Advanced polyoxymethylene-based nanostructured materials
|Krzysztof Pielichowski , Agnieszka Leszczynska|
Cracow University of Technology, Department of Chemistry and Technology of Polymers, ul. Warszawska 24, Kraków 31-155, Poland
Polymeric nanostructured materials differ from conventional composites in that the mixing of phases occurs over a much smaller length scale in comparison to the micrometer length scale of conventional composites, resulting in to nanocomposite materials with properties substantially different from those of the parent end members. The properties of the matrix, the distribution and properties of the filler as well as the nature of their interface control the behaviour of a typical composite material. Thus, the nanoparticles often strongly influence the properties of the composites at very low volume fractions. This is mainly due to their small interparticle distances and the conversion of a large fraction of the polymer matrix near their surfaces into an interphase of different properties as well as to the consequent change in morphology. As a result, the desired properties are usually reached at low filler volume fraction, which allows the nanocomposites to retain the macroscopic homogeneity and low density of the polymer. One of the most important engineering polymers with a unique set of mechanical, thermal, chemical and electrical properties is polyoxymethylene (POM). Among various POM systems with high impact resistance, blends of POM and (nano)segmented thermoplastic polyurethanes (TPUs) are considered as very promising since TPUs, as modifiers, offer a wide range of properties resulting from their segmented structure. Furthermore, they show partial miscibility with POM based on their ability to form hydrogen bonds between urethane group in polyurethane macrochain and ether linkage in polyoxymethylene backbone. To the other group of POM-based materials that has recently attracted considerable attention belong nanocomposites with layered silicates; both classes of nanostructured materials will be discussed.
Presentation: invited oral at E-MRS Fall Meeting 2005, Symposium E, by Krzysztof Pielichowski
See On-line Journal of E-MRS Fall Meeting 2005
Submitted: 2005-05-10 12:37 Revised: 2009-06-07 00:44