| 摘要 |
PURPOSE:To safely obtain the subject foamed article without using fluorocarbons and combustible low-boiling substance and causing environmental pollution by using a specific thermally decomposable organic chemical foaming agent as a foaming agent in combination with a resol-type liquid phenolic resin and an acid hardener. CONSTITUTION:The objective foamed article can be produced by adding an acid hardener and a foaming agent to a resol-type liquid phenolic resin or its modified resin. The foaming agent used in the above process is a thermally decomposable organic chemical foaming agent such as p-toluenesulfonyl hydrazide, p-toluenesulfonylacetone hydrazone, 4,4'-oxybisbenzenesulfonyl hydrazide, azodicarbonamide, dinitrosopentamethylenetetramine and hydrazodicarbonamide. Preferably, the thermally decomposable organic chemical foaming agent is used in combination with a carbonate or a bicarbonate. |
