頁籤選單縮合
題 名 | 光安定劑改善聚胺基甲酸酯透明塗裝木材耐光性之解析=Illustration of the Effect of UV-stabilizers on the Photostability Improvement of Wood Coated with Clear Polyurethanes |
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作 者 | 張上鎮; 葉汀峰; | 書刊名 | 中華林學季刊 |
卷 期 | 30:4=119 1997.12[民86.12] |
頁 次 | 頁451-460 |
分類號 | 474.33 |
關鍵詞 | 聚胺基甲酸酯透明塗料; 游離塗膜; 光安定劑; 光劣化; 變色; 化學結構變化; 傅立葉紅外線光譜分析; Polyurethane clear coating; Free film; UV-stabilizer; Photodegradation; Discoloration; Chemical structure changes; Fourier transform infrared spectroscopy; |
語 文 | 中文(Chinese) |
中文摘要 | 由於光安定劑可以改善聚胺基甲酸酯透明塗裝木材之耐光性,為瞭解其對塗膜與 木材本身光安定性改善之程度,本試驗以含光安定劑之聚胺基甲酸酯游離塗膜覆蓋於木片 上,模擬含光安定劑聚胺基甲酸酯塗裝之木材。試材經人工加速耐光試驗後,分別以紫外光- 可見光光譜儀配合積分球及傅立葉紅外線光譜儀評估塗膜與木片本身的變色及化學結構變 化。試驗結果顯示,含光安定劑之芳香族聚胺基甲酸酯(PU)塗裝的木材,試材的變色於照光 初期係由塗膜及木材兩者的變色所共同造成,但隨著照光時間的增加,其顏色變化則主要是 由塗膜變色所造成。僅含2% Tinuvin-1130光安定劑PU塗裝者及含2% Tinuvin-1130與1% Tinuvin-123兩種光安定劑PU塗裝者,因紫外光無法穿透塗膜,底層木材劣化程度較小,而 達到減緩木材劣化之目的。含1% Tinuvin-123光安定劑之PU塗裝材,由於塗膜會穿透大量 紫外光至底層木材,不但塗膜變色,底層木材亦嚴重變色,經化學結構分析得知,塗膜的胺 基甲酸酯鍵及木材表面木質素成份均受破壞。至於含有2% Tinuvin-1130光安定劑脂肪族聚 胺基甲酸酯(PUA)塗裝之木材,由於塗膜具有極佳的光安定性,在照光過程中幾乎不變色,但 部份可穿透塗膜的紫外光及較多的可見光仍使其底下木材產生變色,顯然的,PUA塗裝材之 光變色係由膜下之木材受光影響產生顏色變化所造成;另經由紅外線光譜分析得知,含光安定 劑之PUA塗膜下木材之化學結構因受光影響產生的變化較不含光安定劑PUA塗膜下的木材輕 微,由此顯示,含有2% Tinuvin-1130光安定劑脂肪族聚胺基甲酸酯塗膜亦可減緩木材之光 劣化。 |
英文摘要 | This study was to understand the photostability of film itself and wood underneath during the photodegradation of woods coated with clear polyurethane (PU) containing UV-stabilizers. Wood sections covered with free films of PU containing UV-stabilizers were used to simulate actual coated wood conditions. After exposure to accelerated lightfastness test, the changes in color and chemical structure of the specimens were examined by UV-visible spectrometer equipped with integrating sphere apparatus and Fourier transform infrared spectroscope (FTIR), respectively. Results showed that the discoloration of wood coated with aromatic PU containing UV-stabilizers was caused by both film itself and wood underneath during the early period of photodegradation, but as time continued, the discoloration of coated wood was induced mainly by the film itself. Neither PU film containing 2% Tinuvin-1130 nor PU film containing both 2% Tinuvin-1130 and 1% Tinuvin-123 could transmit UV light * hence preventing the degradation of wood underneath. For woods coated with PU containing 1% Tinuvin-123 due to highly transmission of UV light through film, therefore, not only the film itself but also the wood underneath were discolored. The chemical structure analyses showed that the urethane linkage of PU film containing Tinuvin-123 was changed, and the lignin constituent of wood underneath was also degraded. Because of excellent light stability of aliphatic PU film (PUA) containing 2% Tinuvin-1130, discoloration was not appeared during photoirradiation, while the color of wood beneath PUA film containing 2% Tinuvin-1130 was changed due to the penetration of some UV light and more visible light through the film. We concluded that the discoloration of wood coated with PUA containing Tinuvin-1130 was induced mainly by the color changes of wood underneath. However, the changes of the chemical components of wood beneath PUA film containing Tinuvin-1130 were much less than those of wood beneath PUA film after irradiation, revealing that photodegradation of wood underneath the PUA film containing Tinuvin-1130 was partially retarded. |
本系統中英文摘要資訊取自各篇刊載內容。