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The objective of this study was to evaluate the chemical contents and thermal stability of young (3 years old or less) and matured (more than 5 years old) Madu Bamboo (Gigantochloa albociliata). The comprehensive knowledge of these properties will help to promote the uses of this bamboo’s fiber for natural-bonded composite products. The different age levels of bamboo can be an indicator in evaluating the significant difference of the chemical contents and thermal stability of bamboo. The chemical contents were determined in accordance to the standard outline in Technical Association of Pulp and Paper Industry (TAPPI) test method, while thermal stability was conducted in accordance to Shimadzu TGA 50 analyzer. The culm exhibited different chemical contents between young and old age, in which, young bamboo showed higher hot water extractives and ash contents compared to mature bamboo. On the other hand, matured bamboo contained higher alcohol-toluene extractives, holocellulose, a-cellulose and lignin than young ones. Hence, more resin and possible wood gum in matured bamboo that is beneficially in natural bonded composite product. The thermal analysis of extracted bamboo fiber indicated the thermal degradation behavior of both young and matured bamboo with the same species. The maximum temperature degradation of both young and matured bamboos was 413°C and 404°C. Therefore, matured bamboo was degraded at lower temperature compared to young bamboo, which indicates lower thermal stabilities. The result of this study reported that young bamboo of G. albociliata species is acceptable to be harvested at young ages for reinforcement in natural bonded composite board, according to their thermal stabilities and chemical contents.

also reduced the T −5% values, assignable to bamboo particle degradation caused by the high processing temperatures. For oxidative induction time (OIT) testing, only granules and CMB from pure PVC composites system showed measurable oxidative times compared with OIT profiles of PVC/B. vulgaris composites system, suggestive of comparatively stabilized thermoplastic composites. This revealed that processing with bamboo particles does not contribute to degradation of PVC composites.

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Forest inventory data were collected from five transect lines divided into 20 m × 20 m sampling plots in a lowland rainforests of Kuala Keniam, Pahang National Park, Malaysia. All trees of greater than 10 cm in diameter at breast height (DBH) were measured and identified by species. A total of 448 stems, 198 species, 116 genera and 44 families occurred in study area, in which dominant families include Euphorbiaceae, Myristicaceae, Burseraceae, Leguminosae and Myrtaceae. Tree species such as Elateriospermum tapos, Knema patentinervia, Macaranga lowii, Mallotus leucodermis and Syzygium spp. are among the important part of the floristic composition in the study site. There were no significance differences in the means of basal area, stems, species and genera per hectare between five transects (P≥0.05), indicating that the forest is characterized by a uniform spatial distribution of trees. However, the sites are represented by different combinations of the dominants and co-dominant species. The Shannon-Weiner species diversity index (H') ranged from 3.42 -3.97, which is within the range of other studies in lowland rainforests. The stand structure described by diameter distribution was inverse J-shaped which indicates the stands are developing and regeneration in the forest is present. The results from this study are expected to be helpful in providing a valuable reference and encouraging positive participation in biodiversity conservation.

Analysis of particles size distribution of Malaysian bamboo species (Bambusa vulgaris and Schizostachyum brachycladum) for polyvinyl chloride (PVC) composites production was conducted using dynamic image analysis (DIA). A wide distribution of bamboo particles length was recorded, varying from almost 0 to 1500-µm for both species. Inadequate amount of actual particles length distribution from each sieve size (75-µm and 1-mm) was also recorded. DIA observed an increase of aspect ratio from small to large particles, and fine particles were recorded to be slightly elongated than the large ones. However, the effects of bamboo particles size on the finished PVC composites performance were uncertain, considerable of numerous other factors that influence the performance. Only impact and water uptake properties of composites have been obviously affected by different particles size. Greater modulus value is observed in composites with high particles loading, though low impact strength and water resistance were recorded. The incorporation of high concentration of selected processing lubricants in the composites formulation helped to improve the impact and water resistance of the composites. Malaysian bamboo particles-PVC composites performance between different species was equivalent, demonstrated that both species displayed identical behaviour for composites production.

In this study, rice straw and bagasse are used as raw materials to produce binderless particleboard (BPB). This study aims to evaluate the mechanical and physical properties of BPB. We identify the raw material that would be better for the production of BPB from the viewpoint of their basic properties. The BPBs are made from rice straw, bagasse, and combinations of both in ratios of 50:50 and 40:60, respectively. The modulus of elasticity (MOE), modulus of rupture (MOR), internal bonding (IB) strength, water absorption, and thickness swelling properties of the different BPBs are determined and compared. Results showed that all the properties are significantly influenced by the type of particles or particle combinations in the BPB. BPBs made from bagasse alone have the highest MOR, MOE, and IB mean values, whereas BPBs made from rice straw alone exhibit the lowest MOR, MOE, and IB values. Meanwhile, BPBs made from a combination of rice straw and bagasse at 40:60 ratio by weight have the second highest values for properties such as MOR, MOE, and IB, followed by BPBs made from a combination of rice straw and bagasse at 50:50 ratio by weight.

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