A New Process for Manufacturing Straw Particleboard by Impregnating and Enzyme Treatment

However, the wheat straw surface was difficult to be penetrated by adhesive due to the wax layer existed on its surface. It is a key point that how to manufacture straw particleboard with traditional resin. This paper explored a novel method to solve this problem by pre-treating straw particles with enzyme and impregnating with resin. Different from conventional spray application, straw was impregnated with phenolic resin (PF). Part of these straws was pretreated with xylanase and lipase before impreanating to improve the bonding between adhesive and straw. The results indicated that when straw was pretreated with lipase and and then applied 10% PF by impregnating, the properties of wheat straw particleboard were optimal, bending strength was 13.81 MPa, elastic modulus was 2.67GPa, internal bond strength was 0.113MPa and 2h thickness swelling was 16.74%.

Preparation of Particleboard Made from Wheat Straw with Low-Formaldehyde-Emission Composite Adhesive

This research attempted to prepare the E0 type wheat straw particleboards with low emission formaldehyde composite adhesive. The composite adhesive combined UF resin and blocked polyisocyanate with low deblocked temperature was synthesized with sodium bisulphate as blocking agent. The effects of different blocking agents, mol ratio, reaction temperature and time on block reaction were studied. The influence of mixed ratio of composite adhesive on the performance of wheat straw particleboard was investigated.

Mechanical Properties of Wheat Straw Particleboard Using Composite Adhesives

The purpose of the study was to use a cheap wheat straw to manufacture particleboard. Wheat straws offer great promise and new challenges as replacement for wood in processed wood products. The particleboard was produced using composite adhesive which the urea-formaldehyde (UF) adhesives modified by emulsifiable polymeric methylene diphenyl diisocyanate (EPU). The properties of the particleboard was evaluated by measuring internal bonding strength(IB), thickness swelling, modulus of rupture(MOR), modulus of elasticity (MOE) and formaldehyde emission. The optimal condition was chosen at density of 0.75g/cm3, UF/EPU ratio of 70/30, adhesive amounts of 10% based on the dry amounts of wheat straw. The test results showed that maximum dry internal bonding strength, wetting internal bonding strength, modulus of rupture, modulus of elasticity was 0.45MPa, 0.072MPa, 31.50MPa and 4564MPa, respectively. The thickness swelling (TS2h) and thickness swelling (TS24h) was 3.51% and 11.1%, respectively. The free formaldehyde of wheat straw particleboard reached E0-type national standards.