| 摘要 |
PURPOSE:To obtain a polyamide foam which is lightweight, has a uniform state of foaming and excels in strengths, heat resistance, appearance, etc., by anionically polymerizing an anhydrous lactam in the presence of a blowing agent comprising a specified sulfonyl hydrazone compound. CONSTITUTION:A blowing agent comprising a sulfonyl hydrazone compound having a chemical structure of the formula (wherein n is 1-3; R is a 2-12C aliphatic hydrocarbon group or an aromatic hydrocarbon group; and R<1> and R<2> are each H or a 1-10C hydrocarbon-group) is prepared. Examples of the compounds of the formula include p-toluenesulfonylacetone hydrazone and 4,4'- oxybisbenzenesulfonyl hydrazone. An anhydrous lactam (e.g., caprolactam or valerolactam) is anionically polymerized in the presence of the blowing agent to obtain a polyamide foam. The obtained polyamide foam can be desirably used for automotive parts, electrical components, etc. |
