自製功能性二氧化鈦複合加固劑，於文化資產保存抗汙行為評估

The Evaluation of Antifouling for Composite Consolidants with Nano TiO_2 and Commercial Stone Consolidants Treated on Cultural Artifacts

本研究成功利用水熱法合成奈米二氧化鈦粉末，相較於商用奈米二氧化鈦粉末，其分解亞甲基藍溶液（有機汙染物）半衰期（一半初始濃度）需4小時，然而本案自製之奈米二氧化鈦僅需3.5小時。此外，本研究也成功開發複合功能性加固劑，自製加固劑添加矽氧烷聚合物可有效地抑制塗層體積的收縮，因而減低塗層因收縮而破裂的發生。由於矽氧烷聚合物為長鏈型聚合物且兩端帶有氫氧官能基，氫氧官能基可與矽氧烷膠體反應並鏈結產生韌性，並且降低因不均勻快速水解縮合反應產生之破裂現象。在抗汙方面，其在紫外光照射下可於5小時降解亞甲基藍使石材表面恢復到原有色彩，而沒有添加奈米二氧化鈦之加固劑在紫外光照射下仍無法恢復原有色彩。在耐候測試上，商用加固劑經20個循環後，其表面已不具有疏水效果，而新型功能型加固劑其表面雖有被破壞但仍保有部分疏水效果。另於生物防治方面，本研究發現奈米二氧化鈦於低孔隙率花崗岩表面是有生物防治之效果，施作手法則較無明顯差異性，二氧化鈦之含量是影響生物防治的關鍵，以0.5 wt% TiO_2效果較佳，光催化效應得以分解有機物，達生物防治及自潔之效果。

This study successfully synthesized TiO_2 nanoparticles powder by hydrothermal method. As a result, hydrothermally synthesized TiO_2 decompose methylene blue solution(organic pollutants) in 3.5 hours while commercial TiO_2 takes 4 hours. This research was also successfully developed a new functional consolidate with TiO_2 nanoparticles. The addition of siloxane to the synthesized silicate consolidant could effectively reduce the occurrence of cracking because it belonged to a linear polymer which had elasticity property, therefore, xerogel from synthesized silicate consolidant had toughness property. In the Antifouling testing, composite consolidants with TiO_2 decomposed methylene blue solution(organic pollutants) on the surface of stone in 5 hours while commercial consolidants without TiO_2 can not decompose the pollutants. In the weathering test, the surface of commercial has no hydrophobic effect after 20 cycles, while the surface of the new functional consolidate still retains a part of the hydrophobic effect. For the biofouling prevention, the TiO_2 ratio of consolidates was important. For more TiO_2 in consolidate, the biofouling prevention was more effective. In the results,0.5 wt% TiO_2 was the better ratio to apply on low porosity stone such as marble for biofouling prevention.