Fabrication and characterization of a novel corn straw/modified ammonium lignosulfonate bio-composite strengthened by polyethylenimine pretreatment

This study focuses on the development of novel bio-composites via the pretreatment of corn straw particles (PCSP) and modified ammonium lignosulfonate (MAL) as a binder. The corn stalk particles (CSP) were pretreated with polyethylenimine (PEI) to enhance compatibility. The effects of PEI dosage on the mechanical properties and dimensional stability were examined, where PEI pretreatment improved the interfacial properties of MAL and CSP considerably. The optimum values of the PCSP/MAL composites complied with the Chinese national standard for load-bearing particleboard. Furthermore, the results confirmed that PEI pretreatment resulted in good surface activity and exhibited a favorable effect on the crystallinity of the PCSP/MAL composites. The storage moduli E′ and tan δ peak of the PCSP/MAL composites were considerably greater than those of the CSP/MAL composites. The fractured morphology of the composites clearly showed that PEI pretreatment improves the interfacial adhesion of MAL and CSP.