摘要 |
One- and two-part spray non-isocyanate foams that include an amide-based oligomer containing pendant carboxylic acid and a polyfunctional aziridine crosslinking agent is provided. The amide oligomer typically contains urea links, urethane links or both groups. Additionally, the foams may include one or more plasticizer, a non-functionalized resin, a surfactant, and/or a thickening agent or rheology modifier. The amide oligomer does not contain any isocyanate groups, and, as a result, there are no free isocyanate moieties generated during formation of the foam that may be potentially hazardous to workers installing the foam. The presence of the urethane segments on the oligomer permits for the generation of a polyurethane foam without the drawbacks of conventional polyurethane foams. The foams may be used to fill cavities, cracks, gaps and crevices, such as around windows and doors, and may also be used in flash and batt systems.
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