Ultra-high Molecular Weight Polyethylene Research Articles

Ethylene Polymerization over Metal-Organic Framework-Supported Zirconocene Complexes.

Metallocene immobilization onto a solid support helps to overcome the drawbacks of homogeneous metallocene complexes in the catalytic olefin polymerization. In this study, valuable insights have been obtained into the effects of pore size, linker composition, and surface groups of metal-organic frameworks (MOFs) on their role as support materials for metallocene-based ethylene polymerization catalysis. Three distinct Zn-based metal-organic frameworks (MOFs), namely, MOF-5, IRMOF-3, and ZIF-8, with different linkers have been activated with methylaluminoxane (MAO) and zirconocene complexes, followed by materials characterization and testing for ethylene polymerization. Characterization has been performed by multiple analytical tools, including X-ray diffraction (XRD), scanning electron microscopy (SEM), gel permeation chromatography (GPC), differential scanning calorimetry (DSC), and CO Fourier transform infrared (FT-IR) spectroscopy. It was found that the interactions between MOFs, MAO, and the zirconocene complex not only lead to both catalyst activation and deactivation but also result in the creation of multiple active sites. By alteration of the MOF support, it is possible to obtain polyethylene with different properties. Notably, ultrahigh molecular weight polyethylene (UHMWPE, M W = 5.34 × 106) was obtained using IRMOF-3 as support. This study reveals the potential of MOF materials as tunable porous supports for metallocene catalysts active in ethylene polymerization.

Supercritical CO2-Assisted Electroless Plating of Ultrahigh-Molecular-Weight Polyethylene Filaments for Weavable Device Application

This study reports on the use of supercritical CO2 (scCO2) for the metallization of ultrahigh-molecular-weight polyethylene (UHMW-PE) filaments, which are used as functional components in weavable devices. UHMW-PE is well known for its chemical and impact resistance, making it suitable for use in bulletproof clothing and shields. However, its chemical resistance poses a challenge for metallization. By utilizing scCO2 as the solvent in the catalyzation process, a uniform and defect-free layer of Ni-P is successfully deposited on the UHMW-PE filaments. The deposition rate of Ni-P is enhanced at higher temperatures during the scCO2 catalyzation. Importantly, the durability of the Ni-P-metalized UHMW-PE filaments is improved when the scCO2 catalyzation is carried out at 120 °C, as evidenced by minimal changes in electrical resistivity after a rolling test.

Sensitivity, robustness, and reproducibility of U-shaped delamination test for evaluation of candidate ultra-high molecular weight polyethylene materials for joint replacements.

The delamination of ultra-high molecular weight polyethylene (UHMWPE) in artificial joints is a major cause limiting the long-term clinical results of arthroplasty. However, the conventional test method using simple reciprocation to evaluate the delamination resistance of UHMWPE materials has insufficient detection sensitivity. To reproduce delamination, the unconformity contact must be maintained throughout the test so that the maximum stress is generated below the surface. Therefore, a test method that applies a U-shaped motion comprising two long-linear and one short linear sliding motion was developed. The sensitivity, robustness, and reproducibility of the U-shaped delamination test were investigated and compared with the traditional test method. The traditional test method could reproduce delamination only in materials that had degraded considerably, whereas the U-shaped delamination test could reproduce delamination in a wide range of materials, demonstrating its superior sensitivity. Additionally, using a higher load helped accelerate the test without affecting the test results. The optimal length of the short linear sliding motion was confirmed to be 1 mm. Finally, the inter-laboratory reproducibility of the U-shaped delamination test was confirmed using the round-robin test. The U-shaped delamination test demonstrates high sensitivity, robustness, and reproducibility and contributes to the selection and development of UHMWPE materials and artificial joints with a lower risk of delamination.

Engineered Niobium Carbide MXenzyme-Integrated Self-Adaptive Coatings Inhibiting Periprosthetic Osteolysis by Orchestrating Osteogenesis-Osteoclastogenesis Balance.

Periprosthetic osteolysis induced by the ultrahigh-molecular-weight polyethylene (UHMWPE) wear particles is a major complication associated with the sustained service of artificial joint prostheses and often necessitates revision surgery. Therefore, a smart implant with direct prevention and repair abilities is urgently developed to avoid painful revision surgery. Herein, we fabricate a phosphatidylserine- and polyethylenimine-engineered niobium carbide (Nb2C) MXenzyme-coated micro/nanostructured titanium implant (PPN@MNTi) that inhibits UHMWPE particle-induced periprosthetic osteolysis. The specific mechanism by which PPN@MNTi operates involves the bioresponsive release of nanosheets from the MNTi substrate within an osteolysis microenvironment, initiated by the cleavage of a thioketal-dopamine molecule sensitive to reactive oxygen species (ROS). Subsequently, functionalized Nb2C MXenzyme could target macrophages and escape from lysosomes, effectively scavenging intracellular ROS through its antioxidant nanozyme-mimicking activities. This further achieves the suppression of osteoclastogenesis by inhibiting NF-κB/MAPK and autophagy signaling pathways. Simultaneously, based on the synergistic effect of MXenzyme-integrated coatings and micro/nanostructured topography, the designed implant promotes the osteogenic differentiation of bone mesenchymal stem cells to regulate bone homeostasis, further achieving advanced osseointegration and alleviable periprosthetic osteolysis in vivo. This study provides a precise prevention and repair strategy of periprosthetic osteolysis, offering a paradigm for the development of smart orthopedic implants.

Feasibility of Repairing Concrete with Ultra-High Molecular Weight Polyethylene Fiber Cloth: A Comprehensive Literature Review

This review explores the use of Ultra-High Molecular Weight Polyethylene (UHMWPE) fiber cloth as an innovative solution for the repair and reinforcement of concrete structures. UHMWPE is a polymer formed from a very large number of repeated ethylene (C2H4) units with higher molecular weight and long-chain crystallization than normal high-density polyethylene. With its superior tensile strength, elongation, and energy absorption capabilities, UHMWPE emerges as a promising alternative to traditional reinforcement materials like glass and carbon fibers. The paper reviews existing literature on fiber-reinforced polymer (FRP) applications in concrete repair in general, highlighting the unique benefits and potential of UHMWPE fiber cloth compared to other commonly used methods of strengthening concrete structures, such as enlarging concrete sections, near-surface embedded reinforcement, and externally bonded steel plate or other FRPs. Despite the scarcity of experimental data on UHMWPE for concrete repair, this review underscores its feasibility and calls for further research to fully harness its capabilities in civil engineering applications.

Design and Scalable Fast Fabrication of Biaxial Fabric Pouch Motors for Soft Robotic Artificial Muscle Applications

Soft pouch motors, engineered to mimic the natural movements of skeletal muscles, play a crucial role in advancing robotics and exoskeleton development. However, the fabrication techniques often involve multistage processes; they lack soft sensing capabilities and are sensitive to cutting and damage. This work introduces a new textile‐based pouch motors with the capacity for biaxial actuation and capacitive sensory functions, achieved through the application of computerized knitting technology using ultrahigh molecular weight polyethylene yarn (Spectra) and conductive silver yarns. This method enables the rapid and scalable mass fabrication of robust pouch motors. The resulting pouch motors exhibit maximum lifting capacity of 10 kg, maximum contraction of 53.3% along the y‐axis, and transverse extension of 41.18% along the x‐axis at 50 kPa pressure. Finite element analysis closely matches the experimental data. The capacitance signals in relation to contraction motion are well suited for detecting air pressure levels and hold promise for applications requiring robotic control. Notably, it effectively elevates an ankle joint simulator at a 20° angle, highlighting its potential for applications such assisting individuals with foot drop. This study presents a practical demonstration of the soft ankle exosuit designed to provide lifting support for individuals facing this mobility challenge.

Ballistic response mechanism and resistance-driven evaluation method of UHMWPE composite

The use of ultra-high molecular weight polyethylene (UHMWPE) composite in the design of lightweight protective equipment, has gained a lot of interest. However, there is an urgent need to understand the ballistic response mechanism and theoretical prediction model of performance. This paper explores the ballistic response mechanism of UHMWPE composite through experimental and simulation analyses. Then, a resistance-driven modeling method was proposed to establish a theoretical model for predicting the bulletproof performance. The ballistic response mechanism of UHMWPE composite encompassed three fundamental modes: local response, structural response, and coupled response. The occurrence ratio of these fundamental response modes during impact was dependent on the projectile velocity and laminate thickness. The bulletproof performance of laminate under different response modes was assessed based on the penetration depth of the projectile, the bulging height on the rear face of the laminate, the thickness of remaining sub-laminate, and residual velocity of the projectile. The absolute deviations of bulletproof performance indicator between theoretical value and experimental value were well within 11.13%, demonstrating that the established evaluation model possessed high degree of prediction accuracy.

Oxidation and Damage Mechanisms of Second-Generation Highly Cross-Linked Polyethylene Tibial Inserts

BackgroundAfter clinical introduction in 2005, sequentially annealed, highly cross-linked polyethylene (SA HXLPE) was studied for retrievals with short implantation times; however, long-term follow-ups are lacking. The objective of this study was to examine and compare the revision reasons, damage mechanisms, and oxidation indices of SA HXLPE and conventional gamma inert–sterilized (Gamma Inert) ultra-high-molecular-weight polyethylene tibial inserts implanted for >5 years. MethodsThere were 74 total knee arthroplasty tibial inserts (46 SA HXLPEs, 28 Gamma Inerts) implanted for >5 years (mean 7 ± 2 years) retrieved as part of a multicenter retrieval program. Cruciate-retaining implants comprised 44% of the SA HXLPEs and 14% of the Gamma Inerts. Patient factors and revision reasons were collected from revision operating notes. A semiquantitative scoring method was used to assess surface damage mechanisms. Oxidation was measured using Fourier transform infrared microscopy according to American Society for Testing and Materials 2102. Differences between cohorts were assessed with Mann–Whitney U-tests. ResultsLoosening (Gamma Inert: 17 of 28, SA HXLPE: 15 of 46) and instability (Gamma Inert: 6 of 28, SA HXLPE: 15 of 46) were the most common revision reasons for both cohorts. The most prevalent surface damage mechanisms were burnishing, pitting, and scratching, with burnishing of the condyles being higher in Gamma Inert components (P = .022). Mean oxidation was higher in the SA HXLPE inserts at the articulating surface (P = .002) and anterior-posterior faces (P = .023). No difference was observed at the backside surface (P = .060). ConclusionsRevision reasons and surface damage mechanisms were comparable in the Gamma Inert and SA cohorts. Further studies are needed to continue to assess the in vivo damage and clinical relevance, if any, of oxidation in SA HXLPE over longer implantation times, particularly for implants implanted for more than 10 years.

Composite Materials Based on Al2O3 with a Two-Layer Polymer Coating of Ultra-High Molecular Weight Polyethylene and Polyethylene: Synthesis, Properties, and Processing by 3D Printing by Selective Laser Sintering

Composite Materials Based on Al2O3 with a Two-Layer Polymer Coating of Ultra-High Molecular Weight Polyethylene and Polyethylene: Synthesis, Properties, and Processing by 3D Printing by Selective Laser Sintering

Thermally induced phase separation of UHMWPE mixture with dioctyl adipate: Competition of liquid–liquid phase separation and polymer crystallization

The thermal behavior of ultra-high molecular weight polyethylene (UHMWPE) with dioctyl adipate (DOA) was investigated by the differential scanning calorimetry (DSC) method. Capillary-porous bodies were obtained via thermally induced phase separation of DOA mixtures with polyethylenes of different molecular weight at different cooling rates. Analysis of the morphology of the prepared porous bodies together with DSC data and results of cloud point estimation revealed an unexpected effect of a cooling rate on the type of phase separation occurring in the mixture during its cooling from homogeneous state. Particularly it was shown that increase in the cooling rate reduces the probability of realization of liquid – liquid phase separation in the mixture. It was argued that such behavior, different from the standard semicrystalline polymers, is a result of kinetic hindrance of liquid – liquid phase separation in mixtures containing a polymer with such a high molecular weight.

Temperature dependent cut‐resistance properties of ultra‐high molecular weight polyethylene based knitted textiles

AbstractThe increasing awareness of safety standards for personal protective equipment in various industries and everyday life has significantly increased the demand for effective cut‐resistance clothing to prevent injuries. Ultra‐high molecular weight polyethylene (UHMWPE), renowned for its strength, is predominantly used to produce cut‐protective clothing for sectors such as automotive, manufacturing, glass, and metal. These cut‐resistance clothing are often exposed to harsh workplace conditions, including elevated temperatures, which can compromise their structural integrity and diminish their cut‐protection efficacy. The present work investigates the effect of temperature on the cut‐resistance performance of core‐spun UHMWPE yarns integrated with stainless‐steel and glass filament‐based knitted fabrics. Cut‐performance was assessed across industrial work handling temperatures ranging from 30 to 75°C. Furthermore, thermal cut performance was analyzed by structural characterization and surface morphology of the samples. The results revealed a general decline in cut performance with increasing temperature for all samples, with stainless steel‐reinforced UHMWPE fabrics experiencing the most pronounced reduction % compared with their glass fiber‐reinforced and 100% UHMWPE counterparts. These results are substantiated by analyses of surface temperature distribution profiles and x‐ray diffraction outcomes. This study benefits industry workers, guiding them in selecting effective protective clothing for varied thermal conditions.

Effect of Hot-Pressing Process on Mechanical Properties of UHMWPE Fiber Non-Woven Fabrics.

In order to investigate the influence of a hot-pressing process on the mechanical properties of ultra-high molecular weight polyethylene (UHMWPE) fiber non-woven fabrics with stretch and in-plane shear, UHMWPE non-woven fabric samples were prepared by adjusting the temperature, time, and pressure of the hot-pressing process, and mechanical property tests were carried out so as to clarify the influence of the hot-pressing process on the mechanical properties of the samples. The results show that the hot-pressing process mainly affects the silk-glue bonding strength of the samples; in the test range, with the increase in hot-pressing temperature and time, the tensile strength and in-plane shear strength of the samples increase and then decrease, and the best mechanical properties are obtained at 130 °C and 7 min of hot pressing, respectively; at 130 °C, the in-plane shear strength is 39.94 MPa and the tensile strength is 595.43 MPa; at 7 min, the in-plane shear strength is 63.0 MPa and the tensile strength is 643.30 MPa; with the increase in the hot-pressing pressure, the in-plane shear strength of the samples increases and then decreases, and the highest is 52.60 MPa, achieved at 8 MPa; in the range of 5-8 MPa, the tensile strength of the specimens did not change significantly, and increased significantly at 9 MPa, reaching a maximum strength of 674.55 MPa.

Multiscale Texture Features to Enhance Lubricant Film Thickness for Prosthetic Hip Implant Bearing Surfaces

The longevity of prosthetic hip implants is significantly influenced by wear. Surface textures of various length scales can reduce the friction coefficient and wear of lubricated bearing surfaces. The optimization of multiscale texture parameters, aimed at maximizing lubricant film thickness, was achieved through hydrodynamic lubrication simulations that solve the Reynolds equation with a mass-conserving cavitation model under various operating conditions. The outcomes indicate that adding “interstitial” texture features to a pattern of microscale texture features can further increase the lubricant film thickness. Additionally, the lubricant film thickness increases as the interstitial texture feature aspect ratio and texture density decrease. Pin-on-disc experiments align with simulation findings, demonstrating that multiscale texturing with ultra-fast laser ablation on Ti6Al4V discs significantly improves wettability and reduces the friction coefficient of ultra-high molecular weight polyethylene pins when compared to untextured and microscale textured surfaces. The multiscale surface texturing also changes the evident wear mechanisms on the pins, reducing the incidence of abrasive scratches and adhesive wear compared to both untextured and just microscale textured surfaces.

Tribological evaluation of thermoplastic polyurethane-based bearing materials under water lubrication: Effect of load, sliding speed, and temperature

Polymers are widely used in bearing applications. In the case of water-lubricated stern tube bearings, thermoplastic polyurethane (TPU)-based composites are used due to their excellent wear resistance, corrosion resistance, and tunable mechanical properties. Their tribological performance, however, depends on operating conditions. In this work, TPU was blended with carbon fiber, graphene platelet, and ultra-high molecular weight polyethylene (UHMWPE). Friction tests of TPU based-composites against copper countersurface were carried out in water to mimic the actual operating conditions of the bearing. Most of the resulting contacts were in the boundary lubrication regime, in which friction was attributed to both contact mechanics of asperities as well as water lubrication. Our results show that the viscoelasticity of TPU has a considerable impact on its tribological performance. Water lubrication at 50 °C promotes the softening of polymer surface material during sliding, resulting in higher fluctuation in the coefficient of friction and wear loss. This is attributed to the reduced thermomechanical properties. In addition, Schallamach waviness is observed on worn surface. The tribological properties of TPU are significantly improved by the inclusion of carbon fiber, graphene platelet, and UHMWPE. The formation of graphene transfer-layers and UHMWPE transfer film reduces friction and wear loss, while the inclusion of carbon fiber enhances wear resistance due to improved mechanical properties and load bearing capacity.

Enhancing the self-healing performance of engineered cementitious composites in harsh environment through cementitious matrix optimization and crack width controlling

The fragile cementitious materials can be easily cracked under service in the harsh environment, which can reduce the loading capacity of concrete structures and its expected service life. The self-curing ability of cementitious materials is thus essential for the resilience of the concrete structures in harsh environments. The purpose of the study is to enhance the self-healing ability of Engineered Cementitious Composites (ECC) in harsh environment though cementitious matrix optimization and crack width controlling. The cementitious matrix containing cement, silica fume, and fly ash is optimized based on the Simple Centroid Method. The Ultra-high Molecular Weight Polyethylene (UHMWPE) fibers have been selected as reinforcing materials due to their superior mechanical performance. The results show that the compressive strength of the ECC samples generally increases with the silica fume content, and the tensile strength rises with both the silica fume and cement content. Meanwhile, the ultimate tensile strain of the ECC samples increases and declines with the fly ash and silica fume content, respectively. The self-repairing properties of the pre-damaged ECC specimens with 5 % strain are examined through exposure in the simulated harsh environment. It is found that the exposure to the groundwater environment can improve the self-curing ability of the pre-damaged ECC specimens, while the self-curing ability can be deteriorated under exposure to the marine environment. Furthermore, the crack sealing and strength recovery ability of cementitious materials can be enhanced with higher fly ash content and lower silica fume content. Finally, the self-curing mechanism of the ECC samples is analyzed by means of the phase and microstructure analysis. Exposure to groundwater environments can promote the generation of the C–S–H gel and calcium carbonate in the self-curing product, and thus enhance the self-healing efficiency. This study can contribute the resilience enhancement of the concrete structure in harsh environments.

Ethylene Polymerizations Catalyzed by Fluorinated "Sandwich" Diimine-Nickel and Palladium Complexes.

Nickel and palladium complexes bearing "sandwich" diimine ligands with perfluorinated aryl caps have been synthesized, characterized, and explored in ethylene polymerization reactions. The X-ray crystallographic analysis of the precatalysts 16 and 6b shows differences from their nonfluorinated analogues 17 and 19, with the perfluorinated aryl caps centered precisely over the nickel and palladium centers, which results in higher buried volumes of the metal centers relative to the nonfluorinated analogues. The sandwich diimine-palladium complexes 5a and 5b containing perfluorinated aryl caps polymerize ethylene in a controlled fashion with activities that are substantially increased compared with their nonfluorinated analogues. Migratory insertion rates in relevant methyl ethylene complexes agree with the activities exhibited in bulk polymerization experiments. DFT studies suggest that facility of ethylene rotation from its preferred orientation perpendicular to the Pd-alkyl bond into a parallel in-plane conformation contributes to the higher polymerization activity for 5b relative to 18a. For these palladium systems, polymer molecular weights can be controlled via hydrogen addition (hydrogenolysis), which is unusual for late-transition-metal-catalyzed olefin polymerizations with no catalyst deactivation occurring. Sandwich diimine-nickel complexes 6a and 6b with perfluorinated aryl caps show ethylene polymerization activities that are about half of those of classical tetraisopropyl-substituted catalyst 2 but again are more active than the analogous nonfluorinated sandwich complexes. Ethylene polymerizations exhibit living behavior, and branched ultrahigh-molecular-weight polyethylenes (UHMWPEs) with very low-molecular-weight distributions (less than 1.1) are obtained. The activated nickel catalysts are stable in the absence of monomer and show good long-term stability at 25 °C.

Mechanical behavior of STF impregnation and anti-impact performances of Kevlar and UHMPWEF fabric impregnations

STF-impregnated Kevlar and ultra-high molecular weight polyethylene (UHMWPEF) fabric-impregnated bodies were prepared by using mass fraction of 34 % SiO2 with a particle size of 100 nm and PEG400 as dispersion and dispersant, respectively. When two kinds of fiber fabrics were impregnated by STF, the tensile, single fiber pull-out and single fiber tensile loads of Kevlar fabric-impregnated increased 26.63 %, 155.55 %, and 98.64 %, respectively. However, the tensile load, monofilament pull-out load and monofilament tensile load of the UHMWPEF fabric-impregnated body increased 100.14 %, 729.03 % and 51.61 %, respectively. Kevlar fiber fabric impregnated by ultrasonic vibration and smearing STF absorbs more steel projectile’s kinetic energies of 52.3 % and 27.43 % than that of the original fiber fabric, respectively. UHMPWEF fabric impregnated by using ultrasonic vibration and smearing increased 65.56 % and 47.73 % than the original fabric absorbing steel projectile’s kinetic energy. Based on the Scanning Electron Microscope (SEM) observation of the fiber fabric surface, it was found that the connection between the fibers was significantly strengthened after the STF impregnation treatment. When the fabric was subjected to impact load, STF played an important role in transmitting load and increasing friction.

The impact of boron carbide in soft and hard body armor: A comprehensive evaluation on Kevlar and UHMWPE fabrics

AbstractIn this research, an investigation was conducted to ascertain the impact of boron carbide (B4C) microparticles on soft and hard armor configurations, utilizing two distinct high‐performance fabrics namely, Kevlar and Ultra‐high Molecular Weight Polyethylene (UHMWPE), also this work discerned the optimal fabric for protection against dagger attacks and 9 mm full metal jacket (FMJ) projectiles. Initially, rheological tests on four shear thickening fluid (STF) samples revealed that 70% of nano‐silicate (SiO2) content was the optimal ratio. Besides, scanning electronic microscope (SEM) tests showed that B4C affected the nano‐silicate dispersion. Hence, the use of STF as a matrix, led to complete protection in low‐velocity stab test and behavior improvement when subjected to NIJ ballistic test for both fabric types. On the other hand, the dynamic mechanical analysis (DMA) of the thermosetting epoxy resin‐based composites reinforced by B4C indicated that the 10% ratio offered maximum rigidity, resulting in improved ballistic performance. This study revealed that Kevlar fabrics exhibit superior behavior in soft protection, while UHMWPE hard composite display further rigidity against high‐velocity impacts. Overall, this work contributes novel insights into the efficiency of B4C integration within soft and hard armor configurations using two ballistic fabrics, highlighting their performance characteristics in ballistic shielding.Highlights Investigation of B4C microparticles: The research examines the impact of B4C microparticles on soft and hard armor configurations. High‐performance fabrics: Kevlar and UHMWPE uses. The use of STF as a matrix for soft and thermosetting epoxy resin for hard armor: enhanced composite performance. Low‐velocity and high‐velocity impact tests investigations; microparticles B4C incorporation: superior mechanical characteristics. Remarkable energy absorption: promising shielding uses.

Comparison of the physico-chemical behavior of two prepregs used for body armor

The development of ultra-high molecular weight polyethylene fibers has resulted in continued improvement in ballistic protection, along with reduced weight in body armors. Prepregs from newly developed fibers are constantly available, although prepregs from older brands still remain on the market. In this work, the physicochemical properties of two successive generations of pre-impregnated materials are characterized to compare the two materials in the as-received condition and also after be consolidated in a ballistic plate. The results showed that fibers from the newer brand have a smaller diameter and greater tensile strength. This is an important result because the tensile strength of fibers is one of the variables that influence the ballistic performance of body armors. The smaller diameter of these fibers was associated with a greater degree of stretching during their manufacture, as revealed by the presence of two melting peaks in the DSC analysis.

Characterization of surface and bulk properties of α-Tocopherol blended and γ irradiated UHMWPE sandwich nanocomposites

In the present study, an unconventional approach in compression molding is chosen to fabricate Ultra High Molecular Weight Polyethylene (UHMWPE) sandwich composites with Graphene (Gr) and Nano-diamond (ND) as fillers. A unique comparison is done between the surface and bulk properties of UHMWPE nano-composites and UHMWPE sandwich composites. Influence of gamma irradiation at doses of 50, 100 kGy doses and vitamin E (vit-E) on crystal structure, mechanical, thermal and tribological characteristics of UHMWPE composites were studied through x-ray diffraction (XRD), raman spectroscopy, dynamic mechanical analysis (DMA), rheology, differential scanning calorimetry (DSC), tensile, nano-indentation and wear characterization techniques. Fracture regions and surface wear of the samples were analysed through scanning electron microscopy (SEM) to understand the dispersion behavior of fillers in matrix. The concentration of vit-E content in UHMWPE greatly influenced the crosslinks and surface properties in gamma irradiated composites. Gamma irradiation have shown significant improvement in crystallinity, viscous behavior and bulk properties of UHMWPE composites. Irradiated UHMWPE nano-composites have shown better tensile results when compared with sandwich composites, with 22 % increase in young's modulus and 16 % increase in yield stress. Wear rate has been reduced by 25 % for irradiated sandwich UHMWPE composites when compared with UHMWPE nano-composites.