木質板材膨脹型塗料配方效應與反應機制

Studies of the Intumescent Formulations onto the Wood Panels' Coatings: their Effects and Reaction Mechanisms

莊智勝(Chih-Shen Chuang)

指導教授 ： 柯淳涵 ； 王明光

國立臺灣大學/生物資源暨農學院/森林環境暨資源學研究所/博士(2010年)

https://doi.org/10.6342/NTU.2010.02630

摘要

木材和木質材料在居住和建築上佔有很重要的地位，尤其是在室內裝修材料的使用上。而最常使用在室內裝修的水性樹脂，為壓克力系樹脂和醋酸乙烯系樹脂兩種。壓克力系樹脂包含壓克力乳化樹脂、苯乙烯壓克力共聚合乳化樹脂和醋酸乙烯壓克力共聚合乳化樹脂，而醋酸乙烯系樹脂則包含乙烯醋酸乙烯樹脂和具醋酸乙烯樹脂。本研究之目的，為解膨脹型塗料在不同配方下，各原料間的交互作用。包含(1)水性塗料，利用兩大木材常用之水性樹脂(亦即壓克力系統和醋酸乙烯系統)作為載體樹脂，(2)異戊四醇作為碳源劑，(3)三聚氰胺為發泡劑，(4)聚磷酸銨為脫水劑，探討在不同比例含量的配方下，阻燃效果較佳的混合比例。本研究主要探討載體樹脂和碳源劑的比例，對膨脹型塗料之影響，同時測試發泡劑和脫水劑的比例在阻燃性能上之相互關係，並以圓錐量熱儀做為阻燃性能測試儀器。本研究結果發現，塗佈膨脹型防火塗料確有提升合板阻燃性能的效用。其主要保護木材的能力，是由於酸和醇的反應產生酯化炭層阻擋熱傳遞。酯化炭層的形成時間，對於阻燃效果有極大之影響。較低含量的載體樹脂，可以有效提升膨脹型防火塗料之阻燃性能。不論是壓克力系列的樹脂，或是醋酸乙烯系列之樹脂，皆是以較低含量之載體樹脂，具有較佳之阻燃性能。同時，發泡劑含量過多時，亦會阻礙磷酸酯炭層之形成。本研究並利用FT-IR和NMR對於塗膜層進行燃燒機制之分析，由FT-IR分析可知，膨脹型炭層受熱裂解時，主要的結構會逐漸消失，而在載體樹脂含量較低時，磷酸酯炭層具有較佳的耐久性。另外，本研究利用市售有機黏土礦物提升塗料的阻燃性能，結果顯示添加有機黏土礦物後，能有效提昇膨脹型塗料的阻燃性能，且經由不同種類(亦即 30B, 10A and 15A)和不同添加量(亦即1, 3, 5 與10 %)得知，添加黏土礦物後，可以降低峰值熱釋放率和延長合板燃燒的時間。以30B添加3%和10A添加5%具有最佳的阻燃性能。由FT-IR和27Al、31P NMR分析結果，亦可以發現添加有機黏土礦物可以提升膨脹型炭層的耐久度，並形成磷酸鋁之結構。此外，磷酸酯炭層和磷酸鋁可以形成兩道阻擋層，提升膨脹型塗料保護合板的阻燃效果。本研究之結果，可於未來協助設計更佳之木材用膨脹型防火塗料。

關鍵字

膨脹型塗料 ； 圓錐量熱儀 ； 有機黏土 ； 31P NMR ； 磷酸酯炭層 ； 聚磷酸銨

並列摘要

Wood and wood-based materials are of great importance in residential and building construction, especially for indoor furnishings. Acrylic and vinyl acetate emulsion resin are the two most common emulsion resins employed for indoor furnishings. Acrylic resin includes three different emulsion resins: acrylic, styrene acrylic copolymer, and vinyl acetate acrylic copolymer emulsion resins. Vinyl acetate emulsion resin includes two different resins: ethylene vinyl acetate copolymer and polyvinyl vinyl acetate emulsion resin. This study investigated the enhancement of the fire retardance of coated plywood by interaction among four major components of intumescent formulation: (1) acrylic emulsion resin and vinyl acetate emulsion resin as binder resin (BR), (2) pentaerythritol as carbonizing substance (CS), (3) melamine as foam producing substance (FPS) and (4) ammonium polyphosphate as dehydrating agent (DA). Effects of changing BR/CS ratios and FPS/DA ratios on flame-retardance of coated plywood were investigated using a cone calorimeter. The intumescent formulation significantly enhanced fire retardancy of coated plywood by exhibiting lower peak release rates and longer times to peak release rates, compared with uncoated plywood (UP) panel and plywood panel solely coated with emulsion resin. Lower BR contents resulted superior thermal properties and demonstrated improved flame retardancy. The weight losses for the coating films, identified by thermogravimetrical analysis, were consistent with the improved flame retardancy for coated plywood. Infrared analysis of the chars indicated that the formation of phosphate ester linkages with the decreased BR and FPS contents had led the enhancements of flame retardancy for coated red lauan plywood. On the other hand, acrylic emulsion resin, combined with organo-clay, also demonstated a good thermal property. The intumescent formulations, added with different types of Cloisite clays (i.e., 30B, 10A and 15A) and different amounts (1, 3, 5 and 10 %), significantly enhanced the fire retardancy of coated plywood by exhibiting lower peak heat release rates (PHRR) and extending the time to reach PHRR. The importance of the amount of organo-clays addition was shown by this study. In addition, the addition of 3 % Cloisite 30B and 5 % Cloisite 10A had result the optimal flame retardancy. The FT-IR, 27Al and 31P NMR analyses demonstrated that the organo-clay addition extended the durability of the intumescent phosphor-carbonaceous char structure and formed aluminophosphate structures. In addition, a dual blocking layer could be formed by the phosphor-carbonaceous char structure and aluminophosphate structures. The findings in this study could assist designing better intumescent coatings for wood panels in the future.

並列關鍵字

Intumescent coating ； Cone calorimeter ； Organo-clay ； 31P NMR ； Phosphor-carbonaceous char ； Ammonium polyphosphate

參考文獻

莊智勝 2004 不同載體樹脂及其配方對膨脹型防火塗料之特性效應。國立台灣大學森林學研究所碩士論文。pp 22。

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