Preparation And Characterization Of Anti-photodegradation Bamboo Scrimber

Bamboo scrimber is one of the major industrial products of bamboo industry development in our country.Bamboo scrimberbecame one of the representation of the product in bamboo industrialization along with beauty China and ecological civilization construction in China.The study on production and application technology of bamboo scrimber,has important theoretical significance and practical value on expandingapplication fields andpromotionthe development in the direction of high efficiency and high added value of bamboo scrimber.When bamboo scrimber is exposed to outdoor conditions that result in weathering,such as solar radiation,moisture,oxygen,its physical and mechanical propertiestends to undergo decline.Therefore,it result inlimit of bamboo scrimber application field and reducing of service life.Because of the shortage of outdoor application of bamboo scrimber,this study developeda kind of anti-photodegradation bamboo scrimber which composed by a new outdoor bamboo scrimber and anultraviolet shielding system.The investigation of outdoor bamboo scrimber mainly research the optimization of density and heat treatment parameter.Ultraviolet shielding system was formed by BTZ-1,ethyl acetate,andanhydrous alcohol and film-forming material.The UV-permeability and method ofregulation and control the degree of UV-permeability were investigated in this study.FTIR,UV-Vis spectrophotometer,SEM,TGA/DSC and MS were used to investigate production method and characterization of anti-photodegradation bamboo scrimber.The main results of this study are summarized below.1.The density of bamboo scrimber had significant impact on itsphysical and mechanical properties and ultraviolet resistant performance.Themechanical properties,color stability,wettabilitystability during aging,andrelative roughness parameterincrease with increasing density.Meanwhiledimensional stability showed reversed results.Hence,it existedadvantages and disadvantages with increasing the density of bamboo scrimber.The 1.1 g/cm3 is the best choice for outdoor utilization bamboo scrimber under an overall consideration.2.The result of the influence of heat treatment on lignin properties indicated that the better resistance of heat treated bamboo scrimber to solar radiation was attributed to the less UV attack of lignin.This results could be used for heat treatment optimization of bamboo scrimber.Heat treatment temperature and duration were important factors that influence mass loss,color,UV absorption,and molecular structure of lignin.A positive correlation between certain properties(mass loss and color)of lignin and heat treatment temperature or duration was noticed,whereas a negative relationship was observed with regard to UV absorption.The molecular structure of lignin also changed with increasing temperature or duration of heat treatment.Heat treatment also resulted in fragmentation of the lignin molecules,accelerating the process where macromolecules were decomposed into lower-molecular weight compounds.Lower-molecular weight of lignin is easy to loseexposure to water and heat,which result in grey stain.Therefore,the high temperature(220 oC)of heat treatment was not suit for outdoor utilization of bamboo scrimber.The result of this study confirmed the best temperature and duration of heat treatment were 200 oC and 2-4h.3.BTZ-1,ethyl acetate,andanhydrous alcohol and film-forming material were used to form an ultraviolet shielding system(USS,UV radiation-absorbing coatings).The coatings exhibited high UV-A and UV-B absorbances(?99%)and visible-region transmittances(?90%).The coatings reduced their own oxidationassociated with protection substrate.A simple model wasderived topredict absorbance of USS according to the concentration of BTZ-1 and amount of coatings,the shielding of USS could be regulate and controlby the concentration of BTZ-1 and amount of coatings.Critical BTZ-1 loading amount calculated with the obtained datawas determined to be 1.82 ± 0.05 g BTZ-1/m~2.4.A kind of anti-photodegradation bamboo scrimber whichcomposed by a new outdoor bamboo scrimber and anultraviolet shielding system was developed in this study.Theanti-photodegradation bamboo scrimber significantly improvedthe stabilities of color,gloss,and wettability,its color differences and gloss changeonly were the changes of control sample 52% and 53%.The result of ATR confirmed that coatings reduced their own oxidationassociated with protection substrateagain.