The drop size is of fundamental importance in the design of liquid-liquid extraction columns, the drop size was measured as a function of the geometry, operating conditions, and physical properties of a liquid-liquid system with no mass transfer in a five-stage modified Scheibel extraction column. An improved correlation of the mean drop size in the Scheibel extraction column is presented. The correlation was divided into three sections in terms of the Reynolds number. It could be applied in a wide range and could be further used for the study of mass transfer performance of the modified Scheibel extraction column.

The polymerization of tetrahydrofuran (THF) was carried out in CH₂Cl₂ by using phosphotungstic heteropolyacid as initiator and epichlorohydrin as promoter. This cationic ring-opening polymerization process was monitored by in situ mid-infrared spectroscopy system (ReactIR) to further study the thermodynamics and kinetics of THF polymerization. It was observed that the sharp infrared peak of COC stretching vibrations will shift from about 1068 to 1109 cm⁻¹ in THF ring-opening step. The changes in absorbance intensity of the two characteristic peaks were used for determining instantaneous concentration of linear polymer and ring monomer. The experimental results demonstrated that the kinetics of THF polymerization proved to be typically first-order. Thermodynamic parameters were determined from the temperature dependence of the monomer equilibrium concentration [M]_e over the range from −5 to 25°C. The values of k_app were obtained via the plots of ln{([M]₀−[M]_e)/([M]_t−[M]_e)} vs reaction time, for polymerization under specific conditions. The apparent activation energy (E_a) and frequency (A) were determined from the Arrhenius plot of k_app vs. T⁻¹. Besides, the in situ kinetic investigation revealed that more chain-transfer occurred at higher temperatures, leading to a reduction in propagation species concentration and a deviation from first-order propagation at the later stage of polymerization. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40503.

Experiments were designed to ascertain the main factors for the Sauter mean drop size (d₃₂) of the dispersed phase in a three-stage modified Scheibel extraction column with no mass transfer. A precise correlation applied to the liquid-liquid systems with low interfacial surface tension was proposed for calculating d₃₂. The maximum relative error for all data was 16.0 % and the mean relative error ±4.6 %.

Amino polysiloxanes (APSs) with different amino values and amino types were synthesized and applied to cotton fabrics. Softening and smoothening properties of the fabrics treated with APSs were investigated and evaluated by measuring wrinkle recovery angles and friction coefficients, and the morphological features of the APSs adsorbed onto cellulose substrate films were characterized by atomic force microscope (AFM). The results indicate that the amino values and amino types of the APSs have a significant impact on the softening and smoothening properties of the fabrics. APSs with relatively high amino values exhibit superior smoothening property, while APSs with moderate amino values exhibit excellent softening property. Compared to the traditional softener N-β-aminoethyl-γ-aminopropyl polydimethylsiloxane (APS-1), the new amino type softeners γ-piperazinylpropyl polydimethylsiloxane (APS-2) and N-γ'-dimethylaminopropyl-γ-aminopropyl polydimethylsiloxane (APS-3) gave better fabric performance, whereas aminopropyl polydimethylsiloxane (APS-4) and N-cyclohexyl-γ-aminopropyl polydimethylsiloxane (APS-5) gave unsatisfactory fabric performance. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011