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Synergistic Effect of Atmospheric Pressure Plasma Pre-Treatment on Alkaline Etching of Polyethylene Terephthalate Fabrics and Films

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Plasma Science and Technology 2016年第4期18卷 346-352页

作者： Amel E.A.ElabID 郭颖石建军丁可张菁 state key laboratory for modification of chemical fibers and polymer materials College of Material Science and EngineeringDonghua University state key laboratory for modification of chemical fibers and polymer materials College of ScienceDonghua University

Dyeing of PET materials by traditional methods presents several *** technology has received enormous attention as a solution for the environmental problems related with textile surface modifications,and there has been a rapid development and commercialization of plasma technology over the past *** this work,the synergistic effect of atmospheric pressure plasma on alkaline etching and deep coloring of dyeing properties on polyethylene terephthalate（PET）fabrics and films was *** topographical changes of the PET surface were investigated by atomic force microscopy（AFM）images,which revealed a smooth surface morphology of the untreated sample whereas a high surface roughness for the plasma and/or alkaline treated *** effects of atmospheric pressure plasma on alkaline etching of the structure and properties of PET were investigated by means of differential scanning calorimetry（DSC）,the main objective of performing DSC was to investigate the effect of the plasma pre-treatment on the T_g and T_*** a tensile strength tester YG065 H and following a standard procedure the maximum force and elongation at maximum force of PET materials was *** and argon plasma pre-treatment was found to increase the PET fabric weight loss *** color strength of PET fabrics was increased by various plasma pre-treatment *** penetration of plasma and alkaline reactive species deep into the PET structure results in better dyeability and leaves a significant effect on the K/S values of the plasma pre-treated *** indicated that plasma pre-treatment has a great synergistic effect with the alkaline treatment of PET.

关键词： atmospheric pressure plasma synergistic effect alkaline treatment polyethylene terephthalate materials K/S value surface roughness

Wet spinning of PVA composite fibers with a large fraction of multi-walled carbon nanotubes

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Progress in Natural Science:materials International 2015年第5期25卷 445-452页

作者： Dengpan Lai Yizhe Wei Liming Zou Yongjing Xu Hongwei Lu state key laboratory for modification of chemical fibers and polymer materials College of Materials Science and Engineering Donghua University

PVA composites fibers with a large fraction of multi-walled carbon nanotubes modified by both covalent and non-covalent functionalization were produced by a wet-spinning *** XQ-1 tensile tester,thermogravimetric analysis,scanning electron microscopy,differential scanning calorimetry,and wide-angle X-ray diffraction were used to characterize the properties of PVA/MWNT composite *** TGA results suggested that MWNTs content in composite fibers were ranged from 5.3 wt%to 27.6 wt%.The mechanical properties of PVA/MWNT composite fibers were obviously superior to pure PVA *** Young's modulus of composite fibers enhanced with increasing the content of MWNTs,and it rised gradually from 6.7 GPa for the pure PVA fiber to 12.8 GPa for the composite fibers with 27.6 wt%***,the tensile strength increased gradually from 0.39 GPa for the pure PVA fiber to 0.74 GPa for the composite fibers with 14.4 wt%***,the tensile strength of the composite fibers decreased as the MWNTs content up to 27.6 wt%.SEM results indicated that the MWNTs homogeneously dispersed in the composite fibers,however some agglomerates also existed when the content of MWNTs reached27.6 wt%.DSC results proved strong interfacial interaction between MWNTs and PVA chain,which benefited composite fibers in the efficient *** characterization showed that the orientation of PVA molecules declined from 94.1%to 90.9%with the increasing of MWNTs *** good dispersibility of MWNTs throughout PVA matrix and efficient stress-transfer between MWNTs and PVA matrix may contributed to significant enhancement in the mechanical properties.

关键词： Multi-walled carbon nanotubes(MWNTs) Poly(vinyl alcohol)(PVA) Wet-spinning Composite fibers

fibers Make a Better Life

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Chinese Journal of polymer Science 2022年第4期40卷 331-332页

作者： Li-Ping Zhu Shu-Guang Yang Mei-Fang Zhu state key laboratory for modification of chemical fibers&polymer materials College of Materials Science&EngineeringDonghua UniversityShanghai 201620China

Naturally occurring fibers,such as cotton,flax,silk,and wool have been utilized by mankind for *** silk gauze gown of Han-dynasty found in 1972 by archaeological discovery in Mawangdui Han Tomb weighs only 49 *** demonstrates the advanced silkworm cultivation,harvesting and weaving techniques in the early Han Dynasty in *** today,we are not able to replicate this silk gown with such light *** a long time.

关键词： wool harvesting silk

Synthesis and Characterization of Easily Colored Meta-aramid Copolymer Containing Ether Bonds

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Chinese Journal of polymer Science 2019年第3期37卷 227-234页

作者： Na Li Xing-Ke Zhang Jun-Rong Yu Yan Wang Jing Zhu Zu-Ming Hu state key laboratory for modification of chemical fibers and polymer materials College of Materials Science and Engineering Donghua University

This work described the preparation of easily colored meta-aramid(PMIA) copolymers from m-phenylenediamine(MPD),isophthaloyl dichloride(IPC), and 3,4′-oxydianiline(3,4′-ODA) via solution polycondensation in N,N-dimethylacetamide(DMAc). The novel co-PMIAs were obtained in relatively high inherent viscosities ranging from 1.32 dL/g to 2.53 dL/g, which could be easily cast into flexible films with high transparence or spun into fibers. All the newly synthesized copolymers possessed excellent thermal stabilities even better than that of commercial PMIA, with 5% weight loss temperatures higher than 430 °C in nitrogen measured by TGA and glass transition temperature of 267–277 °C measured by DSC. The cast films exhibited good mechanical properties with a tensile strength up to107 MPa and a tensile modulus up to 2.2 GPa. The resultant PMIAs also showed good solubility and better dye ability for cationic dyes.

关键词： Copolymerized meta-aramid Solution polycondensation Dyeability

Role of humidity on the structures and properties of regenerated silk fibers

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Progress in Natural Science:materials International 2015年第5期25卷 430-436页

作者： Qingfa Peng Huili Shao Xuechao Hu Yaopeng Zhang state key laboratory for modification of chemical fibers and polymer materials College of Materials Science and Engineering Donghua University

Silk fiber was processed from highly concentrated spinning dope to solid fibers along with water removal. To understand the mechanism of water removal during silk fiber spinning process, a microfluidic chip was designed and applied to investigate the structures and mechanical properties of two kinds of regenerated silk fibroin fibers dry-spun at different relative humidity. The experimental results showed that the diameters of the fibers spun at 40% RH are always larger than the fibers spun at 50% RH due to different removal rates of water. The fibers spun at low humidity contain more β-sheet structure and lower degree of chain orientation and crystalline orientation. These results indicate that the fast phase transition of silk fibroin from sol–gel to silk fiber undergoes with rapid water removal and higher fiber orientation relates to more residue water and drawing force.

关键词： Dry spinning Relative humidity Biomimetic Regenerated silk fibroin Wide angle X-ray diffraction

Fabrication of 6FDA-HFBAPP Polyimide Asymmetric Hollow Fiber Membranes and Their CO2/CH4 Separation Properties

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Chinese Journal of polymer Science 2019年第8期37卷 815-826页

作者： Cong-Jun Gan Xiao-Chen Xu Xue-Wei Jiang Feng Gan Jie Dong Xin Zhao Qing-Hua Zhang state key laboratory for modification of chemical fibers and polymer materials College of Materials Science and Engineering Donghua University

In this work, poly(amide acid) solution, the precursor of polyimide, was synthesized by the reaction of 4,4′-(hexafluoroisopropylidene)diphthalicanhydride and 2,2-bis[4-(4-aminophenoxy)phenyl]-hexafluoropropanane in the solvent of N-methyl-2-pyrrolidone(NMP) and tetrahydrofuran(THF). Then, hollow fiber membranes for high flux gas separation were prepared by dry-jet wet spinning using the precursor solution of poly(amide acid) as the spinning dope and a subsequent imidization process. Silicone rubber was further coated outside the obtained hollow fiber membranes to repair the defects on the denser layer. The effects of internal, external coagulation bath ratios with air gap, and coating solution concentrations on the morphologies, structures, and separation performance of the membranes were studied. Results showed that the sponge-like support layer was formed when the content of NMP was increased from 50% to 90% in the internal coagulation bath. The outer surface of the membrane became denser when the water content in the external coagulation bath increased from 40% to 100%, and the separation coefficient of CO2/CH4 increased by 2 times. This value could reach up to 1.4 when the air gap was 6 cm. With tuning the mass fraction of silicone rubber as 5%, hollow fiber composite membranes with uniform coating layer and an improved separation coefficient of 5.4 could be obtained.

关键词： Polyimide Gas separation Preparation conditions Membrane structure Permeability

Coordination of thin-film nanofibrous composite dialysis membrane and reduced graphene oxide aerogel adsorbents for elimination of indoxyl sulfate

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Chinese Journal of chemical Engineering 2022年第9期35卷 111-121页

作者： Yuanyuan Jin Siping Ding Peiyun Li Xuefen Wang state key lab for modification of chemical fibers and polymer materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620China

The protein-bound uremic toxins,represented by indoxyl sulfate(IS),have been associated with the progression of chronic kidney disease and the development of cardiovascular disease in the presence of impaired renal ***,we proposed a novel strategy of thin-film nanofibrous composite(TNFC)dialysis membrane combined with reduced graphene oxide(rGO)aerogel adsorbents for clinical removal of IS as well as high retention of *** TFNC membrane was prepared by electrospinning in conjunction with coating-reaction method and proved to have good selectivity and *** further improve the removal rate of toxins,we used a medium hydrothermal method following by freeze-drying treatment to obtain the r GO aerogel *** exhibited excellent adsorption for IS with a maximum adsorption capacity of 69.40 mg·g^(-1)throughπ-πinteraction and hydrogen bonding interaction based on Langmuir isotherm ***-dependent absorption experiments showed that it reached adsorption equilibrium within 4 h,which was matched with the hemodialysis *** coordination was significantly exhibited by introducing r GO aerogel blocks into the dialysate for absorbing the diffused free IS during *** the advantages of the TFNC dialysis membrane and the rGO aerogel,the volume of dialysate for hemodialysis was only one-tenth of that without adsorbent blocks but with very comparable dialysis performance(the clearance of IS at 51.8%and the retention of HSA over 98%),which could lighten conventional hemodialysis effectively and be benefit to realize the miniaturization of the hemodialysis ***,the coordination of the TFNC dialysis membrane and rGO aerogel adsorbents would open a new path for the development of portable artificial kidney.

关键词： Indoxyl sulfate Thin-film nanofibrous composite membrane rGO aerogel adsorbents Hemodialysis Coordination Portable artificial kidney

Study on Drying Process of 3Al_2O_3·2SiO_2 Mullite Gel

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Journal of Donghua University(English Edition) 2008年第6期25卷 616-620页

作者：宋会锋康庄顾利霞 state key lab for modification of chemical fibers and polymer materials Donghua University

Monophasic mullite gel with composition 3Al2O3·2SiO2 was prepared by the sol-gel method using aluminium nitrate nonahydrate, aluminium-tri-isopropoxide, and tetraethylorthosili-cate as reagents. Gels with different drying control chemical additives(DCCAs) and polyvinylpyrrolidone(PVP) as spinning assistant were dried at several temperatures. The influences of temperature, DCCAs and PVP in the drying process were investigated. N,N-dimethylformamide(DMF) was the optimum DCCA at 70℃ in the drying process. PVP decreased the solvent volatilization speed and prevented gel crack to a certain extent. FTIR results revealed that free water, ethanol, and isopropanol were completely removed by the drying procedure.

关键词： sol-gel process DCCAs PVP crack-free

Effects of chromophore concentration and film thickness on thermo-optic properties of electro-optic fluorinated polyimide films

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Chinese Optics Letters 2007年第12期5卷 712-714页

作者：宋洪祥吴承训 state key laboratory for modification of chemical fibers and polymer materials Donghua UniversityShanghai 200051

Electro-optic （EO） effect and thermo-optic （TO） effect are jointly considered on the basis of field-induced and temperature-affected perturbations of the operating point in waveguide components. TO coefficients of EO fluorinated polyimide films with side-chain azobenzene chromophore were measured by attenuated- total-reflection （ATR） technique at different temperatures with TE- and TM-polarized lights, respectively. It is found that the absolute values of TO coefficients increase with the increments of both chromophore concentration and film thickness, but the polarization dependence of TO coefficients increases with the increment of chromophore concentration and decreases with the increment of film thickness.

关键词： Azobenzene Chromophores Electrooptical effects Film thickness Light reflection Polyimides polymer films Waveguide components