a plasticizer, which reduces the viscosity of the B-side and reduces the amount of ethyleneimine, a toxic component in the polyfunctional aziridine crosslinking agent. The presence of a plasticizer also permits the inclusion of other materials that may add functionality and/or cost savings to the foamed product. The plasticizer should have no acidic protons to react with the crosslinking agent. When no acidic protons are present, the B-side is stable for extended periods of time.
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