Bio-sourced vinyl ester resin reinforced with microfibrillar cellulose: Mechanical and thermal properties

New thermoset composite material made from cardanol-based resin blended with microfibrillar cellulose was compared to petroleum-based vinyl ester and glass-fiber-reinforced unsaturated polyester in terms of mechanical, thermal, rheological and surface properties of produced polymers and composites. The bio-sourced material was less resistant than the commercial vinyl ester but comparable to the unsaturated polyester resin. Microfibrillar cellulose increased the tensile strength and modulus but increased the resin viscosity and decreased the mixture homogeneity. The bio-sourced and commercial resins displayed similar hydrophobic behavior, and cellulose slightly decreased composite hydrophobicity. The glass transition temperature of the bio-sourced material was comparable to that of the unsaturated polyester. Thermal decompositions of composites and thermoset polymers were also similar. Cellulose and cardanol thus may be adequate as sustainable components in the composite materials industry.

Extraction of Microfibrillar Cellulose From Waste Paper by NaOH/Urethane Aqueous System and Its Utility in Removal of Lead from Contaminated Water

Though recycling of waste paper is widely practiced but usually it is downgraded to lower valued recycled waste paper. Based on this concern, we report the development of novel NaOH/urethane aqueous system for extraction of microfibrillated cellulose from waste paper. The purity of so obtained microfibrillated cellulose (MFC) was evaluated by morphological tests using scanning electron microscopy (SEM) and transmission electron microscopy (TEM) and by evaluation of physicochemical properties using Fourier-transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). Morphologies of MFC studied by SEM and TEM showed that the size of purified cellulose fibrils reduced when compared to that of waste paper but fibrils are cleaner and smoother due to the removal of talc and lignin. XRD analysis revealed that MFC exhibits good crystallinity. The utility of sulfonated and pristine microfibrillar cellulose in removal of lead from contaminated water is also reported. Our results show that renewable, sustainable, cheap, and waste biomass like waste paper can be used for producing valuable second-generation high-value products.

Loading of Iron (II, III) Oxide Nanoparticles in Cryogels Based on Microfibrillar Cellulose for Heavy Metal Ion Separation

Cryogels based on microfibrillar cellulose (MFC) and reinforced with chitosan to endow water resistance were loaded with magnetite nanoparticles (MNPs) and characterized by TEM, XRD, and TGA. The MNP-loaded cryogels were tested for heavy metal ion removal from aqueous matrices. The adsorption capacity under equilibrium conditions for Cr(VI), Pd(II), Cd(II), and Zn(II) was measured to be 2755, 2155, 3015, and 4100 mg/g, respectively. The results indicate the potential of the introduced bicomponent cryogels for nanoparticle loading, leading to a remarkably high metal ion sorption capacity.