Nanocomposites Assembled via Electrostatic Interactions between Cellulose Nanocrystals and a Cationic Polymer.

On account of their high strength and stiffness and their renewable nature, cellulose nanocrystals (CNCs) are widely used as a reinforcing component in polymer nanocomposites. However, CNCs are prone to aggregation and this limits the attainable reinforcement. Here, we show that nanocomposites with a very high CNC content can be prepared by combining the cationic polymer poly[(2-(methacryloyloxy)ethyl) trimethylammonium chloride] (PMETAC) and negatively charged, carboxylated CNCs that are provided as a sodium salt (CNC-COONa).

Squid Beak Inspired Cross-Linked Cellulose Nanocrystal Composites.

Bioinspired cross-linked polymer nanocomposites that mimic the water-enhanced mechanical gradient properties of the squid beak have been prepared by embedding either carboxylic acid- or allyl-functionalized cellulose nanocrystals (CNC) into an alkene-containing polymer matrix (poly(vinyl acetate--vinyl pentenoate), P(VAc--VP)). Cross-linking is achieved by imbibing the composite with a tetrathiol cross-linker and carrying out a photoinduced thiol-ene reaction. Central to this study was an investigation on how the placement of cross-links (i.

Implications of the Differential Toxicological Effects of III-V Ionic and Particulate Materials for Hazard Assessment of Semiconductor Slurries.

Because of tunable band gaps, high carrier mobility, and low-energy consumption rates, III-V materials are attractive for use in semiconductor wafers. However, these wafers require chemical mechanical planarization (CMP) for polishing, which leads to the generation of large quantities of hazardous waste including particulate and ionic III-V debris. Although the toxic effects of micron-sized III-V materials have been studied in vivo, no comprehensive assessment has been undertaken to elucidate the hazardous effects of submicron particulates and released III-V ionic components.