Fundamental properties and potential applications of two surfactant groups produced from renewable resources

Surface-active substances – also known as surfactants – are among the largest product groups in the chemical industry. Due to their versatile use, it is hard to imagine our everyday life without them. Since the dynamics of interfacial adsorption is crucial for the effectiveness of these substances in many applications – such as in the food, detergent, pharmaceutical and cosmetics industries, biochemistry, environmental technology, and others, like firefighting – the use of surfactants in the chemical industry is becoming increasingly important. This work investigated the dynamic surface tensions of surfactants from optimized, innovative manufacturing processes in addition to the most important thermodynamic parameters, such as the CMC (critical micelle concentration) and the HLB value (hydrophilic-lipophilic-balance) and compared the results with a number of commercial products manufactured from fossil raw materials. Given the negative consequences that petroleum-based mass production of surfactants has on the ecosystem, the development of new surfactants today places emphasis on the use of renewable raw materials and alternatives to fossil synthetic building blocks. Two novel product classes were available to us for physicochemical investigation; the first one was synthesized by Covestro by catalytic copolymerization of ethylene oxide (EO) and carbon dioxide (CO2), and the second one by Biosid from natural raw materials such as vegetable oils and yeast proteins. Based on just a few properties and key data, it is now easy to judge whether a surfactant should be used and for what purpose, by comparing them with important characteristics of known surfactants. In addition to the thermodynamically controlled adsorption and distribution equilibria, the dispersion and wetting behavior also play an important role in the use of surfactants. The use of CO2 as a building block could, at least partially, replace the frequently used ethylene oxide, which causes one of the largest CO2 emissions of basic chemicals. By replacing one ethylene oxide unit with a CO2 unit, the molecules become somewhat more hydrophobic, which is reflected in a slight reduction of the HLB value and, above all, a lowering of the critical micelle concentration (CMC). The great similarity with the classic products will greatly simplify their replacement by the CO2-containing surfactants. The great similarity with conventional products will simplify their replacement by CO2-containing surfactants. Also, natural raw materials such as vegetable oils enable, on the one hand, the production of more environmentally friendly surfactants with complete degradability in only a few days and, on the other hand, environmental applications such as soil remediation or water decontamination. For these reasons, these new surfactants are still considered special products, but they will soon qualify as versatile and flexible in application.

Author dc:creator

• Tupinamba Lima, Michelle

Advisor dc:contributor.advisor

• Schomäcker, Reinhard

Licence dc:rights.uri

• http://rightsstatements.org/vocab/InC/1.0/

Language dc:language.iso

en

Identifier URI

http://dx.doi.org/10.14279/depositonce-12744

OAI identifier oai:identifier

oai:depositonce.tu-berlin.de:11303/13971