Sonochemical Synthesis of PMMA/Cloisite 30B Nanocomposites: A Mechanistic Investigation

Abstract

Summary: This study attempts to gain mechanistic insight into the influence of ultrasound and cavitation in synthesis of polymethyl methacrylate (PMMA) and its nanocomposite using the organo-modified Cloisite 30B clay. A statistical design of experiments (Central Composite Design with Response Surface Methodology) has been used to find optimum values of quantities of monomer (15 g), initiator (0.75 g) and surfactant (0.87 g) in the synthesis of neat PMMA in 60 mL of total reaction volume. Using these optimized values, the nanocomposites have been synthesized using varying concentrations of clay. Characterization of the nanocomposites was done with standard techniques of XRD, FTIR, DSC, TGA, particle size analysis, zeta potential, SEM and TEM. The nanocomposites have been revealed to have better thermal properties (maximum degradation temperature of 277 C at T 5% and glass transition temperature of 120 C at 2% clay loading) as compared to neat PMMA. The results have been explained on the basis of basic physical and chemical principles of ultrasound and cavitation. The physical effect of ultrasound and cavitation of generation of intense microturbulence in the system has been revealed to play major role in the process rather than the chemical effect of generation of radicals.

Ultrasound–assisted synthesis and characterization of polymethyl methacrylate/reduced graphene oxide nanocomposites

“…These effects lead to higher encapsulation and better dispersion of nanofiller in the polymer matrix as compared to conventional methods employing mechanical agitation. Nanocomposites synthesized with sonication have better physical properties than those synthesized with conventional techniques, as demonstrated in our previous studies …”

Cloisite Microrobots as Self-Propelling Cleaners for Fast and Efficient Removal of Improvised Organophosphate Nerve Agents

“…As such, Cloisite 15A was found to have a positive ζ potential (42.4 mV) while Cloisite 20A had a negative ζ-potential value (−10.9 mV). It is noted that the ζ-potential measured increased as the modifier concentration increases . Cloisite 93A was found to possess the most negative ζ potential value (−45.6 mV) while Cloisite 10A had the most positive value (42.4 mV).…”

Sonochemical Synthesis of Polymer Nanocomposites

“…3A [34]. The nanocomposites of PMMA-Cloisite-30B for all loadings (1-5 wt.%) showed no peak, while the pristine clay exhibits a peak at 2θ = 4.85 o corresponds to d (001).…”

“…The nanocomposite synthesis of PMMA-Cloisite-30B has been accomplished using the optimum condition (viz. 15 g MMA, 0.75 g KPS and 0.87 g SDS) obtained from statistical design of experiments [34]. Further, nanocomposites of PMMA/Cloisite-30B with different clay loading (viz.…”

“…Figure 3: XRD diffractogram of (A) pristine Cloisite 30B clay and different loadings of PMMA/Cloisite 30B nanocomposites [34] (B) Pristine clay and clay after sonication [35].…”