Modification of Montmorillonite with Alkyl Silanes and Fluorosurfactant for Clay/fluoroelastomer (FKM) Nanocomposites

Abstract

The main objective of the present work was to functionalize nanoclays with organosilanes and surfactant in order to facilitate the dispersion of the nanofillers in the host fluoroelastomer (FKM) polymer matrix. Better dispersion was achieved by improving interaction between the clay polymer nanocomposite (CPN) constituents. The first part of this study investigated modification of montmorillonite (Mnt) using different saturated and unsaturated alkyl silanes and an alkyl hydrocarbon ammonium quaternary surfactant. Silicon magic angle spinning nuclear magnetic resonance spectroscopy, thermal gravimetric analysis (TGA), elemental analysis, X-ray diffraction (XRD), and Fourier transform infrared spectroscopy were used to characterize the silane-grafted clays. Results indicated that the amount of silane grafted depended on the specific structure of the silane. Silane-grafted Mnt was also modified with ionic surfactants intercalated between the clay layers. A 169% increase in the clay basal spacing (from initial spacing of 10.0 Å to 26.9 Å ) was achieved. The second part of the study successfully synthesized FKM nanocomposites containing custom-functionalized Mnt, with the aim of producing reinforced highperformance materials. The effects of clay modification on the morphology and thermal properties of the CPN were studied using XRD, TGA, scanning electron microscopy, and transmission electron microscopy. The CPN made with the modified clay exhibited greater thermal stability than the CPN of the commercially available modified Mnt, with a degradation onset point~40ºC higher.

Synthesis and characterization of nylon 6 polymer nanocomposite using organically modified Indian bentonite

“…The co-surfactant locked in the interlayer of bentonite was synthesized using two organic moieties namely CTAB and APTES. Both organic moieties were incorporated by cross modification approach [21][22][23]. Exactly 5 g of the AMSB sample dispersed in 200 ml of Milli Q water, and the same ideal process was followed to cross interaction with CTAB, washing and drying of material.…”

“…Recently several attempts have been reported for the improvement of mechanical and thermal stability of polymer composites by using thermally or structurally stable organo-bentonite in unmodified polymer such as nylon 6, nylon 66, polyvinyl alcohol, polypropylene, polyvinylchloride, butadiene, styrene polymer, polymethyl methacrylate etc., [14][15][16][17][18][19][20]. Recently novel approaches are reported for the 2:1 types of expandable clay minerals where modifications are reported using two organic modifiers in which already modified clay minerals again undergoes modification with surfactant or silane functional moieties to obtained co-surfactant locker system (CLOM) [21]. Recently Katia and coworkers functionalized saponite clay with the surfactant n-hexadecyltrimethylammonium bromide (CTAB) and/or with the alkoxysilane 3-aminopropyltriethoxysilane (APTS) and investigated how clay functionalization affected on the capacity of saponite to adsorb caffeine [22].…”

Fabrication and characterization of nanoclay-reinforced thermoplastic composite films

“…22,23 The existence of the amorphous phase, which reduces the rigidity of materials, in the surfactant-silanized clay powder can be another possible reason for the lower E' values. 17,24 Therefore, the maximum E' values are attributed to the strong bonding formed between the host polymer and the silanized nanoclay.…”

“…Based on the XRD results, an approximately 169 % increase in the basal spacing was found with reasonably good dispersion. 17 The main motivation of this study is the application of an organophilic modification and silane surface treatment to the same composite films to combine their synergetic effects. Thus, two modification methods (silane agent treatment or silane agent+surfactant application joint modification) with three different clay concentrations (0.5, 1 and 2) % were studied.…”

Improving mechanical and electrical properties of fluoroelastomer nanocomposites by incorporation of low content of reduced graphene oxide via fast evaporation mixing

“…Fluoroelastomer (FKM), containing C‐F pendant groups, exhibits remarkable thermal and chemical resistance. In order to bring its potential into full play and meet the severe end‐use requirements, many fillers are used to improve the properties of FKM, such as montmorillonite (MMT) , carbon nanotubes , halloysites , and Kevlar fibers . In recent years, some research has focused on FKM/graphene composites .…”