Effect of preparation method on the properties of poly(methyl methacrylate)/mesoporous silica composites

Abstract

The preparation method of a polymer composite and the filler loading are amongst the factors that influence the properties of the final composites. This article studies the effect of these factors on the thermal stability and thermal degradation kinetics of poly(methyl methacrylate) (PMMA)/mesoporous silica (MCM-41) composites filled with small amounts of MCM-41. The PMMA/MCM-41 composites were prepared through in situ polymerisation and melt mixing methods, with MCM-41 loadings of 0.1, 0.3, and 0.5 wt.%. The presence of MCM-41 increased the thermal stability of PMMA/MCM-41 composites prepared by melt mixing, but in the case of the in situ polymerised samples, the MCM-41 accelerated the degradation of the polymer. As a result, the activation energy was low and less energy was required to initiate and propagate the degradation process of these composites. The small-angle X-ray scattering (SAXS) measurements showed that the preparation method of the composites had no influence on the pore size of MCM-41, but the PMMAs used in the two methods both had shorter chains than the MCM-41 pore size. This allowed the polymer chains to be trapped inside the pores of the filler and be immobilised, as was observed from nuclear magnetic resonance (NMR) spectroscopy. The immobilisation of the polymer chains was more significant in the in situ polymerised samples.

Piezoelectric properties of zinc oxide/iron oxide filled polyvinylidene fluoride nanocomposite fibers

“…These electroactive phases subsequently improve with dipole alignment processes like corona poling and with the addition of nanomaterials [16]. Electrospinning is identified as a good manufacturing technique, which causes the dipole alignment as an alternative to additional poling processes [17]. Moreover, soft and flexible fibers satisfy the lightweight and convenient designs useful for industrial applications.…”

“…Moreover, soft and flexible fibers satisfy the lightweight and convenient designs useful for industrial applications. Various nucleating nanofillers added to polymeric medium also improve the thermal, electrical, and mechanical properties, in addition to the piezoelectricity [17,18].…”

Tuning Topology and Scaffolding Units in Nanoporous Polymeric Materials for Efficient Iodine Adsorption and Detection

“…The past few decades have witnessed an explosion of the emerging nanoporous materials due to the rapid development of advanced synthesis technologies and their wide application potentials. Various nanoporous materials have been designed, synthesized, and studied, including their special permeability, adsorption, mechanical properties, propagation properties, etc. − In the field of adsorption and separation, porosity (i.e., surface area, pore volume, and pore size) has proved to be one of the key parameters determining the separation/adsorption performances. There are many approaches to construct porous materials, such as the template method, freeze-drying, and the introduction of thermoresponsive polymers that collapse to form pores when heated. − On the other hand, using different structural elements or functional monomers to construct nanoporous materials, introducing new properties, realizing the performance integration of nanoporous materials, stimulating synergies, improving performance, and broadening the application range are also one of the current development trends of functional porous materials.…”

Piezoelectric Properties of Zinc Oxide/Iron Oxide filled Polyvinylidene fluoride Nanocomposite Fibers

“…Electrospinning is identi ed as a good manufacturing technique, which causes the dipole alignment as an alternative to additional poling processes [17]. Moreover, soft and exible bers satisfy the lightweight and convenient designs useful for industrial applications.…”

“…Moreover, soft and exible bers satisfy the lightweight and convenient designs useful for industrial applications. Various nucleating nano llers added to polymeric medium also improve the thermal, electrical, and mechanical properties, in addition to the piezoelectricity [17,18].…”