![]() The framework was found to give a reliable ET value with an overall deviation of 0.26% and was also applicable to ET values of Reichardt, Nile red and HxQMBu2 indicators with an overall deviation of 1.73%, 0.36% and 0.40%, respectively. To validate the framework, the ET values of seventeen liquid nonpolar-polar mixtures, (ii) three CO2-expanded solvent mixtures and (iii) five scCO2-polar cosolvent mixtures collected from the literature were used. The HBD contribution factor can be simply estimated by a deviation of an actual ET value of pure HBD solvents from the homomorphism line. ![]() However, due to specific hydrogen bonding interactions of the phenol blue with polar hydrogen bond donor (HBD) solvents, the ET framework for binary mixtures of nonpolar solvent with polar HBD solvent was the modification by the addition of HBD contribution factor. The equations of the ET framework for binary mixtures of nonpolar solvent with polar hydrogen bond acceptor (HBA) solvent can be directly adopted from the previous framework for Kamlet-Taft dipolarity/polarizability (KT-π*) because of the linearity of the homomorphism line between ET and KT-π* for pure nonpolar solvents and pure polar HBA solvents. In this work, a predictive framework is proposed for estimating ET values of phenol blue indicator in three mixed-solvent systems as (i) liquid nonpolar-polar mixtures, (ii) CO2-expanded liquid solvent and (iii) supercritical carbon dioxide (scCO2)-polar cosolvent mixtures. Solvatochromic parameter of electronic transition energy (ET) provides information on dipolarity/polarizability and hydrogen bonding donor interactions in the solvation shell. It showed a good ability to form porous matrices, while its thermal stability somewhat decreased. ![]() The obtained polymer was examined by SEM and TG. It was found that even with relatively low concentrations of hydrogen peroxide and short processing times, it is possible to obtain chitosan oligomers with a molecular weight of about 14 kDa. The resulting chitosan decomposition product was analyzed by a number of analytical methods, such as IR spectroscopy, UV–vis spectroscopy, X‐ray photoelectron spectroscopy, high resolution mass spectrometry, and X‐ray diffraction. This medium contains self‐neutralizing carbonic acid used here to dissolve chitosan as well as peroxycarbonic acid formed from aqueous hydrogen peroxide, which acts as an oxidizing agent strong enough to break the glycosidic bonds of chitosan. In the present work, the possibility of chitosan decomposition in the presence of peroxycarbonic acid solutions under high CO2 pressure was investigated. In the scenario of deproteinized NR (DPNR) latex containing 10% DRC, 20% w/w H2O2, and TiO2 film coated on a quartz substrate, the HTNR could be manufactured effectively.Īn important scientific task is the search for inexpensive and environmentally friendly methods for the production of chitosan oligomers. A unique diffraction peak for the anatase (101) phase could be observed in the TiO2 film deposited on the quartz substrate, resulting in photochemical activity and photocatalytic efficiency significantly higher than those of the substrate made of glass. After the reaction, the properties of the rubber products, including intrinsic viscosity, molecular weight, and microstructure, were determined. In addition, the influence of several factors, such as rubber and surfactant concentrations, on the reaction was investigated. X-ray diffraction (XRD) spectroscopy and atomic force microscopy (AFM) were applied to investigate the TiO2 deposited on glass and quartz substrates. ![]() To enhance the effectiveness of the process, a quartz substrate was placed on the TiO2 film-coated substrate for photochemical breakdown. Nevertheless, light energy is wasted during the photodegradation process because a glass substrate has a cutoff for ultraviolet light. Photochemical degradation using a TiO2 film that has been deposited on a glass substrate is one of the fascinating methods of producing HTNR. Hydroxyl-terminated natural rubber (HTNR) is a product of interest for making natural rubber (NR) easy and versatile for use in a wide range of applications. ![]()
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