Ceramics-Silikáty 57 (2) 120-125 (2013)

MACRO DEFECT FREE MATERIALS; MECHANOCHEMICAL ACTIVATION OF RAW MIXES AS THE INTENSIFYING TOOL OF THE ENTIRE MDF SYNTHESIS

Drábik M., Gáliková Ľ., Billik P., Maier G., Kosednar-Legenstein B.

A challenge in the field of MDF materials, which has not been followed or indicated by now, are the options of improvement of cross-linking through intensified mixing of dry MDF raw mixes of cement and polymer. The potential of mechanochemical treatment to intensify the atomic level of cross-linking already in the raw mixes and, thus, the activation of raw mixes has been critically verified earlier. Processes of the mutual MDF syntheses of both standard and activated raw mixes are presented and discussed in this paper. The scope of cross-linking as a key item of the successful MDF synthesis has been studied by two independent experimental methods – thermal analysis and IR spectroscopy. The knowledge has been achieved about (i) phenomenon of internal pressure during MDF synthesis from mechanochemically activated raw mixtures and (ii) increase of the content of cross-links by one third in MDF materials synthesized from mechanochemically activated raw mixtures in comparison with these synthesized from standard raw mixtures. Mechanochemical activation of raw mixtures undoubtedly leads to the intensification of cross-linking in MDF materials; if applied (prior to water addition and pressure application) it increases the rate of cross-links formation in the system through the effect of internal pressure. The reported approach and results represent besides the contribution to the knowledge about MDF materials themselves also the challenge for the development of a variety of new and innovative materials strategies.

Keywords: Macro-defect-free materials, Mechanochemical activation, Synthesis, Al(Fe)-O-P cross-links