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Abstract Polymer‐clay nanocomposites (PCNs) are commonly applied as multi‐functional structural materials with exceptional thermomechanical properties, while maintaining the characteristics of lightweight and optical clarity. In this study, building upon previously developed coarse‐grained (CG) models for nanoclay and poly (methyl methacrylate) (PMMA), we employ molecular dynamics (MD) simulations to systematically investigate the thermomechanical properties of PCNs when arranged in stacked configurations. Incorporating stacked clay nanofillers into a polymer matrix, we systematically conduct shear and tensile simulations to investigate the influences of variations in weight percentage, system temperature, and nanoclay size on the thermomechanical properties of PCNs at a fundamental level. The weight percentage of nanoclay in nanocomposites proves to have a significant influence on both the shear and Young's modulus (e.g., the addition of 10 Wt% nanoclay leads to an increase of 32.6% in the Young's modulus), with each exhibiting greater mechanical strength in the in‐plane direction compared to the out‐of‐plane direction, and the disparity between these two directions further widens with an increase in the weight percentage of nanoclay. Furthermore, the increase in the size of nanoclay contributes to an overall modulus enhancement in the composite while the growth reaches a saturation point after a certain threshold of about 10 nm. Our simulation results indicate that the overall dynamics of PMMA are suppressed due to the strong interactions between nanoclay and PMMA, where the confinement effect on local segmental dynamics of PMMA decays from the nanoclay‐polymer interface to the polymer matrix. Our findings provide valuable molecular‐level insights into microstructural and dynamical features of PCNs under deformation, emphasizing the pivotal role of clay‐polymer interface in influencing the thermomechanical properties of the composite materials. HighlightsCG modeling is performed to explore the thermomechanical behavior of PCN.Effects of nanoclay weight percentage and size on modulus are studied.Interface leads to nanoconfinement effect onTgand molecular stiffness.Correlations between molecular stiffness and modulus are identified.Simulations show spatial variation of dynamical heterogeneity.
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Denture base poly(methyl methacrylate) reinforced with SrTiO3 / Y2O3 : Structural, morphological and mechanical analysis
Abstract This study presented the use of SrTiO3/Y2O3nanoparticles for the reinforcement of dental poly(methyl methacrylate) (PMMA) to enhance its mechanical properties important for everyday use of denture base materials. The average crystallite size of prepared nanoparticles was 19.9 nm. The influence of 0.5, 1.0, and 1.5 wt% SrTiO3/Y2O3loading on absorbed impact energy, microhardness and tensile properties was investigated. Scanning electron microscopy of the composite fracture surface revealed multiple toughening mechanisms, with agglomerates directly included in the crack pinning, indicating improvement in mechanical performance. Dynamic mechanical analysis proved that agglomerates improved the elastic behavior of PMMA and confirmed the absence of a residual monomer. After the incorporation of SrTiO3/Y2O3, the mechanical properties of composites showed a high increase compared to neat PMMA. The optimal concentration of nanoparticles was 1 wt%, for which the microhardness, modulus of elasticity, and absorbed impact energy were higher by 218.4%, 65.8% and 135.6%, respectively. With such a high increase, this research showed that SrTiO3/Y2O3represents an efficient filler which use does not have to be limited to dental materials. HighlightsSrTiO3/Y2O3hybrid nanoparticles were prepared.PMMA‐SrTiO3/Y2O3composite showed increase in impact resistance up to 135.4%.Elastic behavior of PMMA was improved.With 1 wt% of SrTiO3/Y2O3, microhardness increased by 218.4%.
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- PAR ID:
- 10566127
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Polymer Composites
- Volume:
- 46
- Issue:
- 10
- ISSN:
- 0272-8397
- Format(s):
- Medium: X Size: p. 8831-8840
- Size(s):
- p. 8831-8840
- Sponsoring Org:
- National Science Foundation
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