人造板吸水过程的 TD-NMR 动态研究

利用时域核磁共振(TD-NMR)技术，为研究人造板和水分的关系提供新方法．该文通过研究胶合板(Plywood)、刨花板(Particle board)、中密度纤维板(Medium Density Fiberboard) 3 种常用人造板吸水过程中水分的自由感应衰减(FID)信号的变化，得出传统称重法得到的吸水率与吸水过程中测得的 FID 信号高度线性相关， 24 h 吸水率由大到小依次为胶合板>刨花板>中密度纤维板．通过 3 种人造板 24 h 吸水过程中自旋-自旋弛豫时间(T₂)大小及分布的实验数据，分析了吸水过程中人造板中水分的状态．实验结果证实了TD-NMR 是研究人造板与水分的关系的一个有效手段．

Water Absorption in Wood-Based Panel Observed by Dynamic Time-Domain Nuclear Magnetic Resonance Spectroscopy

Time-domain nuclear magnetic resonance (TD-NMR) technology may provide a new method to study water absorption in wood-based panels. We measured changes of free induction decay (FID) signal of water in plywood, particle board and medium density fiberboard after a 24-hour soaking process, and the results were correlated to water contents calculated with the traditional weighing method. The amount of water absorption was plywood > particleboard > medium density fiberboard. The state of water in the panels was analyzed by spin-spin relaxation time (T2) measurements. The result suggested that NMR is an effective tool to study the relationship between wood-based panels and water.