New gemini surfactants with two azobenzene groups controlled by light irradiation

The synthesis of N,N'-bis (4-alkylazobenzene-4-oxy-2-hydroxypropyl)-N,N,N',N'-tetramethylethylene diammonium methylsulphate (qDAZDA-n series, n = 0, 2, 4, and 8), a new type of symmetric gemini light-sensitive cationic surfactants, has been achieved. The CMC range was extremely low at 5.23-2.17 x 10-4 mN m-1 when in the trans form, and 1.91 x 10-3-4.91 x 10-4 mN m-1 as mixtures with 92% cis isomer. The synthesis was designed to be conducted under mild conditions, such as atmospheric pres-sure, temperatures not exceeding 100 & DEG;C, and solvents that can be easily removed, thus showing promise for industrial applications. Upon exposure to UV light, 92.5% of the trans-qDAZDA-n series underwent conversion to the cis form, and upon exposure to visible light, 69.3-77.3% of the compound was trans-formed back to the trans form. The study conducted contact angle measurements on a hydrophilic media to investigate the wettability of the surfactants. Tests were conducted on the properties of the synthe-sized surfactants, and a comparison was made with two commonly used commercial surfactants, sodium lauryl ether sulfate (SLES-3) and dodecyl benzene sulfonate (DBS). & COPY; 2023 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.

Automated summary

The synthesis of a new type of symmetric gemini light-sensitive cationic surfactants, qDAZDA-n series, has been achieved. The surfactants showed low CMC range and were convertible between trans and cis forms under UV and visible light exposure. Contact angle measurements were conducted to study the surfactants' wettability. The synthesized surfactants were compared with commonly used commercial surfactants, SLES-3 and DBS.