Novel electrically conductive and ferromagnetic composites of poly(aniline‐co‐aminonaphthalenesulfonic acid) with iron oxide nanoparticles: Synthesis and characterization

Nanocomposites of iron oxide (Fe₃O₄) with a sulfonated polyaniline, poly(aniline‐co‐aminonaphthalenesulfonic acid) [SPAN(ANSA)], were synthesized through chemical oxidative copolymerization of aniline and 5‐amino‐2‐naphthalenesulfonic acid/1‐amino‐5‐naphthalenesulfonic acid in the presence of Fe₃O₄ nanoparticles. The nanocomposites [Fe₃O₄/SPAN(ANSA)‐NCs] were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), X‐ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, elemental analysis, UV–visible spectroscopy, thermogravimetric analysis (TGA), superconductor quantum interference device (SQUID), and electrical conductivity measurements. The TEM images reveal that nanocrystalline Fe₃O₄ particles were homogeneously incorporated within the polymer matrix with the sizes in the range of 10–15 nm. XRD pattern reveals that pure Fe₃O₄ particles are having spinel structure, and nanocomposites are more crystalline in comparison to pristine polymers. Differential thermogravimetric (DTG) curves obtained through TGA informs that polymer chains in the composites have better thermal stability than that of the pristine copolymers. FTIR spectra provide information on the structure of the composites. The conductivity of the nanocomposites (～ 0.5 S cm^?1) is higher than that of pristine PANI (～ 10^?3 S cm^?1). The charge transport behavior of the composites is explained through temperature difference of conductivity. The temperature dependence of conductivity fits with the quasi‐1D variable range hopping (quasi‐1D VRH) model. SQUID analysis reveals that the composites show ferromagnetic behavior at room temperature. The maximum saturation magnetization of the composite is 9.7 emu g^?1. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007     

Sulfonated polyimide and poly (ethylene glycol) diacrylate based semi‐interpenetrating polymer network membranes for fuel cells

Semi‐interpenetrating polymer network (semi‐IPN) membranes based on novel sulfonated polyimide (SPI) and poly (ethylene glycol) diacrylate (PEGDA) have been prepared for the fuel cell applications. SPI was synthesized from 1,4,5,8‐naphthalenetetracarboxylic dianhydride, 4,4′‐diaminobiphenyl 2,2′‐disulfonic acid, and 2‐bis [4‐(4‐aminophenoxy) phenyl] hexafluoropropane. PEGDA was polymerized in the presence of SPI to synthesize semi‐IPN membranes of different ionic contents. These membranes were characterized by determining, ion exchange capacity, water uptake, water stability, proton conductivity, and thermal stability. The proton conductivity of the membranes increased with increasing PEGDA content in the order of 10^?1 S cm^?1 at 90°C. These interpenetrating network membranes showed higher water stability than the pure acid polyimide membrane. This study shows that semi‐IPN SPI membranes based on PEGDA which gives hydrophilic group and structural stability can be available candidates comparable to Nafion® 117 over 70°C. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

Preparation and characterization of sulfonated polyetherimide/polyetherimide blend membranes

Polyetherimide (PEI) was sulfonated by chlorosulfonic acid (CSA) in 1,2‐dichloroethane for the first time. With the increase of the CSA/PEI repeat unit ratio and/or reaction time, the ion‐exchange capacity (IEC) of the sulfonated polyetherimide (SPEI) increased accordingly. Water‐uptake testing and contact‐angle measurement showed that the hydrophilicity of the SPEI increases with the increase of the IEC. Membranes were fabricated from SPEI/PEI blends with different ratios. The morphologies of the blend membranes were examined by scanning electron microscopy, which showed that the membrane pore size is larger when SPEI with higher IEC was used. With the increase of SPEI ratio in the blend membranes, the membrane pore size also increased. The contact‐angle data of the membranes showed that the hydrophilicity of the blend membrane was elevated because of the sulfonate group on the SPEI molecular backbone. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1709–1715, 2004     

磺化聚醚砜的制备与表征

针对聚醚砜亲水性差的问题,以氯磺酸为磺化剂对聚醚砜进行磺化,制得不同磺化度的磺化聚醚砜及磺化聚醚砜分离膜.采用傅立叶变换红外光谱(FTIR)、差示扫描量热(DSC)和热重分析(TGA)对磺化聚醚砜进行了表征,并对分离膜水通量进行了测定.结果表明:随着磺化度的提高,磺化聚醚砜的玻璃化转变温度提高;在质子性极性溶剂中的溶解性增加,在非质子极性溶剂中的溶解性降低;亲水性提高,分离膜的水通量随之增加.     

气电纺制备新型纳米材料及骨细胞相容性研究

探索纳米羟基磷灰石（n—HA）与聚醚砜（PES）电纺的最佳比例，制备新型纳米材料，并探讨其骨细胞相容性。分别以n-HA／PES：20／80，15／85，10／90（质量分数，下同），PES22％为电纺的比例，用N，N．二甲基甲酰胺（DMF）作溶剂，通过气电幼的方法制备了纳米羟基磷灰石与聚醚砜的复合纳米材料，运用扫描电镜、X射线能谱分析等方法进行检测，并在制得的纳米材料上接种成骨细胞，发现当n—HA与PES比例为10／90时，纺丝效果较好，纤维分布均匀；接种成骨细胞后，与阴性对照组比较，细胞在增殖上具有优势。从而证明气电纺制备的n—HA／PES纳米材料具有良好的骨细胞相容性。     

油井水泥降失水剂SPS的制备和性能研究

通过磺化改性,制备了磺化聚苯乙烯(SPS)作为油井水泥降失水剂.研究了反应条件对SPS磺化度的影响、SPS的磺化度与失水控制的关系、SPS水泥浆体系的性能.实验结果表明:在相同的条件下,磺化度越高,失水控制越好;在最佳条件下制备的SPS具有良好的降失水性能,SPS的水泥浆体系具有良好的流变性能和较好的耐温性能;在120℃下,其水泥浆体系的稠化时间,用常用的缓凝剂可调整到337 min,SPS对水泥浆其他性能无不良影响.     

Preparation of Hemodialyzer Made from Polyethersulfone Membrane by Dual-bath Coagulation Method

The dual-bath coagulation method was used for the preparation of PES membrane in this experiment. The main intent of this stndy was to assess the efforts of gelation conditions on the structures and properties. The dense top layer as well as porous supporting layer can be made by duel-bath coagulation method simultaneous- ly. Different internal quench medium obtained different membrane with different structures. With the increase in time in the first coagulation bath, pure water flux decreased and the clearance rates of urea and creatinine both first increased then decreased and increased slightly in the end. With the temperature of the second coagtdation bath increasing, pure water flux increases and the clearance rates of urea and creatinine first increases then de- creases and increases a little at last. Higher DMSO concentration （wt/wt） in the second coagulation bath results in the increase of pure water flux and the decrease of urea ＆ creatinine clearance rates.     

蒸发时间对两级凝胶法制备的聚醚砜膜结构和性能的影响

主要探讨了蒸发时间对用两级凝胶法(dual—bath coagulation method)所制得的聚醚砜(PES)超滤膜的性能和结构的影响．结果表明，随着蒸发时间的延长，水通量先减小后增大；肌肝和尿素去除率均是先升高而后降低，然后再升高的趋势；膜的孔隙率上升，平均孔径下降．在蒸发时间为10s时，肌肝和尿素去除率最高，且水通量适中，是血液净化用聚醚砜膜的最佳成形条件．