Effects of different interfacial modifiers on the properties of digital printing waste paper fiber/nanocrystalline cellulose/poly(lactic acid) composites

Digital printing waste paper fiber/nanocrystalline cellulose/poly(lactic acid) composites, modified through γ-methacryloxy propyl trimethoxy silane (KH570), isopropyl tri(dioctylpyrophosphate) titanate, sodium hydroxide, polyethylene glycol 6000 (PEG6000), and a composite coupling agent (KH570/PEG6000), were fabricated by melt blending injection molding, the effects of different modifiers on properties composites studied. The results show that mechanical improved, best flexural strength, tensile impact strength obtained PEG6000, KH570/PEG6000, KH570, respectively. Thermogravimetric analysis showed thermal decomposition performance treated KH570 was relatively superior. Differential scanning calorimetry demonstrated melting enthalpy crystallinity material increased, while cold crystallization temperature decreased. After modification, both water absorption degradation decreasing trend, especially KH570/PEG6000. Under action several modifiers, diffusion coefficient, thermodynamic solubility, permeability reduced to varying degrees. Furthermore, electron microscopy interfacial adhesion compatibility improved with significantly fewer smaller pores, as well fuzzy boundary among three phases.