Faculty of Chemistry and Materials Sciences, Department of Biotechnology and Chemical Technology, Aalto University School of Science and Technology, P.O. Box 11000, 00076 Aalto, Finland.
Biomacromolecules. 2010 Dec 13;11(12):3511-8. doi: 10.1021/bm101007u. Epub 2010 Oct 25.
The insertion of oat husk lignin onto chemithermomechanical pulp (CTMP) fibers was studied to increase fiber hydrophobicity. The pretreated pulp samples were subsequently used for preparation of handsheets for characterization. Treatment of CTMP with laccase in the presence of oat husk lignin resulted in a significant increase in hydrophobicity of the handsheet surface, as indicated by dynamic contact angle analysis. Water absorption time of 8 s was obtained with initial contact angle of 118°. Although the handsheet's brightness was reduced by 33%, tensile index was only subtly decreased. Neither laccase nor oat husk lignin alone gave much improved water absorption times. Therefore, handsheets made of laccase-treated pulp with and without oat husk lignin were further examined by XPS, which suggested that both laccase and oat husk lignin were inserted onto CTMP fibers. The oat husk lignin was distributed as heterogeneous aggregates on the handsheet surface whereas laccase was uniformly distributed. Evidence was obtained that the adsorbed laccase layer formed a noncovalent base for the insertion of oat husk lignin onto fiber surfaces.
研究了将燕麦壳木质素插入化学机械浆（CTMP）纤维中，以增加纤维的疏水性。预处理后的纸浆样品随后用于制备手抄片进行特性表征。在存在燕麦壳木质素的情况下，用漆酶处理 CTMP 导致手抄片表面疏水性显著增加，这可以通过动态接触角分析来表明。初始接触角为 118°时，吸水率为 8 秒。尽管手抄片的白度降低了 33%，但其拉伸指数仅略有下降。单独使用漆酶或燕麦壳木质素都不能显著提高吸水率。因此，进一步通过 XPS 检查了用漆酶处理的含有和不含有燕麦壳木质素的纸浆制成的手抄片，结果表明漆酶和燕麦壳木质素都被插入到 CTMP 纤维中。燕麦壳木质素在手抄片表面呈不均匀的聚集态分布，而漆酶则均匀分布。有证据表明，吸附的漆酶层为燕麦壳木质素插入纤维表面提供了非共价基础。
