近紫外光改質技術應用於透明竹材之研發

Abstract

本研究提出一種用於製備透明竹材的新型紫外光改質技術，以解決過往製作透明竹材時，藥劑滲透困難與結構破壞之問題，同時在減少化學藥劑使用的條件下，探討不同製程參數對材料之微觀結構、化學組成、光學、熱學及機械性質之影響。本研究以臺灣原生孟宗竹（Phyllostachys pubescens）為原料，利用不同時間條件下的熱鹼處理與甲苯處理結合紫外光改質選擇性去除木質素的發色基團，最後進行環氧樹脂灌注。其中以熱鹼處理與甲苯處理為雙因子進行試驗，結果證實熱鹼處理時間是影響透明竹材最終性質的關鍵因子。研究發現，經過2 h至4 h的熱鹼處理時間搭配無甲苯處理的組別展現了最佳的綜合性能。在光學性質方面，經熱鹼處理2 h與4 h之組別（TBN2、TBN4）在550 nm波長下之全光透射率皆超過93%，霧度控制在約65%，並具備優異的紫外光阻隔能力。在機械性質方面，雖然未經熱鹼處理的組別擁有較高的最大拉伸強度，但因其不具備透明性而不符使用需求；相對地，TBN2組別不僅能實現高透明度，且能在維持竹材本身拉伸強度的同時展現出優於玻璃的韌性與延展性。此外，經熱鹼處理4 h之組別（TBN4）雖強度稍降，但有更高的剛性，且其熱傳導係數低至0.24 W·m⁻¹·K⁻¹，僅為普通玻璃的四分之一，展現優異的隔熱潛力。綜上所述，本研究成功製備出兼具高透光、優良機械強度與隔熱性能的透明竹材，開創一種製備透明竹材的創新製程，並證實透過製程參數的優化可在維持優異光學性能的前提下保持透明竹材的機械性能，為次世代節能智慧建材提供了具潛力的生物複合材料解決方案。

This study reported a novel UV modification technique for fabricating transparent bamboo that addresses key challenges in conventional processing, including poor chemical penetration and structural degradation. With minimizing chemical usage, this approach systematically investigated how processing parameters influence the microstructure, chemical composition, and optical, mechanical properties and thermal conductivity of the resulting material. Using Taiwanese native Moso bamboo (Phyllostachys pubescens), the fabrication process consisted of hot alkali pretreatment, UV modification to selectively remove lignin chromophores, toluene treatment, and epoxy resin impregnation. A two-factor experimental design revealed that hot alkali treatment duration emerged as the critical determinant of final material properties. Samples treated with 2-4 hours hot alkali combined with no toluene treatment demonstrated optimal comprehensive performance. The TBN2 and TBN4 groups achieved over 93% transmittance at 550 nm with haze at approximately 65%, while providing excellent UV-shielding capabilities. Mechanically, TBN2 maintained tensile strength comparable to original bamboo while achieving high transparency and demonstrating superior toughness and ductility compared to glass. The TBN4 group exhibited enhanced rigidity with thermal conductivity as low as 0.24 W·m⁻¹·K⁻¹, one-quarter that of conventional glass, indicating excellent thermal insulation potential. This work demonstrates an innovative processing method that preserves mechanical performance while maintaining superior optical properties, offering a promising biocomposite solution for next-generation energy-efficient smart building materials.