Biological Degradation by Insects and Marine Organisms

Imamura etal. (1986) exposed particleboard made from acetylated wood to the termite species Coptotermes formosanus and Reticulitermes speratus. A forced feeding test according to the JWPA standard 11-1981, where the untreated or acetylated wood was the only food source, and a choice feeding test (where wood specimens were randomly placed on a termite breeding colony for 30 days) were used. With C. formosanus, there was limited attack of the fully acetylated boards, with about 50 % termite mortality after 3 weeks in forced feeding tests, whereas with R. sparatus there was virtually no attack and 100% mortality. 

Rowell etal. (1987b) produced PF-bonded flakeboard from acetylated southern pine (21.6 % WPG) or aspen (17.6 % WPG) flakes. This was not completely resistant to attack by termites Reticulitermes flavipes) in a 4-week test. It was thought that acetylation was less effective in preventing termite attack than other chemical modifications because cellulose decomposition in the intestines of termites leads to acetic acid formation in any case. 

Yusuf etal. (1989) exposed IS- or PF-bonded particleboard made from acetylated albizzia to C. formosanus according to JWPA standard 12-1981, and in a field test (3 months exposure next to a nest of Coptotermes sp.). In both tests, weight losses were around 50 %, indicating a lack of resistance to attack by this species. 

Hadi etal. (1995) examined the resistance of PF-bonded flakeboards of acetylated rubberwood to attack by dry wood (Cryptotermes cynocephalus) and subterranean 

Pine sapwood acetylated to 22 % WPG exposed for 1 year at an outdoor test site in Indonesia showed a weight loss of only 2 % due to termite attack, whereas unmodified controls lost 93 % in weight in the same period (Westin etal, 2004b). 

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