Thermal stability of segmented polyurethane elastomers reinforced by clay particles

The aim of this work was to determine the influence of clay nanoparticles on thermal properties of segmented polyurethanes based on hexamethylene- diisocyanate, aliphatic polycarbonate diol and 1,4-butanediol as chain extender. The organically modified particles of montmorillonite and bentonite were used as reinforcing fillers. The structure of elastomeric materials was varied either by diol type or chain extender content. The ratio of OH groups from diol and chain extender (R) was either 1 or 10. Thermal properties of prepared materials were determined using modulated differential scanning calorimetry (MDSC). Thermal stability of obtained elastomers has been studied by simultaneously thermogravimetry coupled with DSC. The glass transition temperature, Tg, of soft segments for all investigated samples was about -33?C. On the basis of DTG results, it was concluded that obtained materials were very stable up to 300?C. Cilj ovog rada je bio ispitivanje uticaja nanocestica gline na toplotna svojstva segmentiranih poliuretana dobijenih reakcijom polikarbonatnog diola, heksametilen-diizocijanata i produzivaca lanca 1,4-butandiola. Organski modifikovane cestice montmorilonita i bentonita su koriscene kao punioci za ojacanje elastomera. Struktura dobijenih materijala je varirana ili promenom sadrzaja produzivaca lanaca ili tipom polikarbonatnog diola. Odnos OH grupa iz diolne komponente i OH grupa iz produzivaca lanca (R) bio je 1 ili 10. Toplotna svojstva materijala su odredjena koriscenjem modulovane diferencijalne skenirajuce kalorimetrije (MDSC). Termicka degradacija je pracena simultanom diferencijalnom skenirajucom kalorimetrijom i termogravimetrijom koja istovremeno prati i promenu protoka toplote i gubitka mase. Temperatura prelaska u staklasto stanje, Tg, mekih segmenata elastomera iznosila je oko -33?C. Na osnovu termogravimetrijskih rezultata, ustanovljeno je da su dobijeni materijali veoma stabilni do 300?C.