Controllable synthesis of the Al₄B₂O₉ nanowhisker and their applications in reinforced polyhydroxyalkanoate composites

Abstract

Large quantities of aluminum borate (Al4B2O9) nanowhiskers have been successfully synthesized by sol–gel and post-thermal-treatment methods.

Characterization of Al18B4O33 ceramic synthesized by the sol‐gel, precipitation, and combustion methods

“…A constant weight is approximately preserved from 800 to 1000°C, however, two exothermal peaks are observed at about 900 and 970°C; likely correspond to the crystallization of Al 4 B 2 O 9 and Al 18 B 4 O 33 phases by the reactions () and (), respectively . It has been shown that the Al 4 B 2 O 9 phase is unstable and is decomposed to Al 18 B 4 O 33 phase and boron oxide at the higher temperature (approximately 1000°C) …”

“…The synthesized powders are single‐phase and none of the impurity diffraction peaks are observed, indicating the high‐purity percentage of Al 18 B 4 O 33 . Finally, the weight loss of 3% happens between 1050 and 1200°C which is related to an endothermal peak at about 1150°C, corresponding to the evaporation of residual boron oxide …”

“…Some properties of Al 4 B 2 O 9 phase are similar to those of Al 18 B 4 O 33 phase. However, the Al 4 B 2 O 9 phase is unstable and is decomposed at high temperature . Tao et al showed that Al 18 B 4 O 33 nanowires also have higher hardness and elastic modulus than Al 4 B 2 O 9 nanowires.…”