Modification of nanochitosan with NaCl and surfactant for wood preservative

Abstract

Chitosan is a natural preservative which is really potential termicide to resist attack termites. Chitosan in size nanometers (nanochitosan) is expected to improve the effectiveness of the nature of anti-termite properties. The smaller size of particles has advantage to easily penetrate the wood pores. Nanochitosan was modified with surfactants (polysorbate-20 and polysorbate-80) and NaCl to increase retention and penetration of preservatives and its anti-termite properties. The purpose of this study was to evaluate the effect of surfactant and NaCl on the parameters of preservation tests which included absorption, retention and termite mortality, and particle size data as supporting data. The average value of absorption and retention of preservatives ranged from 105.79-124.43 kg/m3 and 9.18-18.26 kg/m3. The termite mortality was 33.11-46.89 % for 4 weeks of observation. Data were analyzed using variance analysis (ANOVA) to determine the significance of each treatment. It showed that polysorbate had significant effect to the absorption of preservatives and termite mortality while the retention was influenced by the type and concentration of surfactants. The treatments with the various single compounds showed that both surfactants had a significant effect on absorption, whereas polysorbate-20 had a significant effect on all treatment interactions, and NaCl treatment significantly affected the termite mortality. It was thought that he surfactant treatments increased the retention of nanochitosan by hydrophobic interactions whereas the addition of NaCl increased anti-termite properties and made particles smaller and stable which caused in higher retention. In this study, nanochitosan had an average size of 233 - 798 nm.