Synthetic Process of Bio-Based Phenol Formaldehyde Adhesive Derived from Demethylated Wheat Straw Alkali Lignin and Its Curing Behavior  

作　　者：Yan Song Zhixin Wang Xin Zhang Rong Zhang Jinchun Li 

机构地区：[1]Faculty of Materials Science&Engineering,Changzhou University,Changzhou,213164,China [2]Jiangsu Key Laboratory of Environmentally Friendly Polymeric Materials,School of Materials Science and Engineering,Changzhou University,Changzhou,213164,China [3]Organization Department of the Party Committee,Changshu Institute of Technology,Changshu,215500,China [4]School of Petrochemical Engineering,Changzhou University,Changzhou,213164,China

出　　处：《Journal of Renewable Materials》2021年第5期943-957,共15页可再生材料杂志（英文）

基　　金：This work was supported by the National Natural Science Foundation of China(51473024);by University Science Research General Project of Jiangsu Province(16KJD430001)。

摘　　要：Lignin is a natural biopolymer with a complex three-dimensional network, commercially obtained from wasteliquid of paper pulp and bioethanol production, and could be a candidate for preparation of environment-friendlybio-based polyphenol material. In the present work, the demethylated wheat straw alkali lignin (D-Lig), preparedby demethylation of wheat straw alkali lignin (Lig) using an in-situ generated Lewis acid, was used to synthesizebio-based phenol formaldehyde resin adhesive (D-LPF) applied in plywood. Effects of synthetic process’s factors,including lignin substitution for phenol, NaOH concentration and molar ratio of formaldehyde to phenol, on thebonding strength and free formaldehyde content of D-LPF were investigated in detail, and the optimum syntheticprocess of D-LPF was obtained as following: Lignin substitution for phenol 60%, NaOH concentration 5.0% andmolar ratio of formaldehyde to phenol 2.0, and under the optimum reaction condition, the D-LPF presented lower free formaldehyde content (0.18%) and higher bonding strength (2.19 MPa), which was better than those ofcontaining-lignin phenol formaldehyde resin adhesive (LPF). Additionally, the curing behavior of the adhesivewas studied by differential scanning calorimetry (DSC) combined with gel time. It can be obtained that D-LPFresin adhesive had the shortest gel time, and fastest curing rate, compared with those of PF and L-PF resin adhesives. The curing kinetics data was fitted well by Kissinger model using non-isothermal DSC method, and theaverage activation energy value was 85.3 kJ/mol, slightly higher than that of commercial PF resin, while lowerthan that of LPF (90.2 kJ/mol). Finally, based on the analytical results of high temperature fourier transform infrared spectroscopy (FTIR), a possible curing mechanism of D-LPF was proposed.

关 键 词：LIGNIN DEMETHYLATION phenol-formaldehyde resin biobased adhesive synthetic process curing behavior 

分 类 号：O64[理学—物理化学]