HOMOLYTIC CLEAVAGE OF THE BETA-ETHER BOND IN PHENOLIC BETA-O-4 STRUCTURES IN WOOD LIGNIN AND IN GUAIACYLGLYCEROL-BETA-GUAIACYL ETHER

The degradation of guaiacylglycerol-beta-guaiacyl ether and lignin in spruce wood was studied in order to investigate the extent of homolyti c reactions on heating with dioxane: water media (''mild hydrolysis'') . The degradation reactions were studied at different temperatures, re action times and pH-values. The results clearly show that extensive cl eavage of phenolic beta-ethers occur under the conditions prevailing d uring heating in dioxane:water media. Homolytic cleavage of phenolic b eta-ethers should therefore be considered in interpretations of result s from ''mild hydrolysis'' of lignin.