Surface‐modified silica nanoparticle–reinforced poly(ethylene 2,6‐naphthalate)

Abstract

ABSTRACT:The effect of stearic acid modification on the dispersity of silica nanoparticles and the adhesion between the filler and polymer matrix with stearic acid concentration were investigated. The wettability of silica nanoparticles was improved by the addition of stearic acid. The presence of adsorbed stearic acid on the surface of the silica nanoparticles reduced the interaction between silica nanoparticles, and reduced the size of agglomerates with increasing concentration. Silica nanoparticle-reinforced poly(ethylene 2,6-naphthalate) (PEN) composites were melt-blended to investigate their mechanical properties and the processability of the composites. The torque and total torque values of the composites decreased with increasing silica nanoparticle content. The tensile moduli of the composites reinforced with unmodified silica nanoparticles increased with increasing silica content, whereas the tensile strength and elongation decreased. However, the stearic acid-modified silica nanoparticle-reinforced PEN composites exhibited increased elongation and decreased tensile moduli with increasing content because stearic acid, which adsorbs onto the surface of the silica nanoparticles in layers thicker than a monolayer, acts as a plasticizer during the melt-compounding stage.

Comparative study of dielectric and mechanical properties of HDPE-MWCNT-SiO 2 nanocomposites

“…(2) for a very low value of K, thereby, indicating the existence of enhanced interfacial interactions. Similar observation has been made for a low K value of silica nanoparticles reinforced poly (ethylene 2,6 napthalate) by Ahn et al [27].…”

Physical properties and crystallization behavior of poly(lactide)/poly(methyl methacrylate)/silica composites

“…The as‐received nanosilica particles were subjected to surface modification by using stearic acid to impart the hydrophobic characteristic onto the surface of the silica particles. The stearic acid ( M w = 284.48 g/mol, mp = 68–71°C, bp = 361°C) was first added to isopropyl alcohol, and the mixture was stirred for ∼1 h at room temperature. Then, the silica nanoparticles were added to the mixture so that the carboxylic group of stearic acid was expected to physically attract with the silica particles to impart a hydrophobic characteristic on the surface of the silica particles .…”

Improvements in the oxygen barrier property of polypropylene nanocomposites

“…Montmorillonite (MMT) is a filler material that consists of an aluminum silicate clay. It has a high surface area of 800 gsm (grams/square meter) and a high aspect ratio, and it is widely used in studies of polymer‐layered silicate nanocomposite systems . Because of its abundance in nature, it also has advantages in cost, and has been widely used in many applications.…”

“…There are many polar groups on the surface of the layered silicate together with the presence of cations, and the hydrophilicity is so great that water molecules are always present between the layers. When each layer is stacked, a constant Van der Waals space called an interlamellar gallery is formed …”

“…The purpose of preparing polymer composites is to disperse the filler as uniformly as possible to increase not only the gas barrier property but also the mechanical and thermal properties . However, the compatibility and dispersibility between PP and nanoclay present a problem because of the polarity and hydrophobic/hydrophilicity.…”