Engineering High-Performance and Mold-Resistant Bamboo Fiber-Based Composites from Small-Diameter Bambusa textilis

Small-diameter bamboo is a promising raw material for high-performance composites used in outdoor construction. This study aimed to compare the raw-bamboo characteristics of Bambusa textilis (BT) and Bambusa emeiensis (BE), evaluate processing conditions for BT composites, and assess mold resistance and dimensional stability. BE provided a reference for raw-material characterization and a selected flexural comparison. The tested BT material had a denser vascular-bundle distribution and higher isolated-fiber tensile properties. At a target density of 1.35 g/cm3 and 10% phenol-formaldehyde (PF) loading, BT composites reached a flexural strength of 324 MPa, compared with 234 MPa for BE, a flexural modulus of 33 GPa, and a tensile strength of 358 MPa. Thickness swelling was 3.3% and water absorption approximately 16% after 18 days of room-temperature immersion. In a separate BT series at 1.20 g/cm3 and 20% PF, 21% nominal CMIT/MIT formulation retention prevented visible Botryodiplodia theobromae growth on both evaluated faces and Aspergillus niger growth on the front face; side-face A. niger coverage was 35% at day 28. These results support further development of high-strength BT composites with improved mold resistance.