Authors: J Peydecastaing C VacaGarcia E Borredon
Publish Date: 2011/04/11
Volume: 18, Issue: 4, Pages: 1023-1031
Abstract
Cellulose powder was acylated with mixtures containing acetic fatty and aceticfatty anhydrides to form aceticfatty cellulose esters The total degree of substitution DS of the mixed cellulose esters MCE ranged from 2 × 10−2 to 292 MCE were characterized by their interactions with water Static contact angles with water were measured on a regular smooth surface The values found were dependent on the fatty acyl content and independent of the acetyl content In the case of aceticoleic cellulose esters the minimum DS of the oleoyl moiety required to obtain permanent water repellency was 3 × 10−4 The microporosity of the samples may account for this exceptional hydrophobic character Nevertheless water vapor adsorption measurements on powder samples revealed only a limited increase in hydrophobicity of the MCE compared to cellulose acetate with the same acetyl content It was thus demonstrated that water repellency and vapor water adsorption are not correlated
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