摘要 |
<p>A phenol-formaldehyde resole resin is prepared using a high level of catalyst at a polymerization temperature of about 63° C. The endpoint, measured by salt water tolerance, is selected so that the resulting resin has a water dilutability of 20:1 at neutral pH after storage for three weeks at a temperature of about 13° C., with a free phenol level of no more than 0.50 percent.</p> |