Institute of Wood Technology and Renewable Materials, Department of Materials Sciences and Process Engineering, BOKU-University of Natural Resources and Life Sciences Vienna, Konrad-Lorenz-Straße 24, 3430 Tulln, Austria.
Department of Chemistry, Lehigh University, 6 East Packer Avenue, Bethlehem, Pennsylvania 18015, United States.
Biomacromolecules. 2020 Oct 12;21(10):4244-4252. doi: 10.1021/acs.biomac.0c01028. Epub 2020 Sep 11.
Peak force infrared (PFIR) microscopy is a recently developed approach to acquire multiple chemical and physical material properties simultaneously and with nanometer resolution: topographical features, infrared (IR)-sensitive maps, adhesion, stiffness, and locally resolved IR spectra. This multifunctional mapping is enabled by the ability of an atomic force microscope tip in the peak force tapping mode to detect photothermal expansion of the sample. We report the use of the PFIR to characterize the chemical modification of bio-based native and intact wooden matrices, which has evolved into an increasingly active research field. The distribution of functional groups of wood cellulose aggregates, either in native or carboxylated states, was detected with a remarkable spatial resolution of 16 nm. Furthermore, mechanical and chemical maps of the distinct cell wall layers were obtained on polymerized wooden matrices to localize the exact position of the modified regions. These findings shall support the development and understanding of functionalized wood materials.
峰值力红外（PFIR）显微镜是一种最近开发的方法，可以同时以纳米分辨率获得多种化学和物理材料特性：形貌特征、红外（IR）敏感图、附着力、硬度和局部分辨 IR 光谱。这种多功能映射是通过在峰值力探测模式下原子力显微镜尖端检测样品的光热膨胀的能力实现的。我们报告了使用 PFIR 来表征生物基天然和完整木质基质的化学修饰，这已经发展成为一个越来越活跃的研究领域。用 16nm 的显著空间分辨率检测了木纤维素聚集体的官能团分布，无论是在天然状态还是羧化状态。此外，在聚合木质基质上获得了不同细胞壁层的机械和化学图谱，以定位改性区域的确切位置。这些发现将支持功能化木材材料的开发和理解。
