Biological Performance of Wood Modified with Orthophthalic Polyester Resin and Styrene
Öz
Aim of study: This study evaluated the improvements in dimensional stability and biological resistance of wood against fungal degradation, and termites by radiation-induced in situ copolymerization of three types of low viscosity-unsaturated polyester resin with styrene.
Material and methods: Radiation polymerization of unsaturated polyester resin with styrene in a viscous system was performed at ambient temperature using gamma (γ)-rays. In the study, water absorption and dimensional stability of the modified wood specimens were first determined. The wood specimens were also tested against decay and mold fungi and termites in laboratory.
Main results: Results after 24-h water immersion of modified wood specimens showed that more than 70% of water repellent effectiveness was obtained in the wood specimens after modifications with the three formulations of tested chemical mixtures; however, the highest anti-swell efficiency values were observed in the specimens treated with the only one type of treating mixtures. Mold resistance tests showed that the treating mixtures tested were not completely inhibited mold growth; however, some improvements in mold scores were seen when compared to control wood specimens. Results showed that after modifications, the specimens showed increased resistance against the fungi and termites considering untreated control specimens.
Highlights: Modifications by styrene and UP resin with different formulations and gamma irradiation greatly improved water absorption and volumetric swell of test specimens in comparison with unmodified control specimens.
Anahtar Kelimeler
Irradiation, Polymerization, Unsaturated polyester, Styrene, Wood, Decay, Termite
Kaynakça
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