Solvent liquefaction process is one of the promising techniques for the effective utilization of waste woody biomass. In the liquefaction process, waste woody biomass such as waste bamboo could be converted to liquid reactive materials for developing biomass-based materials since waste bamboo has an advantage of providing the liquefi ed products with a small range of variances. The components of liquefi ed waste bamboo released during the liquefaction reaction with the polyethylene glycol 400 (PEG 400) solvent is highly acidic in the presence of mineral acid catalysts. Therefore, this study was carried out for analyzing the behavior of the liquefi ed residues (LRs) from waste bamboo during the solvent liquefaction process. The LRs produced during the liquefaction process were measured and related to different liquefi ed conditions. The change in the morphological surface of the liquefi ed waste bamboo samples was observed by a scanning electron microscope. The chemical changes in the functional groups were analyzed by a Fourier transform infrared spectrometer. The crystalline structure of liquefi ed waste bamboo samples was determined by X-ray diffraction. The chemical composition analysis and particle size distribution of liquefi ed waste bamboo samples were also carried out to confi rm the results. It was found that the effi ciency of liquefaction process can be improved by increasing the temperature and the amount of acid catalysts, although condensation reaction occurred under the liquefaction condition with high temperature. The liquefaction period of lignin was signifi cantly shorter than one of cellulose in the solvent liquefaction process with PEG 400. Moreover, it is indicated that the progress of liquefaction process may be prevented by smaller particle sizes of cellulose collected in liquefi ed bamboo.

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Bamboo is one of the most significant biomass resources which has been used in houses, flooring, construction of scaffolding and bridges, etc. The solvent liquefaction process is one promising technique for effective utilization of waste bamboo materials for the lignocelluloses which can be converted to liquid reactive materials as biomass-based materials. Bamboo has the advantage of providing liquefied products with a small range of variances. The components of bamboo have high acidity in the presence of mineral acid catalysts and possess constituents which can react with polyethylene glycol 400 (PEG 400). In this study, waste bamboo materials have been used in liquefaction experiments. The liquefaction process and liquefied residue have been measured according to the liquefied conditions and the surface changes of waste bamboo samples observed by a scanning electron microscope. The changes in the functional groups have been analysed by a Fourier transform infrared spectrometer and the behavior of the crystalline structures of liquefied bamboo has been determined by X-ray diffraction. Other experiments, such as the degree of polymerization, have also been carried out to confirm the results. It was found that increments of the temperature and the amount of the acid catalysts improved the efficiency of liquefaction. Meanwhile, the dissolution time of lignin was significantly shorter than that of cellulose in the solvent liquefaction process of PEG 400.

Cellulose and lignin are the main structural polymers in the plant cell wall. Cellulose is the structural component of the primary cell wall of green plants, many forms of algae and the oomycetes. About 40-50% of woody matter is cellulose. Lignin is a highly cross-linked polymer created by the polymerization of substituted phenolic compounds, known as monolignols, such as coniferyl, pcoumaryl, and synapyl alcohol. Liquefaction process is one of the promising techniques for effective utilization of woody biomass for the lignocelluloses can be converted to liquid reactive materials as the bio-based materials. Cellulose would have an advantage of providing liquefied product with small range of variance. The phenolated woody components have high acidity in the presence of mineral acid catalysts and possess the constituents which can react with formaldehyde. In addition, lignin, one of the major woody components including the hydroxyl-benzyl structure, has the potential to react with formaldehyde. However, as its complexity in structure, the liquefaction mechanism and the liquefied products with phenol should be found out to solve some problems such as the reaction efficiency and low molecular weight products, and it will be useful to preparation of bio-based materials thought the liquefaction processes. In our study, two model woody components have been used under the different liquefaction conditions with phenol. In our experiments, the model cellulose component is specially used in the experiment to test the characteristics of the products under different ratios. As the results, we found that the final liquefied products from model component substance of lignin only 17.2% (wt) and the growth rate is very low with the molecular weight (Mw) up to 2119 under the reaction temperature of 150°C and 3 hours in the liquefaction experiments. However, the model cellulose component was confirmed to contribute more. On the contrary, the Mw of raw woody powder material can be reach to 1851. In a series of the mixing experiments, we found that the variation of Mw in the different experimental conditions determined by a gel permeation chromatography. From the results of liquefaction residue, we calculated the activation energy, and compared the value of those in different conditions. The solubility of the phenolated woody powder had been evaluated in eight organic solvents to evaluate the hydrogen bonding strengths of these solvents. It is very helpful for sustainable chemistry if polymeric materials can be effectively produced from the biomass liquefaction processes.