Abstract:
The dependence of the physicochemical properties of cellulose carboxylate/tosylate mixed esters on their molecular structures is reported. The esters employed have a constant degree of substitution (DS) of the tosyl group, DSTosyl = 0.98 and variable DS of the ester group, DSAcyl (ester = acetate, butanoate, hexanoate). These mixed esters do not exhibit glass transition temperatures and decompose before melting. Using perichromic dyes and contact angle measurements of their films, the dependence of the following properties on DSAcyl were investigated: empirical polarity, Lewis acidity and basicity, and hydrophobicity. Most of these properties display a simple dependence on DSAcyl, which reflects the conversion of the hydroxyl- into ester group. These mixed esters were regenerated as uniform microspheres from their solutions in acetone; their adsorption of methylene blue and Sudan IV dyes was studied, and the dye adsorption data correlate with the Lewis basicity and the dispersive component of surface energy.
Reference:
FERREIRA, Daniela Colevati.; BASTOS, Gustavo S.; PFEIFFER, Annett, PETRI, Denise F.S.; HEINZE, Thomas, El SEOUD, Omar A. Cellulose carboxylate / tosylate mixed esters: dependence of their physicochemical properties on the degree of carboxylate substitution. Lenzinger Berichte, v.94, p.43-55, 2018.
Access to the article on the newspaper website:
https://www.lenzing.com/index.php?type=88245&tx_filedownloads_file%5bfileName%5d=fileadmin/content/PDF/03_Forschung_u_Entwicklung/Lenzinger_Berichte_94_2018.pdf
The dependence of the physicochemical properties of cellulose carboxylate/tosylate mixed esters on their molecular structures is reported. The esters employed have a constant degree of substitution (DS) of the tosyl group, DSTosyl = 0.98 and variable DS of the ester group, DSAcyl (ester = acetate, butanoate, hexanoate). These mixed esters do not exhibit glass transition temperatures and decompose before melting. Using perichromic dyes and contact angle measurements of their films, the dependence of the following properties on DSAcyl were investigated: empirical polarity, Lewis acidity and basicity, and hydrophobicity. Most of these properties display a simple dependence on DSAcyl, which reflects the conversion of the hydroxyl- into ester group. These mixed esters were regenerated as uniform microspheres from their solutions in acetone; their adsorption of methylene blue and Sudan IV dyes was studied, and the dye adsorption data correlate with the Lewis basicity and the dispersive component of surface energy.
Reference:
FERREIRA, Daniela Colevati.; BASTOS, Gustavo S.; PFEIFFER, Annett, PETRI, Denise F.S.; HEINZE, Thomas, El SEOUD, Omar A. Cellulose carboxylate / tosylate mixed esters: dependence of their physicochemical properties on the degree of carboxylate substitution. Lenzinger Berichte, v.94, p.43-55, 2018.
Access to the article on the newspaper website:
https://www.lenzing.com/index.php?type=88245&tx_filedownloads_file%5bfileName%5d=fileadmin/content/PDF/03_Forschung_u_Entwicklung/Lenzinger_Berichte_94_2018.pdf
