Characterization and properties of activated nanosilica/polypropylene composites with coupling agents

Abstract

In this work, nanosilica/polypropylene composites containing 1 wt% of silica nanoparticles were prepared by melt mixing in a Thermo Haake internal mixer. Prior compounding, nanosilica was subjected to surface activation using sodium hydroxide (NaOH) solution. The effectiveness of the activation process was evaluated by measuring the amount of hydroxyl groups (À ÀOH) on the surface of nanosilica via titration method and supported by FTIR analysis. Two coupling agents namely 3-aminopropyl triethoxysilane (APTES) and neopentyl (diallyl)oxy,tri(dioctyl) phosphate titanate (Lica 12) were used for surface treatment after activation process. The mechanical properties of polypropylene matrix reinforced with silica nanoparticles were determined by tensile and impact test. Hydroxyl groups on the nanosilica surface played an important role in enhancing the treatment with silane coupling agents. To increase the amount of hydroxyl groups on the nanosilica surface, the optimum concentration of NaOH is 1 mol%. Tensile strength, tensile modulus, and impact strength of nanosilica/PP composites improved with activation process. As the coupling agent is concerned, APTES coupling agent is more pronounced in enhancing the mechanical properties of the composites when compared with Lica 12 coupling agent.FIG. 6. Tensile properties of nanosilica filled polypropylene as a function of coupling agents at 1 wt% filler content: (a) tensile strength, (b) Young's modulus, (c) elongation at break, and (d) un-notched Izod impact strength.

Characterization polyethylene terephthalate nanocomposites mixing with nano-silica and titanium oxide

“…Other authors have confirmed this phenomenon in cases where nano-silica and TiO2 was incorporated into multilayer organic coatings [15][16][17][18][19][20][21][22].…”

Superhydrophobic coatings fabricated with polytetrafluoroethylene and SiO2 nanoparticles by spraying process on carbon steel surfaces

“…The band at around 1630 cm −1 is the OH bending vibration of the adsorbed H 2 O [29]. The peaks at ∼1100, ∼800, and ∼470 cm −1 are the stretching vibration of Si OH, the asymmetric stretching vibration of Si O Si, and the symmetric stretching and bending vibrations of Si O Si, respectively [26,27,29,38]. The band at around 950 cm −1 is the out-of-plane bending vibration of OH [28].…”

“…The broad absorption peak at ∼3440 cm −1 corresponds to Si OH and the adsorbed H 2 O [28]. The band at around 1630 cm −1 is the OH bending vibration of the adsorbed H 2 O [29]. The peaks at ∼1100, ∼800, and ∼470 cm −1 are the stretching vibration of Si OH, the asymmetric stretching vibration of Si O Si, and the symmetric stretching and bending vibrations of Si O Si, respectively [26,27,29,38].…”

“…6 g raw SiO 2 was slowly added into the mixture. After 30 min, the white precipitates were filtered through suction, washed three times with DI water, and dried overnight at 130 • C. The possible mechanism for H-SiO 2 formation was elaborated in Scheme 1 [24,[27][28][29], where R is the organic group in KH-570. R-SiO 2 and H-SiO 2 were softly grinded before passing through a 150-mesh stainless steel sieve to remove bulk powders and impurities.…”

Nanomaterials for Construction Engineering-A Review

“…NANOSILICA Besides having a low cost (each gram of nanosilica costs 60 paise) budget, high compressive strength (3801 psi), tensile strength (117.7 MPa), high surface area (750 m 2 /gm), ability to prevent silicosis, reducing percentage of CO 2 , nanosilica (particle size = 4-100 nm, colloidal solid percentage = 30%) also helps in checking solid waste pollution when mixed with recycled concrete aggregates [40]- [43]. Stress-strain behavior of nanosilica is presented in Fig.…”