Likozar B.,Polymer Competence Center Leoben |
Likozar B.,University of Ljubljana
Soft Matter | Year: 2011
In order to achieve good morphological, mechanical, structural, and thermal properties of a polymer electrolyte, ionic-liquid-in-polymer electrolytes have been explored. It was found that 1-ethyl-3-methylimidazolium, 1-butyl-3-methylimidazolium, and 1-butyl-1-methylpyrrolidinium tetrafluoroborate (EMImBF 4, BMImBF 4, and BMPyBF 4), hexafluorophosphate (EMImPF 6, BMImPF 6, and BMPyPF 6), and bis(trifluoromethylsulfonyl)imide (EMImTFSI, BMImTFSI, and BMPyTFSI) in hydroxy-functionalized multi-walled carbon nanotubes (MWCNT-OH) reinforced hydrogenated poly(acrylonitrile-co-1,3-butadiene) (HNBR) produce homogeneous solids. HNBR/MWCNT-OH/ionic liquid solid electrolytes were prepared by melt compounding of the nanotubes in the elastomer, mixing with curing system, curing, and immersion in the ionic liquid. Cross-linked with 12.9 wt% of the curing system (per total composite weight prior to ionic liquid sorption), these HNBR-based electrolytes displayed elastomeric properties and high tensile strength (up to 24 MPa). HNBR/MWCNT-OH/ionic liquid composites had the elongation at break up to 378% (BMPyTFSI) at the room temperature and ionic liquid concentrations up to 18 wt% (BMImTFSI). Thermal analysis showed that the T g of HNBR/MWCNT-OH/ionic liquid systems decreased as a function of increasing ionic liquid content at the constant polymer content in a composite. © 2011 The Royal Society of Chemistry.
Agency: European Commission | Branch: H2020 | Program: MSCA-ITN-ETN | Phase: MSCA-ITN-2016 | Award Amount: 3.58M | Year: 2016
The quality assurance in the photovoltaic industry is yet in its infancy, requiring both underpinning science and trained personnel to reduce costs of energy. An unmet industrial requirement is an accelerated, and operating environment specific, service life time and energy yield assessment. SOLAR-TRAIN will qualify ESRs in the field of PV durability as part of a highly innovative, multi-disciplinary project meeting industry requirements. The objective is to develop novel, validated models for the service life time and energy prediction of PV modules and systems. The elements to this puzzle are researched in the frame of 14 PhD projects with individual areas of focus, such as (a) climatic degradation factors, (b) system analytics, (c) material (polymer) parameters, (d) service life & energy models, (e) linking production to performance and (f) performance enhancement by improved O&M. Commercial and test samples will be produced and tested in the distributed measurement campaign during this project. They will be exposed to state-of-the-art and to-be-developed stress cycles to allow a validated link of degradation to stresses, production methods, materials and methods of deployment. Accelerated and lower cost test cycles for the assessment of innovative materials and module developments will be delivered. The project is integrated both in terms of research as well as training. This inter-sectoral approach provides excellent theoretical and technical background as well as immersion in different business sectors and career mentoring, allowing ESRs to build up a sustainable professional network across Europe. For a most effective cross-sectoral training, the projects beneficiaries and partners represent the entire value chain, from materials developers / manufacturers through to operators and insurance companies. SOLAR-TRAIN will deliver on the targets stated in Issue Paper No. 2 of the SET Plan to maintain and strengthen PV leadership in Europe.
Kelly A.M.,Polymer Competence Center Leoben |
Wiesbrock F.,University of Graz
Macromolecular Rapid Communications | Year: 2012
Poly(2-oxazoline)-based networks currently receive great interest due to their versatile properties that can be tailor made by desktop-planned modifications. This feature summarizes strategies for the preparation of these networks, comprising the in situ cross-linking as well as polymer-analogous cross-linking routines such as (reversible) complex formation, physical processes, and covalent bond formation (involving reactions with olefinic species as well as with epoxides, isocyanates, aldehydes, acids, and their derivatives). Reflecting prominent application examples in the biomedic(in)al sector, poly(2-oxazoline)-co-polyester networks are described in a dedicated section. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Frank A.,Polymer Competence Center Leoben |
Pinter G.,University of Leoben
Polymer Testing | Year: 2014
Several tests methods are available for the characterization of the slow crack growth (SCG) resistance of polyethylene (PE) for pipe applications. Unfortunately, due to the increase of the SCG resistance of modern PE pipe grades, these test methods are exceeding practical time frames so that new test methods for accelerated and reliable material ranking are required. The Cyclic CRB Test was proposed as a promising test method for a quick material ranking of PE pipe grades by their SCG resistance, even at ambient temperatures. In this, paper different studies about the Cyclic CRB Test are summarized. On the one hand, the results show the potential for a quick and reliable material ranking at ambient temperatures within only a couple of days, even for modern PE 100-RC grades. On the other hand, results of two Round Robin Tests will be discussed. The presented results demonstrate high reproducibility and reliability of the Cyclic CRB Test in terms of material ranking by SCG resistance. © 2013 Elsevier Ltd. All rights reserved.
Koller M.,University of Graz |
Muhr A.,University of Graz |
Muhr A.,Polymer Competence Center Leoben |
Braunegg G.,ARENA Arbeitsgemeinschaft fur Ressourcenschonende und Nachhaltige Technologien
Algal Research | Year: 2014
As major part of the phytoplankton, microalgae are pivotal for the global food chain. Their exceptional capacity for CO2-fixation illustrates their indispensable significance to sustain earth's ecosystems. Further, they play a still underestimated role in eliminating contaminants from various environments. In addition to ecological benefit, many microalgal species exhibit high nutritional value and, at the same time, generate valued bio-products: Pigments, lipids, bioactive compounds, certain polysaccharides, bio-hydrogen and even biopolyesters with plastic-like properties have the potential for successful market penetration.Three substantial pigment groups, namely chlorophylls, carotenoids, and phycobilins, are essential for light harvesting and CO2 fixation. Those pigments will most likely undergo quick commercial success in "functional food", cosmetics, aquaculture, pharmaceuticals, or food technology.Due to often high contents of polyunsaturated fatty acids essential for human metabolism, microalgal oils can be commercialized as health food and in the pharmaceutical and therapeutic field, creating much higher value than by converting them to biofuel.Finally, algal biomass remaining as residue after product recovery can be used as forage, biogas feedstock or biofertilizer. This utilization is needed for balancing the material- and energy cycles of the entire process. Thus, technology platforms following the principles of bio-refineries shall be established to enable the design of sustainable and economically feasible production of marketable microalgal products. © 2014 Elsevier B.V.
Weber A.,Polymer Competence Center Leoben |
Resch K.,University of Leoben
Energy Procedia | Year: 2012
In this paper, the effect of material composition on the overheating protection performance of thermotropic systems with fixed domains (TSFD) is studied. Several thermotropic layers were formulated by variation of both, matrix material and thermotropic additive. Refractometry was applied in order to obtain refractive index data as a function of temperature of all material constituents and to screen wether material combinations are promising to formulate or not. Investigations concerning optical properties, switching temperature and switching process were carried out applying UV/Vis/NIR spectrometry. Morphological analysis was conducted with a Scanning Electron Microscope (SEM). Several TSFD showed reasonable light-shielding efficiency. Nevertheless further optimization of scattering domain size and shape is necessary to improve the light shielding performance. © 2012 The Authors.
Weber A.,Polymer Competence Center Leoben |
Resch K.,University of Leoben
Journal of Applied Polymer Science | Year: 2014
This article presents a systematic strategy for formulation and optimization of thermotropic layers for overheating protection purposes. Specifically, thermotropic systems with fixed domains (TSFD) which consist of a thermotropic additive finely dispersed in a matrix material are considered. Based on systematic material (component) preselection regarding thermoanalytical characteristics and refractive indices, numerous thermotropic layers were formulated. TSFD with thermoplastic matrix were produced by compounding and compression molding. TSFD with resin matrix were produced by UV curing. The thermotropic layers were analyzed as to solar optical properties, threshold temperature, switching process and residual transmittance in the opaque state applying UV/Vis/NIR spectrometry equipped with a heating stage. Best performing materials exhibited solar hemispheric transmittance in the range of 72.2-84.5% and between 59.6 and 83.7% in the clear and opaque state, respectively. Threshold temperatures between 45 and 75°C were realized. Refractive index difference between matrix and additive and solar hemispheric transmittance displayed a close correlation. Hence, refractometry was shown to be an appropriate tool for material preselection. Furthermore, investigations revealed a close correlation of thermal transitions of thermotropic additives recorded by differential scanning calorimetry and threshold temperatures of thermotropic layers formulated therewith. However, thermotropic layers formulated so far have to be optimized with respect to light-shielding performance for efficient overheating protection. © 2013 Wiley Periodicals, Inc.
Agency: European Commission | Branch: FP7 | Program: JTI-CS | Phase: JTI-CS-2012-1-GRC-06-006 | Award Amount: 199.97K | Year: 2012
With the future use of thermoplastic composite (TPC) helicopter parts, recycling, repairing and reuse of used composite parts become within reach. In order to recycle used parts of an assembly group the joints have to be detachable. Disacop will investigate a thermoplastic separation scenario that will allow disassembling the parts of a structure by fusion debonding for recycling. Due to the thermoplastic behavior of the TPC components, the fusion zone can be weakened by temperature. To ensure component separation at the joining interface between the components a special separation layer will be investigated if necessary. The separation is intended to be without degradation of the TPC parts. For economic and environmental reasons the heating will be limited to local heating of the joining zone. The possible joining and separation layer is intended to be used as a heating element as well. Based on the available demonstrators, Disacop will identify a method to locally apply heat and to debond the assemblies. An energy-efficient technology is induction heating. The approach is to perform first trials on available coupons and subcomponents from the industrial partners to understand the process effects on real joints. Then the technology will be fine-tuned based on the requirements coming from the industrial partners, first on coupon level. Subsequently, the technology will be scaled up to subcomponents/ validation articles and the demonstrators. To prove the environmental benefits of the Disacop separation method data for life cycle assessment will be collected, for economic assessment a cost analysis for evaluation has to be made.
Electrode For An Electrochemical Element With An Organic Electrolyte, Electrochemical Elements Comprising The Electrode And Polymeric Material And Its Use As Electrode Active Material Or As Electrode Binder
VARTA Micro Innovation GmbH and Polymer Competence Center Leoben | Date: 2016-06-15
Disclosed is an electrode comprising a polymeric material containing or being composed of subunits according to general formulae (I) and (II)_(1), R_(2), R_(3) and R_(4) each independently represent H, alkyl (preferably-CH_(3), -C_(2)H_(5)), alkoxy-(preferably -OCH_(3), -OC_(2)H_(5)), -halogen or -CN, Ar_(1) and Ar_(4) independently represent a bridging aryl group, Ar_(2) and Ar_(3) independently represent a non-bridging aryl group, and R_(5) is a bridging alkyl or aryl group. Further, a Lithium-ion battery and a supercapacitor with such an electrode and the use of said polymeric material as electrode active material in the electrode of a battery or in the electrode of a supercapacitor and/or as an electrode binder is disclosed.
Morphology, mechanical, cross-linking, thermal, and tribological properties of nitrile and hydrogenated nitrile rubber/multi-walled carbon nanotubes composites prepared by melt compounding: The effect of acrylonitrile content and hydrogenation
Likozar B.,Polymer Competence Center Leoben |
Major Z.,Polymer Competence Center Leoben
Applied Surface Science | Year: 2010
The purpose of this work was to prepare nanocomposites by mixing multi-walled carbon nanotubes (MWCNT) with nitrile and hydrogenated nitrile elastomers (NBR and HNBR). Utilization of transmission electronic microscopy (TEM), scanning electron microscopy (SEM), and small- and wide-angle X-ray scattering techniques (SAXS and WAXS) for advanced morphology observation of conducting filler-reinforced nitrile and hydrogenated nitrile rubber composites is reported. Principal results were increases in hardness (maximally 97 Shore, type A), elastic modulus (maximally 981 MPa), tensile strength (maximally 27.7 MPa), elongation at break (maximally 216%), cross-link density (maximally 7.94 × 1028 m-3), density (maximally 1.16 g cm -3), and tear strength (11.2 kN m-1), which were clearly visible at particular acrylonitrile contents both for unhydrogenated and hydrogenated polymers due to enhanced distribution of carbon nanotubes (CNT) and their aggregated particles in the applied rubber matrix. Conclusion was that multi-walled carbon nanotubes improved the performance of nitrile and hydrogenated nitrile rubber nanocomposites prepared by melt compounding. © 2010 Elsevier B.V.