THE PHYSICAL AND MECHANICAL PROPERTIES OF RUBBERWOOD MODIFIED BY SORBITOL-CITRIC ACID
DOI:
https://doi.org/10.70169/VJFS.1339Keywords:
physical and mechanical properties, sorbitol-citric acid, wood modification, Heat curing methods, partial delignificationAbstract
In this study, partial delignification was performed, followed by modification of rubberwood using sorbitol‑citric acid (SorCA) under two different heat curing procedures: thermal curing (150 oC, 3 hours) and hot press curing (180 oC, 5 minutes). SEM observations on the radial section revealed the formation of SorCA polyesters inside the cell wall and the occlusion of pits, especially in the samples treated by curing by drying; in the hot‑pressed samples, the cells were severely deformed and the cell lumens were compressed. The curing by drying significantly improved dimensional stability, reducing volumetric swelling by 46% compared to untreated wood. The hot pressing method produced a material with a density increase of 71% and a flexural strength (MOR) increase of 42%, but volumetric swelling increased by 20% due to set‑recovery. This study demonstrates that the environmentally friendly SorCA compound has great potential for plantation wood modification, and depending on the treatment method, different application requirements can be met.
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