การเตรียมแผ่นโปร่งแสงจากเซลลูโลสแอโรเจล

• Main Author: สาวิตรี สินธุ
• Other Authors: กาวี ศรีกูลกิจ
• Format: Theses and Dissertations
• Language: Thai
• Published: จุฬาลงกรณ์มหาวิทยาลัย 2017
• Subjects: เซลลูโลส; โซเดียมไฮดรอกไซด์; Cellulose; Sodium hydroxide
• Online Access: https://digiverse.chula.ac.th/Info/item/dc:34129
• Institution: Chulalongkorn University

In this work, translucent cellulose sheet was prepared from wet cellulose aerogel. The wet cellulose aerogel sheet was prepared via NaOH/urea dissolution system followed by multiple solvent exchanges. Firstly, water hyacinth cellulose solution was prepared and then cast into plastic mold. The casting solution was left standing to become solid hydrogel. Then, multiple solvent exchanges by water was carried out in order to remove NaOH and urea completely to obtain wet cellulose aerogel. Then, translucent cellulose sheet was successfully prepared by backfilling the nano/micro sized aerogel channel with a refractive index matching polymer. In this research, two types of polymethylmethacrylate emulsions (low Tg and high Tg) were employed. In all cases, translucent cellulose sheets exhibited 80-90 percent transparency. In contrast, cellulose aerogel exhibited relatively low percent transmittance only 8.24%. Then, the thermal conductivity was determined. In addition, the coefficient of thermal expansion (CTE) of the translucent sheet prepared from high Tg acrylic resin possessed a lower coefficient of thermal expansion than that prepared from low Tg commercial resin, indicating that high Tg acrylic resin was able to resist shape change. As a result, translucent cellulose sheet prepared from high Tg acrylic resin exhibited higher thermal resistancy than that prepared from low Tg acrylic resin.