2004 Volume 25 Issue 2 Pages 86-97
Developments of new novolak type phenolic resins (PAPS resins) were succeeded, using a new resin production process called phosphoric acid phase separation reaction. The resins obtained had a narrow molecular dispersion ratio with the low content of monomer and dimer. This process could be applied to various base compounds such as phenol, cresols, bisphenols and alkyl phenols, for synthesizing the corresponding PAPS resins which had a narrow molecular dispersion ratio at each region of low, middle and high molecules. In this article, we introduce the mechanism of the phosphoric acid phase separation reaction, and the characteristic of the PAPS resins which were synthesized from the various base compounds.
