| Along with the development of bamboo wood based panel industry, bamboo glued-laminated timber and recombination bamboo timber as a new type material of furnature and decoration had got lots of attention, and also developed quickly. As a method of purely physical modification which environment-friendly, heat treatment had been widely used in the wood industry. Most of bamboo enterprises in our country using the wood heat-treatment for reference, combining the bamboo characters, had developed lots of the heat-treated bamboo products, such as carbonization color bamboo floor, carbonization color bamboo curtain, carbonization color bamboo furniture, carbonization color bamboo mat, carbonization color bamboo tea-things and so on. But our scientific research units and universities and colleges had little research on the changed properties of chemical and physical-mechanical that of heated bamboo. At present, the correlation literatures were next to nothing. However, the development of our bamboo industry was badly in needs of technical support in this field. So the research of the heated bamboo technical not only filled up the black space in the domain, but also guided our bamboo industry.We used economic bamboo- phyllostachys pubescen as object of the study, and heated in the air dielectric. Test specimens were put in the air dry oven, and heated in the setting temperature (100℃,120℃,140℃,160℃,180℃,200℃,220℃)and duration (1 h,2 h,3 h,4h).Through testing the changes of color, chemical composition content, mechanical properties, dimensional stability and surface properties, we studied the effect of different heat treatment on the heated bamboo physical-mechinical properties, and revealed the physical-mechinical properties'disciplinarian of heated bamboo. The main conclusions obtained from the research and analysis was as follows:1. The effect of heated temperature on the main chemical composition content was significant, the effect of duration on holocellulose andα-cellulose was significant, but not for lignin. When the heated temperature below 180℃,the content of holocellulose,α-cellulose and lignin was little change compared with the unheated materials(but when the temperature below 160℃, the holocellulose had a little increase). When the heated temperature above 180℃, With the increasing temperature and duration, the content of holocellulose,α-cellulose had a trend of descend,but the content of lignin gradual increased. The critical change temperature of holocellulose,α-cellulose was 180℃, The critical change temperature of lignin was 200℃.2. With the increasing temperature and duration, the bamboo's mass loss rate had a trend of increase. When heated temperature between 100 and 160℃, the increase of the mass loss rate was slow, below 1.5%. With the increasing temperature, the mass loss rate increased significantly under the temperature of (160-220)℃, the maxmium was 29.04% . The correlation analysis between mass loss rate and the main chemical composition content of holocellulose,α-cellulose indicated that they had significant correlation at 0.01 level, the correlation coefficient were respectively -0.96,-0.92.3. The heated temperature had significant effect on the color of the specimences. When the heated temperature between (100-120)℃, the color of the heated bamboo was yellowish-white; When the heated temperature between (140-160)℃, the color of the heated bamboo was shallow brown; When the heated temperature between (180-200)℃, the color of the heated bamboo was brown; When the heated temperature was 220℃, the color of the heated bamboo was dark brown. the critical change temperature of the vision parameter was 180℃。The effect of heated temperature on the color of chemical component was significant. when the temperature between (100-180)℃, the color of the holocellulose,α-cellulose and lignin was little change compared with the unheated materials.When the temperature was above 180℃, the color of the holocellulose,α-cellulose and lignin was dark with the increasing temperature: the color of the holocellulose andα-cellulose was from white to light yellow, the color of the lignin was from brown to dark brown and black brown.The change of the lignin color was significant most.For this, the cause of color change for the heated bamboo was mostly from the lignin color changing.The E*of bamboo increased with increasing temperature and duration. The correlation analysis between E*and the chemical composition content of holocellulose,α-cellulose, lignin indicated that they had significant correlation at 0.01 level, the correlation coefficient was respectively -0.98,-0.95,0.90.4. The effect of heated temperature on the mechanical of MOR and MOE was significant, but the heated duration had significant effect on the MOR, but not on the MOE. The effect of heated temperature on the MOR and MOE was more than the heated duration. The critical temperature of the effect on MOR was 180℃,when the temperature below 180℃, with the increasing temperature and duration, the MOR was a little trend of increase. When the temperature above 180℃, with the increasing temperature and duration, the MOR declined significantly. The critical temperature of the effect on MOE was 200℃, when the temperature below 200℃, with the increasing temperature and duration, the MOE was a little trend of increase, when the temperature above 200℃, with the increasing temperature and duration, the MOE declined significantly.The correlation analysis between MOR\ MOE and the chemical composition content of holocellulose andα-cellulose indicated that they had significant positive correlation at 0.01 level; this showed that the loss of MOR and MOE had a relation with the degradation of hemicelluloses and cellulose.5. Heat treatment enhanced the dimensional stability of heat-treated bamboo significantly. After heated, the EMC and liner shrinking rate of specimens declined with the increasing temperature and duration.The critical temperature was (180-200)℃.6. The heated temperature had a significant effect on surface properties of the specimens. When heated during (100-180)℃for 4 hours, the wettability was declined with the increasing temperature.
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