Polyphenylene Sulfide Research Articles

Design and manufacture of long fiber thermoplastic composite frost plate for water meter protection

Long fiber thermoplastics (LFT) composites have been increasingly used in various applications because they possess great mechanical properties and excellent processability. Other advantages of using LFT composites include low cost and exceptional corrosion resistance, enabling them to be candidates for corrosion-prone applications. This work focuses on the design, validation, and prototyping of a water meter frost plate using long glass fiber reinforced thermoplastic composites. Before prototyping, the LFT composite frost plates were modeled with finite element analysis for iteration and evaluation. The deflection and stresses responses under normal and freezing operation conditions were simulated to validate the functionalities of a slip-on feature, resistance to nominal water pressure, and self-sacrifice capability. After validation of the functionality of self-sacrifice and protection of the water meter, frost plates were prototyped with an extrusion compression molding process using LFT glass fiber reinforced polyphenylene sulfide (glass/PPS) and LFT glass fiber reinforced nylon 66 (glass/nylon 66). The molded LFT composite frost plate was tested in normal and frozen operation conditions to evaluate its performance. It was found that the designed frost plate was able to prevent water leakage from normal water pressure and protect the water meter as designed by fracturing at the bolt area when the water freezes. The fracture location matched well with the maximum stresses observed from the modeling result. It is concluded that LFT composites can be an alternative material to replace the metallic counterpart to provide protection for the water meter during freezing conditions.

Advanced PPS/MOFs composite nanofiltration membranes derived from contra-diffusion synthesis for precise molecular separation

To meet the separation requirements of polyphenylene sulfide (PPS) membranes in extremely harsh environments and to enhance the separation performance of PPS membrane material, this study utilizes Zeolitic imidazolate framework (ZIF) material with a porous structure to modify the structure of the PPS membranes. Using the Contra-diffusion synthesis method, we successfully created PPS composite membranes that were modified by ZIF-8. At the end of the three-hour reaction time, a continuous and dense layer of ZIF-8 crystals with uniform crystal size and regular crystal shape was produced on the matrix membrane's surface. The permeance to rhodamine B aqueous solution is 42.54 L m−2 h−1 bar−1, and the retention rate is 99.5 %, which has high permeability and retention performance. In the anti-pollution performance test, the composite membrane's flux recovery rate is 72.9 %, which has good anti-pollution performance. After immersion in strong acids, strong alkalis, and a variety of organic solvents, the appearance shows no evident flaws, and the separation performance in strong alkalis and five different types of organic solvents stays steady, demonstrating excellent alkali and solvent resistance. This proves that composite membranes have great potential for application in dye wastewater treatment.

Fabrication of advanced polyphenylene sulfide composites by in-situ grafting of sulfide silane and PCPA on glass fibers

The energy crisis has driven increased adoption of electric vehicles (EVs) in the automotive sector, with a focus on lightweight engineering plastics (EPs) for fuel efficiency. This study aims to enhance the mechanical properties and thermal conductivity of EPs to address heat-related concerns in EVs and electronic devices. A hybrid filler (milled glass fiber, boron nitride, and graphene oxide) was introduced to polyphenylene sulfide (PPS), using a simultaneous grafting process with poly(catechol/polyamine) (PCPA) and silane additives. Filler aggregation in the resin matrix was overcome with surface-treatment agents such as Bis[3-(triethoxysilyl)propyl] tetrasulfide (Si69), catechol, and tetraethylenepentamine. PCPA polymerization on the filler surfaces bridged connections between fillers and silane molecules. The resulting surface-treated hybrid composite showed a 637% increase in thermal conductivity (2.102 Wm−1K−1) and a 63.94% increase in tensile strength (65.87 MPa) compared to the base matrix. Incorporating 40 wt.% surface-treated mGF, 30wt.% raw BN, and 6wt.% surface-treated GO, along with PCPA and Si69 treatments, achieved this improvement. The hybrid filler composites significantly enhanced thermal conductivity and mechanical properties, providing a rapid and convenient solution to challenges in robustness and heat dissipation for electronic vehicles and devices.

Dense integration of chlorocatechols crosslinked polyphenylene sulfide solid-state separator for Li Metal-Free Batteries

Dry electrode film fabrication technology, known for its environmental friendliness and low energy consumption, is recognized as an effective industrial approach for producing highly dense solid-state electrolytes and pore-free separators. It holds promise for applying thin lithium metal and Li metal-free anodes in ultra-high energy density Li-ions batteries. However, the films produced by this method suffer from issues such as poor toughness, low strength, uneven thickness, and difficulties in rewinding, which limit its widespread adoption in the large-scale manufacturing of lithium batteries. In this study, we propose a hydrothermal process to introduce a chlorocatechol-based cross-linker onto the surface of highly crystalline polyphenylene sulfide (PPS) powder. By employing the dry electrode process, a PPS-based solid-state separator (PPS-SSS) is fabricated, featuring a thin profile (18±2 μm), a smoother surface, and a denser structure, significantly enhancing its mechanical properties. Moreover, the dense integration structure and chlorocatechol groups contribute to a higher Li+ transference number and more effectively inhibit the growth of Li dendrites. Li metal-free batteries, constructed with this separator, a Sn-plated Cu 10 μm foil anode, and a thick high-nickel cathode dry electrode, exhibit high discharge areal and specific capacities (5 mAh cm−2 and 200 mAh g−1, respectively) and pouch battery device energy density exceeding 440 Wh kg−1. Impressively, even in the presence of Cu or Fe powder contamination on the CuSn foil anode or cathode, this separator can still achieve uniform electric field distribution and lithium deposition, demonstrating good cycle stability.

Effect of polyphenylene sulfide content on the properties of injection molding bonded NdFeB magnets

AbstractThe effect of polyphenylene sulfide binder content on the properties of injection molding polyphenylene sulfide/NdFeB magnets were investigated. The maximum filling amount of NdFeB magnetic powder was 87.6 wt.‐%, and the mixing process and subsequent injection molding of the polyphenylene sulfide/NdFeB were in good condition. The melt mass‐flow rate of the polyphenylene sulfide/NdFeB granular materials reached 121.7 g/10 min, the compressive strength of the polyphenylene sulfide/NdFeB magnet was 92.18 MPa, and its maximum magnetic energy product reached 5.59 MGOe. The structure and morphology characteristics of polyphenylene sulfide/NdFeB magnets were investigated using scanning electron microscopy and atomic force microscopy. The corrosion behavior of polyphenylene sulfide/NdFeB magnets was also studied using potentiodynamic polarization curves and electrochemical impedance spectroscopy. The results indicated that the injection molding process facilitated the uniform coating of polyphenylene sulfide particles on NdFeB powder, which directly enhanced the corrosion resistance of polyphenylene sulfide/NdFeB magnets. With an increase in polyphenylene sulfide content, the surface of polyphenylene sulfide/NdFeB magnets became more uniform. The corrosion current density of 13 wt.‐% polyphenylene sulfide/NdFeB magnet was approximately one order of magnitude lower than that of 9 wt.‐% polyphenylene sulfide/NdFeB magnet, indicating an improved corrosion resistance of polyphenylene sulfide/NdFeB magnet.

Photo-induced carboxylation of C(sp2)−S bonds in aryl thiols and derivatives with CO2

Aryl thiols have proven to be a useful class of electron donors and hydrogen atom sources in photochemical processes. However, the direct activation and functionalization of C(sp2)–S bonds in aryl thiols remains elusive in the field of photochemistry. Herein, a photochemical carboxylation of C(sp2)–S bonds in aryl thiols with CO2 is reported, providing a synthetic route to important aryl carboxylic acids. Moreover, different kinds of aryl thiol derivatives, benzeneselenol and diphenyl diselenide also show moderate-to-high reactivity in this transformation. Mechanistic studies, including DFT calculations, suggest that the in situ generated carbon dioxide radical anion (CO2•−) and disulfide might be the key intermediates, which undergo radical substitution to yield products. This reaction features mild and catalyst-free conditions, good functional group tolerance and wide substrate scope. Furthermore, the efficient degradation of polyphenylene sulfide highlights the usefulness of this methodology.

Wear-resistance triboelectric nanogenerator based on metal-organic framework modified short carbon fiber reinforced polyphenylene sulfide

In aerospace, automobile transportation, disaster warning and other fields, triboelectric nanogenerators (TENGs) are a new type of energy harvesting device that converts mechanical energy into electrical energy. It is especially suitable for monitoring and early warning systems in harsh environments. This paper reported a TENG based on composites reinforced polyphenylene sulfide (PPS) by the metal–organic frameworks (MOFs) are constructed on the surface of short carbon fibers (SCF). The friction properties of the composites were investigated by using two different friction methods. The composites demonstrated excellent wear resistance, with reduced wear rates to 8.16 × 10-7 mm3/Nm and 2.512 × 10-7 mm3/Nm, respectively. Additionally, it exhibited outstanding high-temperature stability (445.9 °C). Therefore, the study highlights the potential of TENGs to serve as a sustainable solution for real-time environmental monitoring, paving the way for the development of robust and energy-efficient systems in harsh environment applications.

Determination of the degree of crystallinity of polyphenylene sulfide composited with crystalline and non-crystalline fillers by applying the direct derivation method. Corrigendum

An erroneous equation and some values of related parameters in the paper by Toraya [J. Appl. Cryst. (2024), 57, 1115–1126] are corrected.

Infrared on-site heating for material extrusion additive manufacturing of carbon fiber filled polyphenylene sulfide and its nano-graphene-reinforced alternatives

This study investigates the impact of infrared heating and annealing on the mechanical properties of carbon fiber-reinforced polyphenylene sulfide (CF-PPS) and graphene nanoplatelet (GNP)-reinforced CF-PPS composites in Material extrusion (MEX) additive manufacturing. GNP/CF-PPS composites are prepared by mechanically mixing CF-PPS plastic particles with GNP particles and subjecting them to infrared heating and annealing treatments during the three-dimensional (3D) printing process. Three-point bending tests assess the mechanical properties of the samples. The results reveal that the 0.03 wt.% GNP/CF-PPS sample, subjected to infrared heating followed by annealing, exhibits a 30% increase in bending strength compared to pure CF-PPS, demonstrating that the combined treatment significantly enhances mechanical performance. Microscopy observations using a Keyence VH7000 digital optical microscope and a scanning electron microscope (SEM) confirm that GNP addition and infrared irradiation lead to reduced surface roughness and fewer fracture cross-sectional pores. The interlayer bonding improves notably, indicating enhanced internal density and structural stability. Furthermore, differential scanning calorimetry analysis shows a 20% increase in crystallinity for heat-treated samples, contributing to better interlaminar bonding and reduced temperature gradients during printing. Finite element simulations using MATLAB and ABAQUS software corroborate these findings, demonstrating that infrared heating proves more effective than varying GNP content alone in reducing deformation, residual stress, and temperature differences during the MEX process. These results provide valuable insights into improving the mechanical properties and stability of MEX-manufactured large-dimensional composite materials through optimized thermal management.

Functional organic adlayers for controlling the adhesion strength of electrolessly deposited copper on super-engineering plastics

Effective metallization of super-engineering plastics such as liquid crystal polymers (LCP) and polyphenylene sulfides (PPS) via electroless deposition of copper thin films is an important step in the manufacturing of a wide range of devices. Copper deposition typically requires a pre-treatment step involving chemical and/or mechanical roughening to ensure high adhesion at the polymer/Cu interface; however such treatments are detrimental to patterns and topographic features of the polymer that possess µm resolution and/or high aspect ratio. Herein, we demonstrate that it is possible to regulate and improve adhesion of electrolessly deposited copper thin films at LCP and PPS materials via multilayer functionalization with aryldiazonium cations of a p-aminobenzoic acid precursor. We first demonstrate that aryldiazonium grafting conditions can be optimized to overcome the chemical inertness of LCP/PPS without resorting to harsh oxidative or mechanical treatments. We then show that the density of Ar-COOH groups can be regulated by modifying the number of functionalization cycles. X-ray photoelectron spectroscopy studies shows that this has a clear impact on the composition of the catalytic nanoparticle layer required for copper deposition. Adhesion strength studies demonstrate that such changes translate into improved adhesion strengths without any adverse effects on surface roughness. Control experiments with alternative chemical moieties suggest that specific chemical interactions between catalytic seeds and grafted carboxylate groups play an important role in the observed improved adhesion.

Rheology and Processing of High-Strength Liquid Crystal Polymer Reinforced Thermoplastic Composite Materials

Liquid crystal polymer (LCP) composites are presented as lightweight, high-strength, thermoplastic composites. Fumed silica (FS), carbon black (CB), carbon nanostructures (CNS), and boron nitride (BN) added to the polyphenylene sulfide (PPS) increased the viscosity ratio of the PPS to the LCP. PPS filled with 5 wt.% FS was used to optimize injection molding conditions and had a viscosity ratio ranging from 2 to 13. Increasing fill time to 5 s brought about the highest tensile strength of 99 MPa and modulus of 12.5 GPa, while the tool and melt temperatures imparted no significant effect. Mechanical and thermal properties of select LCP materials processed using molding conditions optimized for the experimental materials are presented. Mechanical properties in the crossflow direction were lower than in the flow direction, which could be overcome with tool design and placement of valve gates to tailor the flow patterns. BN filled composites increased the thermal conductivity to a value of 0.26 W/mK at 16 wt.% loading.

Ply-ply friction behavior between unidirectional thermoplastic prepreg plies during thermoforming: Characterization and modeling

The ply-ply friction behavior of unidirectional carbon fiber reinforced polyphenylene sulfide (UD CF/PPS) prepreg in thermoforming was investigated through an improved pull-through testing system. The effects of temperature, normal force and slipping velocity were considered in testing. The results indicated the existence of three key mechanisms underlying slipping: namely the resin shear, fiber–fiber contact and fiber-resin interaction. A three-stage division of the experimental curve was proposed, and several factors were defined to establish a quantitative definition of the ply-ply friction behavior. The results showed that the influence of slipping velocity is particularly evident. Its post-yield stress (12.8 kPa), steady-state CoF (0.118) and residual stress (0.705 kPa) were the highest, exhibiting the largest changes of 957.9 %, 736.9 % and 47.2 %, respectively. This indicated the strong contribution of resin in ply-ply friction. In addition, the Stribeck analysis also suggested the dominance of hydrodynamic lubrication condition in slipping. Based on the experimental results, a simple phenomenological model was proposed based on experimental curves to accurately describe the effects of processing parameters. This work presents a comprehensive characterization of the ply-ply friction behavior of UD CF/PPS prepreg in thermoforming, providing a substantial experimental foundation for the subsequent simulation research.

A novel mechanism to accelerate stress relaxation of toughened blends: Stress-induced core-shell morphological reconstruction and its application in thermoforming and dimensional stabilization

Improving thermoforming efficiency and dimensional stability in thermoplastic products is a common challenge. This study investigates toughened polyamide 612 (PA612) blends made by adding maleic anhydride-functionalized SEBS (mSEBS) elastomers, along with high-density polyethylene (HDPE), polyphenylene Oxide (PPO), and polyphenylene Sulfide (PPS). Analyses showed that mSEBS forms a core-shell structure with HDPE or PPO and a sea-island structure with PPS in the PA612 matrix. The study uniquely examines how these structures affect stress relaxation. The results, modeled by a steady-state creep model, revealed that the core-shell structures reduced the characteristic relaxation time (λ) by over three orders of magnitude compared to PA612/mSEBS blends. Additionally, PA612/mSEBS/HDPE blends were more temperature-sensitive, reducing λ by six orders of magnitude compared to PA612/mSEBS/PPO blends. Further analysis showed that stress-induced core-shell morphological reconstruction (SCMR) significantly improved stress relaxation by promoting extensive plastic deformation and energy dissipation. These toughened PA612 blends exhibited excellent thermoforming efficiency and dimensional stability. A 3D finite element model confirmed SCMR as an effective strategy for stress relaxation, providing valuable insights for designing toughened blends with superior processing efficiency and stability.

Directivity Improved Antenna with a Planar Dielectric Lens for Reducing the Physical Size of the On-Vehicle Communication System.

As the physical size of a communication system for satellites or unmanned aerial vehicles demands to be reduced, a compact antenna with high directivity is proposed as a core element essential to the wireless device. Instead of using a horn or an array antenna, a unit planar antenna is combined with a surface-modulated lens to convert a low antenna gain to a high antenna gain. The lens is not a metal-patterned PCB but is dielectric, which is neither curved nor very wide. This palm-sized lens comprises pixels with different heights from the backside of PolyPhenylene Sulfide (PPS) as the dielectric base. The antenna gain from the unit antenna of 4.5 cm × 4.5 cm is enhanced by 10 dB with the help of a compact dielectric lens of 7.5 cm × 7.5 cm at 24.5 GHz as the frequency of interest. The antenna design is verified by far-field measurement as well as near-field observation, including sensing a metal object behind a blocking wall by using an RF test bench. Moreover, antenna performance is understood by making a comparison with conventional designs of antennas in terms of directivity and physical sizes.

High-Performance Composite Membranes: Embedding Yttria-Stabilized Zirconia in Polyphenylene Sulfide Fabric for Enhanced Alkaline Water Electrolysis Efficiency.

Due to their excellent alkali resistance and chemical stability, polyphenylene sulfide (PPS) fabric membranes are widely used in alkaline water electrolysis (AWE) for hydrogen production. However, traditional PPS membranes suffer from poor hydrophilicity, low airtightness, and high area resistance, resulting in high energy consumption and reduced safety in industrial applications. This study addresses the aforementioned issues by coupling 3-(2,3-epoxy propoxy) propyl trimethoxy silane (KH560) via self-condensation to the PPS membrane and blending it with self-synthesized yttrium-stabilized zirconia nanoparticles (YSZNPs). The YSZNPs are loaded onto the modified PPS fiber surface through dip-coating and hot-pressing processes, forming a micro-mechanical interlocking structure that enhances the overall performance of the membrane in practical hydrogen production applications. The findings indicate that the developed composite membrane demonstrate outstanding hydrophilicity, minimal area resistance (0.21 Ω cm2), and elevated bubble point pressure (2.93224bar). Significantly, tests on gas purity indicate that the produced hydrogen and oxygen attain purities of 99.90% and 99.75%, respectively, when evaluated at a current density of 1.5 A cm-2. Moreover, after 500h of electrolysis testing in a simulated industrial environment, minimal decline in membrane performance is observed, highlighting the competitive edge of this composite membrane in the current AWE market.

Corrosion-Resistant Polymer Composite Tubes with Enhanced Thermal Conductivity for Heat Exchangers

The heat transfer surfaces of heat exchangers are usually made of metals which may suffer from severe corrosion. When corrosive fluids are present, highly corrosion-resistant metals, graphite or ceramics are used, resulting in high costs. This study presents measured data on the thermophysical and mechanical properties of recently developed corrosion-resistant polymer composite tubes for use in heat exchangers. Extruded polymer composite tubes based on polypropylene or polyphenylene sulfide filled with graphite flakes were investigated. The anisotropic thermal conductivities of the polymer composite tubes were measured at various temperatures. The through-wall thermal conductivity of the tubes made of polypropylene filled with 50 vol.% graphite is increased by a factor of 30 compared to pure polypropylene, resulting in a thermal conductivity of 6.5 W/(m K) at 25 °C. The tubes composed of polyphenylene sulfide filled with 50 vol.% graphite have a through-wall thermal conductivity of 4.5 W/(m K) at 25 °C. The mechanical properties of the polymer composites were measured using tensile and flexural tests at different temperatures. The composite materials are more rigid and keep their mechanical properties up to a higher temperature level compared to the unfilled polymers. Surface roughness measurements show the very smooth and sealed surface of the composite tubes. The results contribute to establishing the viability of using polymer composites for heat exchanger applications with corrosive fluids.

Reinforcement and Controlling the Stability of Poly(ε-caprolactone)-Based Polymeric Materials via Reversible and Movable Cross-Links Employing Cyclic Polyphenylene Sulfide.

Due to its biodegradation ability, poly(ε-caprolactone) (PCL) is a suitable alternative for packaging materials; however, its biodegradation can also lead to instability in its usage. Cyclic polyphenylene sulfide (7U) has been shown to form rotaxane structures with PCL by simple blending to generate the π-π stacking effect and movable cross-link. A 2-fold increase in toughness and no decrease in Young's modulus for the PCL-based polyurethane with 7U are observed. The rotaxane structures mainly exist in the amorphous regions and have no impact on the crystallinity of PCL. Under the catalysis of lipase in aqueous solution, the stability of PCL is improved due to the 7U's suppression of the attack from the enzymes on PCL. After dissolution of the PCL films in the organic solvent, the dispersion of 7U and the breakage of the cross-links lead to little suppression on degradation during the catalysis of lipase. Thus, the controlled stability of PCL using 7U can prolong the life span of the biodegraded PCL materials.

Frontal Impact Energy Absorbers for Passenger Cars.

Road accidents cause considerable losses to road users and to society. The steady increase in the number of vehicles leads to increased traffic volume. Therefore, there is a real need to improve passenger safety by developing passive safety systems. This article presents the results of experimental tests of structures absorbing kinetic energy, which could be used in the front section of a vehicle in order to reduce the consequences of passenger car head-on collisions. A number of crash tests of selected structures were conducted under various load conditions. An analysis was carried out of parameters enabling the authors to assess the level of energy absorption by the absorbers made, and compare these to absorbers available on the market. The tests carried out made it possible to determine energy absorption capability of the crash boxes prepared and to identify a structure exhibiting the most advantageous properties from the point of view of its prospective use. Of all of the absorbers analysed, in the context of energy absorption, it was the absorber made of glass-fibre-reinforced polyphenylene sulphide that produced the most advantageous results. Nonetheless, favourable results were obtained for all of the structures tested.

Complex Permittivity Spectra of Granular Polymer Composites with Dispersed Ag-Coated Cu Flakes

Conductive particle-containing granular composites with tuneable negative permittivity are being studied to improve the performance of electromagnetic devices, such as shielding materials. In this study, we investigated the relative complex permittivity and electrical conductivity of granular composites of polyphenylene sulfide (PPS) resin and Ag-coated Cu flakes in the radio- to microwave-frequency range and compared them with those of PPS/bare Cu flake composites. Electrical conductivity measurements revealed that the PPS/Ag-coated Cu flake composites have a lower percolation threshold (φc) than the PPS/bare Cu flake composites, whereas the electrical conductivity of the PPS/Ag-coated Cu flake composites in the percolated particle state was higher at the same particle volume fraction. At particle contents above φc, a low-frequency plasmonic state of conduction electrons was achieved in the percolated particle chains in both composites, and negative permittivity spectra were obtained. The percolated PPS/Ag-coated Cu flake composites had a negative permittivity up to a higher frequency than the percolated PPS/bare Cu flake composites. Furthermore, the Drude model was used to analyze the negative permittivity spectra of the composites in the percolated particle state. The plasma frequency of the composites with percolated Ag-coated Cu flakes was higher than that of the composites with percolated bare Cu flakes. Thus, coating Ag on Cu particles improved the conductivity of the composite, leading to negative permittivity up to higher frequencies. This study contributes to the enhancement of the negative permittivity achieved by granular composites, which is useful for microwave technology applications.Graphical

Enhancing filler ratio and thermal conductivity of polyphenylene sulfide composites using molybdenum sulfide and carbon nanotubes: A layer-by-layer hot-pressing approach

In this study, we aimed to address challenges in thermal management and structural applications by developing composite materials with enhanced thermal conductivity and insulation properties. Our approach involved combining two-dimensional MoS2 nanosheets with carbon nanotubes (CNTs), leveraging their respective properties to create synergistic effects. MoS2, renowned for its remarkable electrical and mechanical attributes, was synthesized via a hydrothermal reaction and subsequently exfoliated using liquid-phase exfoliation techniques. Meanwhile, CNTs were surface-treated to prevent aggregation and ensure optimal dispersion within the composite matrix. These treated CNTs were then entangled with MoS2 nanosheets to form layered structures, facilitating the creation of efficient heat transfer pathways. The resulting MoS2-CNT composites were fabricated using a hot-pressing method, with polyphenylene sulfide (PPS) layers integrated for structural integrity. Through experimental investigation and characterization, our composites exhibited substantial improvements in thermal conductivity, achieving an impressive 5.77 W/mK. Additionally, the incorporation of PPS layers endowed the composites with insulation properties, further enhancing their suitability for diverse applications. Notably, the composite demonstrated a tensile strength of 67 MPa, indicating its potential for structural applications. This research underscores the promising potential of MoS2-CNT composites in addressing critical challenges in thermal management and structural engineering across various industries, including automotive and electronics. By offering a comprehensive solution that combines enhanced thermal conductivity, mechanical strength, and insulation properties, our composite material opens avenues for innovation in the development of advanced materials for next-generation technologies.