Alkyl polyglycosides have superior performance and great potential for development

2017-11-29 10:59:32

Conventional surfactants have a low molecular weight and generally do not completely cover the surface area of the particles, and are also easily transferred from the surface, resulting in problems such as flocculation generation and increased particle adhesion during storage. In general, the dispersibility of a surfactant depends on two factors, the molecular weight and the type of lipophilic group. In order to improve the long-term stability of the formulation, it can be seen that the action of the water-based dosage form surfactant as an emulsifier and a dispersing agent is increasing.

This is because the oleophilic surfactant having a large molecular weight diffuses to the surface of the particle at a slower rate, but its adsorption ability is strong, and it is difficult to transfer and fall off from the surface, thereby providing long-term stability.

Alkyl polyglucosides (APGs) are a new class of nonionic surfactants that began industrialization in the 1990s. The alkyl polyglucoside is a mixed product obtained by the hemiacetal hydroxyl group of a glucose and a fatty alcohol hydroxyl group, which is lost by water under the catalysis of an acid (monosaccharide, diglucoside, triglycoside, etc., and is also called an alkyl polyglycoside). Its molecular structure is generally in the form of RO(G)n, wherein the saccharide unit is a hydrophilic group, and the long-chain or branched-chain alkane is an oleophilic group. Alkyl polyglucosides are hygroscopic solids, pure alkyl glycosides are white powders, and industrial products are pale yellow or light yellow due to impurities. The alkyl glycoside is dissolved in water and the product is typically formulated as a 50 to 70% aqueous solution.

Compared with other surfactants, alkyl polyglucoside surfactants have the characteristics of low surface tension, strong detergency, stability in alkaline environment, excellent compounding performance, and low irritation to skin and low toxicity. It is prepared with glucose and fatty alcohol, so it has good biodegradability and no pollution to the environment. Its superior performance and great potential for development are widely used in the fields of washing, cosmetics and food. As a new environmentally friendly surfactant, in recent years, research on alkyl glycosides has become one of the most active research fields and development priorities of surfactants.

At present, the synthesis of alkyl glycosides by transglycosylation is mainly to improve the catalyst, and the catalysts with better effect are as follows, such as HCl, H:S0. And H, P04, etc.; sulfonic acid catalysts, such as p-toluenesulfonic acid, alkylbenzenesulfonic acid, p-toluenesulfonic acid pyridinium salt; in addition to supported heteropolyacids and strong acid type ion exchange resins; Acid or several acids co-catalyzed. With the constant efforts of researchers,