Photonic metal–polymer resin nanocomposites with chiral nematic order

2016 ◽  
Vol 52 (50) ◽  
pp. 7810-7813 ◽  
Author(s):  
Vitor M. Zamarion ◽  
Mostofa K. Khan ◽  
Maik Schlesinger ◽  
Anas Bsoul ◽  
Konrad Walus ◽  
...  

Metal nanoparticles that spontaneously nucleate in the chiral channels of a polymer resin templated by cellulose nanocrystals form ink-jet printed images.

2021 ◽  
Author(s):  
Arash Momeni ◽  
Christopher M. Walters ◽  
Yi-Tao Xu ◽  
Wadood Y. Hamad ◽  
Mark J. MacLachlan

A cellulose nanocrystal liquid crystalline suspension was mixed with monomers and confined to a capillary tube. After photopolymerization, a fiber with a single-domain concentric chiral nematic structure throughout the length of the fiber was obtained.


2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Dawei Zhang ◽  
Lihong Zhang ◽  
Bingzhe Wang ◽  
Guangzhe Piao

Stable lyotropic chiral nematic liquid crystals (N*-LCs) of cellulose nanocrystals (CNs) were prepared via hydrolysis using sulfuric acid. The lyotropic N*-LCs were used as an asymmetric reaction field to synthesize polyaniline (PANI) onto CNs by in situ polymerization. As a primary step, we examined the mesophase transition of the N*-LCs of CNs suspension before and after in situ polymerization of aniline (ANI) by polarizing optical microscopy. The structure of nanocomposites of PANI/CNs was investigated at a microscopic level using Fourier transform infrared spectroscopy and X-ray diffraction. Influence of the CNs-to-ANI ratio on the morphology of the nanocomposites was also investigated at macroscopic level by scanning electron and transmission electron microscopies. It is found that the weight ratio of CNs to aniline in the suspension significantly influenced the size of the PANI particles and interaction between CNs and PANI. Moreover, electrical properties of the obtained PANI/CNs films were studied using standard four-probe technique. It is expected that the lyotropic N*-LCs of CNs might be available for an asymmetric reaction field to produce novel composites of conjugated materials.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
C.F. Castro-Guerrero ◽  
A.B. Morales-Cepeda ◽  
M.R. Díaz-Guillén ◽  
F. Delgado-Arroyo ◽  
F.A. López-González

Abstract Cellulose nanocrystals were extracted from cotton. The cellulose nanocrystals made a self-assembly structure when dried under slow conditions, as it was revealed by the characterization made to the material. The AFM images of the nanocrystals showed that they had a changing local orientation, pointing in a preferred direction that underwent a periodic change. This periodic change resembles the orientation of a chiral nematic phase. The TEM images showed that the nanocrystals had a rod-like appearance with average length size of 98.5 nm and a diameter of 4.7 nm. The TEM characterization showed the nanocrystals with more details than AFM. In this paper, the self-assembling of CNC was observed by AFM, and further investigations were done by TEM, deconvoluting the process of CNC nanorods aggregation.


ACS Nano ◽  
2015 ◽  
Vol 9 (10) ◽  
pp. 10377-10385 ◽  
Author(s):  
Ana Querejeta-Fernández ◽  
Bernd Kopera ◽  
Karen S. Prado ◽  
Anna Klinkova ◽  
Myriam Methot ◽  
...  

Cellulose ◽  
2019 ◽  
Vol 27 (4) ◽  
pp. 2003-2014 ◽  
Author(s):  
Roland Kádár ◽  
Mina Fazilati ◽  
Tiina Nypelö

Abstract Organization of nanoparticles is essential in order to control their light-matter interactions. We present cellulose nanocrystal suspension organization in flow towards a unidirectional state. Visualization of evolving polarization patterns of the cellulose nanocrystal suspensions is combined with steady and oscillatory shear rheology. Elucidation of the chiral nematic mesophase in a continuous process towards unidirectional order enables control of alignment in a suspension precursor for structural films and reveals thus far in situ unrevealed transition states that were not detectable by rheology alone. The coupled analytics enabled the suspensions of interest to be divided into rheological gels and rheological liquid crystal fluids with detailed information on the microtransition phases. Both populations experienced submicron organization and reached macro-scale homogeneity with unidirectional ordering in continued shear. We quantify the time, shear rate, and recovery time after shear to design an optimizing formation process for controlled wet structures as precursors for dry products. Graphic abstract


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