Phenylene Sulfide Research Articles

Surface Modification of Sulfur-Assisted Reduced Graphene Oxide with Poly(phenylene sulfide) for Multifunctional Nanocomposites.

The sulfur on the sulfur-assisted reduced graphene oxide (SrGO) surface provides the origin of poly(phenylene sulfide) PPS-grafting via SNAr mechanism. In-situ polymerization from sulfur on SrGO afforded surface modification of SrGO, resulting in enhanced dispersibility in PPS. The tensile strength, electrical and thermal conductivities, and flame retardancy of PPS-coated SrGO were efficiently enhanced using highly concentrated SrGO and masterbatch (MB) for industrial purposes. Three-dimensional X-ray microtomography scanning revealed that diluting MB in the PPS resin afforded finely distributed SrGO across the PPS resin, compared to the aggregated state of graphene oxide. For the samples after dilution, the thermal conductivity and flame retardancy of PPS/SrGO are preserved and typically enhanced by up to 20%. The proposed PPS/SrGO MB shows potential application as an additive for reinforced PPS due to the ease of addition during the extrusion process.

Investigation on thermal degradation mechanism of poly(phenylene sulfide)

Thermal degradation occurs inevitably during the practical processing of poly(phenylene sulfide) (PPS) due to its low thermal stability, leading to the deterioration of processability and performance of PPS products. In this study, the structural evolution of PPS during thermal degradation in nitrogen (N2) and oxygen (O2) atmospheres are investigated systematically via X-ray photoelectron spectra (XPS), fourier transform infrared spectroscopy (FT-IR), gel permeation chromatography (GPC) and dynamic rheology. A rheological measurement is proposed to distinguish the multi-stage degradation behaviors of PPS efficiently. It is found that the thermal degradation mechanism of PPS differs considerably in N2 and O2 atmospheres. Chain scission is predominant when PPS is heated in N2, while CS and CC crosslinking structures can only be initiated at extremely high temperature. On the contrary, oxidation of PPS is accelerated seriously in the presence of O2. Chain extension and branching reactions are activated even at low processing temperature of PPS, and substantial COC crosslinking structures are created which leads to the sharp increase of melt viscosity. Furthermore, the change of crystallization behaviors after thermal treatments of PPS are also studied by differential scanning calorimetry (DSC) and polarized optical microscopy (POM). The crystalline kinetics of PPS changes significantly during melt processing, which further corroborates the thermal degradation mechanism of PPS.

Insight into the Excellent Tribological Performance of Highly Oriented Poly(phenylene sulfide)

Insight into the Excellent Tribological Performance of Highly Oriented Poly(phenylene sulfide)

Synthesis of colorless and high-refractive-index sulfoxide-containing polymers by the oxidation of poly(phenylene sulfide) derivatives

A series of poly(phenylene sulfide) (PPS) derivatives can be bleached while maintaining high refractive indices, by partially incorporating sulfoxide bonds through their mCPBA oxidation, owing to the loss of lone pairs around the sulfide atoms.

A review on research, application, processing, and recycling of PPS based materials

Among the engineering thermoplastics, poly(phenylene sulfide) (PPS) stands out for its excellent properties and mainly for processing at lower temperatures. The requirements requested by industries can be made by improving mechanical strength, weight reduction, and durable components by reinforcing the PPS matrix with fiberglass (FG) and carbon fiber (CF). This review intends to present the most current research related to the physical, mechanical, and thermal properties of PPS and the PPS/FG and PPS/CF composites most currently used by the aerospace, automotive, and energy industries. In addition to presenting the feasibility of mechanical and thermal recycling processes for PPS-based waste to reinsert a high market value thermoplastic into the industrial production cycle, thus contributing to the minimization of waste destined for landfills and incinerated or even improperly disposed of in the environment.

Stress Concentration in Open Hole Laminate Composites Under Bending: Potential Application in Dental Implant Prosthesis

Carbon fiber reinforced polymer (CFRP) have been gaining prominence in replacing metallic alloys for infrastructure in prostheses, with the possibility of edentulous patients to acquire fixed prostheses. For this, procedures are required to connect these implants to the implant-supported fixed prosthesis, such as holes and notches that can reduce their mechanical properties. In addition, the infrastructure requires longer cantilevers, causing greater stress on the prosthetic system. Then, the objective is to analyze the stress concentration in the CFRP subjected to bending loads with holes (4 and 6 mm diameter to verify the influence of the diameter-to-width ratio) in four-point-bending test. Two composite laminates were evaluated: one with thermoplastic matrix of poly(phenylene sulphide) PPS; and another with epoxy matrix combined with carbon fibers fabric. The presence of holes in the studied dimensions did not present significant differences in the flexural modulus and maximum bending strength. Therefore, the use of CFRP showed some advantage regarding the reduced effect of stress concentration compared to metallic alloys.

Evaluation of polyphenylene sulfide by surface thermodynamics approaches: Comparison with common polymers

AbstractPoly(phenylene sulfide) (PPS) is an advanced thermoplastic and widely used in industrial applications requiring high performance. Research on improving the surface properties of PPS is still ongoing and a detailed surface free energy (SFE) knowledge of this polymer is necessary for its applications related to surface wettability. In this study, wettability characteristics of PPS were evaluated by SFE calculations. For this purpose, the apparent contact angles of nine different test liquids having various surface tensions were measured on the PPS surface by the sessile drop method. After that, the dispersive and polar components of SFE were calculated using geometric (Owens and Wendt's method) and harmonic (Wu's method) mean approaches. The Lifshitz‐van der Waals, acidic and basic components of SFE were calculated using van Oss‐Chaudhury‐Good method. Additionally, the surface tension values of PPS were also determined by equation of state, Zisman's critical surface tension and Fowkes' approaches. In the present study, the effects of calculation methods and selected liquid pairs on SFE parameters were systematically investigated. It was found that selected liquid pairs and calculation methods affected the SFE considerably. The reasons for this were examined and the SFE components of PPS was compared with some common polymers for better evaluation.

Cyclic (phenylene sulfide) treated carbon fiber for facile preparation of high performance PEEK based anti-wear composites

Improving the surface activity of carbon fiber (CF) via a sizing agent is an efficient approach to enhance the performance of CF reinforced polymer composites. However, the conventional sizing agents usually readily decompose at high temperature. In this work, a novel heat resistant sizing agent is coated directly on the CF surface by in-situ thermal ring-opening polymerization of cyclic phenylene sulfide oligomers (CPS) in air. Studies indicate that the novel sizing agent is oxygenated poly (phenylene sulfide) (PPS), possessing high temperature stability. Properties of the PPS sized CF (CF-CT) filled PEEK based composite are investigated by using the original CF/PEEK composite as a reference. The results reveal that the CF-CT composite exhibit significantly higher tensile strength, lower average friction coefficient and wear rate when CF content exceeds 20 wt%. It is reasonably ascribed to the stronger interface interaction between the PPS sized CF and PEEK, which effectively promotes the enhancement effect of CF in the composite material.

Preparation of Recyclable and Versatile Porous Poly(aryl thioether)s by Reversible Pd-Catalyzed C-S/C-S Metathesis.

Porous organic materials (polymers and COFs) have shown a number of promising properties; however, the lability of their linkages often limits their robustness and can hamper downstream industrial application. Inspired by the outstanding chemical, mechanical, and thermal resistance of the 1D polymer poly(phenylene sulfide) (PPS), we have designed a new family of porous poly(aryl thioether)s, synthesized via a mild Pd-catalyzed C–S/C–S metathesis-based method, that merges the attractive features common to porous polymers and PPS in a single material. In addition, the method is highly modular, allowing to easily introduce application-oriented functionalities in the materials for a series of environmentally relevant applications including metal capture, metal sensing, and heterogeneous catalysis. Moreover, despite their extreme chemical resistance, the polymers can be easily recycled to recover the original monomers, offering an attractive perspective for their sustainable use. In a broader context, these results clearly demonstrate the untapped potential of emerging single-bond metathesis reactions in the preparation of new, recyclable materials.

Poly(phenylene sulfide) Containing Boron in the Main Chain for Shield Thermal Neutron

AbstractThe thermal neutron shielding poly(phenylene sulfide)s containing boron (PPSmBs) are synthesized with sodium sulfide, dichlorobenzene and lithium bis[4‐chlorosalicylato(2‐)]borate (CLBSB) which is prepared with 4‐chlorosalicylic acid and boric acid. The structure of CLBSB is characterized and confirmed with 1H nuclear magnetic resonance spectroscopy (NMR), 13C NMR, 11B NMR and Fourier transform infrared (FT‐IR). CLBSB exhibits excellent thermal stability with 5 % weight loss temperature (T5%) at 434 °C. The structure and the element composition of PPSmBs are analyzed by FT‐IR, energy‐dispersive X‐ray spectroscopy (EDS) and X‐ray photoelectron spectroscopy (XPS). The melting temperature (Tm) of PPSmBs ranges from 280.7 to 284.1 °C, and the crystallization peak temperature (Tc) is in the range of 244.9–255.0 °C. The T5% is 472–492 °C, and tensile strength is 45.8–69.0 MPa, flexural strength is 56.0–106.2 MPa. The thermal neutron shielding properties are evaluated by the small angle neutron scattering spectrometer. The mass attenuation coefficient of PPSmB‐5 is 2.06 cm2 g−1, which is 30 % higher than that of PPS (2.64 cm2 g−1).

Thermally Conductive Composites Obtained by Carbon Nanotubes Filling Immiscible Polyamide 6/Poly (phenylene sulfide) Blends

Thermally Conductive Composites Obtained by Carbon Nanotubes Filling Immiscible Polyamide 6/Poly (phenylene sulfide) Blends

Perfluorocyclobutyl-containing multiblock copolymers to induce enhanced hydrophilic/hydrophobic phase separation and high proton conductivity at low humidity

A multiblock copolymer containing a highly sulfonated poly(phenylene sulfide sulfone) (sPPSS) hydrophilic oligomer and a partially fluorinated perfluorocyclobutyl (PFCB)-containing hydrophobic oligomer was synthesized. The sharp contrast between the hydrophilic and hydrophobic moieties induced a well-developed phase separation, which was observed in the transmission electron microscopy (TEM) images within the polymer electrolyte membrane (PEM). The increased chain mobility from the flexible ether and PFCB groups afforded facile thermal annealing of the membrane. Thermal annealing induced polymer chain packing of the hydrophobic moieties, enhancing the hydrophilic/hydrophobic phase separation. The fabricated membranes exhibited higher proton conductivity compared with those of conventional hydrocarbon PEM possessing a random copolymer architecture, while their dimensional swelling was suppressed. Additionally, under low humidification (a relative humidity (RH) of 50%), the sulfonated–fluorinated membrane achieved a high proton conductivity of up to 41.9 mScm−1. A high adhesion strength of 32.7 mNcm−1 was also observed, indicating strong interfacial compatibility in the membrane electrode assembly (MEA) due to its structural affinity for the contacting perfluorosulfonated binder. The enhanced hydrophilic/hydrophobic phase separations facilitated fuel cell performances of 1.13 and 0.61 Acm−2 at 0.6 V and 65 °C under 100% and 50% RH conditions, respectively, in addition to achieving stable chemical and physical durabilities.

Synthesis of methylated phenylene sulfide polymers via bulk oxidative polymerization and their heat curing triggered by dynamic disulfide exchange

Synthesis of methylated phenylene sulfide polymers via bulk oxidative polymerization and their heat curing triggered by dynamic disulfide exchange

Surface modification of poly(phenylene sulfide) using photoinitiated chlorine dioxide radical as an oxidant

Surface modification of poly(phenylene sulfide) using photoinitiated chlorine dioxide radical as an oxidant

Fatigue Performance of Metal-Composite Friction Spot Joints.

Friction spot joining is an alternative technique for joining metals with polymers and composites. This study investigated the fatigue performance of aluminum alloy 2024/carbon-fiber-reinforced poly(phenylene sulfide) joints that were produced with friction spot joining. The surface of the aluminum was pre-treated using various surface treatment methods. The joined specimens were tested under dynamic loading using a load ratio of R = 0.1 and a frequency of 5 Hz. The tests were performed at different percentages of the lap shear strength of the joint. Three models—exponential, power law, and wear-out—were used to statistically analyze the fatigue life of the joints and to draw the stress–life (S–N) curves. The joints showed an infinite life of 25–35% of their quasi-static strength at 106 cycles. The joints surpassing 106 cycles were subsequently tested under quasi-static loading, showing no considerable reduction compared to their initial lap shear strength.

Poly(2,6-dimethyl-1,4-phenylene ether)/poly(phenylene sulfide)/styrenic block copolymer blends compatibilized with reactive polystyrene

Blends of poly(2,6-dimethyl-1,4-phenylene ether) (PPE) and poly(phenylene sulfide) (PPS) have shown potential as a new class of high-performance engineering plastics by reciprocally complementing the drawbacks of each component. However, improving their inherently poor toughness remains a challenge. Here, we report the design of PPE/PPS-based quaternary blends with increased impact strength without a significant loss of mechanical and flame-retardant properties. Introducing reactive polystyrene (RPS) with an oxazoline functional group as a compatibilizer improved the miscibility between the discrete PPE domain and continuous PPS matrix phases. The impact modifier styrene-ethylene-butadiene-styrene (SEBS) was compatibilized within the PPS matrix phase in the presence of RPS, enabling extraordinary impact strength. The tensile strength of the quaternary blends decreased slightly with increasing SEBS content, but the values exceeded the criteria for engineering plastic. All quaternary blends passed the V-0 grade in the UL-94 test because of the inherently excellent flame retardancy of the majority components.

Catalytic Reductive Cleavage of Poly(phenylene sulfide) Using a Hydrosilane

AbstractThe solvent-insoluble poly(phenylene sulfide) main chain was reductively cleaved by using triethylsilane as a hydrogen source under palladium/IcHex catalytic conditions. After the reaction, benzene and bis(triethylsilyl) sulfide as a sulfide source were formed efficiently. This method could be operated on a gram scale.

Biobased and mechanically stiff lignosulfonate/cationic-polyelectrolyte/sugar complexes with coexisting ionic and covalent crosslinks

We prepared moldable materials from lignosulfonate, an industrial lignin derivative, using a combination of ionic crosslinking between lignosulfonate and cationic polyelectrolytes and covalent crosslinking via the Maillard reaction. The mechanical properties of the lignosulfonate/cationic-polyelectrolyte/sugar complex at the optimal composition (stress at break: 55.1 MPa; Young’s modulus: 2791.8 MPa; strain at break: 3%) were comparable to those of poly(phenylene sulfide), which is used as a high-performance engineering plastic. In addition to the good mechanical properties, the lignosulfonate/cationic-polyelectrolyte/sugar complex was water-insoluble, in contrast with the high water solubility of the complex without the reducing sugar. Furthermore, the addition of a reducing sugar (fructose) to the complexes increased adhesion to a metal substrate. These improvements in the mechanical properties, water resistance, and adhesive strength of the lignosulfonate complex will expand the applications of lignosulfonate under high mechanical stress conditions and in water and biobased adhesives. Lignosulfonate is one of the major industrial products from wood. To utilize this compound as a moldable and strong material, we prepared a complex of lignosulfonate with cationic polyelectrolytes and reducing sugars. This complex contains two different crosslinking structures, i.e., ionic crosslinking between lignosulfonate and cationic polyelectrolytes and covalent crosslinking via the Maillard reaction of amino groups with reducing sugars. The coexisting of two different crosslinking greatly improved mechanical strength, Young’s modulus, water resistance, and adhesive strength compared with solely crosslinked complexes composed of the same ingredients.

Structural Transitions During Formation and Rehydration of Proton Conducting Polymeric Membranes.

Knowledge of the transitions occurring during the formation of ion-conducting polymer films and membranes is crucial to optimize material performances. The use of non-destructive scattering techniques that offer high spatio-temporal resolution is essential to investigating such structural transitions, especially when combined with complementary techniques probing at different time and spatial scales. Here, a simultaneous multi-technique study is performed on the membrane formation mechanism and the subsequent hydration of two ion-conducting polymers, the well-known commercial Nafion and a synthesized sulfonated poly(phenylene sulfide sulfone) (sPSS). The X-ray data distinguish the multi-stage processes occurring during drying. A sol-gel-membrane transition sequence is observed for both polymers. However, while Nafion membrane evolves from a micellar solution through the formation of a phase-separated gel, forming an oriented supported membrane, sPSS membrane evolves from a solution of dispersed polyelectrolyte chains via formation of an inhomogeneous gel, showing assembly and ionic phase separation only at the end of the drying process. Impedance spectroscopy data confirm the occurrence of the sol-gel transitions, while gel-membrane transitions are detected by optical reflectance data. The simultaneous multi-technique approach presented here can connect the nanoscale to the macroscopic behavior, unraveling information essential to optimize membrane formation of different ion-conducting polymers.

Process-structure–property relationships following thermo-oxidative exposure of powder bed fusion printed poly(phenylene sulfide)

Powder bed fusion (PBF) manufacturing with high-value polymers, like poly(phenylene sulfide) (PPS), are of current interest to many industries. Inconsistent part properties when reusing powder is one barrier preventing adoption of PBF. This manuscript compares changes in polymer structure and mechanical properties resulting from simulated application via thermo-oxidative exposure for new and re-used PBF printed PPS. Similar printed part density from both powder ages was achieved by compensating for differences between new and reused powders through adjusted print settings. Thermomechanical properties were observed to change less for parts made with re-used PPS powder compared with as-received powder following thermo-oxidative exposure.