摘要 |
This invention relates to the use of methyl formate as an adjuvant in the formation of phenolic foam. The addition of methyl formate to phenol-aldehyde resoles caused a substantial reduction in resole viscosity and thus allows for the processing of resoles which are otherwise too viscous to be foamed. A further advantage of methyl formate as an adjuvant in the formation of phenolic foam is that it also functions as a blowing agent. In its use as a blowing agent, methyl formate is employed in combination with 1,1,2-trichloro-1,2,2-trifluoroethane. Depending upon the nature of the phenolic foaming resin, the use of methyl formate in combination with 1,1,2-trichloro-1,2,2-trifluoroethane as the source of blowing action further provides the advantageous result of allowing for the formation of a phenolic foam of reduced friability. |