Microwave-assisted polyol liquefication from bamboo for bio-polyurethane foams fabrication

In this study, the bamboo powder was liquified under microwave conditions and utilized as a bio-polyol (B-polyol) to synthesize bio-based polyurethane foam (B-PUf). The NMR spectra and GC/MS results showed that the B-polyol mainly comprised carbon derivatives including sugars, phenolic compounds, and other compounds such as ethers and esters. The morphology of B-PUf showed a heterogeneous with a cell size range of 400 − 600 µm and a density lower than 34 kg/m3. The lignin derivatives in B-polyol contributed significantly to improving the thermal stability of B-PUf with a temperature range of 370 − 800 °C. The blocks of B-PUf with 50 × 50 × 25 mm were prepared and burned for flame retardance assessment. These results obtained from this study allow to explain how bamboo can be used as a great potential alternative to fossil fuel and boost the bio-based content in PU foam materials.