Mechanistic Aspects of Clay Intercalation with Amphiphilic Poly(styrene-co-maleic anhydride)-Grafting Polyamine Salts

Abstract

The ionic exchange reaction of the smectite clays was affected by using a series of polymeric amine salts, synthesized by grafting poly(oxyalkylene)-diamines (POA-amine) onto poly(styrene-co-maleic anhydrides) (SMA). The comb-branched polyamines, comprised of a hydrophobic SMA backbone and multiple amine pendants, are amphiphilic in nature and capable of reducing the toluene/H 2 O interfacial tension (from 36 to 4 mN/m at 10 -3 wt % concentration). After acidification to cationic amines (-NH 3 + Cl -), the polyamines increased solubility in water and effectiveness for the clay intercalation. Depending on the structural variation and their amphiphilic property, the SMA-derived polyamines may intercalate with sodium montmorillonite to yield the organoclays with a broad range of XRD basal spacing from 12.9 to 78.0 Å. The intercalation profile is suspected to proceed with a critical d spacing expansion, due to hydrophobic phase separation from the embedded organics in the gallery confinement. The variations of hybrid basal spacing, TGA degradation pattern, and DSC analyses indicated the presence of at least two different types of intercalated hybrids. The finding on clay intercalating mechanism could lead to the synthesis of new organoclays for suiting versatile applications.

Efficacy and safety of nanohybrids comprising silver nanoparticles and silicate clay for controlling Salmonella infection

“…19 The SMA-AgNPs were prepared chemically by reducing Ag salts into NPs by NaBH 4 . 16 The excess Ag ions and free SMA were further removed by dialysis.…”

Influence of Reaction Conditions on the Grafting Pattern of 3-Glycidoxypropyl trimethoxysilane on Montmorillonite

“…According to the Bragg's equation (nλ = 2dsinθ), the basal spacing of n = 1 was calculated on the basis of the observed n = 2, 3 and so on. 21 Unmodified MMT shows a peak at 2θ = 7.8° corresponding to an interlayer spacing of 1.13 nm (Table 4). After modifications with 3GTO, the interlayer spacing exhibits a little increase (about 1.26 nm) when the silane concentration in feed is 1.5 mmol/ g regardless of the reaction time.…”

Hierarchical synthesis of silver nanoparticles and wires by copolymer templates and visible light

“…The preparation of POE-amine graft SMA2000 copolymers (SMA-POE) was reported previously in our laboratory [42][43][44]. Typical procedures for preparing POE-amine grafted SMA2000 at 1:1 MA/NH 2 molar ratio are described below.…”

“…The synthesis [42], amphiphilicity [43] and pH-thermoresponse [44] of grafting poly(oxyethylene) [POE] segmented monoamine onto SMA have been extensively studied in our laboratory. The copolymer possesses multiple amidoacid polar functionalities for association with Ag + .…”