Study on the synthesis and properties of polyacrylamide/Na-montmorillonite nanocomposites

Abstract

A series polyacrylamide/Na-montmorillonite nanocomposites was prepared by in situ free radical polymerization in aqueous medium using benzoyl peroxide (Bz2O2) as a radical initiator. To characterize the resultant nanocomposites, Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and thermogravimetric analysis techniques were used. The moisture retain, water uptake, antibacterial properties, BET specific surface area and specific nanopore volume of nanocomposites were determined. The X-ray diffraction pattern showed that the polyacrylamide was intercalated up to 60.0 mass% acrylamide concentration, and then montmorillonite layers exfoliated into the polyacrylamide matrix. The interlayer spacing ( d001) of the montmorillonite increased from 1.19 to 1.90 nm by intercalation. Transmission electron microscopy views showed that the Na-montmorillonite partially exfoliated in polyacrylamide. The nanocomposites exhibited better thermal stability than the pure polyacrylamide.

Preparation, characterization, and properties of polystyrene/Na-montmorillonite composites

“…In situ polymerization of PS/unmodified Na-MMT composites was carried out with different amounts of styrene monomer in aqueous medium. 3,15,16 The nomenclature of composite samples and polymerization conditions is summarized in Table 1. In this synthesis procedure, 1 g of Na-MMT was dispersed in 24 mL of distilled water in a 100-mL Pyrex glass tube and the obtained dispersion was stirred at a rate of 100 r min −1 in overnight at the room temperature for each polymerization.…”

Preparation and characterization of polymethacrylamide/halloysite composites

“…Halloysite taken from Balıkesir/Turkey deposit was used as a clay mineral after purification. Chemical composition of the halloysite is as mass percent: 44.840 SiO 2 , 34.610 Al 2 O 3 , 0.414 Fe 2 O 3 , 0.104 TiO 2 , 0.124 CaO, 0.001 MgO, 0.005 Na 2 O, 0.309 K 2 O, and 18.600 loss on ignition (LOI), which were determined by atomic absorption spectroscopy explained in the literature …”

“…Polymer/clay composites have been studied extensively in recent years. These polymer composites show significant improvements in low clay loadings, especially in mechanical and reduced flammability . Clay minerals are layered or fibrous natural compounds of relatively low cost, abundant, and environmentally friendly, and exhibit excellent chemical as well as thermal stability for synthesis of polymer/clay composites.…”

“…Over the past two decades, a considerable number of studies on polymer/clay composites were available in the literature. In our earlier works, the thermal stability and physical properties of various polymer/Na‐montmorillonite composites have been synthesized . However, there are no sufficient reports on the literature of the preparation, characterization, and properties of PMAA/halloysite composites synthesized via in situ polymerization.…”

Synthesis and Characterization of Poly(N-Hydroxymethyl Acrylamide)/Na-Montmorillonite Composites

“…The percentage moisture retention was calculated from the difference between the weights of the conditioned and unconditioned samples (i.e. moisture retention%= (W2-W1)/W1 x 100, where W1 and W2 are the weights of the conditioned and unconditioned samples, respectively) (5,11,12).…”