Structure and Mechanical Behavior of Isotactic Polypropylene Composites Filled with Silver Nanoparticles

Abstract

Isotactic polypropylene (PP) nanocomposites containing 0.1, 0.3, 0.5 and 1.0 wt % silver (Ag) nanoparticles were prepared via melt compounding in a twin-screw extruder followed by injection molding The effects of the Ag nanoparticle additions on the structure and mechanical behavior of PP were studied using DSC, WXRD, optical microscopy, tensile and Izod impact techniques. DSC and WXRD measurements showed that the addition of only 0.1 wt% Ag nanoparticles promote the formation of β-form PP. Further increasing Ag content would not lead to additional increase of the β-PP phase content. The induced β-form PP phase is beneficial to enhance the impact strength and tensile ductility of the PP/Ag nanocomposites.

Morphology and properties of highly filled iPP/TiO2 nanocomposites

“…However, the b-form crystal of iPP is a metastable phase which is occasionally observed as a minor crystal phase in iPP that tends to transform to a-form under mechanical to thermal stimulates [21,22,[24][25][26][27]. Although presence of the b-phase leads to lower modulus and yield strength in iPP, its excellent effects on enhancement of toughness, impact strength, and heat distortion temperature of iPP has attracted much attention from research and industrial applications [21][22][23][28][29][30].…”

“…Isothermal crystallization, quenching, large temperature gradient, shear-induced crystallization, and addition of extrinsic b-nucleating agents, other polymers or inorganic fillers may cause to formation of b-phase crystals in iPP [22,23,27,[29][30][31][32][33]. Addition of selective b-nucleating agents, which are generally crystallizable organic compounds with low molecular weight (e.g., quinacridone dye, triphenodithiazine, and pimelic acid), is the common method to obtain high b-phase content in iPP [20,22,23,26,27,30].…”

“…Addition of selective b-nucleating agents, which are generally crystallizable organic compounds with low molecular weight (e.g., quinacridone dye, triphenodithiazine, and pimelic acid), is the common method to obtain high b-phase content in iPP [20,22,23,26,27,30].…”

Nucleation of isotactic polypropylene crystallization by gold nanoparticles

“…In the recent years, the nucleation of iPP crystallization by different nanoparticles was studied 3–9. It was found that exfoliated organo‐modified monmorillonite (o‐MMT) weakly nucleated the iPP crystallization 3, 4.…”

“…A stronger effect was described by Jain et al8 In iPP with 0.5–1 wt % of SiO 2 particles having sizes in the range of 30–80 nm, an increase of the iPP crystallization temperature by 7 °C was evidenced. A total of 0.1–1 wt % of silver nanoparticles dispersed in iPP caused elevation of the crystallization temperature by 4 °C 9. One notes that addition of 0.2–0.5 wt % of an efficient nucleating agent, sorbitol derivative, increases the iPP crystallization temperature much stronger, by ∼ 18 °C during cooling at 10 °C/min 10.…”