Chair for Biogenic Polymers, TUM Campus Straubing for Biotechnology and Sustainability, Technical University of Munich, Straubing, Germany.
Institute of Physical and Theoretical Chemistry, University of Regensburg, Regensburg, Germany.
Carbohydr Polym. 2018 Jul 15;192:159-165. doi: 10.1016/j.carbpol.2018.03.045. Epub 2018 Mar 18.
We report on a method for the preparation of cellulose/chitin composite materials from the ionic liquid 1-butyl-3-methylimidazolium acetate and γ-valerolactone as a biosourced sustainable co-solvent. Element analysis and attentuated total reflectance Fourier transform infrared spectroscopy show that the average degree of acetylation of chitin in the composite materials was around 82.5%. This indicates that chitin is not deacetylated to chitosan during the dissolution process. The X-ray diffraction results show that the degree of crystallinity of the composite materials increases from amorphous to 59% with increasing chitin concentration accompanied by a developing crystallite size up to 3 nm. Mechanical testing yielded a maximum tensile stress of 4.7 MPa, an elastic modulus of 27.4 MPa and a breaking elongation of 78.7% for the composites with 80 wt% chitin. In addition, water contact angle measurements indicated that the presence of chitin rendered the materials more hydrophobic.
我们报告了一种从离子液体 1-丁基-3-甲基咪唑醋酸盐和γ-戊内酯作为生物源可持续共溶剂制备纤维素/壳聚糖复合材料的方法。元素分析和衰减全反射傅里叶变换红外光谱表明，复合材料中壳聚糖的平均乙酰化度约为 82.5%。这表明壳聚糖在溶解过程中不会脱乙酰化为壳聚糖。X 射线衍射结果表明，复合材料的结晶度从无定形增加到 59%，随着壳聚糖浓度的增加，结晶度尺寸增加到 3nm。力学测试表明，当壳聚糖含量为 80wt%时，复合材料的最大拉伸应力为 4.7MPa，弹性模量为 27.4MPa，断裂伸长率为 78.7%。此外，水接触角测量表明，壳聚糖的存在使材料更具疏水性。
