
Theses and Dissertations
Issuing Body
Mississippi State University
Advisor
Shmulsky, Rubin
Committee Member
Nikolic, Dragica Jeremic
Committee Member
Barnes, H. Michael
Committee Member
Zhang, Jilei
Committee Member
Ingram, Leonard
Date of Degree
5-3-2019
Original embargo terms
Visible to MSU only for 3 years
Document Type
Dissertation - Open Access
Major
Forest Resources
Degree Name
Doctor of Philosophy
Degree Name
Doctor of Philosophy (Ph.D)
College
College of Forest Resources
College
College of Forest Resources
Department
Department of Sustainable Bioproducts
Department
Department of Sustainable Bioproducts
Abstract
The feasibility of using modified nano-chitosan particles as an environmentally friendly wood preservative agent was investigated in this research. Chitosan nano-particles were prepared from commercially available low molecular weight (LMW) chitosan and its derivative, trimethyl chitosan (TMC). The specific amount of sodium nitrite added to LMW chitosan through depolymerization process indicated the desired chitosan oligomers. Thin layer chromatography (TLC) was done to confirm the formation of chitosan oligomers with degree of polymerization four. Preparation of TMC was done through a quaternization process and Fourier-transform infrared spectroscopy (FTIR) graphs proved the formation of TMC. Sodium tri-poly phosphate (TPP) as a commercial fire retardant was added to these nanoparticles (chitosan oligomers and TMC) to form nanochitosan-TPP particles based on the ionic gelation method. The viscosity of chitosan nanoparticles which were made by chitosan oligomers and TMC were measured by rheometer. The results showed very low viscosity in comparison to LMW chitosan. The final concentration of chitosan oligomers, TMC and TPP in the nano-chitosan-TPP solution to treat wood were 12, 12 and 4.8% respectively. Then, these particles were used to treat southern yellow pine wood through vacuum impregnation process. Mass and volume of samples increased after treatment which means the nano-chitosan-TPP particles penetrated into cell walls. To study the leaching of treated samples, they were soaked to water according to the E11 standard test (AWPA, 2016) and to investigate the fungi resistance of treated samples, they were exposed to brown rot fungus (Gloeophyllum trabeum) and white rot fungus (Trametes versicolor) according to the E10 standard test (AWPA, 2016). Mass loss of the samples was compared to untreated wood controls. The results of leaching and fungi indicated that non quaternized nanochitosan-TPP particles were more effective than quaternized nanochitosan-TPP particles. Measuring the fire resistance and water vapor sorption isotherm of treated samples revealed that there were not any differences among treated and control samples.
URI
https://hdl.handle.net/11668/21228
Recommended Citation
KhademiBami, Laya, "Nano-Chitosan Wood Treatment : A Combined Fire-Retardant and Antifungal Treatment" (2019). Theses and Dissertations. 3260.
https://scholarsjunction.msstate.edu/td/3260
Comments
Nanochitosan particles||Southern yellow pine||Wood preservatives||Decay fungi||Fire retardancy