Abstract:

According to the structure and oxidation mechanism of rosin, the light-colored reaction of polymeric rosin with phenols, phosphite ester, thioester and etc.was studied. The results indicated that n-Dodecanethiol, epoxy soybean oil, SWC-80 were the preferable color-lightening agents for polymeric rosin. Light-colored polymeric rosin named glyceride with Gardner color 2 was prepared by reacting polymeric rosin with color-lightening agent SWC-80 in the presence of Dy_nO_m catalyst. Its acid value was 12.1 mgKOH·g^-1 and softening point was 135 ℃. At the same condition light-colored polymeric rosin named pentaerythritol ester with Gardner color 3 was prepared. Its acid value was 22.1 mgKOH·g^-1 and softening point was 143 ℃.

Key words: polymeric rosin, color-lightening agent, esterification