Copolyesters based on isosorbide and butanedioic acid in combination with monomers such as adipic acid and dimethyl terephthalate, poly(isosorbideco-butanedioic acid) (and -co-adipic acid) and poly(isosorbide-co-butanedioic acid-co-dimethyl terephthalate), were synthesized and characterized. Linear OH-functionalized polyesters were obtained via melt polyesterification of dicarboxylic acids with OH-functional monomers. The type of end-group was controlled by the monomer stoichiometry and hydroxyl functional group is formed in time. Average molecular masses of synthesised polyesters were measured by gel permeation chromatography. The glass transition temperatures and thermal stability of the obtained polyesters were effectively adjusted by varying polymer composition and molar mass. Addition of adipic acid or dimethyl terephthalate increased glass transition temperatures of obtained polyesters. Thermal stability of obtained polyester slightly increases by the increasing of dimethyl terephthalate content. Molecular structures of obtained polyester were assessed by Fourier transform infrared spectra and 1 H NMR spectroscopy.

Characterization of films based on cellulose acetate/poly(caprolactone diol) intended for active packaging prepared by green chemistry principles. ACS Sustainable Chemistry & Engineering, published online on 7 July 2022.

The main aim of this work was to obtain conductive polymer-based materials by incorporation of different amounts of multiwalled carbon nanotubes (MWCNTs) into poly(lactide)(PLA) using the electrospinning technique. Fiber-based nonwovens with 0.2, 0.5, 1, and 3 wt% of MWCNTs were characterized regarding conductivity, morphology, thermal, and mechanical properties. It was confirmed that an increase of the MWCNTs content does not influence the increase of the material conductivity, since the conductivity was 170 ohm sq 1 for all composites. Scanning electron microscopy and transmission electron microscopy analyses revealed that smooth and beadless fibers were obtained, but also average diameters of composite nanofibers decreased with the increase of the MWCNTs content. Differential scanning calorimetry analysis showed that the presence of MWCNTs in the PLA matrix had a significant influence on the crystallization behavior of PLA nanofibers, because the decrease in crystallization temperature (Tc) was detected. Also, the incorporation of MWCNTs into PLA fibers affected the melting process, enabling the generation of α ' form, while had no influence on ordered α crystal. The enthalpy of composite degradation decreased, because MWCNTs are well-known for good heat conductivity, and with that the second step of degradation slowed down, as it was confirmed by thermogravimetric analysis. The

No abstract