Polyphenylene Sulfide Research Articles

Mechanism of improvement in the strength of para-aramid paper by polyphenylene sulfide pulp

Aramid paper has been widely applied in aerospace, rail transit, and other fields because of its outstanding mechanical properties, high-temperature resistance, and excellent insulation. We prepared para-aramid chopped fibers/polyphenylene sulfide (ACFs/PPS) composite paper, which has superior mechanical strength compared with other aramid papers. However, the mechanism of PPS pulp improving para-aramid paper is still unclear. Herein, the structure change and interface behavior of composite paper during hot pressing were studied. The surface of ACFs was modified by PPS pulp in-situ melting and self-wetting at high temperatures, which made the surface of ACFs rough and viscous. ACFs were staggered in three-dimensional space, and countless network nodes were formed at the staggered parts. With the node as the vertex and the ACF as the side length, countless stable triangular structures were formed. Under this structure, the tensile fracture surface of the composite paper showed the splitting of the bulk structure of aramid fiber, indicating that the paper had strong interfacial strength. More importantly, PPS pulp breaks the limitation of weak interfacial strength between ACFs and resin matrix. We can predict that PPS pulp can be made into advanced paper-based materials with other high-performance inert fibers.

Preparation, Crystallization Behavior, Simultaneous Spectroscopic and Rheological Characterization of Polyphenylene Sulfide/Graphene Quantum Dots Nanocomposites

AbstractGraphene quantum dots are prepared conveniently and quickly with brown‐black humic acid as raw material by green oxidation process. The average size of GQDs is about 12 nm with a lattice spacing of 0.26 nm and GQDs have hydroxyl and carboxyl functional groups on their surface. Moreover, photoluminescence testing shows that GQDs have excellent photoluminescence properties with maximum excitation/emission wavelength at 347/478 nm. Next, polyphenylene sulfide (PPS)/GQDs nanocomposites are prepared by melt blending with GQDs and PPS. Mechanical tests show that the tensile strength and the impact strength of PPS can be greatly improved when the amount of GQDs is 0.5 wt% and tensile strength and the impact strength are increased by 53.38% and 375%, respectively. The nonisothermal crystallization of PPS/GQDs nanocomposites is investigated by differential scanning calorimetry, which shows that GQDs effectively increase the crystallization rate of PPS. The crystallization of PPS/GQDs nanocomposites during cooling are studied by Rheonaut technology analysis. The rheological results show that the storage modulus of PPS/GQDs (0.5 wt%) nanocomposites is increased by about 1.04 times than that of pure PPS, and 2D IR spectrum confirms that GQDs accelerate crystallization of PPS. Rheological studies present that GQDs have good compatibility with PPS.

Role of Agent Molecules for Low-Temperature Activation of Lithium-Ion Transport for Solid-State Polymer Electrolytes

The realization of all-solid-state lithium-ion batteries (LIBs) is often considered as the final challenge in the development of LIBs. Replacing Li-ion conductive liquid electrolytes with high-performance solid-state electrolytes is indispensable for the development of all-solid-state LIBs. Solid-state electrolytes under development fall into three classes: polymers, oxides, and sulfides. Polymer-based electrolytes have advantages over oxides and sulfides, such as formation of low-resistance electrolyte/electrode interfaces, good processability, and high energy-density owing to low density. Therefore, polymer-based solid-state electrolytes are being developed in both industry and academia as a practical route for realizing high-capacity LIBs.[1]For application in commercial LIBs, the electrolyte should have an ionic conductivity higher than 10-4 S/cm at room temperature. Conventional solid polymer electrolytes, such as polyethylene oxide (PEO)-based electrolytes, do not meet the performance requirements due to insufficient ionic conductivity in the range of 10-6 to 10-5 S/cm. Recently, polyphenylene sulfide (PPS)-based polymer electrolytes have been reported to yield ion conductivities as high as those of liquid electrolytes over a wide temperature range (> 1.0 × 10-4 S/cm at 25 °C, > 1.0 × 10-3 S/cm at 80 °C, and > 1.0 × 10-3 S/cm at −40 °C).[2] These electrolytes consist of base polymer chains containing PPS, Li salts that can dissociate into cations and anions, and neutral agent molecules. However, the detailed Li-ion transport mechanism in terms of the respective roles of the molecular components of PPS electrolytes is yet to be determined. This limited understanding hinders the further improvement of PPS-based electrolytes.In this study, we perform a series of first-principle calculations and demonstrate that certain types of neutral molecules (so-called agent molecules) accelerate solid-state lithium-ion migration when mixed with lithium salts.[3] We find that the intermolecular interaction in a selected agent-molecule/lithium-salt binary system is governed by the strong coupling between lithium and oxygen atoms. Upon the addition of agent molecules, the anionic species surrounding the lithium of lithium salts is replaced by the agent molecules. The resulting weakened Coulomb energy coupling between lithium and oxygen atoms is determined to be a key factor in enabling fast lithium-ion migration via facile dissociation of lithium salts and subsequent formation of ion-hopping sites in the form of lithium-free oxygen-cages. The structure-based interpretation of agent molecules suggests that neutral molecules with functional groups which enhance chemical resonance can be selected as potential agent molecules. We believe that the results obtained in this study serve as a theoretical basis for the future development of solid-state polymer electrolytes, particularly toward mitigating the dependence of lithium-ion transport on the movement of polymer chains.

On the R-curve behaviour of carbon/epoxy laminates with core-shell rubber nanoparticle and micro-fibre veil hybrid toughening: Carbon vs PPS veils

This paper investigates the effect of non-hybrid and hybrid toughening, via core-shell rubber (CSR) nanoparticles and non-woven micro-fibre veils, on the delamination resistance and crack migration in carbon fibre/epoxy laminates under mode-I and mode-II conditions—with an emphasis on the effect of veil fibre properties on toughening mechanisms and fracture energies. Core-shell rubber particles, varying in size from 100 nm to 3 μm, with 0–10 wt% content, are dispersed within the epoxy resin. Two non-woven veils with contrasting fibre properties (i.e. one with ∼6 mm (50 wt%) and ∼12 mm (50 wt%) short carbon fibres and another with ∼6 mm short polyphenylene sulfide (PPS) fibres) with 10 g/m2 areal weights are used to introduce hybrid toughening at the interlaminar region. Carbon fibre/epoxy laminates with five different toughening routes (i.e. CSR toughening, carbon veil toughening, PPS veil toughening, carbon veil and CSR hybrid toughening, and PPS veil and CSR hybrid toughening) are manufactured with a two-part resin using vacuum infusion and out-of-autoclave curing. Double cantilever beam (DCB) and four-point end-notch-flexure (4-ENF) specimens are tested for mode-I and mode-II fracture energies and R-curves. Fracture surfaces are investigated to characterise crack migration and energy dissipation mechanisms. The results indicate that mode-I and mode-II fracture energies are significantly enhanced (e.g. ∼275% in initiation and propagation under mode-I) with the combined core-shell rubber nanoparticle and veil toughening investigated—significantly altering micro-failure mechanisms, crack paths and R-curves. It is shown that the low modulus PPS fibre veils together with CSR particles provide stable crack growth, while high modulus carbon fibre veils with CSR particles lead to unstable crack growth.

FEM numerical simulation of contact stresses between driving shaft and hub impeller of fuel pump

The aim of the work was to test the contact stresses in the model system of the turbine hub cooperating with the fuel pump drive shaft. The hypothesis of the work was that, by means of FEA, it is possible to assess the contact stresses in the materials of the turbine hub and the fuel pump shaft during torque transmission. A turbine with fibre-reinforced polyphenylene sulphide (PPS) composite cooperating with a stainless steel shaft (X46Cr13/1.4034) in a commonly used D-flat shape joint was selected for the experimental research. To assess contact stresses, the CAD model (NX, Siemens) of the entire turbine was limited to the hub area. The drive shaft is supported in accordance with the bearing in the fuel pump, and the possibility of rotation about the axis along the length of the torque-producing magnet is taken away. The system was loaded with a torque of 200 Nmm on the turbine. The turbine hub and shaft were calculated, taking into account the phenomenon of contact detachment or slip at the value of the friction coefficient of 0.1. The pressure transmission area was found in the area at the edge of the flat surface D-flat and on the opposite side of the D-convexity. The contact stresses on the D-flat side reached values close to the composite strength. The studies did not take into account the technological inaccuracies, thermal deformation, local material properties, and wear. The value of the friction coefficient was not measured in realistic conditions with fuel lubrication. FEA has been achieved, which allows to reduce the cost of experimental research. The proposed model allows for further studies of the influence of elasticity of various materials and structures on contact stresses in order to assess wear resistance.

Development of the Polyphenylene Sulfide Synthesis Technology

Development of the Polyphenylene Sulfide Synthesis Technology

Thermal stability of anisotropic bonded magnets prepared by additive manufacturing

AbstractIn this research, anisotropic NdFeB + SmFeN hybrid and NdFeB bonded magnets are additively printed in a polyphenylene sulfide (PPS) polymer binder. Printed NdFeB + SmFeN PPS bonded magnets displayed excellent magnetic properties (Br[remanence] = 6.9 kG [0.69 T],Hcj[coercivity] = 8.3 kOe [660 kA/m], andBHmax[energy product] = 9.9 MGOe [79 kJ/m3]) with superior corrosion resistance and thermal stability. The anisotropic NdFeB bonded magnet shows a high coercivity of 14.6 kOe (1162 kA/m) with aBHmaxof 8.7 MGOe (69 kJ/m3). The coercivity and remanence temperature coefficients for NdFeB + SmFeN hybrid bonded magnets are −0.10%/K and −0.46%/K, and for NdFeB bonded magnets are −0.14%/K and −0.53%/K in the range of 300–400 K, indicating that the hybrid bonded magnets are thermally stable. The average flux aging loss for hybrid magnets was also determined to be very stable over 2000 h at 448 K (175°C) in air with 2.04% compared to that of NdFeB magnets with 3.62%.

Experimental Research on Dynamic Filtering Characteristics of Filter Materials for Electrostatic-Fabric Integrated Precipitator

In recent years, the electrostatic-fabric integrated precipitator has been widely used, and the dust filtration performance of the core component filter bag is the most important factor affecting its dust removal efficiency. In this work, the dynamic dust removal performance of different types of filter media and different experimental conditions were studied on the filter media filtration performance test platform. The experimental study of the filtration performance of different types of filter media showed that the filtration performance stability of polyphenylene sulfide (PPS) filter media was better than that of polyimide (PI) and polytetrafluoroethylene (PTFE) filter media. Increasing the mass per unit area of the filter media had obvious advantages in the short term, and the impregnation process was beneficial to the filter performance of the filter media. Membrane-coated filter media had the best filtration performance, gradient filter media filtration performance was the second, followed by conventional filter media, ordinary blended, and ultrafine blended filter media. Studies with different experimental conditions found that the filtration efficiency increased with increasing resistance, was not significantly affected by changes in inlet dust concentration, but decreased with the increasing filtering velocity. This experimental results provided an important basis for the selection of filter bags for the electrostatic-fabric integrated precipitator project.

Effect of Humidity on Metallizing on Polyphenylene Sulfide (PPS) with Atmospheric UV Treatment

Polyphenylene sulfide (PPS) is an engineering plastic; when reinforced with fillers, it exhibits high heat resistance, strength, and molding/dimensional stability. Plating on PPS without using harmful chemicals can meet the following requirements due to its excellent properties: low environmental load process, lightweight metal substitute materials, electromagnetic wave shielding materials, etc. This study focused on metallizing by atmospheric ultraviolet (UV) treatment of PPS. This process is generally used for the pretreatment of painting and adhesion, and it entails a small environmental load; however, the UV treatment of moist air produces various chemical species. Therefore, the humidity effect during metallizing via atmospheric UV treatment was investigated, revealing its influence on the adhesion strength of the resulting metal film. In a dry environment, a metal film with strong adhesion can be formed on PPS, and UV treatment under such conditions can maintain the structure of the PPS surface. In contrast, a weak layer was generated under wet conditions, reducing the adhesion strength between the metal film and PPS.

Simple preparation of ZIF-8 modified polyphenylene sulfide melt-blown film material and its organic dye removal performance

Simple preparation of ZIF-8 modified polyphenylene sulfide melt-blown film material and its organic dye removal performance

On mode-I and mode-II interlaminar crack migration and R-curves in carbon/epoxy laminates with hybrid toughening via core-shell rubber particles and thermoplastic micro-fibre veils

This study investigates the influence of hybrid toughening—via core-shell rubber (CSR) particles and non-woven thermoplastic veils—on the delamination resistance, crack migration and R-curve behaviour in carbon fibre/epoxy laminates under mode-I and mode-II conditions. Core-shell rubber particles, varying in size from 100 nm to 3 μm, with 0–10 wt% content, are dispersed within the epoxy resin, and thermoplastic micro-fibre veils with polyphenylene sulfide (PPS) fibres, with 5–20 g/m 2 areal weight, are introduced at the interlaminar region to achieve hybrid toughening. Carbon fibre/epoxy laminates are manufactured with a two-part resin using vacuum infusion and out-of-autoclave curing. Double cantilever beam (DCB) and four-point end-notch-flexure (4ENF) specimens are used to obtain mode-I and mode-II fracture energies and R-curves. Damage mechanisms and crack paths are characterised using fractography that provide understanding of energy dissipation. The results show that the hybrid toughening significantly improves fracture initiation and propagation energies ( i.e . mode I initiation by ∼245% and propagation by ∼275%, and mode-II initiation by ∼64% and propagation ∼215%) by extrinsic and intrinsic toughening mechanisms. Moreover, it is shown that rising R-curves can be achieved with hybrid toughening when compared with falling R-curves obtained with just thermoplastic veil toughening. Fractography revealed that the hybrid toughening constrained the crack predominantly within the veil region, making it harder to grow and absorb more energy.

Polydopamine-modified HKUST-1 as nanofiller of PPS@PA membrane with well improved desalination performance

In order to improve the permeability and desalination performance of the thin-film nanocomposite (TFN) membranes supported by polyphenylene sulfide ( PPS ), the polydopamine (PDA) modified HKUST-1 (mHKUST-1) nanocomposite materials were added into polyamide ( PA ) functional layer. The mHKUST-1 nanoparticles with good dispersity and chemical compatibility were successfully embedded in PA layer to develop a new negative charged nanofiltration membrane. The optimized PPS/12-mHKUST-1@PA membrane showed an excellent permeability of up to 27.35 L∙m −2 h −1 ∙bar −1 , twice as much as the PPS@PA membranes. Meanwhile, the considerable rejection performance of 91.67% to MgSO 4 and 90.06% to Na 2 SO 4 at 4 bar was mainly up to the repulsive effect of negative charge on membrane surface. Moreover, the PPS/mHKUST-1@PA membranes also has stable filtration performance under long time operation. The results suggested that the membrane modification method in this work have great potential for applications in desalination. • The perfect separation layer by mHKUST-1 nanoparticles combined well with PA layer. • Improving the permeability and desalination performances of TFN membranes significantly. • Negatively charged of TFN membranes surface for the separation of sulfate and hydrochloride.

3D printing of continuous carbon fiber reinforced polyphenylene sulfide: Exploring printability and importance of fiber volume fraction

Additive manufacturing (AM) of thermoplastic polymer composites is rapidly advancing in the aerospace industry. Here, fused deposition modeling (FDM) of continuous carbon fiber reinforced polyphenylene sulfide (CCF/PPS) was explored and involved experimental filaments with nominal fiber volume fractions (V f ) ranging from 30% to 50%. The printability was evaluated using a design of experiments to quantify the contribution of process parameters to the printed filament quality, which considered microstructure, surface texture and both the thermal and mechanical properties. Results showed that nozzle height, nozzle temperature, printing speed, and flow rate were most influential parameters to the printing process; the relative importance of the printing parameters depended on the V f . The filament with 50% V f was successfully printed despite its high fiber volume fraction and achieved an average ultimate tensile strength of 1930 ± 150 MPa, which sets a new benchmark in strength for composites developed by AM. Nevertheless, there are challenges to achieving that strength in printed components. • Fused filament fabrication of an experimental continuous carbon fiber reinforced polyphenylene sulfide. • High volume fraction of fibers achieves tensile strength approaching 2GPa. • Parametric dependence in printed material quality depends on fiber volume fraction.

Metallization of Polyphenylene Sulfide by Low-Cost Mussel-Inspired Catechol/Polyamine Surface Modification

Metallization of Polyphenylene Sulfide by Low-Cost Mussel-Inspired Catechol/Polyamine Surface Modification

Highly Dispersed Co-, N-, S-Doped Topological Defect-Rich Hollow Carbon Nanoboxes as Superior Bifunctional Oxygen Electrocatalysts for Rechargeable Zn-Air Batteries.

Rechargeable Zn-air batteries have received extensive attention due to their use of nontoxic materials, safety, and high energy density. However, the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) at the air electrode of Zn-air batteries both suffer from slow kinetics, limiting their commercialization development. Herein, we prepared Co, N, and S co-doped hollow carbon nanoboxes (Co-N/S-CNBs) rich in topological defects using polyphenylene sulfide (PPS) as a sulfur-rich carbon source. Critically, by utilizing the self-propagating high-temperature synthesis (SHS), PPS can avoid melting, while simultaneously enabling the catalyst to take on a unique hollow structure. Additional post-treatment to introduce Co and N atoms as active centers further increases the defect sites and microporous structures of the catalyst. Under alkaline electrolytes, the Co-N/S-CNBs enabled Zn-air batteries to exhibit excellent bifunctional catalytic activity for both ORR and OER, surpassing commercial catalysts. Chemical analysis showed that the cracking loss of small molecules from PPS during pyrolysis is the main reason for the formation of topological defects, where the defect sites act as active centers to enhance the catalytic performance. Overall, this work provides new insights into the mechanism of how defects are formed in such a catalyst, as well as shows how a high-performance bifunctional electrocatalyst can be utilized for practical Zn-air batteries.

The Investigation the thermal characteristics of polyphenylene sulfides

The article presents the results of a study of the chemical structure, low molecular weight impurities and heat stability according to TGA/DTA of domestic polyphenylene sulfides (PPS) with different molecular weight and their imported analogues. It is shown that domestic samples are almost identical to imported analogues and can be used as a binder for highly filled reinforced polymer composite materials for structural purposes.

Development and Performance Evaluation of an Intelligent Sand Control Screen Based on Polyphenylene Sulfide.

Open hole combined with a sand filter pipe is the main development mode of an unconsolidated sandstone horizontal well, which causes problems such as shaft wall collapse, sand filter pipe blockage, and even damage. At present, the polyurethane intelligent sand control screen pipe can effectively solve these problems, but its application scope is limited by the downhole temperature and material strength. Therefore, the high-strength shape memory polyphenylene sulfide (SMPPPS) was synthesized by an indoor experiment, then the shape memory performance was analyzed, and the variation law of pore size with composition and processing technology was obtained. Finally, the performance of the SMPPPS intelligent screen was evaluated. It is found that (1) with the increase of the cross-linking agent content, the melt index and melt peak temperature of SMPPPS decrease rapidly at first and then remain unchanged; the cross-linking agent content is set at 4.5 wt %. (2) The shape memory performance of SMPPPS is good, and the recovery ratio can reach 99.8% at 110 °C in 11.8 min. (3) The relationship between the pore size distribution proportion of SMPPPS and the foaming agent content, pore enhancer content, temperature, and pressure is determined through experiments; the main distribution range of pore size increases with the increase of the foaming agent content and temperature and decreases with the increase of the pore enhancer content and pressure. When the foaming agent content is 0.5 wt %, the pore enhancer concentration is 10 wt %, the molding temperature is 320 °C, the molding pressure is 10 MPa, and the main distribution range of pore size is 80–320 μm. (4) The permeability of recovery SMPPPS with a compression ratio of 300% first increases slightly and then decreases slightly with the increase of flow, with a variation range of 420.5–463 mD; the compressive strength range is 9.5–11.4 MPa; the SMPPPS has good adaptability to downhole fluid; the sand retaining accuracy is higher than that of the screen sand filter pipe, but the blockage is more serious.

Preparation and bonding mechanisms of polymer/metal hybrid composite by nano molding technology

Abstract With the development of nano molding technology (NMT), the polymer/metal hybrid (PMH) composites have made great progress in industries like automobile, aircraft, and boat. The bonding structure and bonding strength are the key factors ruling the application of PMH. In this work, the PMH containing polyphenylene sulfide (PPS) and Al alloy was prepared by NMT, and the surface treating of Al alloy and the bonding mechanism of PMH has been studied. The results reveal that the bonding strength between metal and polymer shows dependence on the pore structure of the metal surface, which could be controlled by changing the anodizing voltage and time. The PMH in which the Al plate was anodized at 15 V for 6 h achieves the best bonding strength of 1,543 N. The morphological analysis reveals that there forms an anchor and bolt structure in the interface of PPS and Al plate, which bonds the polymer and metal tightly. In addition, the chemical interaction between PPS and Al was confirmed by attenuated total reflection (ATR) infrared spectroscopy, which indicates that both physical and chemical effects contribute to the bonding strength of the PMH. This PMH has great potential of being used as alternative to traditional pure metal components, especially the packing materials of automobiles, electronic products, and furniture.

One-step fabrication of self-cleaning superhydrophobic surfaces: A combined experimental and molecular dynamics study

A simple one-step approach was developed to fabricate self-cleaning superhydrophobic surfaces by soaking the copper substrates into a mixed solution containing zinc oxide, stearic acid and polyphenylene sulfide molecules. X-ray photoelectron spectra confirmed that the hybridization between organic polymers and inorganic molecules happened. Further scanning electron microscopy analyses revealed that hierarchical structure was formed. A synergy between modified surface chemistry and surface roughness provided copper substrates with superhydrophobic properties and good self-cleaning performance. The fabricated superhydrophobic surfaces exhibited a water contact angle as high as ∼164.7 ± 1.5° and a sliding angle as low as ∼4.0 ± 0.8°. Molecular dynamics simulations were applied to study the adsorption behavior of stearic acid molecules on the zinc oxide crystal surfaces and the wettability of water molecules on as-prepared surfaces at molecular level. Molecular dynamics simulation results illustrated that the hydrophilic interactions between water droplets and zinc oxide surfaces involved hydrogen-bond formation, whereas the hydrophobic interaction between water molecules and superhydrophobic surfaces involved Van der Waals's interaction between the alkyl chains.

Simulation Analysis of Polyphenylene Sulfide Composite for Two-Folded Clip Panel by Using Aniform Software

Out of autoclave composite manufacturing is a process that achieves same quality as an autoclave process but through different method and one of them is thermoforming process in which, it can save the process cost and time. Recently, the fabrication process to fabricate thermoplastic composites by using thermoforming method becoming more popular among the thermoplastic research area. The simulation process is applied to enable the prediction of defects as well as to study the behavior of the process at early stage using simulation analysis to avoid trial and error during fabrication. To simulate the simulation, there are several factors and parameters need to be considered so that the defects could be avoided due to the excellent and poor formability will be linked between the fabricated samples in Aniform and the manufactured products. In this study, Two-Folded Clip panel mold type has been chosen to simulate the fabrication process. The results show the tensioner of AUY-50 is the best tensioner to be used in this research due to the significant of the result of press formed laminate quality with no voids appeared.