TY  - JOUR
A1  - Tritschler, Ulrich
A1  - Zlotnikov, Igor
A1  - Fratzl, Peter
A1  - Schlaad, Helmut
A1  - Gruener, Simon
A1  - Coelfen, Helmut
T1  - Gas barrier properties of bio-inspired Laponite-LC polymer hybrid films
JF  - PLoS one
N2  - Bio-inspired Laponite (clay)-liquid crystal (LC) polymer composite materials with high clay fractions (>80%) and a high level of orientation of the clay platelets, i.e. with structural features similar to the ones found in natural nacre, have been shown to exhibit a promising behavior in the context of reduced oxygen transmission. Key characteristics of these bio-inspired composite materials are their high inorganic content, high level of exfoliation and orientation of the clay platelets, and the use of a LC polymer forming the organic matrix in between the Laponite particles. Each single feature may be beneficial to increase the materials gas barrier property rendering this composite a promising system with advantageous barrier capacities. In this detailed study, Laponite/LC polymer composite coatings with different clay loadings were investigated regarding their oxygen transmission rate. The obtained gas barrier performance was linked to the quality, respective Laponite content and the underlying composite micro-and nanostructure of the coatings. Most efficient oxygen barrier properties were observed for composite coatings with 83% Laponite loading that exhibit a structure similar to sheet-like nacre. Further on, advantageous mechanical properties of these Laponite/LC polymer composites reported previously give rise to a multifunctional composite system.
KW  - gas permeation
KW  - liquid crystal
KW  - Laponite
KW  - liquid crystal polymer
KW  - bio-inspired
KW  - organic-inorganic composite material
KW  - self-organization
Y1  - 2016
U6  - https://doi.org/10.1088/1748-3190/11/3/035005
SN  - 1748-3182
SN  - 1748-3190
VL  - 11
PB  - IOP Publ. Ltd.
CY  - Bristol
ER  - 
TY  - JOUR
A1  - Tritschler, Ulrich
A1  - Zlotnikov, Igor
A1  - Keckeis, Philipp
A1  - Schlaad, Helmut
A1  - Cölfen, Helmut
T1  - Optical properties of self-organized gold nanorod-polymer hybrid films
JF  - Langmuir
N2  - High fractions of gold nanorods were locally aligned by means of a polymeric liquid crystalline phase. The gold nanorods constituting >80 wt % of the thin organic-inorganic composite films form a network with side-by-side and end-to-end combinations. Organization into these network structures was induced by shearing gold nanorod-LC polymer dispersions via spin-coating. The LC polymer is a polyoxazoline functionalized with pendent cholesteryl and carboxyl side groups enabling the polymer to bind to the CTAB stabilizer layer of the gold nanorods via electrostatic interactions, thus forming the glue between organic and inorganic components, and to form a chiral nematic lyotropic phase. The self-assembled locally oriented gold nanorod structuring enables control over collective optical properties due to plasmon resonance coupling, reminiscent of enhanced optical properties of natural biomaterials.
Y1  - 2014
U6  - https://doi.org/10.1021/la503507u
SN  - 0743-7463
VL  - 30
IS  - 46
SP  - 13781
EP  - 13790
PB  - American Chemical Society
CY  - Washington
ER  -