TY - JOUR

T1 - Dry, hydrophobic microfibrillated cellulose powder obtained in a simple procedure using alkyl ketene dimer

AU - Yan, Yutao

AU - Amer, Hassan

AU - Rosenau, Thoma

AU - Zollfrank, C.

AU - Dörrstein, Jörg

AU - Jobst, Cornelia

AU - Zimmermann, Tanja

AU - Keckes, Jozef

AU - Veigel, Stefan

AU - Gindl-Altmutter, Wolfgang

AU - Li, Jianzhang

N1 - cited By 1

PY - 2016

Y1 - 2016

N2 - In order to produce dry and hydrophobic microfibrillated cellulose (MFC) in a simple procedure, its modification with alkyl ketene dimer (AKD) was performed. For this purpose, MFC was solvent-exchanged to ethyl acetate and mixed with AKD dissolved in the same solvent. Curing at 130 °C for 20 h under the catalysis of 1-methylimidazole yielded a dry powder. Scanning electron microscopy of the powder indicated loss in nanofibrillar structure due to aggregation, but discrete microfibrillar structures were still present. Water contact angle measurements of films produced from modified and unmodified MFC showed high hydrophobicity after AKD treatment, which persisted even after extraction with THF for 8 h. The hydrophobized MFC was characterized by Fourier transform infrared spectroscopy, nuclear magnetic resonance and X-ray analysis. In summary, strong indications for the presence of AKD on the surface of MFC before and after extraction with solvent were found, but only a very small amount of covalent β-ketoester linkages between the modification agent and cellulose was revealed.

AB - In order to produce dry and hydrophobic microfibrillated cellulose (MFC) in a simple procedure, its modification with alkyl ketene dimer (AKD) was performed. For this purpose, MFC was solvent-exchanged to ethyl acetate and mixed with AKD dissolved in the same solvent. Curing at 130 °C for 20 h under the catalysis of 1-methylimidazole yielded a dry powder. Scanning electron microscopy of the powder indicated loss in nanofibrillar structure due to aggregation, but discrete microfibrillar structures were still present. Water contact angle measurements of films produced from modified and unmodified MFC showed high hydrophobicity after AKD treatment, which persisted even after extraction with THF for 8 h. The hydrophobized MFC was characterized by Fourier transform infrared spectroscopy, nuclear magnetic resonance and X-ray analysis. In summary, strong indications for the presence of AKD on the surface of MFC before and after extraction with solvent were found, but only a very small amount of covalent β-ketoester linkages between the modification agent and cellulose was revealed.

U2 - 10.1007/s10570-016-0887-0

DO - 10.1007/s10570-016-0887-0

M3 - Article

VL - 23.2016

SP - 1189

EP - 1197

JO - Cellulose

JF - Cellulose

SN - 0969-0239

IS - 2

ER -