Mechanical and interfacial properties of phenolic composites reinforced with treated cellulose fibers

Morphologies and compression performance of graphene oxide/SiO2 modified phenolic foam

In this study, the graphene oxide/SiO2 hybrid materials with different sizes (GO/SiO2-80, GO/SiO2-170, GO/SiO2-250) were prepared via in situ preparation. Different sizes and weight fraction of GO/SiO2 were added into phenolic resin to prepare phenolic foam composites. The cell properties, morphologies, and mechanism of GO/SiO2 reinforced PF composites were studied. The results showed that the GO/SiO2-80 can improve the cell structure and compressive property obviously than other size nanoparticles. The PF modified with 1 wt% GO/SiO2-80 exhibited most uniform cell structure, and it showed a mean cell size of 117 µm and narrow cell size distribution from 50 µm to 225 µm. The obtained PF/(1 wt% GO/SiO2-80) also showed an excellent compressive strength and modulus of 0.18 and 3.22 MPa, which has increased by 80% and 61%, respectively, compared to the pure PF. This method may make it possible for using GO/SiO2 hybrid materials to enhance the cell structure and compression performance of the phenolic foam composites with broader applications.

Effect of compatibilizer on the properties of PBS/lignin composites prepared via a vane extruder

Maleic anhydride (MAH) grafted polymers and silanes have been used as the compatibilizer in poly (butylene succinate)/lignin (PBS/lignin) composites. Compatibilized composites were fabricated by a novel vane extruder (VE). The effects of MAH grafted and coupling agent on the mechanical, thermal property, rheological property and water absorption of PBS/lignin were investigated. The results showed that the use of MAH grafted polymers and silanes resulted in significant improvements in flexural property, tensile modulus and tensile strength. Furthermore, MAH grafted polymers and silanes exhibited some improvement on the properties of vicat softening temperature as well as water absorption. The composites treated by MAH grafted polymers and silanes showed non-Newtonian behaviors from rheological tests. A better interfacial adhesion between lignin and matrix was observed from the scanning electron microscopy (SEM) of the compatibilized composites.