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Sweet sorghum bagasse (SSB) and citric acid (CA) were used as sustainable raw materials in the development of environmentally friendly particleboard. Sucrose was added to improve the mechanical and physical properties of the particleboard. The effects of the weight ratio between CA and sucrose on the physical properties of the particleboards were investigated. The mechanical properties of particleboards bonded with adhesives at 15/85 and 10/90 wt.% ratios of CA to sucrose were superior to particleboard with other ratios. The thickness swelling of the particleboard increased with an increasing sucrose ratio. Moreover, the physical properties of the particleboard were comparable to those of particleboard bonded using phenol formaldehyde (PF) resin and satisfied the requirements of the type 18 JIS A 5908 (2003) standard. Also, the brittleness of the particleboard was decreased by adding sucrose. Low formaldehyde emission and biological durability against termites and decay were obtained by particleboard under suitable ratios of CA to sucrose. According to the results from thermal analysis and infrared spectra measurement, reactions leading to ester linkages occurred among the CA, sucrose, and SSB components.

The Indo-Malayan drywood termite, Cryptotermes cynocephalus (Light) (Kalotermitidae), is considered one of the most invasive drywood termites in the Southeast Asian region. Once infesting a timber, the colony of a drywood termite is very difficult to be controlled. Thus, the best way to mitigate a new infestation of a drywood termite is by applying chemical protection on wood. In recent years, particular attention has been given by researchers to develop and use organic termiticides, such as essential oils extracted from plants as active ingredients. The objective of the present study is to evaluate the repellency performance of several economically important essential oils from Indonesia, such as Clove (Eugenia caryophyllata), Cubeb Pepper (Piper cubeba L), and Lemon Grass (Cymbopogon winterianus Jowitt) against a drywood termite, C. cynocephalus. The test was performed by subjecting various concentrations of essential oil toward C. cynocephalus in the force-feeding test method. Sample weight-loss was evaluated after two weeks test. The results suggested that Clove oil has the highest repellence performance against C. cynocephalus, followed by Lemon Grass and Cubeb Pepper oils. The Termite mortality rate was also recorded to understand the toxicity performance of those essential oils.

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