Nanostrukturierte Materialien  
Nanocomposites & Nanoparticles
Nanostructured Thin Films & Coatings
Micro- & Nanofabrication
Micro- & Nanocharacterization

Nanocomposite Materials and Nanoparticles

Nanoparticles play a key role in advanced catalysts, ceramics, electronic devices as well as polymer composites and coatings, due to their different physical and chemical properties compared to conventional material. EMPA has the established know-how and facilities for nanoparticle synthesis in lab and pilot-scale powder batches. Flame spray synthesis (FSS) allow synthesis of oxide nanoparticles such as silica, titania, zirconia, perovskites, various types of mixed oxides and composite particles with well defined composition, morphology and surface. Tailored oxide nanoparticles in polymer composites and coatings are known to lead to improved mechanical properties, super-hydrophilicity, easy-to-clean and anti-bacterial properties. In high energy ball milling nanopowders are manufactured from bulk material of tailored composition, such as glass with several constituents, bio or medical filler materials. Non-oxide nanoparticles like carbides, nitrides and pure metals are produced preferentially out of solid precursors using the inductively coupled vacuum plasma process (ICP).

Empa’s pilot plant enables the production of nano-powders in relevant quantities. The carbides and nitrides can be used in metallurgical applications for dispersion hardening, improving so hardness, wear resistance and toughness. Due to their enhanced activity, metallic nanoparticles like silicon or titanium are interesting candidates in catalysis or in pyrotechnical applications.

The functional and structural performance of metallic and ceramic materials, including e.g. thermal and electrical conductivity, CTE, hardness, wear resistance, elevated temperature stability, can be considerably enhanced by the integration of ultrafine nano-sized structures. The properties of nanocomposites are determined not only by the morphology and spatial distribution of the nanophase, but also depend on mutual chemical and physical interactions between the different phases involved. The successful development of nanocomposites requires advanced process technologies such as liquid phase infiltration of nano-structured preforms, in-situ reactive synthesis, electroless deposition techniques and powder metallurgy.

At Empa, these technologies are continuously pushed to develop and fabricate novel materials and prototypes such as: High temperature sensors (doped Si3N4), heat resistant pistons (dispersion strengthened Al), thermal management materials (tailored metallic/ceramic composites), brazing materials (with active fillers), solide oxide fuel cell (SOFC) electrodes (nano-porous composites) and wear protective layers.

Nanoparticles embedded in a polymer matrix or coating provide added values like scratch resistance, easy-to-clean  properties or tailor made optical properties. In contrast to microparticles, homogeneously and completely dispersed nanoparticles will improve the mechanical properties of their polymer host matrix (even in a fibre reinforced polymer composite component).

Fracture surface of a GFRP specimen after a quasi-static delamination resistance (DCB) test with a modified epoxy matrix with 10 weight percent organo-nanoclay analysed by ESEM.

Very interesting perspectives lie furthermore in electric, electrochemical as well as optical properties. The understanding of local particle interactions and its influence on processing and stability of nanocomposites is fundamental for large-scale applications of organic-inorganic hybrid materials and is therefore studied thoroughly.
Contact
Access to the world of Empa online
zurück  Links  Druckansicht