Material and composite analysis of natural-bonded board manufacture from gigantochloa albociliata (buluh madu) fiber / Mohammad Syahir Redzwan Yusoff

The main objective of this study was to investigate the material attributes of young (less 3 years old) and old (above 3 years old) Gigantochloa albociliata (Madu bamboo), and to evaluate some of the composite performance (physical and mechanical properties) of natural-bonded bamboo fiberboard between the age. The comprehensive knowledge of these properties helps 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 differences in term of 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 conduct by using Shimadzu TGA 50 analyzer in accordance to previous research on thermal degradation of bamboo materials. Based on the results, G. albociliata culm exhibited different chemical contents between young and old/matured age, in which, young bamboo showed higher hot water extractives and ash contents compared to old bamboo. On the other hand, old bamboo contained higher alcohol-toluene extractives, holocellulose, α-cellulose and lignin than the young ones. Hence, more resin and possible bamboo gum in old bamboo that is beneficially for natural-bonded composite product. The thermal analysis of extracted bamboo fiber has some indication on the thermal degradation behavior of both young and old bamboo culm. The maximum temperature degradation of young and old bamboos was 413°C and 404°C respectively. Therefore, old bamboo was degraded at the lower temperature compared to young bamboo, which indicates lower thermal stabilities in young bamboo. The composite performance of natural-bonded fiberboard from G. albociliata showed modulus of elasticity (MOE) value of young bamboo sample at 15, 20 and 25 min. pressing time was 655 MPa, 749 MPa, and 925 MPa, respectively, while for old bamboo sample was 1142 MPa, 1605 MPa, 1693 MPa, respectively. Board made from young bamboo fiber/25 min. pressing time and old bamboo fiber/20 and 25 min. pressing time has achieved the minimum requirement of Japanese Industrial Standard (JIS) A5905-2003 in term of MOE. The highest modulus of rupture (MOR) was 16.03 MPa for board made from old bamboo fiber /25 min. pressing time, while the lowest MOR was 4.80 MPa for board made from young bamboo/15 min. pressing time. The MOR of most of the board groups met the minimum requirement of MDF type 5 and type 15 in JIS. Internal bonding (IB) strength of board has a similar trend with MOR, and the IB value obtained for all groups met the minimum JIS requirement. However, all board groups have failed to fulfil the minimum requirement of water absorption (WA) test and thickness swelling test (TS) required by JIS.