Carbohydrate-based surfactants

In polymer applications derivatives of oils and fats, such as epoxides, polyols and dimerizations products based on unsaturated fatty acids, are used as plastic additives or components for composites or polymers like polyamides and polyurethanes. In the lubricant sector oleochemically-based fatty acid esters have proved to be powerful alternatives to conventional mineral oil products. For home and personal care applications a wide range of products, such as surfactants, emulsifiers, emollients and waxes, based on vegetable oil derivatives has provided extraordinary performance benefits to the end-customer. Selected products, such as the anionic surfactant fatty alcohol sulfate have been investigated thoroughly with regard to their environmental impact compared with petrochemical based products by life-cycle analysis. Other product examples include carbohydrate-based surfactants as well as oleochemical based emulsifiers, waxes and emollients. 

As a new approach to the preparation of water-soluble polymers in inverse miniemulsions, a redox initiation system consisting of ceric ions and carbohydrate-based surfactant Span 60 as a reducing agent has been successfully used for the... 

Furthermore, the results achieved sowed the seeds for future developments which are under investigation in ENSCR/CEVA laboratories (1) the exploration of additional marine algae as sources of innovative carbohydrate-based materials and (2) the possibility of exploiting intact oligoalginates as original hydrophilic moieties for the production of new surfactants and glycopolymers. 

FI. Kamitakahara, F. Nakatsubo, and D. Klemm, New class of carbohydrate-based non-ionic surfactants Diblock co-oligosaccharides of tri-O-methylated and unmodified celloohgosaccharides. Cellulose, 14 (2007) 513-528. 

J. E. Klijn, M. C. A. Stuart, M. Scarzello, A. Wagenaar, J. B. F. N. Engberts, pH-dependent phase behaviour of carbohydrate-based gemini surfactants. The effects of carbohydrate stereochemistry, head group hydrophilicity, and nature of the spacer, J. Phys. Chem. B, 2007, 111, 5204-5211. 

The expanding interest in alternative surfactants made from renewable resources has been driven somewhat by the perceived environmental benefits that these materials have over those from nonrenewable sources. While it is true that these aspects have been a significant driver in the level of interest in carbohydrate-based surfactants in particular, the unique physicochemical properties of these materials offer significant advantages over other materials in some applications. 

These points apply also to the subset of carbohydrate-based surfactants that comprises a fatty acid hydrophobic group attached to a sugar-based head group, sugar fatty acid esters. 

Klein J, Kunz M, Kowalczyk J (1990) Poly(vinylsaccharide)s.7. New surfactant polymers based on carbohydrates. Makromol Chem Phys 191(3) 517-528... 

Carbohydrate-based surfactants are the final result of a product concept that is based on the greatest possible use of renewable resources. While the derivatisation of fats and oils to produce a variety of different surfactants for a broad range of applications has a long tradition and is well established [1, 2], the production of surfactants based on fats and oils and carbohydrates on a bigger industrial scale is relatively new. Today the most important carbohydrate-based surfactants are alkyl polyglycosides, sorbitan esters and sucrose esters [3]. 

Surfactants Based on Carbohydrates and Proteins for Consumer Products and Technical Applications 69 Table 4.3 Selected suppliers and main fields of application for carbohydrate-based surfactants... 

Ruback, W. and Schmidt, S. (1996) Alkyl polyglucoside, a carbohydrate-based surfactant, in Carbohydrates as Organic Raw Materials III (eds H. van Bekkum, H. Roper and A. G. J. Vorhagen), Wiley-VCH Verlag GmbH, Weinheim, pp. 231-253. 

In anticipation of a more balanced discussion on renewable and fossil resources for surfactants a consensus on the coexistence of petrochemically derived products and products based on, for instance, oils, fats, and carbohydrates can be predicted. 

The development of surfactants based on carbohydrates and oils is the result of a product concept based on the exclusive use of renewable resources. In industry, saccharose (sucrose), glucose and sorbitol, which are available in large amounts and at attractive prices, are used as the preferred carbohydrate raw materials. 

Pfannemtiller et al. showed that it is possible to obtain carbohydrate-containing amphiphiles with various alkyl chains via amide bond formation. For this, mal-tooligosaccharides were oxidized to the corresponding aldonic acid lactones, which could subsequently be coupled to alkylamines [128-136]. Such sugar-based surfactants are important industrial products with applications in cosmetics, medical applications etc. [137-139]. The authors were also able to extend the attached mal-tooligosaccharides by enzymatic polymerization using potato phosphorylase, which resulted in products with very interesting solution properties [140, 141]. 

Since nonionic carbohydrate-derived surfactants are available in sufficient quantities and at competitive costs at present, anionic versirais of these chemicals such as carboxylates, sulfates, and phosphates are less common. Until now there have been only a few products (anionic derivatives of APG) established in the market [29]. Indeed, the derivatization of neutral sugar-based surfactants to furnish anionic compounds is not easy at a competitive cost with the sulfate (alcohol ether sulfates, AES) and sulfonate (linear alkylbenzene sulfcaiates, LAS) surfactants derived from petrochemicals. Within this context, uronate derivatives possessing carboxylate functionality represent attractive starting materials for the preparation of negatively charged surfactants. 

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