Poly Methyl Methacrylate Composites Research Articles

Antibiotic Release and Mechanical Performance of Polymethylmethacrylate (PMMA) Bone Cement: Findings from In-vitro Studies

Using Polymethylmethacrylate (PMMA) bone cement is widespread in orthopedic surgeries for implant fixation and as a carrier for antibiotic delivery to prevent and treat infections. This review comprehensively evaluates in-vitro studies investigating the antibiotic elution profiles and mechanical properties of PMMA bone cement. We explore the kinetics of antibiotic release, factors influencing elution efficiency and the impact of various antibiotics on the mechanical properties of PMMA composites. At the same time, we examine how the inclusion of antibiotics affects the mechanical integrity of PMMA, including parameters such as compressive strength, tensile strength and fatigue resistance. Through a detailed analysis of these studies, this review aims to provide insights into optimizing PMMA bone cement formulations for enhanced therapeutic efficacy and structural performance. Using Polymethylmethacrylate (PMMA) bone cement is widespread in orthopedic surgeries for implant fixation and as a carrier for antibiotic delivery to prevent and treat infections. This review comprehensively evaluates in-vitro studies investigating the antibiotic elution profiles and mechanical properties of PMMA bone cement. We explore the kinetics of antibiotic release, factors influencing elution efficiency and the impact of various antibiotics on the mechanical properties of PMMA composites. At the same time, we examine how the inclusion of antibiotics affects the mechanical integrity of PMMA, including parameters such as compressive strength, tensile strength and fatigue resistance. Through a detailed analysis of these studies, this review aims to provide insights into optimizing PMMA bone cement formulations for enhanced therapeutic efficacy and structural performance.

Sonochemical synthesis characterization and biocompatibility studies of polymeric composites for biomedical applications

In this work the in situ synthesis of mixtures of Polymethylmethacrylate (PMMA), High Density Polyethylene (HDPE) and Polypropylene (PP) with biocompatible ceramics was carried out, using high frequency ultrasound as an energy source. Starting from calcium hydroxide and ammonium hydrogen phosphate, two different crystalline phases were obtained: hydroxyapatite (HA) and calcite (CaCO3). FTIR and XRD studies showed that for the materials prepared with HDPE, only CaCO3 was formed during the synthesis process. When Polypropylene used, mixtures of HA with CaCO3 were obtained, while for the materials synthesized with Polymethylmethacrylate, only pure HA was obtained. DSC analyses did not reveal any significant changes in the melting temperatures of HDPE and PP, nor in the glass transition temperature of PMMA with the incorporation of HA and CaCO3, in the polymeric matrices. TGA, showed that the decomposition temperatures of these materials increased with respect to those of the polymers alone, indicating a significant thermal stability. Biocompatibility tests with osteoblastic cells and Scanning Electron Microscopy (SEM) studies showed that the composites of PMMA with HA, PP with HA/CaCO3 and HDPE with CaCO3, are capable of promoting cell adhesion and proliferation mechanisms, revealing potential applications as biomaterials for bone replacement.

Development and 4D printing of magneto-responsive PMMA/TPU/Fe3O4 nanocomposites with superior shape memory and toughness properties

This paper introduces 4D printing of composites of polymethyl methacrylate (PMMA) and thermoplastic polyurethane (TPU) reinforced with Fe3O4 particles for the first time. PMMA/TPU blends with 70/30 wt% are selected as matrix with the best compatibility based on dynamic mechanical thermal analysis. Fe3O4 nanoparticles are added to the blends with 10 %, 15 % and 20 % weight ratios. Their addition enables remote actuation of the materials in a high frequency alternating magnetic field. Field emission scanning microscopic images confirms a full dispersion of nanoparticles inside the polymeric matrix. Nanocomposites with 20 wt% of Fe3O4 can perfectly recover the permanent shape within 1.5 min in the magnetic field. They also reveal perfect shape memory properties in the hot water. Moreover, all samples display a perfect shape fixity ratio. The addition of TPU significantly enhances the toughness and flexibility of the PMMA matrix. It is found that Fe3O4 nanoparticles further enhance the mechanical strength by 10 % to 15 %, although they reduce the strain at break from 17 % to 14 %. Finally, a gripper is 4D printed and its excellent performance in the magnetic field is demonstrated.

Effect of Hybrid Nanofillers on the Mechanical Characteristics of Polymethyl Methacrylate Denture Base Composite

The research study focused on enhancing the mechanical characteristics of polymethyl methacrylate (PMMA) denture bases. PMMA is commonly used in dentistry due to its easy fabrication, cost-effectiveness, and favourable physical properties. However, its limitations include low wear resistance, hardness, and mechanical strength, making it less suitable for long-term dental applications. To address these limitations, the study employed a combination of hybrid nano-fillers, specifically HNTs (halloysite nanotubes) and MWCNTs (multi-walled carbon nanotubes), at varying loading levels to improve the mechanical characteristics of the PMMA composite. These nano-fillers underwent treatment by using a coupling agent to enhance their compatibility with PMMA. Key findings of the research include that introducing HNTs/MWCNTs into the PMMA matrix led to a substantial increase in flexural strength, with a significant improvement of 109.1 MPa compared to unfilled PMMA. This indicates that the composite material became more resistant to bending or deformation. There was a substantial rise in flexural modulus values, suggesting improved stiffness in the nanocomposite compared to unfilled PMMA. In addition, the tensile strength of the PMMA composite increased by 64.4 MPa with the addition of the hybrid nano-fillers, indicating enhanced resistance to stretching or pulling forces. The study found that the improvement in flexural and tensile strength was dependent on the concentration of MWCNTs. Increasing the MWCNT concentration up to 0.75 wt.% led to improved mechanical properties, but further increases resulted in a reduction in PMMA properties. Although there was a modest improvement in Vickers hardness (approximately 18.93 kg/mm<sup>2</sup>), the addition of HNTs/MWCNTs as hybrid nano-fillers effectively enhanced the properties of the PMMA nanocomposite. The study concludes that incorporating hybrid nano-fillers into PMMA could contribute to the longevity and durability of dental composites, addressing some of the material's inherent limitations. The specific combination and concentration of nano-fillers played a crucial role in determining the mechanical properties of the resulting nanocomposite.

Experimental investigation on the tribo-mechanical behavior of PMMA reinforced by solid lubricant filler for dental implant applications

This study investigates the enhancement of mechanical and tribological behavior in polymethyl methacrylate (PMMA) composites reinforced with graphene oxide (GO) as a solid lubricant filler for advanced biomedical applications, particularly dental implants. PMMA/GO composites were prepared with varying weight percentages of GO (0, 0.2, 0.5, 0.7, and 1 wt. %) to assess their impact on material performance. A noteworthy improvement in both tensile strength and Young’s modulus was detected, reaching up to 141% and 10.6%, respectively, at optimized GO loadings of 1%. Microstructural analysis utilizing scanning electron microscopy for the worn surface revealed enhanced dispersion and interfacial adhesion between GO and the PMMA matrix, reinforcing mechanical coherence. Tribological properties also demonstrated enhancement, with PMMA composites containing 1 wt. % GO exhibiting optimal mechanical and tribological characteristics compared to lower weight fractions. Moreover, microscopic examination revealed a shift in the wear mechanism of the PMMA-GO composite, which was attributed to the lower friction coefficient obtained by GO integration.

Exploring the Tribological Behavior and Surface Characteristics of Polymethyl-Methacrylate/Hydroxyapatite (PMMA/HA) Composites: Investigating the Effect of Hydroxyapatite Weight Ratios on Wear Performance, Surface Roughness, and Hardness

This study conducts an analysis of the tribological characteristics of polymethyl-methacrylate (PMMA) composites reinforced with varying weight ratios of hydroxyapatite (HA) nanoparticles. It encompasses a systematic assessment of both hardness and surface roughness using the Shore-D hardness testing method and profilometer measurements, respectively. The results reveal a correlation between the HA nanoparticles weight ratio and hardness, indicating an increase in HA nanoparticles weight ratio corresponded to enhanced hardness. Moreover, higher HA nanoparticles weight ratios result in rougher surfaces, impacting composite performance. Specifically, the composite containing 5%-HA exhibited a Rq of 6 µm, which incrementally rose to 6.3 µm for the 10%-HA composite and significantly increased to 11.1 µm for the 15%-HA composite. Increasing HA weight ratios led to higher Rz values: 28 µm for 5%-HA, 35.1 µm for 10%-HA, and 72.5 µm for 15%-HA, indicating greater surface irregularities. The wear rates and friction coefficients are examined under applied forces ranging from 5 to 15 newtons across three distinct HA weight ratios (5%, 10%, and 15%). The results show a decreasing trend in wear rates with increasing weight ratios of HA, evidenced by weight loss rates of 0.0052 gr, 0.0011 gr, and 0.006 gr for samples S.1, S.2, and S.3, respectively, under a 15 N applied force. The friction coefficient analyses highlight complex dependencies on sliding distance, applied force, and HA weight ratio. Statistical tests, such as One-way analysis of variance (ANOVA) and effect size calculations, confirm significant applied force effects on friction coefficients, offering insights for optimizing PMMA/HA composite performance in biomedical applications.

Free-volume analysis of the structural and dielectric properties of PMMA/TeO2 composites via positron annihilation lifetime spectroscopy

PMMA (Poly methyl methacrylate) composites have promising potential for applications in optics and dielectric energy storage. To investigate the effects of TeO2 contents in PMMA in this respect, we studied their composites on light absorption in the UVvisible range, structural analysis via X-ray diffraction, dielectric characteristics, and free volume behavior. We added up to approximately 7 % of the weight concentration of the TeO2 micropowder to the PMMA matrix for effective dispersion because of the limitations of ultrasonic agitation. The XRD data demonstrate a widening of the peaks with a filler content of up to 4.8 % and agglomeration at 7 %, indicating TeO2 particle contact. An increase in absorbance was observed in the UVvisible spectrum of the PMMA/TeO2 composites with increasing TeO2 content up to 4.8 %. The dielectric constants exhibit a positive correlation with higher quantities of TeO2, and the polarization mechanism is interpreted by interface polarization and free volume. The free volume measured by positron annihilation lifetime spectroscopy (PALS) increases to 4.8 % but decreases to 7 %. The effect of the free volume within the matrix on the polarization distribution of TeO2 influenced the dielectric constant and the loss factor, which increased to 4.8 % and then decreased to 7 % due to agglomeration.

Enhanced PMMA Denture Bases Using Functionalized MWCNT Fused g-C3N4 Nanocomposites

This study presents the development and analysis of a new metal-free nanocomposite that incorporates functionalized multi-walled carbon nanotubes (f-MWCNTs) with graphitic carbon nitride (g-C3N4) for reinforcing polymethyl methacrylate (PMMA) denture bases. The f-MWCNTs were integrated with g-C3N4 nanoparticles, and their structural and morphological features were examined using various techniques, including X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), high-resolution transmission electron microscopy (HR-TEM), Fourier-transform infrared spectroscopy (FT-IR), and Raman spectroscopy. A mechanical blending process was employed to synthesize the nanocomposite by mixing 2 wt% of the f-MWCNT/g-C3N4 with PMMA polymer powder, followed by heat curing to form the composite material. Specimens for mechanical testing were crafted to measure flexural strength, impact resistance, compressive performance, and hardness. The findings revealed that the f-MWCNT/g-C3N4-reinforced PMMA composites outperformed standard PMMA in mechanical robustness. Surface examination of the tested samples through SEM showed distinctive dimpling and roughness, indicating a toughened fracture surface in comparison to pure PMMA and g-C3N4 samples. The study concludes that this innovative f-MWCNT/g-C3N4 composite is a promising reinforcement for PMMA denture bases, enhancing both their mechanical and physical attributes.Keywords: PMMA, functionalization, MWCNTs, Graphitic Carbide Nitride, Mechanical Properties and Denture Base

Thermal, Mechanical and Electrical Properties of Ag Nanoparticle–Polymethyl Methacrylate Composites Under Different Service Temperatures

Ag-nanoparticle-reinforced polymethyl methacrylate (AgNP/PMMA) composites are widely used in healthcare, electronics, construction, transportation and many other fields. As the service temperature fluctuates easily, it is necessary to study the temperature effect on the properties of AgNP/PMMA composites. In this work, a preparation method of mixing and hot-pressing was used to fabricate multifunctional AgNP/PMMA composites that are suitable for large-scale industrial production. AgNPs are found to disperse homogeneously in the PMMA matrix. The thermal conductivity of the composite with 15 vol% AgNPs is 116.19% higher than that of PMMA and decreases as the temperature rises. Flexural strength increases first and then decreases with the rising of AgNP content and service temperature, while the flexural modulus decreases gradually. The minimum electrical resistivity of the composite achieves 1.37 × 10−3 Ω·m, with a low percolation threshold of 5 vol%, an improvement of nine orders of magnitude over PMMA. The results demonstrate that the service temperature has a significant effect on the comprehensive properties of AgNP/PMMA composites.

Fabrication of Hair and Spider Silk Fiber-reinforced Polymethyl Methacrylate Composites and Evaluation of Their Mechanical Properties for Dental Applications

Fabrication of Hair and Spider Silk Fiber-reinforced Polymethyl Methacrylate Composites and Evaluation of Their Mechanical Properties for Dental Applications

Preparation of h‐BN/PMMA composites by in situ polymerization and research on their structure and properties

AbstractInorganic fillers like hexagonal boron nitride (h‐BN) have the potential to enhance the thermal conductivity of polymer mixtures. However, it has been restricted due to poor dispersion of particles in polymer matrices by melt mixing process. The addition of inorganic powders into sticky prepolymer is expected to alleviate the aggregation of powders. In this paper, h‐BN/polymethyl methacrylate (PMMA) composites were prepared by in situ polymerization of methyl methacrylate (MMA) with 5 and 20 μm of h‐BN particle as fillers respectively, for even distribution of fillers with in composites. The structures and properties of composites were characterized by FT‐IR, DSC, TGA, SEM, laser thermal conductivity meter and universal electronic tester. By SEM, it can be seen that a highly uniform dispersion of h‐BN in PMMA. When the mass fraction of h‐BN is 20 wt%, the thermal conductivity of the composites is increased by 107% for 5 μm h‐BN and 189% for 20 μm h‐BN, respectively. With the mass constituting of 5 wt% h‐BN, majority of mechanical characteristics of the composite, such as tensile strength, tensile modulus, along with impact strength, are enhanced, alongside a decrease in bending strength. This work would provide a filling strategy of h‐BN into the polymer matrices to achieve uniform dispersion, and enhance both the thermoconductivity and mechanical strength of thermoplastic composites.Highlights A technique for creating h‐BN/PMMA composites using in suit redox polymerization. Ehancing the thermal conductivity of these composites is achievable through the even distribution of h‐BN flakes within the PMMA matrix. It provides a reference for the design of future h‐BN/PMMA composites with favorable the thermal conductivity which achieves a good balance between performance and cost.

Mechanical properties and wear performance of denture base polymethyl methacrylate reinforced with nano Al2O3

Polymethyl methacrylate (PMMA) has been widely used as a material in dentistry. The deterioration of pure PMMA denture teeth is a significant issue that can alter the vertical dimensions of dentures. This study investigates the effect of aluminum oxide (Al2O3) nano-ceramic addition as reinforcements into the heat-cure acrylic resin denture teeth. The PMMA was reinforced with Al2O3 concentrations of 1, 3, 5, and 10 wt.%. The PMMA without ceramic addition is produced for comparison purposes. The color change, densification, microhardness, and compressive properties of the produced PMMA resin and its composites were investigated to detect the effect of Al2O3 nano ceramic addition on the physical and mechanical properties. Furthermore, the microstructure was also performed using scanning electron microscopy (SEM) analysis. A chewing simulator was utilized to conduct two-body wear testing, employing a human enamel antagonist. The wear behavior of the PMMA and their composites were assessed by measuring the weight loss after submitting them to 37,500 cycles. The SEM microstructure analysis revealed sound specimens of PMMA reinforced with 0, 1, 3, and 5 wt.% Al2O3 without any porosity and micro defects using the applied production procedures. In contrast, the aggregated sites and propagation of cracks were detected for the PMMA/10 wt.% Al2O3 specimen. The densification and hardness properties of the produced PMMA composites improved with increasing the Al2O3 additions. The microhardness of PMMA/10 wt.% Al2O3 improved by around 233% compared to the PMMA matrix. The higher compressive properties were detected for the PMMA/5 wt.% Al2O3 composite specimen with ultimate compressive strength (UCS) of 54.75 MPa and yield strength (YS) of 45.6 MPa and improved than the PMMA matrix by around 98 % and 117 %, respectively. In addition, incorporating Al2O3 nano-ceramic particles into a PMMA matrix revealed a significant improvement in the wear resistance of the produced composites compared to the PMMA matrix.

Fabrication, structural, and enhanced mechanical behavior of MgO substituted PMMA composites for dental applications

The most common denture material used for dentistry is poly-methyl-methacrylate (PMMA). Usually, the polymeric PMMA material has numerous biological, mechanical and cost-effective shortcomings. Hence, to resolve such types of drawbacks, attempts have been made to investigate fillers of the PMMA like alumina (Al2O3), silica (SiO2), zirconia (ZrO2) etc. For the enhancement of the PMMA properties a suitable additive is required for its orthopedic applications. Herein, the main motive of this study was to synthesize a magnesium oxide (MgO) reinforced polymer-based hybrid nano-composites by using heat cure method with superior optical, biological and mechanical characteristics. For the structural and vibrational studies of the composites, XRD and FT-IR were carried out. Herein, the percentage of crystallinity for all the fabricated composites were also calculated and found to be 14.79–30.31. Various physical and optical parameters such as density, band gap, Urbach energy, cutoff energy, cutoff wavelength, steepness parameter, electron–phonon interaction, refractive index, and optical dielectric constant were also studied and their values are found to be in the range of 1.21–1.394 g/cm3, 5.44–5.48 eV, 0.167–0.027 eV, 5.68 eV, 218 nm, 0.156–0.962, 4.273–0.693, 1.937–1.932, and 3.752–3.731 respectively. To evaluate the mechanical properties like compressive strength, flexural strength, and fracture toughness of the composites a Universal Testing Machine (UTM) was used and their values were 60.3 and 101 MPa, 78 and 40.3 MPa, 5.85 and 9.8 MPa-m1/2 respectively. Tribological tests of the composites were also carried out. In order to check the toxicity, MTT assay was also carried out for the PM0 and PM15 [(x)MgO + (100 − x) (C5O2H8)n] (x = 0 and 15) composites. This study provides a comprehensive insight into the structural, physical, optical, and biological features of the fabricated PMMA-MgO composites, highlighting the potential of the PM15 composite with its enhanced density, mechanical strength, and excellent biocompatibility for denture applications.

Effect of Nystatin Coated Copper Oxide (CuO) Particles on Mechanical, Thermal, and Antifungal Properties of Polymethyl Methacrylate (PMMA)–Based Denture Materials

Polymethyl methacrylate (PMMA) has garnered significant attention in the field of dentistry due to its wide applications. This paper proposes the incorporation of the nystatin coated copper oxide (CuO) particles having desirable conductivity and antifungal properties, as a filler in the PMMA denture to address their low thermal conductivity, low impact strength, low fatigue resistance, and microbial adhesion. The prepared nystatin coated CuO particles were characterized with several analytical techniques. The nystatin coated CuO particles were mixed in different ratios (0%, 1%, 2%, and 4%) in PMMA corresponding to groups C, E1, E2, and E3, respectively. The prepared samples of composite PMMA with nystatin coated CuO were evaluated to determine their transverse strength, impact strength, Vickers hardness (HV), and thermal conductivity. Furthermore, antifungal properties of CuO particles, nystatin coated CuO particles, and their acrylic composites were evaluated against Candida albicans. Scanning electron microscopy (SEM) analysis confirmed the particles’ spherical and irregular shapes. The particle sizes range from nano to micron level. Fourier‐transform infrared spectroscopy (FTIR) and energy dispersive X‐ray spectroscopy (EDX) analysis confirmed the coating of nystatin on CuO. X‐ray diffraction (XRD) analysis showed the diffraction patterns and planes of CuO monoclinic shape structure. The composite prepared to have higher values of HV (19.53 ± 0.65, 20.16 ± 0.37, and 21.11 ± 0.75, respectively) as compared to the control. The impact strength values were measured high at 14.12 ± 5.55 kJ/m2 for 2% containing nystatin coated CuO acrylic resins compared to control and other groups. The conductivity increased linearly with the addition of CuO particles. The addition of CuO particles causes a reduction in flexural strength as compared to the control group. As the concentration of nystatin coated CuO (1%, 2%, and 4%) in acrylic samples increased, the antifungal properties were improved. Thus, the incorporation of optimized concentrations of nystatin coated CuO particles in acrylic resin resulted in the improved mechanical, thermal, and antifungal properties.

Experimental study on flame spread over PMMA composites with addition of carbon nanotubes

Experiments on flame spread over cantilevered polymethyl methacrylate (PMMA) composites with addition carbon nanotubes (CNTs) were conducted and flame spread behaviors was analyzed. Results show that the two flame regions, surface flame and dripping flame, are distinguished because of the enhanced viscosity of the molten materials with the addition of CNTs. The combustion-supporting effect from the dripping flame promotes flame spread, the flame height and the flame spread rate are increased with CNTs. There is a power-law relationship between the whole flame height and the dripping flame height, H∝H20.682. The heat transfer analysis is also conducted based on the divisions of flame region. As the content of CNTs increases, the heat flux from surface flame is almost constant, but for dripping flame, it is twice as much as pure PMMA at 2.5% CNTs and the contribution in heat flux of dripping flame reaches 40%. The heat flux from dripping flame has important effects on sustaining flame spread and the increasing flame spread rate is mainly attributed to the enhancement of the heat feedback of dripping flame. These results are contrary to the effects of the flame retardancy by CNTs, which means the application of CNTs as flame retardants in polymers needs to consider the fire scenarios.

Tungsten-based polymer composite, a new lead-free material for efficient shielding of coupled neutron-gamma radiation fields: A FLUKA simulation study

Abstract Metal-based polymer composites, a new category of advanced materials, are advantageous for effective protection of radiation field. Recent report of fabrication of tungsten (W)-Poly methyl methacrylate (PMMA) composite microcellular foams with enhanced mechanical strength properties opens up the possibility of its use in radiation attenuation. Objective of this theoretical study is to assess the efficacy of W-based polymer composite, a new lead-free shielding material for attenuating coupled neutron-gamma radiations. Current paper utilizes open-source Monte Carlo code FLUKA to evaluate shielding efficiency of PMMA composites reinforced with varying concentration W particles. Study shows that, adding even 20 vol% of W particles can significantly improve radiation shielding ability of PMMA. Performance of analogous composition Pb-based polymer composite is also examined to demonstrate its inadequacy in radiation protection compared to W-based composite. Study reveals an interesting fact that for any shield dimension, total radiation dose follows an initial descending trend with increase in heavy metal (W/Pb) proportion up to certain optimum value where dose becomes minimum, beyond that dose increases. Optimum heavy metal concentrations are found to be 70 vol% and 30 vol% for W and Pb respectively, with minimum dose for Pb shield being two orders of higher magnitude. Study is further extended to investigate shielding efficiency of conventional double-layer laminates employing W and PMMA in both high-Z/low-Z and low-Z/high-Z configurations as well as optimum concentration of W-PMMA composite and PMMA. It is shown that among all the potential designs, newly introduced composite-based double-layer shield performs best in terms of volumetric dose while single-layer optimized composite shield offers least specific dose.

Preparation of bio-based heat storage microcapsules of cellulose acetate butyrate/ polymethylmethacrylate composite by micro-suspension polymerization

ABSTRACT Because of environmental concerns, the utilization of bio-based, renewable resource materials has attracted great attention for a wide range of applications. In this research, green cellulose-based microcapsules containing capric acid (CA) as a bio-heat storage material were prepared. Cellulose acetate butyrate (CAB)/methacrylate polymer composite particles were produced by microsuspension iodine transfer polymerization to encapsulate CA. The influences of methacrylate polymer type and amount on microcapsule morphology, encapsulation efficiency (EE) and thermal properties were investigated. Using methyl methacrylate (MMA) monomer, the colloidal stable spherical microcapsules with smooth surfaces and core-shell morphology were obtained. Although high percentages of EE, ≥70%, were obtained at all CAB:MMA weight ratios, the latent heats of the encapsulated CA were lower than those of the original ones which may be due to the incomplete phase separation of the CAB/PMMA shell and CA core. The increase of CA content up to 60% provided stable spherical microcapsules with a maximum loading of 59% and 97% EE. After thermal cycling for 100 cycles, stable microcapsules still remained with stable thermal properties. The obtained bio-based microcapsules would be well applied for heat storage and temperature control applications.

Understanding significantly reinforced polymethyl methacrylate composites induced by two‐dimensional Tin+1Cn from an atomistic perspective

AbstractMXenes, which have good reinforcing and toughening effects, can serve as excellent polymer additives. However, the mechanism whereby MXenes act has not been revealed. In this study, to understand the reinforcement effect of Tin+1Cn on polymethyl methacrylate (PMMA) from an atomistic perspective, we used molecular dynamics to conduct unidirectional tensile simulations of PMMA composites reinforced with monolayer Ti2C and Ti3C2 sheets. The results showed that Ti3C2 can more significantly improve the mechanical properties of the PMMA polymer than Ti2C, and the yield stress and Young's modulus of the Ti3C2/PMMA complexes were respectively 54.39% and 73.46% higher than the Ti2C/PMMA complexes. To further reveal the interaction mechanism between Tin+1Cn and PMMA, different separation speeds were used to simulate the pull‐out of Tin+1Cn from the PMMA matrix. The results showed that, in addition to the enhancement of interfacial strength by non‐bonding van der Waals forces, there were TiO and CTi bonds between Tin+1Cn and PMMA, which further increased the interfacial strength. Ti3C2 formed a denser interfacial region with PMMA, it could more effectively resist the formation and expansion of cracks. These findings may provide an important theoretical basis to design new type of MXene/polymer composites with excellent mechanical properties.Highlights MXene greatly improved the mechanical properties of the PMMA matrix. Formation of chemical bonds improved connection between the MXene and PMMA. The addition of MXene slows down the rate of crack propagation in PMMA.

Surface, mechanical and chemical properties of modified denture resin using natural biopolymer.

This laboratory study determined the surface, mechanical and chemical properties of polymethyl methacrylate (PMMA) denture resin reinforced with micron-sized Gum Arabic (GA) powder in different weight ratios. This laboratory study was conducted at the Dental Health Department of the College of Applied Medical Sciences, King Saud University, Riyadh, Saudi Arabia from November 2022 to February 2023. Three experimental denture resins were prepared by incorporating GA powder in heat-polymerized PMMA powder using different wt.% (5, 10, and 20 wt.%). While pristine PMMA served as the control group. A total of ten bar-shaped specimens with dimensions of 65 mm × 10 mm × 3.5 mm were prepared for each study group. The surface properties (micro CT and SEM evaluation), mechanical properties (Nanohardness, elastic modulus and flexural strength) and chemical properties (FTIR) were conducted. The data were statistically analyzed using the one-way analysis of variance and Tukey's post hoc tests (p<0.05). The surface and bulk properties of experimental GA-reinforced PMMA resin materials deteriorated while the mechanical properties were also negatively altered using GA-based PMMA denture resin. A linear correlation was observed between weak mechanical properties and increasing wt.% of GA in denture resin. The incorporation of GA powder in denture resin might not be a viable option. The surface and mechanical properties of experimental PMMA composites were adversely affected compared to the control group.

Enhancing Polymethyl Methacrylate Prostheses for Cranioplasty with Ti mesh Inlays.

Biocompatible polymers such as polymethyl methacrylate (PMMA), despite fulfilling biomedical aspects, lack the mechanical strength needed for hard-tissue implant applications. This gap can be closed by using composites with metallic reinforcements, as their adaptable mechanical properties can overcome this problem. Keeping this in mind, novel Ti-mesh-reinforced PMMA composites were developed. The influence of the orientation and volume fraction of the mesh on the mechanical properties of the composites was investigated. The composites were prepared by adding Ti meshes between PMMA layers, cured by hot-pressing above the glass transition temperature of PMMA, where the interdiffusion of PMMA through the spaces in the Ti mesh provided sufficient mechanical clamping and adhesion between the layers. The increase in the volume fraction of Ti led to a tremendous improvement in the mechanical properties of the composites. A significant anisotropic behaviour was analysed depending on the direction of the mesh. Furthermore, the shaping possibilities of these composites were investigated via four-point bending tests. High shaping possibility was found for these composites when they were shaped at elevated temperature. These promising results show the potential of these materials to be used for patient-specific implant applications.