Moso bamboo (Phyllostachys heterocycla (Carr.) Mitford cv. Pubescens) was subjected to heat treatment with saturated steam at 140, 160, and 180 °C for 10-30 min to evaluate the effects of the treatment on the properties of bamboo. The changes in the physical, mechanical, and chemical properties as well as microscopic structures of moso bamboo were analyzed in this study. Results indicated that its equilibrium moisture content (EMC) decreased gradually after being treated by high-temperature saturated steam mostly due to the hemicelluloses' degradation. Both the temperature and duration of treatment affect the mechanical properties of bamboo. The modulus of elasticity (MOE) of bamboo was prone to be affected by heat treatment with saturated steam as compared to the modulus of rupture (MOR). The MOR and MOE increased as compared to the control when the sample was treated at 140 °C. However, a severe treatment negatively affects the mechanical properties of bamboo. The MOR and MOE decreased by 47% and 20% as compared to the control when the sample was heated at 180 °C for 30 min.

Bamboo vascular bundle fiber and parenchyma (BP) are separated by high-temperature treatment with saturated steam. Bamboo vascular bundle fiber is widely used in the market, but how to develop and utilize parenchyma tissue is a difficult problem. The sulfated cellulose nanofibers (ANFs) were obtained by sulfating BP with a deep eutectic solvent (DES), which provided a theoretical basis for the value-added utilization of BP. Using DES as the reaction medium and reagent, the BP was grafted with a sulfonic acid group to form a gel substance in water, ANFs and nanocellulose gel were obtained by ultrasonic cell crusher. The highest yield of ANFS was 75%. The width of the ANFs was about 3 nm, and a small number of nanofiber aggregates existed at the same time. A high aspect ratio of ANFs, due to their high viscosity, has potential applications as enhancers at low concentrations. Lewis acid (ZnCl 2 ) added based on binary (DES) greatly improved the thermal stability of the ANFs and maintained the crystal form of cellulose I.