High overall performance transparent bamboo composite via a lignin-modification strategy

Development of transparent material derived from fast-growing natural bamboo is a promising and sustainable alternative for traditional glass materials. Here, we propose an effective strategy to prepare a transparent bamboo composite via lignin-modification and epoxy infiltration. This lignin-modification method can well maintain the integrity of natural bamboo, which provides a robust framework for the epoxy infiltration. The lignin-modified bamboo shows a high whiteness with significantly reduced light absorbance from 3 to 0.8 compared with natural bamboo. The above two aspects guarantee that the transparent bamboo composite obtained offers a high optical transparency of 87% over the visible wavelength range and a high tensile strength of 118 MPa simultaneously. Compared with conventional glasses, the as-prepared transparent bamboo composite has higher overall performance. Specifically, the transparent bamboo composite demonstrates the following advantages: (1) high optical haze (90%), which is beneficial to creating uniform indoor light distribution; (2) high toughness (4.5 MJ/m3), which is helpful to absorbing energy; (3) low density (1.2 g/cm3), which is good to lowering weight, and (4) low thermal conductivity (around 0.33 W/mK), which is only one third of conventional glasses and good for thermal insulation. The transparent bamboo composite with excellent overall performance has great potential in engineering applications, particularly for energy-efficient buildings.