This review is composed of three main parts each of which is written by well-known top specialists that have been,in a way or other,also the main participants of the majority of the developments reported.Thus,after a ...This review is composed of three main parts each of which is written by well-known top specialists that have been,in a way or other,also the main participants of the majority of the developments reported.Thus,after a general part covering the grand lines and more in-depth views of more recent tannin,lignin,carbohydrate and soy bioadhesives,somemix of the other bio raw materials with soy protein and soy flour and some other differently sourced bioadhesives for wood,this review presents a more in-depth part on starch-based wood adhesives and a more indepth part covering plant protein-based adhesives.It must be kept in mind that the review is focused on completely or almost completely biosourced adhesives,the fashionable adhesives derived from mixes of biosourced materials with synthetic resins having been intentionally excluded.This choice was made as the latter constitute only an intermediate interval,possibly temporary if even for a somewhat long times,towards a final full bioeconomy of scale in this field.This review also focuses on more recent results,mainly obtained in the last 10–20 years,thus on adhesive formulations really innovative and sometimes even non-traditional.In all these fields there is still a lot of possibility of innovation for relevant formulation as this field is still in rapid growth.展开更多
The main raw material utilized in wood adhesives comes from petrochemical extractives.However,due to the excessive dependence on petrochemical resources and the adverse impact on the ecosystem and human wellbeing,ther...The main raw material utilized in wood adhesives comes from petrochemical extractives.However,due to the excessive dependence on petrochemical resources and the adverse impact on the ecosystem and human wellbeing,there is an increasing trend to develop byproduct protein-based adhesives in the current global food safety context.In this research,flaxseed meal was subjected to pretreatment,and trimethylolpropane triglycidyl ether(TTE)and ethylenediamine(EN)were utilized as crosslinkers to establish a more compact adhesive layer and to prevent water intrusion.The pretreatment decreased the FM/UB viscosity by 60%compared to FM.The combination of CD analysis indicated that the Urea-NaOH pretreatment effectively stretched the flaxseed meal protein.According to Fourier transform infrared(FTIR)spectroscopy,X-ray diffraction(XRD),and differential scanning calorimetry(DSC)were used to analyze the resulting adhesive’s reaction mechanism and thermal response.Furthermore,the physical properties of the adhesive were characterized using wet shear strength testing and SEM observation.Remarkably,the dry bond strength increased from 0.72 to 2.12 MPa,representing a 194.4%increase.The wet bonding strength of the adhesive was improved from 0.22 to 1.21 MPa,representing a 550%increase compared to the original flaxseed protein-based adhesive,which far exceeded the minimum requirement for plywood of Type II(≥0.7 MPa,by GB/T 9846-2015).This study demonstrated an eco-friendly and sustainable method for the development of protein adhesives as viable substitutes for petrochemical resins.展开更多
文摘This review is composed of three main parts each of which is written by well-known top specialists that have been,in a way or other,also the main participants of the majority of the developments reported.Thus,after a general part covering the grand lines and more in-depth views of more recent tannin,lignin,carbohydrate and soy bioadhesives,somemix of the other bio raw materials with soy protein and soy flour and some other differently sourced bioadhesives for wood,this review presents a more in-depth part on starch-based wood adhesives and a more indepth part covering plant protein-based adhesives.It must be kept in mind that the review is focused on completely or almost completely biosourced adhesives,the fashionable adhesives derived from mixes of biosourced materials with synthetic resins having been intentionally excluded.This choice was made as the latter constitute only an intermediate interval,possibly temporary if even for a somewhat long times,towards a final full bioeconomy of scale in this field.This review also focuses on more recent results,mainly obtained in the last 10–20 years,thus on adhesive formulations really innovative and sometimes even non-traditional.In all these fields there is still a lot of possibility of innovation for relevant formulation as this field is still in rapid growth.
文摘The main raw material utilized in wood adhesives comes from petrochemical extractives.However,due to the excessive dependence on petrochemical resources and the adverse impact on the ecosystem and human wellbeing,there is an increasing trend to develop byproduct protein-based adhesives in the current global food safety context.In this research,flaxseed meal was subjected to pretreatment,and trimethylolpropane triglycidyl ether(TTE)and ethylenediamine(EN)were utilized as crosslinkers to establish a more compact adhesive layer and to prevent water intrusion.The pretreatment decreased the FM/UB viscosity by 60%compared to FM.The combination of CD analysis indicated that the Urea-NaOH pretreatment effectively stretched the flaxseed meal protein.According to Fourier transform infrared(FTIR)spectroscopy,X-ray diffraction(XRD),and differential scanning calorimetry(DSC)were used to analyze the resulting adhesive’s reaction mechanism and thermal response.Furthermore,the physical properties of the adhesive were characterized using wet shear strength testing and SEM observation.Remarkably,the dry bond strength increased from 0.72 to 2.12 MPa,representing a 194.4%increase.The wet bonding strength of the adhesive was improved from 0.22 to 1.21 MPa,representing a 550%increase compared to the original flaxseed protein-based adhesive,which far exceeded the minimum requirement for plywood of Type II(≥0.7 MPa,by GB/T 9846-2015).This study demonstrated an eco-friendly and sustainable method for the development of protein adhesives as viable substitutes for petrochemical resins.