光劣化塗膜之紅外線光譜分析技術之比較

Comparison of IR Spectroscopic Techniques for the Analysis of Coating Film Degraded by UV-light

張上鎮(Shang-Tzen Chang) ； 顧文君(Wen-Jun Ku)

《林業試驗所研究報告季刊》 Volume 6 Issue 1 (1991/03) Pp. 45-56

https://doi.org/10.7075/BTFRI.199103.0045

Abstracts

塗料之功能爲保護與美化木質製品，但是卻很容易受光影響而產生化學變化，本試驗以三種紅外線光譜分析技術，即傳統穿透透明塗膜、穿透溴化鉀圓板、衰減全反射(MIR)，分析受光影響後之硝化棉與聚胺基甲酸酯塗料的化學變化。試驗分析結果得知，傳統以紅外光穿透透明塗膜與穿透溴化鉀圓板二種分析方法適用於分析經過長時間光劣化塗膜之化學變化，而衰減全反射則爲一靈敏之非破壞性分析技術，適用於偵測塗膜於光劣化初期時所產生輕微的表面化學變化，並可分析傳統穿透式分析技術所無法分析的不透明塗膜之化學結構變化。此外，三種紅外線光譜分析技術之優劣點及其特性亦於文中詳細討論與比較。

Keywords

塗膜光劣化 ； 硝化棉塗料 ； 聚胺基甲酸酯塗料 ； 紅外線光譜分析 ； 穿透式分析 ； 衰減全反射分析 ； 溴化鉀圓板 ； 化學變化

Parallel abstracts

Although clear coatings perform protection and decoration function, they are susceptible to photodegradation after exposure to ultraviolet light. In order to improve the photostablilty of clear coatings the light-induced degradation mechanisms should be elucidated. Infared spectroscopy lies played on important role in the analysis of protective coatings. Therefore, in this study three different infrared sample preparations including transmission film, KBr disc and multiple internal reflectance (MIR) were applied to monitor the variations of infrared spectra of nitrocellulose and polyurethane coatings degraded by ultraviolet light (λ＞275nm). Experimental results indicate that MIR is an excellent non-destructive surface analytical technique for early detection of subtle chemical changes occurring at tap surface of coatings after a short-teem exposure period. The others are insensitive for the detection of she early indications of coating deterioration, bat are useful for monitoring the surface changes in competition after exposure to ultraviolet light for longer periods. The nature of the infrared analytical data provided by these three different techniques is compared in details in the study.

Parallel keywords

Nitrocellulose ； polyurethane ； coating ； photodegradation ； infrared spectroscopy ； transmission spectrum ； MIR spectrum ； KBr disc ； chemical change