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Chains containing side groups were generated with up to 102 bonds in the backbone for both iso- and syndiotactic arrangements. The mean-square end-to-end distance , the mean-square radius of gyration and the ratios / of the axes of inertia were investigated. It could be shown that the mean size and shape of such chains are not influenced by the kind of stereoregularity.

The self-aggregation of sodium perfluorooctanoate (SPFO) has been studied by pH, ion-selective electrodes, changes in Rhodamine 6G colour and fluorescence, conductivity, surface tension and viscosity measurements. It has been determined that the aggregation of SPFO is gradual. It starts to aggregate at 0.01 mol dm−3 with the formation of pre-micelles of perfluorooctanoate ions, which capture counterions at C=0.02 mol dm−3 and form micelles at a critical micelle concentration (CMC) of 0.03 mol dm−3. Micelles at the CMC are highly ionised and strongly hydrated. At C*=0.06 mol dm−3, a low ionisation degree was found, indicating the formation of a more compact micellar structure. Micelles at the CMC show energetic advantage in comparison with the adsorbed state at the air/solution interface, and this advantage increases at C* originating desorption.

The rheological behavior and gelation characteristics of epoxy blends are of critical importance to property study and industrial application. In this work, we studied the rheological behavior and structural transition of different thermoplastics, including polyetherimide, polymethylmethacrylate, and polyethersulfone (PES), modified epoxy systems by using rheometry instrument, differential scanning calorimetry, time-resolved light scattering, and scanning electronic microscopes. At the same molecular weight level of thermoplastics, different epoxy blends show profound diversities on the rheological and gelation behavior due to the large differences in phase separation and curing process. For early phase-separation systems of PES-modified epoxy blends, two gel points are identified, which correspond to physical gelation and chemical gelation, respectively. With the variation of the PES molecular weight and curing rate, dramatic changes in gel time and critical exponent were observed. As the molecular weight of thermoplastics is increased, the gelation time becomes shorter and the gel strength gets lower, while the faster curing rate would increase the physical gel strength significantly.

The interaction of anionic surfactants with serum albumin has emerged as an important area of research and is considered as a model for gaining fundamental insight into surfactant-protein binding, which is useful in both chemical and biological applications. This study involves the interactions of three synthesized proline-based anionic surfactants of varying chain lengths (C8, C10, and C12) with bovine serum albumin (BSA) using different techniques, including fluorescence, 1H NMR, and FT-IR spectroscopy. The study indicated that the binding of the proline surfactants with BSA followed a static quenching process, with an increase in binding ability upon increasing chain length. FT-IR studies revealed a change in the secondary structure of BSA upon binding with the proline surfactant, while 1H NMR investigations indicated the proximity of the long alkyl chain of the surfactant with tryptophan residues of BSA. Molecular docking studies performed on the three proline surfactants with BSA revealed that the surfactants were able to bind in the vicinity of both tryptophan residues (Trp-213 and Trp-134) with an increase in the free energy of binding while increasing the chain length from C8 to C12. Therefore, this study provided a whole view about the interaction of BSA with anionic proline derived surfactants, which can be used as potential ingredients in pharmaceutical products.