Entity

Time filter

Source Type

Montreal, Canada

Nguyen T.-D.,University of British Columbia | Hamad W.Y.,CelluForce Inc. | Maclachlan M.J.,University of British Columbia
Advanced Functional Materials | Year: 2014

Simultaneous integration of light emission and iridescence into a semiconducting photonic material is attractive for the design of new optical devices. Here, a straightforward, one-pot approach for liquid crystal self-assembly of semiconductor quantum dots into cellulose nanocrystal-templated silica is developed. Through a careful balance of the intermolecular interactions between a lyotropic tetraalkoxysilane/cellulose nanocrystal dispersion and water-soluble polyacrylic acid/mercaptopropionic acid-stabilized CdS quantum dots, CdS/silica/nanocellulose composites that retain both chiral nematic order of the cellulose nanocrystals and emission of the quantum dots are successfully co-assembled. Subsequent removal of the cellulose template and organic stabilizers in the composites by controlled calcination generates new freestanding iridescent, luminescent chiral nematic mesoporous silica-encapsulated CdS films. The pores of these materials are accessible to analytes and, consequently, the CdS quantum dots undergo strong luminescence quenching when exposed to TNT solutions or vapor. Liquid crystal-templated self-assembly of water-soluble, stabilized CdS quantum dots into a lyotropic alkoxysilane/cellulose nanocrystal dispersion produced chiral nematic CdS/silica/cellulose composites. Subsequent removal of the cellulose template and other additives by controlled calcination generated freestanding iridescent, luminescent chiral nematic mesoporous silica-encapsulated CdS films. This one-pot alternative route to fabricate these new semiconducting photonic materials may prove useful in the design of sensors and optical devices. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source


Kelly J.A.,University of British Columbia | Shukaliak A.M.,University of British Columbia | Cheung C.C.Y.,University of British Columbia | Shopsowitz K.E.,University of British Columbia | And 2 more authors.
Angewandte Chemie - International Edition | Year: 2013

All in order: The self-assembly of nanocrystalline cellulose (NCC) with hydrogel precursors leads to nanocomposites with long-range chiral nematic order. The combination of chiral structure and hydrogel swelling behavior gives rise to iridescence that rapidly responds to various stimuli. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source


Chen L.,University of Waterloo | Berry R.M.,CelluForce Inc. | Tam K.C.,University of Waterloo
ACS Sustainable Chemistry and Engineering | Year: 2014

This paper reports on the synthesis of β-cyclodextrin-modified CNC@Fe3O4@SiO2 superparamagnetic nanorods for the removal of two model compounds: procaine hydrochloride and imipramine hydrochloride. During the synthetic process, sustainable natural materials and low-cost chemicals were used, and mild reaction conditions were adopted. TEM and SEM images indicated good dispersion of Fe3O4 nanoparticles with uniform silica coating on CNCs. The thickness of the silica coating was controlled by manipulating the amounts of precursor solution used. TGA data confirmed that the silica coating significantly enhanced the thermal stability of CNCs. The onset decomposition temperature of CNC@Fe 3O4@SiO2 hybrids increased by 60 °C compared to pure CNCs. XRD, EDS, and FT-IR analyses confirmed the structure of CNC@Fe3O4@SiO2 and the successful grafting of β-cyclodextrin. The CNC@Fe3O4@SiO2β- CD hybrids displayed good adsorption toward the model pharmaceutical residues: procaine hydrochloride and imipramine hydrochloride. © 2014 American Chemical Society. Source


Patent
CelluForce Inc. | Date: 2013-07-17

The present disclosure relates to surface modified nanocrystalline cellulose (NCC) prepared by chemical modification of NCC as well as its use thereof, including as carrier of particular chemical compounds. The surface of nanocrystalline cellulose (NCC) was modified with chitosan oligosaccharide (CS


Nanocrystalline cellulose (NCC)-based supramolecular materials, a method for their preparation and their use in thermoplastic and thermoset polymer composites are disclosed. Supramolecular materials of NCC and one or two polymers are synthesized by in situ surface graft copohmerization in a multitude of solvent systems, including water. The nano-scale size supramolecular materials are engineered to have a unique combination of lowr polarity and high hydrophobicity and function as copohmers for demanding pohmeric systems such as, but not limited to, polyolefins and polyesters. Nanocomposite materials of enhanced functionality and mechanical properties are produced by compounding the NCC-based supramolecular materials with polymer matrices. The supramolecular materials are used in composite development for packaging materials, structural composites for automotive and construction, as sandwiched foam composites or, combined with biocompatible polymers, in medical applications.

Discover hidden collaborations