23 KB425 KB20 KB200020242012Junkar, ItaKreuh, DarijKucharczyk, PavelSáha, PetrSedlařik, Vladimirštevilka:1letnik:46str. 37-41ISSN:1580-2949COBISSID:29690841URN:URN:NBN:SI:doc-Y4EDKERXenInštitut za kovinske materiale in tehnologijeMateriali in tehnologijeCalorimetry, Differential ScanningCaproatesCatalysisChromatography, GelKalorimetrija diferencialna, vrstičnaKaproatiKatalizaKromatografija, gelLactic AcidMlečna kislinaMolecular WeightMolekulska masapolikondenzacijaSpectroscopy, Fourier Transform InfraredSpektroskopija Fourierjeva, transformacijska, infrardečaVacuumVakuumEnhancement of molecular weight of L-lactic acid polycondensates under vacuum in solid state| Povečanje molekularne teže polikondenzatov L-laktične kisline v trdnem stanju z vakuumom|Enhancement of L-lactic acid polycondensates by involving of postpolycondensation reactions in solid state under vacuum and catalyzed by stannous 2-ethylhexanoate were studied in the presented work. The catalyst wasused only in postpolycondensation step. An effect of the catalyst concentration and postpolycondensation reaction time on resulting properties of poly(lactic acid) was studied by gel permeation chromatography, Fourier transform infrared spectroscopy and differential scanning calorimetry. Resultsshow significant enhancement of molecular weight in case of the systemscontaining 2 wt. % of the catalyst due to the postpolycondensation procedure (Mwč91.0 kg/mol; i.e. 1655 % after 24 hours). However, further progress can be assumed with increasing reaction time. This enhancement of poly(lactic acid) molecular weight had a response corresponding to changes of both physico-chemical and thermal properties of the solid state postpolycondensation productsTEXTznanstveno časopisjejournalsSlovenian National E-content AggregatorNational and University Library of SloveniaInštitut za kovinske materiale in tehnologije