Enhancing timber quality of Jabon wood (Anthocepalus cadamba) for high quality products by treatment through densification and impregnation with Merbau extractives

Abstract

Jabon wood (Anthocephalus cadamba sp.) is one of fast-grown species planted in Indonesia that has not yet complied with raw material requirements for good quality products. This suggests that the properties enhancement of the wood using natural and eco-friendly material should be investigated. The main aim of this PhD research was to investigate the effect of impregnation using Merbau extractives on the enhancement of wood properties of Jabon (Anthocepllus sp.). The specific objectives of this research study were: 1. To explore the properties of Merbau extractives (ME) and Polymerised Merbau extractives (PME) in relation with its utilisation as impregnating material for Jabon wood. 2. To explore the characteristics of Jabon wood after densification through two-side hot pressing. 3. To evaluate the effectiveness of treatment with Merbau extractives on fixing compressed deformation of Jabon wood after densification.

An exploration and experimental study on the extraction and the polymerisation of ME followed by application study of the polymerised Merbau extractives (PME) was carried out to investigate the major compound of ME and how it can be polymerisedA study of PME has been conducted on Jabon wood to determine the changes of physical, mechanical and chemical properties of treated Jabon wood. The resistance of the wood against termites was also examined.

Results of this study demonstrated that Merbau extractives - after their polymerisation into PME - can be considered a promising material for wood impregnation application. There was an increment of physical and mechanical properties of Jabon wood after the treatment using the PME. The specific gravity was significantly increased from 0.39 to 0.85 (PME22) and from 0.31 to 0.74 (PME33); a very low Set of Recovery (14.82 %) was obtained and the colour of treated Jabon wood was permanently changed. The surface hardness of modified wood samples exhibited higher values by 30.54 % (PME22) and 39.89 (PME33). Shear strength increased by 41.87 and 49.58 % (PME22) and 74.02 and 79.10 % (PME) for radial (T) and tangential (T) sections, respectively. MOE increased by 23.52% (PME22) and by 40.12% (PME33), MOR values increased by 28.50 and 41.19 % after impregnation with PME22 and PME33, respectively. The increment of mechanical properties of treated Jabon wood after impregnation treatment using Polymerised Merbau Extractives was confirmed by FTIR spectra and crystallinity (XRD) analysis. The improvement has also occurred on the wood biological resistance. With the improvement of Jabon wood properties, the utilisation of this species could be extended to high-quality products such as furniture and building components.