Preparation of Glue-free Wheat Straw-based Fiberboard with Zero Formaldehyde

Key Laboratory of Environment-Friendly Composite Materials of the State Ethnic Affairs Commission, Gansu Provincial Biomass Function Composites Engineering Research Center, Key Laboratory for Utility of Environment-Friendly Composite Materials and Biomass in University of Gansu Province, Gansu Province Research Center for Basic Sciences of Surface and Interface Chemistry, College of Chemical Engineering, Northwest Minzu University, Lanzhou 730124, China

^* Corresponding author: hgsq@xbmu.edu.cn

Abstract

Glue-free wheat straw-based fiberboard has the advantages of excellent performance, such as no formaldehyde release, being renewable, and being degradable, which presents a novel approach to enhance the utilization value of straw and protect the environment.. In this study, wheat straw was first pre-treated to remove impurities such as wax and silica contained in wheat straw by a 2% sodium hydroxide solution, and further modified by carboxymethylation and acylation to obtain wheat straw fiberboard raw materials with different functional properties. Then, H2O2 was used as the initiator, and the wheat straw fiberboard raw materials were hot-pressed at 100 °C and 140 kg/cm² to prepare glue-free wheat strawbased fiberboard with the bending strength of 95.43 MPa, the impact toughness of 2.68 kJ/m², the tensile strength of 9.2 MPa, the elastic modulus of 1773.03 MPa, and the hardness of 81D. The performances of the prepared glue-free wheat straw-based fiberboard with zero formaldehyde have surpassed that of the general glue-free board and have the potential to replace wood board.