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Synthetic model triacylglyceride oils are important compounds for applications in pharmaceutical and food chemistry. Herein, a practical and highly efficient methodology for the synthesis of saturated and unsaturated triacylglycerides utilizing saturated and unsaturated fatty acids activated by 1,1'‐carbonyldiimidazole (CDI) has been developed and applied in the synthesis of deuterated medium chain triglyceride (MCT) oil for studies of plant‐based and diary food emulsions. The deuterium labelled compounds were used to gain new insight into the mechanism of the reaction, which was confirmed by density‐functional theory (DFT) calculations. [ABSTRACT FROM AUTHOR]

Semi‐crystalline polymers exhibit microphase separation into crystalline and amorphous domains characterized by multiple structural levels with sizes ranging from ångströms to hundreds of nanometres. The combination of small‐angle (SANS) and wide‐angle (WANS) neutron scattering on the same beamline enables reliable in situ characterization of such materials under application‐relevant conditions, with the unique advantage of contrast variation by controlled labelling, allowing the structure of such multi‐component systems to be resolved in detail. This paper reports a structural analysis performed on deuterated polymer membranes based on syndiotactic polystyrene (sPS) using an extended Q‐range SANS and WANS combination, always with the same neutron scattering instrument, either a pinhole SANS diffractometer installed at a research reactor or a 'small‐ and wide‐angle' time‐of‐flight diffractometer installed at a neutron spallation source. sPS is a semi‐crystalline material that becomes hydrophilic and proton conducting when suitable functionalization is achieved by thin film sulfonation, and can form various co‐crystalline complexes (clathrates) with small organic molecules stored in the crystalline phase as guests in the vacancies between the polymer helices. Therefore, this material is interesting not only for its conducting properties but also for its versatility as a model system to evaluate the usefulness of extended Q‐range neutron scattering in such studies. Variation of neutron contrast was achieved in the amorphous hydrophilic phase by using H2O or D2O to hydrate the membranes and in the crystalline phase by loading the clathrates with deuterated or protonated guest molecules. The experimental approach, the advantages and limitations of the two types of instrumentation used in such analyses, and the main results obtained with respect to the structural characterization of sulfonated sPS membranes under different hydration and temperature conditions are reported, and the potential of this method for similar structural studies on other semi‐crystalline polymeric materials is discussed. [ABSTRACT FROM AUTHOR]

Syndiotactic polystyrene (sPS) is a crystalline polymer which has a unique property; it is able to form cocrystals with a wide range of chemical compounds, in which the guest molecules are confined in the vacancies of the host sPS crystalline region. Recently, it has been found that even polyethylene glycol oligomers with a molecular weight of more than several hundreds can be introduced into the sPS crystalline region. It is quite important to know how such a long-chain molecule is stored in the host sPS lattice. To tackle this issue, a new simultaneous measurement method combing small-angle neutron scattering and Fourier transform infrared spectroscopy (SANS/FTIR), which has been recently developed by the authors, was applied to an sPS cocrystal with polyethylene glycol dimethyl ether with a molecular weight of 500 (PEGDME500). The temperature-dependent changes of the SANS profile and FTIR spectrum were followed from room temperature up to 413 K for a one-dimensionally oriented SANS/PEGDME500 cocrystal sample. The intensity of the reflections due to the stacking of crystalline lamellae showed a significant temperature dependence. The two-dimensional pattern in the high Q region of SANS also changed depending on temperature. The combined information obtained by SANS and FTIR suggested that PEGDME500 molecules are distributed in both the crystalline and amorphous regions in the low-temperature region close to room temperature, but they are predominantly included in the amorphous region in the high-temperature region. It was also suggested by the two-dimensional SANS profile that PEGDME500 molecules in the crystalline region have an elongated structure along the thickness direction of the crystalline lamellae. [ABSTRACT FROM AUTHOR]