摘要 |
The present invention is directed to a method of producing phenolic foams comprising introducing into a substantially closed volume a phenolic resole resin foamable composition and allowing the composition to foam in this volume wherein a pressure in excess of ambient atmospheric pressure is achieved within this volume. This pressure in excess of ambient atmospheric pressure generally is in excess of about 2 pounds per square inch, typically in excess of about 5 pounds per square inch, and preferably in excess of about 6 pounds per square inch, gauge pressure. The present invention is also directed to foams produced by the method of the invention. |