1-Butyl-3-methylimidazolium chloride ([BMIM]Cl) was used as a solvent for cellulose, the rheological behavior of the cellulose/[BMIM]Cl solution was studied, and the fibers were spun with a dry-jetwet-spinning process. In addition, the structure and properties of the prepared cellulose fibers were investigated and compared with those of lyocell fibers. The results showed that the cellulose/[BMIM]Cl solution was a typical shear-thinning fluid, and the temperature had little influence on the apparent viscosity of the solution when the shear rate was higher than 100 s À1 . In addition, the prepared fibers had a cellulose II crystal structure just like that of lyocell fibers, and the orientation and crystallinity of the fibers increased with the draw ratio increasing, so the mechanical properties of the fibers improved. Fibers with a tenacity of 4.28cN/dtex and a modulus of 56.8 cN/dtex were prepared. Moreover, the fibers had a smooth surface as well as a round and compact structure, and the dyeing and antifibrillation properties of the fibers were similar to those of lyocell fibers; however, the color of these dyed fibers was brighter than that of lyocell fibers. Therefore, these fibers could be a new kind of environmentally friendly cellulose fiber following lyocell fibers.

Crystallization is widely utilized as a purification technique in industries. Frequently in the course of crystallization, oiling-out, or termed liquid–liquid phase separation (LLPS), occurs and strongly influences the morphology of crystals. To research how to control and optimize the crystal habits when there is oiling-out, we investigated the β-alanine–water–isopropanol ternary system. Four ternary phase diagrams at 25, 30, 35, and 40 °C were constructed to provide a thermodynamic basis and guidance for the crystallization process. Moreover, to fully analyze the LLPS nucleation mechanism of β-alanine, the tie lines of the ternary diagram were constructed, and the site of nucleation was determined. Besides, on the basis of the phase diagram, evaporative crystallization was performed to investigate oiling-out crystallization. Furthermore, tabular crystals, octahedron shaped crystals, and spherical crystals were obtained respectively from normal crystallization, oiling-out crystallization, and quasi emulsion solvent diffusion crystallization.

A defect engineering strategy is proposed to synthesize carbon foam supported oxygen vacancy-enriched SnOx nanosheets as a promising monolithic electrode for electrocatalytic reduction of CO2 to formate with high activity and selectivity.

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The flax and equivalent proportion of poly(l‐lactic acid)/poly(d‐lactic acid) (PLLA/PDLA) were melt compounded and injection molded to prepare flax‐reinforced polylactide stereocomplex (sc‐PLA) bio‐composite, and the effect of alkali treatment on the structure and properties of flax as well as the flax/sc‐PLA composite was investigated. SEM and FTIR results showed hemicellulose in flax was almost completely removed after alkali treatment and the treated flax (ALK‐flax) bundles were more separated with a cleaner surface than untreated flax (UN‐flax). DSC results showed homo‐crystallites (hc, Tm = 160–170°C) and stereocomplex crystallites (sc, Tm ∼210°C) coexisted in sc‐PLA and flax/sc‐PLA composites. Compared with sc‐PLA, the total crystallinity and sc‐crystallinity of flax/sc‐PLA composite increased regardless of whether the flax were treated with alkali, whereas ALK‐flax/sc‐PLA composite showed a little higher crystallinity than UN‐flax/sc‐PLA composite. TGA results confirmed ALK‐flax/sc‐PLA composite had a higher thermal degradation temperature than UN‐flax/sc‐PLA composite. The mechanical tests indicated although the mechanical properties of sc‐PLA increased significantly by reinforcing with flax, the ALK‐flax/sc‐PLA composite showed little lower mechanical properties than UN‐flax/sc‐PLA composite. The alkali treatment of flax had no obvious influence on the Vicat softening temperature (VST) of flax/sc‐PLA composites, a higher heat resistance with VST at ∼155°C could be obtained for flax/sc‐PLA composite. POLYM. ENG. SCI., 55:2553–2558, 2015. © 2015 Society of Plastics Engineers