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Wang X.-J.,Shandong DongYue Polymer Material Co. | Fang S.-X.,Shandong DongYue Polymer Material Co. | Zhang Y.-M.,Shandong DongYue Polymer Material Co. | Zhang Y.-M.,Shanghai JiaoTong University
Xiandai Huagong/Modern Chemical Industry | Year: 2013

Statistical research on fluorine containing products and materials is performed. Based on the statistical data of issued-patents, the national standards of fluorine containing materials are analyzed. The standards of fluorinated materials are mainly focused on PTFE and its application, while the standards of basic fluorine containing products are focused on properties and analytical methods. The statements of fluorine industry and standardization work in the "Twelfth Five-Year Guideline" are summarized and the problems in standard setting are discussed. It is pointed out that technical patent and standardization of patent are an effective way to promote the technical innovation and achievement transformation. Source

Wang L.,Shandong Huaxia Shenzhou New Material Co. | Wang X.-J.,Shandong DongYue Polymer Material Co. | Chen Y.,Shandong Huaxia Shenzhou New Material Co.
Xiandai Huagong/Modern Chemical Industry | Year: 2013

The current progresses of perfluorinated ion exchange resin at home and abroad are reviewed. The preparation of new fluoromonomers and new fluoropolymeric resins and their development directions are introduced. The prospects of the research and application of perfluorinated ion exchange resin are proposed as well. Source

Xu A.,Shanghai JiaoTong University | Yuan W.Z.,Shanghai JiaoTong University | Zhao J.,Shanghai JiaoTong University | Li H.,Shanghai JiaoTong University | And 2 more authors.
Journal of Applied Polymer Science | Year: 2012

Tetrafluoroethylene (TFE) and perfluoropropylvinyl ether (PPVE) were copolymerized in supercritical carbon dioxide (sc-CO 2) with a perfluorodiacyl initiator bis(perfluoro-2-n-propoxypropionyl) peroxide (BPPP). The resultant copolymers with stable perfluoroalkyl end groups were obtained, avoiding the decomposition during processing and applications. Reactivity ratios of TFE and PPVE were first reported. The r TFE and r PPVE values are about 8 and 0.08, respectively. Such parameters are significant for the modification of PTFE through copolymerization of TFE and PPVE. It is found that through increasing the reaction pressure from 8.5 to 25 MPa, while r TFE increases by 12.0%, r PPVE decreases by 9.0%, which should be ascribed to the enhancement of the polarity of CO 2 under high pressures. Because the reactivity of TFE is by two orders of magnitude higher than that of PPVE; on one hand, the copolymerization rate falls rapidly with the decrease of TFE feed ratio; on the other hand, TFE content in the copolymer decreases with the reaction time. All copolymers containing different fractions of PPVE enjoy outstanding thermal stability. The DSC result indicates that there exist two forms of crystals with highly regular molecular arrangement or less ordered chain packing which is disturbed by perfluoropropyl pendants. © 2011 Wiley Periodicals, Inc. Source

Wang J.,Shanghai JiaoTong University | Wang X.,Shandong DongYue Polymer Material Co. | Dou P.,Shandong DongYue Polymer Material Co. | Zhang H.,Shandong DongYue Polymer Material Co. | Zhang Y.,Shanghai JiaoTong University
Polymer Engineering and Science | Year: 2015

A melt-extruded method has been used to prepare blend membranes of Perfluorosulfonic Acid Polymer (PFSA) and Perfluorocarboxylic Acid Polymer (PFCA) with different combination ratios. Fourier Transform Infrared (FT-IR) and X-ray Diffraction (XRD) analyses have showed that the chemical structure and crystallization behaviour of both polymers remained unchanged in the blend membrane, and the crystallinity has been increased for the blend membrane with a higher weight fraction of PFCA. According to the results obtained from Scanning Electron Microscope (SEM), PFSA and PFCA polymers are well compatible, forming mixed aggregates containing both sulphonyl and carboxyl ions. Surprisingly, a membrane containing a 50:50 ratio of PFSA/PFCA has showed microphase separation, and it possesses the smallest ionic cluster size among all the blend membranes prepared, as illustrated by the Small Angle X-Ray Scattering (SAXS) analysis. In addition, when the PFCA content was increased, the ion exchange capacity (IEC) for blend membranes remained the same, while their water uptake and proton conductivity have decreased rapidly. Compared with the PFSA/PFCA two-layered membrane, this PFSA/blend/PFCA membrane not only maintained respectable electrolysis property, also exhibited significantly higher peel strength, especially after the hydrolization process; plus, it has showed excellent resistance to the peeling damage under the operational conditions of chlor-alkali electrolytic cells. © 2014 Society of Plastics Engineers. Source

Zhao J.,Shanghai JiaoTong University | Xu A.,Shanghai JiaoTong University | Yuan W.Z.,Shanghai JiaoTong University | Gao J.,Zhengzhou University | And 4 more authors.
Journal of Materials Science | Year: 2011

Electrospinning performance of 5-52 wt% perfluorosulfonic acid (PFSA), poly (N-vinylpyrrolidone) (PVP), and PFSA/PVP blends in N,N-dimethylformamide (DMF) with various PFSA/PVP ratios were systematically investigated in respective of solutions properties, mainly surface tension and rheological properties. Mechanical relaxation time sM calculated from rheological results happens to be closely correlated with nanofiber morphology, and is used to evaluate the electrospinnability. Polymer solutions with higher sM show better electrospinnability. Morphologies of the electrospun samples were observed by Scanning electronic microscopy. The results show that the pure PFSA solutions, even with a quite high concentration up to 52 wt%, fail to be electrospun and possess a very low sM. Addition of PVP improves electrospinnability of PFSA and increases sM. The electrospinnability of PFSA/PVP/ DMF solutions can be manipulated by changing the ratio of PFSA to PVP and the total polymer concentration of the mixed solutions. The PFSA nanofiber mats with a small fraction of PVP (\8 wt%) with the average diameter of 370 nm were successfully obtained. © Springer Science+Business Media, LLC 2011. Source

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