This study investigated the characteristics of radial cracks in Castanopsis hystrix wood and evaluated its dimensional stability after impregnation with low-molecular-weight polyacrylate (PA), melamine-urea-glyoxal (MUG), and melamine-urea-formaldehyde (MUF) resins. The physical properties were examined by dimensional stability measurements, dynamic vapor sorption (DVS) analysis, and scanning electron microscopy (SEM). The results showed that radial cracks were easily produced in the transverse section of untreated wood during drying. The surfaces of the radial cracks exhibited an even and clean structure without fluffs on the pair of surfaces, and cracks spanned 4–5 annual rings. The resin-impregnated wood showed no radial cracks on its transverse surface. C. hystrix wood modified with MUG and MUF exhibited a higher weight percentage gain (WPG) than wood modified with the same concentration of PA resin. The resin-impregnated C. hystrix wood also showed reduced anisotropy and improved dimensional stability. The SEM images of the modified wood showed that the wood pits and cells were filled with resin, while the cell wall surfaces were covered with a layer of resin.

中文翻译：

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槠木材的径向裂纹及其树脂浸渍改性改善尺寸稳定性

本研究主要研究了径向裂纹的特征。槠木材并评估其用低分子量聚丙烯酸酯（PA）、三聚氰胺-脲-乙二醛（MUG）和三聚氰胺-脲-甲醛（MUF）树脂浸渍后的尺寸稳定性。通过尺寸稳定性测量、动态蒸气吸附（DVS）分析和扫描电子显微镜（SEM）检查物理性能。结果表明，未经处理的木材在干燥过程中横截面容易产生放射状裂纹。径向裂纹表面结构均匀、干净，无绒毛，裂纹跨越4~5个年轮。树脂浸渍木材在其横向表面上没有显示出径向裂纹。C. hystrix用MUG和MUF改性的木材比用相同浓度的PA树脂改性的木材表现出更高的重量百分比增益（WPG）。树脂浸渍的C. hystrix木材还表现出降低的各向异性和提高的尺寸稳定性。改性木材的SEM图像显示，木材的凹坑和细胞充满了树脂，而细胞壁表面覆盖有一层树脂。