Journal
MOLECULES
Volume 26, Issue 4, Pages -Publisher
MDPI
DOI: 10.3390/molecules26040863
Keywords
extended anionic surfactant; branched chain; polymethylmethacrylate; contact angle; adsorption
Funding
- National Key Research and Development Program [2019YFA0708700]
- PetroChina Innovation Foundation [2019D-5007-0209]
Ask authors/readers for more resources
The adsorption behaviors of different extended anionic surfactants on the PMMA surface were studied, showing that the special properties of PO groups can enhance polar interactions and allow gradual adsorption on the PMMA surface. Before the critical micelle concentration, the adsorption amounts of the surfactants at the PMMA-liquid interface were approximately one third of those at the air-liquid interface.
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.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available