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Alkyl ketene dimers (AKDs) are known to efficiently react with cellulose with a dual polarity in their structure: a polar component and a nonpolar component. AKD of three different carbon chain lengths, 4, 10, and 16 carbons have been synthesized, and thermomechanical pulp (TMP) fibers were modified by them. The modification of TMP fibers with AKD resulted in an increased water contact angle, showing the presence of the AKDs on the TMP fibers and a new carbonyl peak in the IR spectra, suggesting modification of the TMP fibers with AKD groups. Calculating the Hansen solubility parameters of AKD and AKD conjugated to TMP in polypropylene (PP) indicates improved compatibility, especially of longer chain AKD and TMP AKD. The rheological studies of the composites showed that the AKD with the longest carbon chain decreases the melt viscosity of the PP‐TMP‐AKD composite, which combined with the shape and the color of the extruded composite filaments indicates improved flow properties and reduced stress build up during processing. The research findings demonstrate the ability of AKD to enhance the dispersibility and compatibility of natural fibers with PP. [ABSTRACT FROM AUTHOR]

The study presents a more efficient way of exfoliating MoS2 in water and the exfoliated MoS2 was used in an electrode. The electrodes were prepared from exfoliated MoS2 (active material)–nanocrystalline cellulose (binder) with carbon nanotubes (electron-conducting support) and demonstrated in a zinc battery half-cell that showed a Coulombic efficiency of 90%. Successful exfoliation of MoS2 was done by sonication of bulk MoS2 with sulfated cellulose nanocrystals (CNC) for 4 h. The exfoliation was confirmed by Raman and transmission electron microscopy; interestingly, the Raman signals for exfoliated MoS2 show a blue shift for both A1g and E2g1 bands, which may be an indication of an induced lattice strain effect from the CNC on MoS2. The resulting stable water suspension showed no tendency of precipitation after 2 months of standing. The zeta potential, ζ, for sodium sulfated CNC (CNC–OSO3Na)–MoS2 in water suspension was −45 mV, whereas sulfated CNC (CNC–OSO3H)–MoS2 in water suspension had a zeta potential of −35 mV. The sodium form of sulfated CNCs displayed micelle characteristics, similar to sodium dodecyl sulfate (SDS), with a critical aggregation concentration (CAC) of 1.1 wt %. At CAC, the CNCs efficiently exfoliated MoS2, which is at a much lower concentration than has been reported for synthetic surfactants like SDS and cetyl trimethyl ammonium bromide. [ABSTRACT FROM AUTHOR]