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In the present study, we provide a method for controlling the surface morphology of centrifugally spun starch-based fibers by adjusting the ratio of amylopectin/amylose in starches and combining with a hot blast temperature. The effects of hot blast temperature, amylopectin, and amylose on fiber surface morphologies are investigated. Scanning electron microscopy is used to characterize the morphology of the prepared fibers. The results show that fibers with burr-shaped nanostructures on the surface can be fabricated by adding amylopectin to starches and are promoted by increasing the hot blast temperature. However, amylose in starches plays the role of smoothing the fiber surfaces. X-ray diffraction reveals that the fibers are amorphous. Through Fourier transform infrared spectroscopy analysis, it was found that some physicochemical changes occur during centrifugal spinning. V C 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45810.

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We developed a new environmentally-friendly disposable nonwoven based on centrifugally spun ST/PVA ultrafine fibrous membrane in this research. The effects of ST/PVA ratio as well as formic acid post-treatment on thermal properties, tensile strength, and disposability of fibrous membranes were studied.To observe the morphology and chemical structures changing of fibers during fabrication and post-treatment, the obtained fibers were characterized by scanning electron microscopy, x-ray diffraction, and Fourier transform infrared spectroscopy. The fibrous membranes with uniform fiber diameters and excellent disposability properties were formed. The ST/PVA ratio of fibers was optimized according to the disposability and tensile strength of the fibrous membranes. Disintegration of untreated and post-treatment fibrous membrane with ST/PVA ratio of 3/1 was over 80% and 40%, respectively, and the tensile strength was improved over two times comparing with pure starch fibrous membrane.

Melamine microfibers were first prepared by centrifugal spinning. The stability and spinnability of a melamine-formaldehyde (MF) resin solution were improved as expected by adding various modifier combinations. Considering the storage stability of solutions characterized by visual inspection, turbidity tests, and viscosity measurements and combined with the fiber morphology, the optimal modifier combination was obtained. The spun fibers manifested a good morphology and thermal stability as measured by scanning electron microscopy, Fourier transform infrared spectroscopy, and thermogravimetric analysis. Moreover, microfibers prepared by three spinning methods (centrifugal spinning, electrospinning, and centrifugal electrostatic spinning) were compared to choose the suitable spinning method for different fields in the future. This work provides systematic and scientific guidance on the synthesis of MF resin solutions and rapid mass production of melamine microfibers and also demonstrates that centrifugal spinning of melamine microfiber is a promising candidate for flame retardance and CO 2 adsorption at elevated temperature. V C 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46072.

In this work, the authors prepared drug-loaded ultrafine starch/polyethylene oxide (PEO) fibres through centrifugal spinning, which use the poorly water-soluble drugs ibuprofen (ibu) and ketoprofen (ket) as model drugs. The obtained fibres were treated by acetic acid/glutaraldehyde solution (1/1, v/v) for 12 h at 40°C, in order to remove residual sodium hydroxide in fibres and improve the water stability. The morphology, chemical structures, and mechanical properties of obtained fibres were investigated. In-vitro drug release tests revealed that more than 75% of loaded drugs could be released from fibrous membranes without initial burst release (>80% in the first 2 h). The ibu-loaded fibrous membranes showed a sustained release period as long as 24 h, while the ket-loaded fibrous membranes could release more than 48 h. These fibre-based delivery systems are therefore proposed to be good candidate drug formulations, especially for improving solubility and bioavailability of poorly water-soluble drugs.

In this research, centrifugally spun ultrafine composite starch/polyvinyl alcohol (ST/PVA) fibers with high water stability were prepared by cross-linking with a mixture of glutaraldehyde and formic acid in the form of vapor phase. The effect of cross-linking temperature combined with time on the water stability, crystal structure, and thermal properties of fibers was investigated to obtain the optimum parameters. On this basis, we further prepared Ag-loaded ST/PVA fibers with different contents of nano silver. The structure and properties of Ag-loaded fibers, which cross-linked under the optimum parameters, were analyzed. As a result, the Ag-loaded fibers exhibited excellent water stability and mechanical properties and possessed inhibition zone diameters of 3 and 2 mm to Escherichia coli and Staphylococcus. aureus, respectively. The antibacterial property of the Ag-loaded ST/ PVA fibers provided a new route for developing less costly antibacterial fiber materials in the future.

This article reports the jet evolution process and fiber formation mechanism of the amylopectin rich starch solution in centrifugal spinning system, and the linear polyvinylpyrrolidone (PVP) is applied to compare with starch solution. The results indicate that jet evolution processes of starch solution include steady state and Rayleigh–Taylor instability over the whole concentration range for the spinnability investigation, which are due to the hyperbranched molecular of amylopectin. As a compression, the linear molecular chain PVP solution expresses a steady state jet under the spinning concentration. The spinnability results show that the obtained starch fibers are always containing the beads due to the Rayleigh–Taylor instability of jet, but can be effectively controlled by solution concentration and amylose/amylopectin. Instead, the PVP fibers show a rapid decreasing of beads till to almost disappear with the increasing of solution concentration, which due to the improvement of chain entanglement increase the steady state portion of jet with the increasing of concentration. The thermal properties of obtained fiber show that fibers obtained from amylose with more thermal stability.