The mechanical and tribological properties of MAH-grafted HDPE filled SiO 2 /PMMA composite

Polyoxymethylene (POM)-based composites with polytetrafluoroethylene (PTFE) filler and silicone gum have been prepared by melt extrusion to enhance the wear resistance and friction lubrication of POM without compromising the other desired properties such as modulus, toughness/impact strength, notch insensitivity, and thermal stability. The compounded material was injection molded to prepare test specimens, and their physico-mechanical properties were evaluated. In addition, thermal and tribological characteristics of the composites were also studied. The addition of silicone into POM/PTFE composites could enhance the formation of stable transfer film on the mating surface during sliding contact, thus improving the friction and wear performance, as silicone forms synergistic mixture with PTFE. It was found that the tensile, flexural, and notched impact strength remained almost constant for all the formulations. The use of PTFE improved the unnotched impact strength (from 35.5 to 42.9 kJ m−2). The toughening effect can be attributed to the dissipation of impact energy through soft PTFE and ductile silicone phase. Differential scanning calorimeter results revealed that there are no negative effects on POM crystallinity due to the presence of PTFE and silicone. The wear behavior of composites has been investigated under dry sliding conditions at different normal loads and sliding velocities at room temperature. The POM/PTFE/silicone (90/8/2 wt/wt%) formulation exhibits better wear-resistant behavior in the present study.

Section: Resultsmentioning

confidence: 68%

Physico-mechanical, thermal, and tribological studies of polytetrafluoroethylene-filled polyoxymethylene/silicone composites

Gowda¹,

Hemavathi²,

Srinivas³

et al. 2020

“…Also, their alloys consist of enhanced benefits of low density, simplicity of manufacturing, significant shock absorption capacity, wear resistance and high vibration self-lubrication. [6][7][8] Many studies have been conducted to enhance the polymer characteristics of UHMWPE since its debut in the 1960s as a preferred material for implant-bearing components. Because of its clinical performance over the past few decades, UHMWPE is commonly used for artificial joints.…”

Section: Introductionmentioning

confidence: 99%

Development of reduced Graphene oxide modified Ultrahigh molecular weight polyethylene (rGO/UHMWPE) based Nanocomposites for Biomedical Applications

Singh

Verma

2022

Ultrahigh molecular weight polyethylene (UHMWPE) are widely used as a biomaterial for manufacturing of prostheses, implants and other biomedical components with complex geometry and shapes. Continuous loading of these components subject to heavy stress and deformation resistance should have enhanced mechanical and chemical properties. This paper aims to improve the mechanical and thermal aspects of the conventional UHMWPE by supplementing reduced Graphene oxide (rGO) in varying weight percentages to develop polymer bio nanocomposite samples. The effect of green synthesized GO nanoparticles in the UHMWPE polymer was investigated for biomedical application. The rGO was distributed in a UHMWPE matrix using a unique and optimized technique to create high-performance nanocomposites. The proposed UHMWPE filled with different loading (0, 0.5, 1.0,1.5, 2.0, and 3.0 wt.%) of rGO was produced by Ultrasonication in an acetone medium. The findings suggest that evenly distributed rGO layers were present throughout the polymer matrix. This, in turn, indicates a good connection between the fillers and matrix by Scanning electron microscopy (SEM) and Energy Dispersive X-Ray Analysis (EDAX), resulting in better composite capabilities. The layers of rGO-aided lamellar arrangements and microfibers between the crystals were observed in the results. The Microhardness of the bio nanocomposite (1 Wt.% rGO/UHMWPE) with 1wt.% rGO in the UHMWPE matrix increased by 2.8% compared to an unfilled polymer. At the same rGO concentration, the bio nanocomposite had a crystallization degree of 46.96%. To achieve optimal performance, rGO content of 1wt.% was added to the sample, which is ideal in many situations where good mechanical and thermal qualities are required during operation. The outcomes reveal that the rGO supplement primarily boosts the thermo-mechanical performances of the modified bio-nano composites for orthopedic products.

“…PMMA has several desirable properties, including exceptional optical clarity, good weatherability, high strength, biocompatibility, and excellent dimensional stability. 12,13 It can also be processed at the micro-and nanoscale by lithography and replication technologies. Its unique properties, like good mechanical strength, excellent optical transparency, and its ability to get molded in any form, have led to enormous possibilities.…”

Section: Introductionmentioning

confidence: 99%

The interlaminar shear strength and impact performance of polytetrafluoroethylene fiber-reinforced polymethyl methacrylate composites filled with silicon dioxide

Zhang

2014

The interlaminar shear strength (ILSS) of polytetrafluoroethylene (PTFE) fiber-reinforced polymethyl methacrylate (PMMA) composites enhanced by filled silicon dioxide (SiO 2 ) is studied. The PMMA blends were prepared by combining the techniques of high-speed mechanical stirring. Experimental results showed that ILSS and impact properties of PMMA composites were improved. The largest improvement in ILSS and impact strength were obtained with 7 vol % loading of SiO 2 . ILSS and impact strength were improved by 15 and 50%, respectively, compared with the composite without SiO 2 . The fracture and surface morphologies of the composite specimens were characterized using scanning electron microscopy. This PTFE fiber-reinforced composite can be applied to bioengineering and fabrics.