Abstract:

Chitosan,an natural and renewable polymer without toxic and pollution to human beings and environment and the deacetylated derivative of chitin that mainly contain in the crusts of crabs and shrimps, has many good characteristics and used into many fields such as agriculture, medicine, chemistry, etc.. In order to study the mechanism of modification of wood dyeing as dyestuff carrier for fixation, the main wood constituent of Populus tomentosa sapwood pretreated with chitosan and then dyed by acid orange Ⅱ. Degree of dyeing(DD) of main wood constituent and type of chemical linkage between wood and chitosan were determined. The results showed that the degree of dyeing of wood meal, wood meal extracted by benzene-ethanol solution, holecellulose, cellulose, hemicellulose and lignin of P. tomentosa which were dyed by acid dyestuff were significantly increased after pretreated with chitosan. And amino of chitosan bonded with wood components formed ionic bond with sulfonic group under acid condition, which produced sulphonate. So chitosan fixes the dyestuff and improve the dyeing effects as a kind of dyestuff carrier for wood dyeing.

Key words: Chitosan, Populus tomentosa, Acid dyestuff, Wood dyeing