Comparative study on the mechanical, tribological, and thermal properties of POM composites filled with different PTFE

In this study, two different types of polytetrafluoroethylene (PTFE) fillers (i.e. fibrillar and particulate PTFE) were utilized to improve the tribological properties of polyoxymethylene (POM). POM/PTFE composites with various filler contents were tested on a commercial block-on-ring tester. To further probe the tribological properties of POM/PTFE composites under severe sliding conditions, a homemade pin-on-disc tester was employed. Results showed that the lowest coefficient of friction and wear rate are obtained from PTFE particle–filled POM composites at 20 wt%, which is attributed to the formation of uniform transfer film at the sliding interface thanks to the well distribution of PTFE particles. The mass wear rate of POM/PTFE fiber composites is lower than that of PTFE particle–containing counterparts due to the better load transfer of high aspect ratio fibers. The tensile properties of POM/PTFE composites deteriorate with the addition of PTFE fillers; however, the impact strength is significantly enhanced for PTFE fiber filled POM composites. Moreover, both the melting and crystallization properties of POM are affected by the morphology of PTFE fillers and filler concentration, as characterized by differential scanning calorimetry analysis.

Abrasive wear performance of multi-layer interwoven polyester fiber & PTFE particle reinforced polyester composite

This study aims to systematically investigate the abrasive wear performance of composite material with multi-layer polyester fiber interweaving and PTFE particle reinforced polyester matrix under dry friction conditions. Abrasive wear performance experimentally investigated by applying the block on ring test method depending on the direction of fiber weaving. The test material exposed to pure water, mineral oil, HNO3, and NH3 for 1, 2, 3, 4 weeks. The sliding distances and test durations were determined to be 2.26, 4.52, 6.78 and 9.04 km, 1, 2, 3 and 4 hours respectively. The best wear resistance was obtained in the perpendicular direction to the fiber reinforcement. While HNO3 and NH3 environments significantly decrease the wear resistance, oil and pure water environments increase the wear resistance by lubricant effect.

Thermal Properties of Thermoplastic Rubber (TPR) Reinforced with Polytetrafluroethylene (PTFE) Particle Polymer Composite

Thermal exploration of thermoplastic rubber (TPR) and its composites has been playing a vital role in polymer industries during the past few decades. TPR is a compound which shows a thermoplastic character over its melting temperature and has elastomeric conduct within its design temperature range without cross-linking during fabrication. PTFE particles have a high temperature application and discover the best filler particle in the composite. Samples of 100% TPR and 10% PTFE by weight, 20% PTFE by weight mixed specimens with TPR were prepared by utilizing Injection molding strategies. Test results demonstrate PTFE filler included composites displaying high thermal conductivities.

Thermal Performance of Acrylonitrile Butadiene Styrene (ABS) Copolymer Blended with PTFE Particle/Polymer Composite

Acrylonitrile Butadiene Styrene (ABS) polymer and Polytetrafluroethylene (PTFE) polymer has different properties individually. In this work ABS is used as matrix and PTFE is used as particle reinforcement. ABS is a copolymer containing butadiene, styrene and acrylonitrile. This work is to focus about the thermal property of ABS copolymer by adding PTFE as particle in polymer composites. From the analysis PTFE fit into a perfect particle reinforcement material for a broad assortment of utilizations. The samples is prepared with 100% ABS and 10% PTFE by weight, 20% PTFE is added to ABS and fabricated with Injection molding process. The addition of PTFE to ABS has improved on thermal properties. Experiment results shows that PTFE filler added composites exhibited high thermal conductivities and good coefficient of linear thermal expansion when compared with pure ABS copolymer.

Effect of PTFE Particle Size on Superhydrophobic Coating for Supercooled Water Prevention

Polytetrafluoroethylene (PTFE) chemically repels water droplets due to the nature of fluorine substituents. This paper presents an experimental study on the impact of PTFE particle size and temperature on the hydrophobicity of a surface. The present study analyzes hydrophobicity due to both the chemical properties of PTFE and the microstructure created by PTFE particles. Herein, studies of the contact angle and the sliding angle of these surfaces are described in supercooled-water conditions ranging from −10 to 0 °C. From the equations governing the surface tension and sliding angle of a droplet on a superhydrophobic surface, it is found that particle size has a much greater effect on hydrophobicity than temperature. An increase in the PTFE particle size greatly reduces the sliding angle, which indicates a lower amount of energy required to remove the droplet from the surface.

Experimental Study of PTFE Powder Size Impact to Mg/PTFE Pyrotechnic Composition

To discover the polytetrafluoroethylene (PTFE) powder size impact to Mg/PTFE pyrotechnic composition, hot compatibility of various particle sizes of PTFE powder with spherical superfine Mg powder was studied. Safety performance of Mg/PTFE pyrotechnic composition was also researched by parameters of friction and impact sensitivity. Burning temperature and velocity were recorded and analysed. The result shows that the Mg/PTFE exothermic temperature peak floats =0.8~2.2°C, apparent activation energy alter ratio (AAEAR) =12.5%~17.8%, ignition probability due to friction sensitivity =0.32~0.48 and to impact sensitivity =0. It indicates that PTFE powder size will not inflect the safety of Mg/PTFE composition, which burns more stable with PTFE size great than 400μm. Once mass combustion velocity 2.09~3.87 g•cm-2•s-1 and linearcombustion velocity 5.02~8.13 mm•s-1, the combustion velocity will increase much by following with PTFE particle sizes decrease.

Performance of Intermediate Temperature Fuel Cells with Proton Conducting Electrolytes Synthesized with Diammonium Hydrogen Phosphate (1)

The (ZrO2-1.6P2O5)-PTFE composite electrolytes have been prepared by mixing PTFE powders with different particle sizes and the shell-core-type ZrO2-1.6P2O5electrolyte, synthesized by solid state reaction with diammonium hydrogen phosphate, to improve the mechanical strength of the electrolyte. The H2gas permeability decreased and the cell performances improved with decreasing PTFE-particle size. The aging at 0.4 V above 443 K enhanced the ITFC performance owing to the penetration of the electrolyte to the carbon paper. The maximum output power enhanced by 63% after 15 h of aging at 573 K.