Synthesis and Physico-Chemical Properties of Novel Biocompatible AlkylD-Mannopyranosiduronate Surfactants Derived from Alginate

Integrated Conversion of Lignocellulosic Biomass to Bio-Based Amphiphiles using a Functionalization-Defunctionalization Approach

Concerns over the sustainability and end-of-life properties of fossil-derived surfactants have driven interest in bio-based alternatives. Lignocellulosic biomass with its polar functional groups is an obvious feedstock for surfactant production but its use is limited by process complexity and low yield. Here, we present a simple two-step approach to prepare bio-based amphiphiles directly from hemicellulose and lignin at high yields (29 % w/w based on the total raw biomass and >80 % w/w of these two fractions). Acetal functionalization of xylan and lignin with fatty aldehydes during fractionation introduced hydrophobic segments and subsequent defunctionalization by hydrogenolysis of the xylose derivatives or acidic hydrolysis of the lignin derivatives produced amphiphiles. The resulting biodegradable xylose acetals and/or ethers, and lignin-based amphiphilic polymers both largely retained their original natural structures, but exhibited competitive or superior surface activity in water/oil systems compared to common bio-based surfactants.

Cascading One-Pot Synthesis of Biodegradable Uronic Acid-Based Surfactants from Oligoalginates, Semi-Refined Alginates, and Crude Brown Seaweeds

The present article describes a one-pot and cascade mode process using biocompatible/biodegradable reagents, for simply obtaining surfactant compositions comprising mixtures of d-mannuronic acid and l-guluronic acid directly from oligoalginates or semi-refined alginates (mixtures of alginate, cellulose, hemicellulose, laminaran, and fucan). Simple treatments of partial purification of the reaction crudes (elimination of the salts and/or the residual fatty alcohols) or isolation of the surfactant compositions result in sugar-based compounds having performance levels appropriate to applications in detergency. In addition, the challenging extension of this cascading one-pot synthesis technology to crude milled brown seaweeds was successfully carried out to provide promising surface-active compositions made up of alkyl uronate and alkyl glycoside monosaccharides.

Transformation of Pectins into Non-Ionic or Anionic Surfactants Using a One-Pot and Cascade Mode Process

The present article describes the one-pot synthesis of double- and single-tailed surfactants by a cascade process that involves the hydrolysis/butanolysis of pectins into butyl galacturonate monosaccharides followed by transesterification/transacetalisation processes with fatty alcohols, and subsequent aqueous basic and acid treatments. The cascade mode allows the depolymerisation to proceed more efficiently, and the purification conditions are optimised to make the production of single-tailed surfactants more manufacturable. These products in a pure form or as mixtures with alkyl glycosides resulting from butanolysis and transglycosylation of pectin-derived hexoses, exhibit attractive surface-tension properties, especially for the n-oleyl ᴅ-galactosiduronic acid products. In addition, a readily biodegradability and an absence of aquatic ecotoxicity are shown for the galacturonic acid derivatives possessing an oleyl alkyl chain at the anomeric position.

Study on the synthesis and properties of an eco-friendly sugar-based anionic–nonionic surfactant

An eco-friendly surfactant (DAGA-ES) was successfully synthesized and characterized by electrospray ionization-time of flight mass spectrography (ESI-TOFMS),¹H nuclear magnetic resonance (¹HNMR) and Fourier transform infrared spectrometer (FT-IR).

Alkyl-imidazolium glycosides: non-ionic-cationic hybrid surfactants from renewable resources

A series of surfactants combining carbohydrate and imidazolium head groups were prepared and investigated on their assembly behavior. The presence of the imidazolium group dominated the interactions of the surfactants, leading to high CMCs and large molecular surface areas, reflected in curved rather than lamellar surfactant assemblies. The carbohydrate, on the other hand, stabilized molecular assemblies slightly and reduced the surface tension of surfactant solutions considerably. A comparative emulsion study discourages the use of pure alkyl imidazolium glycosides owing to reduced assembly stabilities compared with APGs. However, the surfactants are believed to have potential as component in carbohydrate based surfactant mixtures.

Monolayer lipid membrane-forming dissymmetrical bolaamphiphiles derived from alginate oligosaccharides

New dissymmetrical neutral-cationic or anionic-cationic alpha,omega-diamido bolaamphiphiles have been synthesized in which the polar headgroups are derived from alginate and glycine betaine and which exhibit monolayer lipid membrane vesicles, large lamellae and rods.