Mechanical and thermal properties of composite polymer materials strongly depend on their local structure and molecular dynamics which can be effectively studied by the solid-state nuclear magnetic resonance (NMR) techniques. In the present paper, the influence of formamide (F) and sorbitol (S) plasticizers on molecular motion in thermoplastic starch (TPS) was studied using solid-state NMR spectroscopy and dynamic mechanical thermal analysis (DMTA). DMTA measurements carried out for formamide-(F-TPS) and sorbitol-plasticized (S-TPS) corn starches indicated heterogeneous plasticizer distribution of plasticizer-rich and starch-rich phases within the samples. The single pulse and cross-polarization 13 C NMR spectra measured for both plasticized starches confirmed the amorphous character of their structure and distinctly different chain mobility supported by the values of 13 C spin-lattice relaxation times. The results of the analysis of broad line and magic angle spinning 1 H NMR spectra are in accordance with the results of DMTA measurements, revealing lower mobility of starch chains within S-TPS in comparison to F-TPS. Crosslinking of the starch chains with sorbitol molecules was suggested as being responsible for the lower mobility of the starch chains in S-TPS.
Thermodynamic and transport properties of the CaRu1–xTixO3 system with x = 0, 0.03, 0.07, 0.10, and 0.15 in magnetic field up to 9 T have been studied. The unconventional temperature dependences of magnetic susceptibility, specific heat, and electrical resistivity observed for CaRuO3 are typical for non‐Fermi liquids and they support the assumption about the proximity of the system to the quantum critical point. The analysis of the experimental results suggests the electronic phase separation in CaRuO3 into ferromagnetic itinerant regions coexisting with strongly correlated ones. Substitution by titanium seems to push the system towards ferromagnetism, and drives it away from the quantum criticality.
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