Alkyl di-/tri-/tetraoxyethyl β-D-xylopyranosides as derivatives of alkyl xylosides are a class of non-ionic sugarbased surfactants. They were stereoselectively synthesized by the Helferich method. Their properties including hydrophilic− lipophilic balance number, water solubility, surface property, foam property, emulsifying property, and thermotropic liquid crystal property were mainly investigated. The results showed that their water solubility decreased with increasing the alkyl chain length and increasing the number of the oligooxyethyl fragment. The critical micelle concentration had a monotonous decreasing trend with increasing the alkyl chain length. Nonyl di-/tri-/tetraoxyethyl β-D-xylopyranosides [−(OCH 2 CH 2 ) m −, where m = 2, 3, and 4] exhibited the most excellent foaming ability and foam stability. In the n-octane/water system, dodecyl tetraoxyethyl β-D-xylopyranosides and tetradecyl tetraoxyethyl β-D-xylopyranosides had the strongest emulsion ability. In addition, some alkyl di-/tri-/tetraoxyethyl β-D-xylopyranosides had thermotropic liquid crystal properties. Such sugar-based surfactants, alkyl di-/tri-/tetraoxyethyl β-D-xylopyranosides, will be expected to develop for a variety of practical application.

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In order to improve the water solubility of sugar‐based surfactants, alkyl β‐d‐xylopyranosides, novel sugar‐based surfactants, 1,2‐trans alkoxyethyl β‐d‐xylopyranosides, with alkyl chain length n = 6–12 were stereoselectively prepared by the trichloroacetimidate method. Their properties including hydrophilic–lipophilic balance (HLB) number, water solubility, surface tension, emulsification, foamability, thermotropic liquid crystal, and hygroscopicity were investigated. The results indicated that their HLB number decreased with increase of alkyl chain, the water solubility improved since the hydrophilic oxyethene (─OCH2CH2─) fragment was introduced. The dissolution process was entropy driven at 25–45 °C for alkyl chain length n = 6–10. Octyloxyethyl β‐d‐xylopyranoside had the best foaming ability. Nonyloxyethyl β‐d‐xylopyranoside had the best foam stability and the emulsifying ability was better in toluene/water system than in rapeseed oil/water system. The surface tension of in aqueous solution dropped to 27.8 mN m−1 at the critical micelle concentration, and it also showed the most distinct thermotropic liquid phases with cross pattern texture upon heating and the fan schlieren texture on cooling. Hexyloxyethyl β‐d‐xylopyranoside possessed the strongest hygroscopicity. Based on the effective improvement of water solubility, the prepared alkoxyethyl β‐d‐xylopyranosides showed excellent surface activity and are expected to develop their practical application as a class of novel sugar‐based surfactants.

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