摘要
Abstract
Acetate lignin(AAL)was degraded by hydrothermal treatment with the aim of increasing its reactive functional group content while regulating its relative molecular weight,and replacing part of phenol with the low-molecular-weight acetate lignin(DAAL)obtained through hydrothermal degradation to prepare lignin-based phenolic(DLPF)resin adhesive.The effects of hydrothermal treatment conditions,such as reaction temperature,reaction time,and alkali dosage,on the molecular weight,phenolic hydroxyl and methoxyl content of acetate lignin were investigated.The effects of lignin hydrothermal degradation on the physical and chemical properties of lignin-based phenolic res-in adhesives,such as woodchip bonding strength,thermal stability,and free formaldehyde content were analyzed.The results showed that when the hydrothermal degradation conditions were 20%alkali content(relative to the lignin mass fraction),reaction temperature of 200℃and reaction time of 150 min,the phenolic hydroxyl content in DAAL was higher and the methoxy content was lower,and the number-aver-age molecular weight decreased from 9 789 to 3 329;the performance of DLPF prepared with degraded lignin was the best,with a woodchip bonding strength of 1.35 MPa,and the free formaldehyde and free phenol contents were 0.11%and 0.54%,respectively.关键词
木质素/水热降解/酚醛树脂/胶黏剂Key words
lignin/hydrothermal degradation/phenolic resin/adhesives分类
轻工纺织
