Ionic Liquid as Surfactant Agent of Hydrotalcite: Influence on the Final Properties of Polycaprolactone Matrix

Abstract

This paper reports the surface treatment of layered double hydroxide (LDH) by using ionic liquid (IL) composed of phosphonium cation combined with 2-ethylhexanoate (EHT) counter anion as surfactant agent. Then, different amounts (1, 3, 5 and 7 wt %) of thermally stable organically modified LDH (up to 350 • C) denoted LDH-EHT were incorporated into polycaprolactone (PCL) matrix by mechanical milling. The influence of LDH-EHT loading has been investigated on the physical properties, such as the thermal and barrier properties, as well as the morphologies of the resulting nanocomposites. Thus, intercalated or microcomposite morphologies were obtained depending on the LDH-EHT loading, leading to significant reduction of the diffusion coefficient respect to water vapor. The modulation of barrier properties, using low functionalized filler amount, is a very important aspect for materials in packaging applications.

Effect of Polymer Demixed Nanotopographies on Bacterial Adhesion and Biofilm Formation

“…It can however, be hypothesised that due to higher solubility of PMMA in chloroform the PCL deposits first on the substrate, which is in agreement with the work carried out by Khattak et al on PCL/PMMA blends [25]. PMMA has a greater surface energy (PCL: 30.8 mN/m, PMMA: 41.0 mN/m) [45,46] and higher molecular weight (PCL: 45 kDa, PMMA: 380 kDa) so it is hypothesised that the initial kinetic arrangement is most likely thermodynamically unstable and may result in a rearrangement of PCL to the surface.…”

“…The closer the values of a polymer to that of its solvent generally indicates better solubility (PS≈PMMA>PCL in chloroform). In PS / PCL blends, the more soluble PS segregates to the surface even after curing at 80 • C, despite having a higher surface energy (PS: 40.7 mN/m, PCL: 30.8 mN/m) [41,44,45] and despite the entropic penalty it incurs being the higher molecular weight component (PS: 280 kDa, PCL: 45 kDa). A possible explanation for this is that the pre-cleaning of the glass substrates renders the surface hydrophilic, thereby having a higher affinity for the more polar PCL [41].…”

Influence of Ethylene Oxide Content in Nonionic Surfactant to the Hydrolysis of Reactive Dye in Silicone Non-Aqueous Dyeing System

“…When the EO chain was shorter in the molecular structure of surfactant, a stable interfacial membrane could be formed at the interface between water and siloxane [38]. And more of surfactants would adsorb to the surface of micelles, with the result that more reactive dyes were aggregated near micelles, which would form the intramolecular or intermolecular hydrogen bond between the dyes and the surfactants [19,39,40]. However, when the EO chain was increased in the molecular structure of nonionic surfactants, the solubility of surfactants in aqueous solution would increase.…”

“…Meanwhile, dye was solubilized primarily as the monomer micelle at a concentration below critical micelle concentration (CMC). If the concentration of surfactant was below CMC, surfactant mainly serves as a dispersant [19]. Chen K. [20] studied the interactions between multi-anionic surfactants and direct dyes with spectrophotometric method, and the surfactants effects on the dyeing of cotton fabrics were also investigated.…”

Ionic Liquid-Nanostructured Poly(Methyl Methacrylate)

“…ILs are organic salts that exhibit a low melting temperature, good ionic conductivity, good thermal stability, and negligible vapor pressure [26,27,28]. In fact, ILs were commonly used as suitable compounds for compatible agents of polymer blends [29,30,31,32], such as (nano)structuration agents of fluorinated polymers and copolymers [33,34], non-conventional initiators of epoxy reactive systems [35,36], as well as surfactants or plasticizers of different polymers [37,38,39,40]. Recent works reported the advantages ILs used as plasticizers in synthetic and biosourced polymers.…”