Synthesis, Micellization Behavior And Alcohol Induced Amphipathic Cellulose Film Of Cellulose-based Amphiphilic Surfactant

This paper presents a novel preparation method of the cellulose-based amphiphilicsurfactant and the amphiphilic cellulose membrane aggregated by cellulose-basedamphiphilic surfactant with adding alcohol induced action.In this research, we employed cotton cellulose as raw material which degree ofpolymerization was3961. The native cotton cellulose was tailored to cellulose segment inionic liquid1-butyl-3-methylimidazolium chloride, and its average degree ofpolymerization fell down from3691to141. The native cellulose was successfully tailoredto cellulose segments with lower DP and PDI of1.38, which was close to the native cottoncellulose. The molecular weight distribution of cellulose and cellulose segment wasrecorded with the method of gel permeation chromatography (GPC). The cellulose segmentwith polydispersity index of1.38was selected as the raw material, and then thehydrophobic esterification was carried out by the graft polymerization of theε-caprolactone (ε-CL) monomer on the hydroxyl group of cellulose, as well ashydrophilic sulphonation was performed with sulfamic acid and neutralization with sodiumhydroxide. The molecular structure of surfactant was confirmed by FT-IR, and its surfaceactive properties were investigated by Wilhelmy plate method and Steady-statefluorescence probe method. In the process of hydrophobic modification, when thetemperature was120°C, the reaction time was25h and the mole ratio of ε-caprolactone andcellulose hydroxyl group was5:1,10:1and15:1, the grafting rate reached to18.61%,25.40%and30.26%, respectively. In the process of hydrophilic modification, when thereaction temperature was60°C, the reaction time was6h and the mole ratio ofAGU/NH2SO3H was1:2, the degree of substitution of sodium cellulose sulfate gave amaximum of0.24. Cellulose-based amphiphilic surfactants could make the solution withlow interfacial tension of48.62mN/m and its cmc value was0.65wt%when the graftingratio of cellulose-g-PCL was25.40%.The amphiphilic cellulose membrane was made by cellulose-based amphiphilicsurfactant cross-linking with glutaraldehyde, which was alcohol induced the hydrophobicchain partitions orientation arranged on the top of the film when alcohol and waterevaporated from solution. The contact angle between a droplet of water and the surface ofmembrane was0owithout the alcohol induced. But contact angle between a droplet of water and the surface of membrane was90.84oafter the induced by alcohol and the surfacefree energy of the alcohol induced cellulose membrane was15.7mJ/m2.