Enhancement of thermal and mechanical properties of poly(MMA-co-BA)/Cloisite 30B nanocomposites by ultrasound-assisted in-situ emulsion polymerization

Abstract

This study reports synthesis and characterization of poly(MMA-co-BA)/Cloisite 30B (organo-modified montmorillonite clay) nanocomposites by ultrasound-assisted in-situ emulsion polymerization. Copolymers have been synthesized with MMA:BA monomer ratio of 4:1, and varying clay loading (1-5wt% monomer). The poly(MMA-co-BA)/Cloisite 30B nanocomposites have been characterized for their thermal and mechanical properties. Ultrasonically synthesized nanocomposites have been revealed to possess higher thermal degradation resistance and mechanical strength than the nanocomposites synthesized using conventional techniques. These properties, however, show an optimum (or maxima) with clay loading. The maximum values of thermal and mechanical properties of the nanocomposites with optimum clay loading are as follows. Thermal degradation temperatures: T=320°C (4wt%), T=373°C (4wt%), maximum degradation temperature=384°C (4wt%); glass transition temperature=64.8°C (4wt%); tensile strength=20MPa (2wt%), Young's modulus=1.31GPa (2wt%), Percentage elongation=17.5% (1wt%). Enhanced properties of poly(MMA-co-BA)/Cloisite 30B nanocomposites are attributed to effective exfoliation and dispersion of clay nanoparticles in copolymer matrix due to intense micro-convection induced by ultrasound and cavitation. Clay platelets help in effective heat absorption with maximum surface interaction/adhesion that results in increased thermal resistivity of nanocomposites. Hindered motion of the copolymer chains due to clay platelets results in enhancement of tensile strength and Young's modulus of nanocomposite. Rheological (liquid) study of the nanocomposites reveals that nanocomposites have higher yield stress and infinite shear viscosity than neat copolymer. Nonetheless, nanocomposites still display shear thinning behavior - which is typical of the neat copolymer.

A Review of the Synthesis and Applications of Polymer–Nanoclay Composites

“…The prepared composites exhibited mixed and intercalated morphologies, which contributed to promising properties for optical electronic devices. Sharma et al [108] enhanced the thermal and mechanical properties of poly(MMA-co-BA)/Cloisite ® 30B (BYK Additives & Instrument, Wesel, Germany) composites by using an ultrasound-assisted in-situ emulsion polymerization method. This innovative method provided higher thermal degradation resistance and mechanical strength than the composites synthesized using conventional techniques.…”

Preparation and characterization of polymer‐Ti3C2Tx (MXene) composite nanofibers produced via electrospinning

“…[26][27][28] For example, poly(methyl methacrylate (PMMA)copolymer-butyl acrylate (BA))/Cloisite 30B (organo-modified montmorillonite (MMT) clay) nanocomposites with varying clay loading between 1-5 wt%, experienced a marked increase in thermal degradation temperature and glass transition temperature over those of the base Accepted Article polymer. 29 These properties were attributed to the maximized surface interaction/adhesion of the clay platelets resulting from the uniform dispersion of individual clay nanoparticles in the polymer matrix. 29 Exfoliated polystyrene nanocomposites using functionalized montmorillonite were found to have a higher dynamic modulus with increased clay loading.…”

“…29 These properties were attributed to the maximized surface interaction/adhesion of the clay platelets resulting from the uniform dispersion of individual clay nanoparticles in the polymer matrix. 29 Exfoliated polystyrene nanocomposites using functionalized montmorillonite were found to have a higher dynamic modulus with increased clay loading. 30 More impressively, nylon-6 with 4.1 wt% of montmorillonite loading showed a 103% increase in Young's modulus, 49% increase in tensile strength, and a 146% increase in heat distortion temperature.…”

Electrical and mechanical properties of partially bio‐based PP/PBS blends nanocomposites elaborated by twin‐screw extrusion

“…Organically modified montmorillonite (OMMT) based nanocomposites materials raised considerable attention in academic and industrial sectors owing to the improvement of their barrier, thermal, electrical, and mechanical properties when a very small amount (0.5-5 wt%) is added to the polymeric matrix. [1][2][3][4][5][6][7][8] The mechanical [9][10][11][12][13] and electrical [14][15][16][17][18][19][20] improvements are related to the beneficial interaction between the OMMT and the polymer molecules. Indeed, polymer nanocomposites obtained, possess many interesting features such as more discharge endurance, better thermal and mechanical properties, lower quantity of accumulated space charges, longer lifetime.…”