No abstract

Cellulose nanocrystals (CNCs) are renewable, nontoxic and naturally available organic nano particles derived from cellulosic resources such as cotton and wood pulp. Poly(n-butyl acrylate-co-methyl methacrylate)/CNC latexes are successfully synthesized via in situ emulsion polymerization. The effect of CNC loading on overall conversion, polymer particle size, glass transition temperature (T g ), gel content, latex viscosity, and storage and loss moduli of dried latex are studied. While the effect of CNC content on overall conversion, polymer particle size, and T g of the resulting latexes is negligible, significant increase in gel content, latex viscosity, and storage and loss moduli are observed.

Front Cover: Cellulose nanocrystals (CNCs) are combined with a butyl acrylate/methyl methacrylate emulsion polymerization formulation in situ to form nanocomposite adhesives. The addition of CNCs provides a means to simultaneously increase tack, peel strength and shear strength. Further details can be found in the article by Zahra Dastjerdi, Emily D. Cranston and Marc A. Dubé, article number https://doi.org/10.1002/mren.201700013.

Emulsion‐based coatings and adhesives are in growing demand due to an increased awareness of health and safety issues arising from solvent‐based polymer manufacturing processes. However, emulsion‐based techniques often require additional development to achieve equal or better application performance compared to solvent‐based processes. The inclusion of nanoparticles in emulsion‐based coatings and adhesives can be considered as a promising means to enhance performance. This paper reviews the current progress on the synthesis of emulsion‐based nanocomposites for coating and adhesive applications and addresses the principles and techniques for nanoparticle dispersions and their inclusion into polymer latexes. The effects of nanoparticle shape and size on the enhancement of nanocomposite properties are also highlighted. Among the reinforcing nanoparticles such as nanoclays, carbon nanotubes, and cellulose nanocrystals (CNCs), CNCs are promising due to their abundance, nontoxicity, and accessible surface hydroxyl groups, which facilitate their compatibility with polymer latexes via physical and chemical treatments.

The reclamation of mining operation tailings water is of major concern to the oil sands industry. Naphthenic acids (NAs) are recognized as a major toxic component in tailings water. The acid‐catalyzed esterification of commercially prepared NAs to biodiesel was performed as a test case for the utilization of these toxic compounds. In a series of batch acid‐catalyzed esterification reactions, the influence of reaction temperature, catalyst type, catalyst concentration, and methanol to oil ratio on the esterification was investigated. The NA esterification reactions were found to be positively dependent on temperature and catalyst concentration while large methanol to oil ratios had a negative effect on the esterification. Finally, sulfuric acid was identified as a preferred catalyst for the esterification compared to p‐toluene sulfonic acid. The esterification was completed successfully at the relatively mild conditions used in commercial biodiesel production. © 2012 American Institute of Chemical Engineers Environ Prog, 32: 406‐410, 2013