High Temperature Hot-Water Treatment Of Bamboo Bundle Raw Materials And The Board Performance Study

Bamboo plywood industry is developing faster and faster in our country,the bamboo integrated timber and the reconstituted bamboo lumber is especially attention and developing rapidly.High temperature Hot-water treatment is a way which is simple?green and non-pollution,it can improve the dimensional stability ? corrosion and the biological durability of outdoor reconstituted bamboo lumber,and the physical performance is good after the modification,Hot-water treatment is a new physical modification methods with development potential.Get a appropriate Hot-water treatment process parameter in the production of reconstituted bamboo lumber,help to promote the use of the outdoors reconstituted bamboo lumber.With the increasingly lack of wood resources,using bamboo replace the wood,which is advocated by China.The article mainly to restructure the bamboo raw material bamboo beam unit as the research object.Using different Hot-water treatment temperature(120??140??160?)and different Hot-water treatment duration(30min?60min?90min?120min)to the bamboo material beam unit with high temperature treatment.And studying the characteristics of raw materials,analysis the changes of the chemical composition content ?thermal stability?infrared spectra of the raw material;then make the bamboo bundle impregnated the phenolic resin,compressed into reconstituted bamboo plate,And analysis the change rule of physical and mechanical properties of reconstituted bamboo lumber,the main conclusions are as follows:(1)With the increase of Hot-water treatment,bamboo bundle's alpha-cellulose holocellulose content shows the tendency of decline,and the content of lignin increase with the increase of Hot-water treatment temperature,under the condition of temperature is 160?,duration is60 min,bamboo bundle's cellulose content dropped 14.19% compared with the untreated sample,Hot-water treatment duration for bamboo bundle materials of mainly chemical composition change trend is much the same as Hot-water treatment temperature bamboo bundle materials of mainly chemical composition change trend,and Hot-water treatment duration for bamboo bundle materials mainly chemical composition change is not significant.(2)Through the Hot-water treatment,bamboo bundle's thermal stability improved;In the infrared spectrogram,bamboo bundle's chemical functional groups is unchanged essentially,but there is a difference in content;Under the scanning electron microscope,the bamboo bundle withHot-water treatment have a bigger surface damage compared to the the bamboo bundle without Hot-water treatment.(3)With the increase of Hot-water treatment temperature and duration,the MOR and Horizontal shear strength of reconstituted bamboo lumber is decline,but the Hot-water treatment temperature and duration for the MOE of the reconstituted bamboo lumber is not very significant.Under the condition of 160?,60 min,the MOR of reconstituted bamboo lumber is89.62 MPa,compared with the untreated reconstituted bamboo lumber,it decreased by 35.25%;The biggest drop in horizontal shear strength of reconstituted bamboo lumber can reach 22.83%.The MOE of reconstituted bamboo lumber generally maintained between 10000 MPa to 12200 MPa.(4)With the increase of Hot-water treatment temperature and duration,the water absorption and thickness swelling of reconstituted bamboo lumber is decline.Under the condition of 160?,60 min,the thickness swelling is 1.67%,and the water absorption of reconstituted bamboo lumber is 6.13%,compared with the untreated reconstituted bamboo lumber,the water absorption and thickness swelling decreased by 53% and 14%.Hot-water treatment temperature compared with Hot-water treatment duration on the influence of water absorption and thickness swelling of reconstituted bamboo lumber is bigger.Surface contact angle analysis showed that,after the Hot-water treatment,the surface contact angle of reconstituted bamboo lumber became big,and the wettability weakened.