Preparation And Characterization Of Bamboo Tar-based Phenolic Resin

Traditional phenolic resins have a large yield and wide range of applications for their excellent performances.However,the main substrates for the traditional phenolic resins,phenol and formaldehyde(as a carcinogenic chemical)are toxics and from petroleum-based resources,with the shortcomings of unrenewability during their production.This is deviated to the trends of environmental benign developing,energy saving,and human health protecting.Replacing these expensive poisonous chemicals with cheaper non-toxic biomass resources during the production of phenolic resins is one of the important directions in future resin industry.In this work,the bamboo tar-based phenolic resins have been prepared by replacing the petroleum-based phenol with bamboo tar,which was one of the by-products in bamboo processing.The bamboo tar-furfural thermosetting phenolic resin(R-BTFF)was obtained by copolymerization of bamboo tar and furfural using the catalysis of alkaline,while the bamboo tar-furfural thermoplastic phenolic resin(N-BTFF)was obtained by copolymerization of bamboo tar and furfural using the acid catalysis.Moreover,the bamboo tar-starch phenolic resin was also prepared by copolymerization of bamboo tar and soluble starch using the catalysis of sulfuric acid.The conventional properties of these resins such as structure and thermal characteristics were characterized by Fourier transform infrared spectroscopy(FTIR)and differential scanning calorimetry(DSC).The results showed that the optimized conditions for the polymerization of R-BTFF resin are the reaction temperature 95℃,the reaction time 3 h,the catalyst amount 8%to the bamboo tar(weight)and the weight ratio of bamboo tar to furfural 1:1.The R-BTFF resin had a relatively low curing temperature of 150℃,and the viscosity decreased with the increasing of temperature,with similar performances and structure compared to R-PFF resin.The N-BTFF resin was cured by curing agent hexamethylene tetramine(HMTA)of 12%per resin mass under heated conditions with the curing temperature of 180℃,the curing time of about 4 min,with similar properties and structure compared to R-PFF resin.The prepared bamboo tar-starch resin had structural characteristics of the thermoplastic phenolic resin,with the curing temperature of 195℃,the curing time of about 8 min.The structure and functional groups of bamboo tar-starch resin are similar to those of phenol-starch resin,with longer gel time.The obtained bamboo tar-based phenolc resins in this work have satisfied properties and thus could have potential applications in fields such as chemicals and materials,which could be an alternative way for the comprehensive utilization of bamboo tar.