Wettability of a Polymethylmethacrylate Surface by Extended Anionic Surfactants: Effect of Branched Chains

Abstract

The adsorption behaviors of extended anionic surfactants linear sodium dodecyl(polyoxyisopropene)4 sulfate (L-C12PO4S), branched sodium dodecyl(polyoxyisopropene)4 sulfate (G-C12PO4S), and branched sodium hexadecyl(polyoxyisopropene)4 sulfate (G-C16PO4S) on polymethylmethacrylate (PMMA) surface have been studied. The effect of branched alkyl chain on the wettability of the PMMA surface has been explored. To obtain the adsorption parameters such as the adhesional tension and PMMA-solution interfacial tension, the surface tension and contact angles were measured. The experimental results demonstrate that the special properties of polyoxypropene (PO) groups improve the polar interactions and allow the extended surfactant molecules to gradually adsorb on the PMMA surface by polar heads. Therefore, the hydrophobic chains will point to water and the solid surface is modified to be hydrophobic. Besides, the adsorption amounts of the three extended anionic surfactants at the PMMA–liquid interface are all about 1/3 of those at the air–liquid interface before the critical micelle concentration (CMC). However, these extended surfactants will transform their original adsorption behavior after CMC. The surfactant molecules will interact with the PMMA surface with the hydrophilic heads towards water and are prone to form aggregations at the PMMA–liquid interface. Therefore, the PMMA surface will be more hydrophilic after CMC. In the three surfactants, the branched G-C16PO4S with two long alkyl chains exhibits the strongest hydrophobic modification capacity. The linear L-C12PO4S is more likely to densely adsorb at the PMMA–liquid interface than the branched surfactants, thus L-C12PO4S possesses the strongest hydrophilic modification ability and shows smaller contact angles on PMMA surface at high concentrations.

How to Regulate the Migration Ability of Emulsions in Micro-Scale Pores: Droplet Size or Membrane Strength?

“…Ge [ 16 ] studied the IFT of sulfate-based extended surfactant (NPP 3 S) and different weak base compound systems, and found that it has a good synergistic effect with Na 2 CO 3 in reducing the oil-water IFT. Jiang [ 17 ] explored the wettability of anionic nonionic surfactants on polymethyl methacrylate and investigated the influence of alkyl branching on the adsorption behavior.…”

Wetting effect of branched anionic Gemini surfactant aqueous solution on PMMA surface

“…The wetting phenomenon on solid surfaces has received considerable attention in a variety of fields such as adhesion, oil extraction, flotation, membrane distillation, washing and lubrication. [1][2][3][4][5] Surfactants play a crucial role in regulating the wetting properties of solid surfaces. Researchers have been continuously innovating the structure of surfactants to achieve better wetting performance.…”

“…Researchers have been continuously innovating the structure of surfactants to achieve better wetting performance. Over time, surfactants have evolved from single-chain to various special structures including alkylbranched double-zwitterionic head Gemini surfactants, 6,7 double-chained surfactants with dual hydrophobic chains, 8 inserted functionalized monomeric units, 4 amphoteric ions, 9 and alkyl-branched structures. 4 Among these, Gemini and double-chained surfactants have recently garnered much focus.…”

“…Over time, surfactants have evolved from single-chain to various special structures including alkylbranched double-zwitterionic head Gemini surfactants, 6,7 double-chained surfactants with dual hydrophobic chains, 8 inserted functionalized monomeric units, 4 amphoteric ions, 9 and alkyl-branched structures. 4 Among these, Gemini and double-chained surfactants have recently garnered much focus. In particular, Gemini surfactants and double-chained surfactants have demonstrated significant progress in the wetting behaviour on the surface of polymethyl methacrylate (PMMA) and are thus worth studying.…”

Synthesis, characterization, and functional evaluation of branched dodecyl phenol polyoxyethylene ethers: a novel class of surfactants with excellent wetting properties

“…Compared with linear surfactants, branched surfactants exhibit preferable wetting ability toward potential application, which was mainly caused by the difference in diffusion rate. [18][19][20] Although high-branched alkyl tails may lead to poor biodegradability, branched surfactants with limited short side-chains have been testied to have negligible effect on their biodegradability. 21 With respect to the linear isomer, a branched alkyl amine oxide surfactant (C 10 DAO-branched) showed the ability to form concentrated solutions without generating lyotropic liquid crystals 22 or to tune supramolecular aggregation upon pH stimuli.…”