Dispersion control of raw and modified silica particles in PMMA. Impact on mechanical properties, from experiments to modelling

Abstract

Structure and properties of PMMA/silica composites were characterized by various methods including SEM, TGA, rheology, microscopic level evaluation of nanoreinforcement effect on properties. Static modulus and yield strength of PMMA are enhanced with silica incorporation regardless of their dispersion or functionalization. However, composites ultimate properties are strongly affected by fillers characteristics. As expected, better performances are associated to well-dispersed and functionalized silica. A finite element modelling with interface debonding through cohesive model and interfacial area is introduced to reproduce the sensibility of tensile test response to fillers surface functionalization. Experimental results confirmed this modelling: at constant low weight rate, ultimate composites properties are mostly affected by any microstructural changes. An analysis of local stress confirms the premature breakage of composite with pristine silica. Finally, by considering the expected properties, functionalization of silica is not always a necessity. Instead of particle functionalization, a dispersion protocol could be advantageously used to reach interesting composite properties.

Hygrothermal aging effect on the properties of PMMA nanocomposites reinforced by ceramic nanoparticles

“…Homogeneity is a critical challenge among the various preparation methods of particle-reinforced nanocomposites since the interaction between nano-filler and matrix is the most urgent factor in controlling the properties of nanocomposites. 30,31 The microstructure of produced nanocomposites is illustrated in Figures 2(a)–(d). The evaluation of the SEM images in different magnifications indicated that there is no crucial agglomeration region, and nanoparticles have been distributed appropriately in the polymeric matrix.

Figure 2.SEM micrographs of fractured surfaces for a) pure PMMA and PMMA nanocomposites containing b) 2 wt% TiO 2 , c) 2 wt% SiO 2 , and d) 1 wt% Al 2 O 3 .

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Synthesis, Characterization and Application of Biobased Unsaturated Polyester Resin Reinforced with Unmodified/Modified Biosilica Nanoparticles

“…Various types of silanes are proven to be very efficient for reducing the surface hydroxyl group content in silica particles [ 27 ]. Siot et al investigated the influence of unmodified and poly(methyl methacrylate) (PMMA)-modified silica on mechanical properties [ 28 ]. They showed that particle dispersion processes and modifications with PMMA have a great influence on yield stress and Young’s modulus.…”

Inorganically modified particles FeAl-LDH@SiO 2 as reinforcement in poly (methyl) methacrylate matrix composite

“…The use of these composites is becoming increasingly popular in the restoration of teeth, where they replace metal dental amalgams, and the reason for that is they are more aesthetically pleasing, have better mechanical properties and are easy to make [16][17][18][19][20]. Silica is the most common reinforcement in dental composite materials [21][22][23]. Composites containing silica have good compatibility with the tissue, they open a great possibility to be shaped in a defined form and their colour can be adjusted to fit many aesthetic demands.…”