聚间苯硫醚和聚对苯硫醚的对比表征

聚对苯硫醚[poly(pphenylenesulfide),简称pPPS]的分子链是由对苯撑基和硫原子交替连接构成而使制品抗冲击能力差[1](有些研究者用共聚或共混的方法在pPPS中引入间位结构来达到减少其结晶度,增强韧性的目的)。余自力等[2]用硫磺溶液法合成了mPPS、pPPS及其共聚物,认为在pP...     

纳米花状MnO_2/PPS功能复合滤料的制备及其NH_3-SCR脱硝性能研究

首先采用表面活性剂十二烷基硫酸钠(SDS)对聚苯硫醚(PPS)滤料进行表面活化,由于SDS亲水基团(SO_4~–)与溶液中的H~+发生静电吸附作用,使得之后高锰酸钾在PPS滤料表面原位生成纳米花状二氧化锰,制得nf-MnO_2/PPS复合滤料;并通过探讨高锰酸钾与滤料的质量比、反应时间对nf-MnO_2/PPS复合滤料结构及性能的影响,从而得到最佳制备条件.并利用场发扫描电子显微镜(FESEM)、透射电子显微镜(TEM)、X-射线光电子能谱(XPS)、脱硝活性测试等分析手段对该复合滤料的结构和性能进行了研究;在其基础上利用原位聚合法,在复合滤料表面形成聚吡咯包覆层,制得nf-MnO_2/PPy@PPS复合滤料,并通过多种测试分析手段对改性滤料的结构和性能进行了研究.最后,脱硝测试结果显示,由最佳条件制备出的nf-MnO_2/PPS表现出了最优异的脱硝活性,其在80~180℃时的NO转化率达到36%~100%,nf-MnO_2/PPy@PPS表现出了更好的结合强度和催化稳定性能,但脱硝活性有所下降.     

Effect of sizing materials of carbon fiber on solid-state cure of poly(p-phenylene sulfide)

The effect of sized carbon fibers on the solid-state cure of poly(p-phenylene sulfide) (PPS) was studied using differential scanning calorimetry. PPS resin reinforced with sized carbon fiber exhibited the largest cure peak for all cure temperatures and showed a second peak at low cure temperature which was absent in both PPS reinforced with desized carbon fiber and neat PPS resin. In a separate experiment in which epoxy prepolymer/PPS mixture was cured, the exothermic reaction was related to the presence of the epoxy sizing used on the carbon fiber. © 1998 John Wiley & Sons, Ltd.     

STUDIES ON REGULARITY OF POLY PHENYLSILSESQUIOXANE CHAINS

IR and ~(29)Si NMR were used to determine the structures of ladderlike polymer polyphenylsilsesquioxanes (PPS). It was found that PPS with lots of defects had a wide and strong absorption band in 1000—1400 cm~(-1) with only one sharp peak at 1137 cm~(-1) while two peaks (1130 and 1045 cm~(-1) were observed for PPS with perfect ladderlike structure. Branching and crosslinking of PPS lead to the reduction of 1045 cm~(-1) peak. ~(29)Si NMR spectra, however, showed two peaks (δ=-78 ppm and -87 ppm when δ_(HMDS)=0 ppm) for defective or branched PPS. The -87 ppm peak is related to the ladderlikely constructed Si atoms and -78 ppm corresponds to defective Si atoms. PPS with defects less than 0.1% chain units was obtained by azeotropic polycondensations.     

Silane surface modification of boron nitride for high thermal conductivity with polyphenylene sulfide via melt mixing method

Polyphenylene sulfide (PPS) is a promising engineering polymer, which is used for various industrial applications. In this study, we developed a highly thermally conductive PPS composite containing boron nitride (BN) as a thermally conductive ceramic filler. (3‐Aminopropyl) triethoxysilane was doped onto the surface of hydroxyl‐functionalized BN using a simple sol–gel process. The modified BN particles were embedded in a PPS matrix via a melt mixing process using a twin extruder to form BN‐Si composites. The maximum thermal conductivity 3.09 W/m·K was exhibited by the surface‐modified BN‐Si containing 60 wt%. This value was 116% higher than the thermal conductivities of the pristine BN and PPS matrix, respectively. The surface‐treated composites also showed an improved storage modulus because of an improvement in the interfacial adhesion and interaction between the BN filler and the PPS matrix. Copyright © 2017 John Wiley & Sons, Ltd.     

Polyphenylene sulfide‐based adsorption resins: synthesis,characterization and adsorption performance for Hg(II) and As(V)

A series of novel adsorption resins were synthesized via the chloromethylation of polyphenylene sulfide (PPS) resin and subsequent functional group conversion reaction. Their chemical structure, thermal stability, and morphology were systematically characterized by the Fourier transform infrared spectroscopy, elemental analysis, Raman spectroscopy, thermogravimetric analysis, scanning electron microscope, and energy dispersive spectrometer, respectively. The experimental results showed that the thioureido, mercapto, aminopyridine, and quaternary ammonium groups had been respectively introduced into PPS matrix, the functional group content of PPS‐based mercapto resin (HS‐PPS), aminopyridine resin (AP‐PPS), and quaternary ammonium resin (QA‐PPS) were about 2.20, 1.71, and 2.61 mmol g^?1, respectively. The adsorptive performance for Hg (II) and As (V) were studied by batch adsorptive method; the adsorption capacities of the HS‐PPS and AP‐PPS resin for Hg (II) were 210.65 and 169.06 mg g^?1. The adsorption capacity of the QA‐PPS resin was 88 mg g^?1 for As (V). Copyright © 2017 John Wiley & Sons, Ltd.     

Thermal and dynamic mechanical properties of PES/PPS blends

Blends of poly(ether-sulfone) (PES) and poly(phenylene sulfide) (PPS) with various compositions were prepared using an internal mixer at 290°C and 50 rpm for 10 min. The thermal and dynamic mechanical properties of PES/PPS blends have been investigated by means of DSC and DMA. The blends showed two glass transition temperatures corresponding to PPS-rich and PES-rich phases. Both of them decreased obviously for the blends with PES matrix. On the other hand, T_g of PPS and PES phase decreased a little when PPS is the continuous phase. In the blends quenched from molten state the cold crystallization temperature of PPS was detected in the blends of PES/PPS with mass ratio 50/50 and 60/40. The melting point, crystallization temperature and the crystallinity of blended PPS were nearly unaffected when the mass ratio of PES was less than 60%, however, when the amount of PES is over 60% in the blends, the crystallization of PPS chains was hindered. The thermal and the dynamic mechanical properties of the PPS/PES blends were mainly controlled by the continued phase. This revised version was published online in August 2006 with corrections to the Cover Date.     

聚苯硫醚的动态力学行为研究

本工作借助TBA技术研究了聚苯硫醚(PPS)的动态力学行为。结果表明,PPS的端基和分子量,热处理方式(固相处理或熔融处理)和处理时间,试样的热历史(淬火或退火)及制辫子所用的纤维的表面性质(玻璃纤维、碳纤维和石墨纤维及其表面处理)等因素对其动态力学行为均有影响。这些动态力学行为特征的变化与这些因素所引起的PPS的分子结构和超分子结构的变化有关。     

聚苯硫醚副产物浆料的分离及氯化锂的回收研究

聚苯硫醚(PPS)的工业合成采用对二氯苯和硫化钠为原料,N-甲基-2-吡咯烷酮(NMP)为溶剂,氯化锂为助剂,经加压缩聚反应而成.该反应除了获得PPS外,还产生一部分副产物淤浆,有必要对其组成物进行分离回收和资源化利用.本文采用四氢呋喃(THF)为添加剂对这种副产物淤浆进行了分离研究,并对其中的锂盐进行了回收研究.结果表明,采用THF添加剂可以较为容易地将浆料分离为PPS低聚物、NMP以及无机盐,采用有机溶剂提取法可以回收氯化锂,LiCl的回收率可达40%.     

热致相分离法制备聚苯硫醚微孔膜

采用热致相分离法,以己内酰胺为溶剂,制备得到了聚苯硫醚微孔膜并对薄膜性能表征.聚苯硫醚-己内酰胺体系制膜的优点之一是溶剂己内酰胺是水溶性的,可以采用纯水作为后处理的萃取剂.选择了合适的浓度,利用压制成型法制备聚苯硫醚平板膜;研究了体系冷却时的相行为,并考察了降温速率、聚合物浓度等因素对微孔形态与薄膜性能的影响.研究表明,聚苯硫醚-己内酰胺体系以固液分相为主,萃取后形成球晶状的微孔结构.降温速率对薄膜的微孔形态、孔径以及连通性有重要影响;当体系以较低降温速率冷却时,多孔形态为枝叶状,形成了更多的开孔结构并获得了更大的孔径,这是获得高通量微孔膜的主要原因.通过控制降温速率可以制备纯水通量大于100 L/m2h,孔径约4～5μm且连通性良好的聚苯硫醚微孔膜;研究了聚合物浓度的影响,薄膜的纯水通量随着聚合物浓度的增大而减小,并且当聚苯硫醚浓度>50 wt%时,由于大于临界浓度而失去渗透性.     

碳纳米管改性聚苯硫醚熔纺纤维的结构与性能研究

将多壁碳纳米管(MWCNTs)和聚苯硫醚(PPS)经过熔融挤出后制备成复合材料切片,并采用熔融纺丝法制得碳纳米管改性聚苯硫醚复合纤维.采用扫描电镜(SEM)、拉曼光谱、示差扫描量热分析(DSC)、动态机械分析(DMA)以及力学性能测试等表征手段研究了复合纤维中碳管的分散状态,与基体的界面作用,复合纤维的结晶性能以及力学性能,从而探讨了聚苯硫醚/碳纳米管复合纤维体系的微观结构与宏观性能之间的关系.研究表明,聚苯硫醚分子结构与碳纳米管之间具有的π-π共轭作用使碳管较为均匀的分散在基体中,界面结合较为紧密.同时熔融纺丝过程中的拉伸作用使碳管进一步解缠并使碳管沿纤维拉伸方向取向.另一方面,拉曼光谱显示拉伸作用有效地增强了界面作用,有利于外界应力的传递.碳管的良好分散以及强的界面作用使复合纤维力学性能得到大幅度的提高,当碳管含量达到5 wt%时,复合纤维的模量有了明显的提高,拉伸强度较纯PPS纤维提高了近220%.     

Interaction of albumins and heparinoids investigated by affinity capillary electrophoresis and free flow electrophoresis

A fast and precise affinity capillary electrophoresis (ACE) method has been applied to investigate the interactions between two serum albumins (HSA and BSA) and heparinoids. Furthermore, different free flow electrophoresis methods were developed to separate the species which appears owing to interaction of albumins with pentosan polysulfate sodium (PPS) under different experimental conditions. For ACE experiments, the normalized mobility ratios (∆R/R_f), which provided information about the binding strength and the overall charge of the protein‐ligand complex, were used to evaluate the binding affinities. ACE experiments were performed at two different temperatures (23 and 37°C). Both BSA and HSA interact more strongly with PPS than with unfractionated and low molecular weight heparins. For PPS, the interactions can already be observed at low mg/L concentrations (3 mg/L), and saturation is already obtained at approximately 20 mg/L. Unfractionated heparin showed almost no interactions with BSA at 23°C, but weak interactions at 37°C at higher heparin concentrations. The additional signals also appeared at higher concentrations at 37°C. Nevertheless, in most cases the binding data were similar at both temperatures. Furthermore, HSA showed a characteristic splitting in two peaks especially after interacting with PPS, which is probably attributable to the formation of two species or conformational change of HSA after interacting with PPS. The free flow electrophoresis methods have confirmed and completed the ACE experiments.     

Isothermal crystallization kinetics,morphology, and thermal conductivity of graphene nanoplatelets/polyphenylene sulfide composites

Graphene nanoplatelets (GNP) and polyphenylene sulfide (PPS) were used as filler and matrix, respectively, to produce composites. The PPS/GNP thermal composites were prepared via a melt blending method. The effects of GNP on crystallization behavior and kinetics, morphology, and thermal properties of PPS/GNP composites were investigated. To determine the isothermal crystallization kinetics parameters and isothermal crystallization activation energy, the Avrami model was used to comparatively analyze the relevant DSC experimental data. The results show that GNP provides an obvious heterogeneous nucleation effect on PPS to accelerate the crystallization and decrease isothermal crystallization activation energy. Thermal conductivity values of PPS/GNP composites with various GNP contents revealed that GNP remarkably increases thermal conductivity of composites mainly via a layered dispersion in PPS matrix. Thermal conductivity also increased with increasing GNP content, which was further improved at elevated temperatures. The thermal conductivities of PPS composite containing 30 mass% of GNP were 1.156 and 1.350 W m^?1 K^?1 at 30 and 110 °C, respectively, indicating an increase of more than 3 times compared with the neat PPS.     

Preparation and characterization of polyphenylene sulfide–based chelating resin–functionalized 2‐amino‐1,3,4‐thiadiazole for selective removal Hg(II) from aqueous solutions

A novel chelating resin (PPS‐ATD) containing N and S elements was prepared through the chloromethylation of polyphenylene sulfide resin and subsequent functionalization with 2‐amino‐1,3,4‐thiadiazole (ATD). The structure of PPS‐ATD was systematically characterized and analyzed by the Fourier transform infrared spectroscopy, elemental analysis, thermogravimetric analysis, scanning electron microscope, and energy dispersive spectrometer. The adsorption performance of PPS‐ATD was evaluated by batch methods at different pH, temperature, adsorption time, and initial concentration, and the results showed that the PPS‐ATD exhibited high adsorption capacity (197.79 mg·g⁻¹ at 298 K) and selectivity for Hg(II). The adsorption of PPS‐ATD for Hg(II) was well fitted by the Langmuir isotherm model, and the adsorption process was endothermic. After 5 consecutive regeneration cycles, no obvious loss in the adsorption capacity of the PPS‐ATD was found, which implied that the PPS‐ATD had great application prospects in the treatment of mercury‐containing wastewater.     

Characterization of self-assembled monolayers of porphyrins bearing multiple-thiol and photoelectric response

Self-assembled monolayers(SAMs) of thiol-derivatized porphyrin molecules on Au substrate have attracted extensively interest for use in sensing,optoelectronic devices and molecular electronics.In this paper,tetra-[p-(3-mercaptopropyloxy)-phenyl]porphyrin was synthesized and self-assembled with thiol on Au substrate for porphyrin SAMs(PPS 4).The electrochemical results demonstrated that PPS 4 could form excellent SAMs on gold surface.Self-assembled nanojunctions of PPS 4 were fabricated by using gold nanogap electrodes(gap width:ca.100 nm).With the light on/off,the nanojunctions showed current high/low as nanometer scaled photo switch.     

热致相分离法制备聚苯硫醚多孔膜I．聚苯硫醚和二苯酮体系

研究了聚苯硫醚／二苯酮体系的热力学相图，探讨了热致相分离法制备耐高温、耐溶剂的聚苯硫醚多孔膜的可能性，并就聚苯硫醚与二苯酮的组成比以及降温速率对多孔结构形成的影响规律进行了讨论。     

Phase separation in semicrystalline blends of poly(phenylene sulfide) and poly(ethylene terephthalate). II. Effect of poly(phenylene sulfide) homopolymer solubilization of PPS‐graft‐PET copolymer on morphology and crystallization behavior

The morphology and crystallization behavior of poly(phenylene sulfide) (PPS) and poly(ethylene terephthalate) (PET) blends compatibilized with graft copolymers were investigated. PPS‐blend‐PET compositions were prepared in which the viscosity of the PPS phase was varied to assess the morphological implications. The dispersed‐phase particle size was influenced by the combined effects of the ratio of dispersed‐phase viscosity to continuous‐phase viscosity and reduced interfacial tension due to the addition of PPS‐graft‐PET copolymers to the blends. In the absence of graft copolymer, the finest dispersion of PET in a continuous phase of PPS was achieved when the viscosity ratio between blend components was nearly equal. As expected, PET particle sizes increased as the viscosity ratio diverged from unity. When graft copolymers were added to the blends, fine dispersions of PET were achieved despite large differences in the viscosities of PPS and PET homopolymers. The interfacial activity of the PPS‐graft‐PET copolymer appeared to be related to the molecular weight ratio of the PPS homopolymer to the PPS segment of the graft copolymer (M_H/M_A). With increasing solubilization of the PPS graft copolymer segment by the PPS homopolymer, the particle size of the PET dispersed phase decreased. In crystallization studies, the presence of the PPS phase increased the crystallization temperature of PET. The magnitude of the increase in the PET crystallization temperature coincided with the viscosity ratio and extent of the PPS homopolymer solubilization in the graft copolymer. © 2000 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 38: 599–610, 2000     

热致相分离法制备聚苯硫醚多孔膜Ⅱ.聚苯硫醚和二苯砜体系

研究了聚苯硫醚/二苯砜体系的热力学相图,探讨了热致相分离法制备耐高温、耐溶剂的聚苯硫醚多孔膜的可能性,并就聚苯硫醚与二苯砜的组成比以及降温速率对多孔结构形成的影响规律进行了讨论。     

Reactive Blends of Poly(phenylene sulfide)/Hyperbranched Poly(phenylene sulfide)

Summary: Polymer blends consisting of linear poly(phenylene sulfide) (PPS) and hyperbranched PPS (HPPS) were obtained in melt. The solid-state properties of PPS and their blends were investigated by scanning electron microscopy (SEM), thermogravimetric analyzer (TGA), extraction measurement, differential scanning calorimetry (DSC) and dynamical mechanical analysis (DMA). Blends prepared by melt mixing turned out to be reactive as shown by the TGA and extraction measurement. SEM indicated that no phase separation occurs in PPS/HPPS blends. The degree of crystallization of the blends decreased with increasing HPPS content. Both the storage modulus and loss modulus increased as HPPS content increasing.     

Effects of solvent treatment on crystallization kinetics of poly(p-phenylene sulfide)

Isothermal melt crystallization kinetics were investigated by differential scanning calorimetry (DSC) for virgin and α-chloronaphthalene solvent-treated poly(phenylene sulfide) (PPS) systems. The overall crystallization rates were found to be much faster for the solvent-treated PPS than for the virgin neat PPS. Additionally, the Avrami crystallization plot for the solvent-treated PPS samples appeared as two straight portions with an apparent discontinuity, but as a continuous straight line for the virgin PPS system. After the treatment of solvent dissolution and subsequent drying, the residual trace α-chloronaphthalene, upon being quenched to the crystallization temperatures, initiated some localized solvent-induced nuclei-like crystals in PPS. It was the nuclei that enhanced secondary crystallization in treated PPS during the second stage, and the higher extents of secondary crystallization in the solvent-treated PPS caused the apparent discontinuous break in the Avrami plots. The causes for the difference were explained and the mechanism of the sequential primary/secondary crystallization kinetics for the solvent-treated PPS was satisfactorily described with a proposed series-parallel crystallization model. ©1995 John Wiley & Sons, Inc.