JOURNAL OF APPLIED POLYMER SCIENCE
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2019
·Vol. 137
·期 19
·48671
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IF 2.188
Huiqing Wei,Xidong Suo,Chunxiang Lu,Yaodong Liu
The fiber spinning methods determine the formation of the physical structures of polyacrylonitrile (PAN) fibers which further affect stabilization reactions and the mechanical performances of the resultant carbon fibers. In this study, PAN fibers were prepared by both dry-jet gel spinning (g-PAN) and dry-jet wet spinning (w-PAN), and their stabilization behaviors were compared. While the stabilized w-PAN fibers show sheath-core structures, the stabilized g-PAN fibers exhibit relatively uniform stabilized structures along the radial direction. Additionally, the stabilization reactions of g-PAN fibers occur faster than that of w-PAN fibers, and the cyclization, oxidation, and crosslinking reaction activation energies of g-PAN fibers are lower than that of w-PAN fibers, respectively. Moreover, the carbon yield of g-PAN is higher than that of w-PAN fibers. We believe that above changes are possibly ascribed to the formation of different PAN sheath structures and oriented chain structures during dry-jet wet spinning and dry-jet gel spinning. It is concluded that gel spinning could significantly reduce the sheath-core difference of PAN fibers and the stabilized fibers as compared with wet spinning, which leads to a faster stabilization and more uniform stabilized structures. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 137 , 48671.
研究领域:
材料科学
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高分子科学
·
纤维科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2017
·Vol. 134
·期 15
·
IF 1.86
Yaofang Fan,Xie Quan,Huimin Zhao,Shuo Chen,Hongtao Yu,Yaobin Zhang,Qi Zhang
In this study, an antifouling poly(vinylidene fluoride) (PVDF) hollow-fiber membrane was fabricated by blending with silver-loaded graphene oxide via phase inversion through a dry-jet, wet-spinning technique. The presence of graphene oxide endowed the blended membrane with a high antifouling ability for organic fouling. The permeation fluxes of the blended membrane was 3.3 and 2.9 times higher than those of a pristine PVDF membrane for filtering feed water containing protein and normal organic matter, respectively. On the other hand, the presence of silver improved the antibiofouling capability of the blended membrane. For the treatment of Escherichia coli suspension, the permeation flux of the blended membranes was 8.2 times as high as that of the pristine PVDF membrane. Additionally, the presented blended membrane improved the hydrophilicity and mechanical strength compared to those of the pristine PVDF membrane, with the water contact angle decreasing from 86.1 to 62.5° and the tensile strength increasing from 1.94 to 2.13 MPa. This study opens an avenue for the fabrication of membranes with high permeabilities and antifouling abilities through the blending of graphene-based materials for water treatment. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 44713.
研究领域:
材料科学
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环境工程
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膜技术
·
纳米技术
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产品关联
DOI
高影响因子
NEW CARBON MATERIALS
·
2019
·
IF 1.387
Xiao-peng Li,Xi-dong Suo,Yao-dong Liu,Yong-hong Li
The use of gel spinning technology in the formation of polyacrylonitrile (PAN)-based carbon fibers has led to significant tensile property improvements. PAN, dimethylsulfoxide (DMSO) and dimethylformamide (DMF) solutions were dry-jet spun, gelled in methanol at −20 and −50 °C for different times from 0 to 40 d, and vacuum-dried at 0 °C for 24 h to obtain PAN fibers that were drawn to a drawing ratio (DR) of 4 in a hot glycerin bath at 110 °C, and then to various DRs in a glycerin bath at 155 °C. The effects of gelation time on the microstructures, mechanical properties and cyclization reactions of the gel-spun PAN fibers were investigated. Results showed that the gelation time affected the gel structure and the maximum possible draw ratio. The gelation effects were significant in the first 5-10 d, and were more prominent for the DMSO system than the DMF system. The maximum possible draw ratio, strength and modulus, orientation and crystallinity of the PAN fibers increased with gelation time. The cyclization temperature decreased and the reaction enthalpy increased with gelation time in cyclization, indicating an improved chain orientation and crystallinity with gelation time. Gelation was an important step affecting the microstructures and properties of gel-spun PAN fibers for making high performance carbon fibers.
研究领域:
材料科学
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高分子科学
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纺织工程
✓ 已验证
产品关联
DOI
高影响因子
COMPOSITES SCIENCE AND TECHNOLOGY
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2014
·
IF 3.633
Huyan Shi,Fu Liu,Lixin Xue,Huafeng Lu,Qingbo Zhou
Ag-loaded zeolites were synthesized and embedded into the outer layer of poly(vinylidene fluoride) (PVDF) dual-layer hollow fiber membrane (D) using a dry-jet wet-spinning co-extruding technique. The distribution of the Ag-loaded zeolites in the outer layer was confirmed by field emission scanning electron microscopy (FE-SEM) and energy-dispersive X-ray spectroscopy (EDX). It was found that the D contained only 54% of the amount of Ag-loaded zeolites that were distributed throughout the cross section of PVDF single-layer hollow fiber membrane (S), as calculated by thermogravimetric analysis (TGA). However, D showed excellent antibacterial efficiency and resistance to bacterial adhesion because of the higher concentration of Ag + in the outer layer of the membrane. The surface morphologies , pure water flux, mean pore size, pore size distribution , and thermal stability of both PVDF membranes were also investigated.
研究领域:
材料科学
·
化学工程
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）