EFFECTS OF ELLAGIC ACID AND DERIVATIVES THEREOF ON WATER REPELLENCY AND DIMENSIONAL STABILITY

Abstract

Derivatives of the insoluble polyphenolic ellagic acid and water soluble tetraguanidinium, tetracholine, tetrakis-benzyltrimethylammonium and tetrakis-tetramethylammonium ellagates and 2,3,4,2’,3’,4’-hexamethoxy-6,6’-diisocyanato-diphenyl, were prepared. The effects of these compounds upon water repellency and dimensional stability when impregnated into timber were examined. Water soluble ellagates improved water repellent effectiveness up to 32%. Ellagic acid and 2,3,4,2’,3’,4’- hexamethoxy-6,6’-diisocyanato-diphenyl increased initial swelling rates due to their solvent carriers. All trial compounds provided the timber wafers with additional dimensional stability predominantly by non-bonded, non-leachable bulking. Generally a reduction in the extent but not  the rate of moisture  uptake was noted  for the compounds investigated.