Chitin Nanofibers / Epoxy Resin Optically Transparent Nanocomposite Films

Abstract

Chitin nanofibers were prepared from prawn shell by a simple mechanical treatment after the removal of proteins and minerals. Since the exoskeleton of prawn is made up of a finer structure nano-fibrillation of prawn shell is easy, which allows chitin nanofibers to be prepared under neutral pH conditions. The obtained nanofibers were observed by FE-SEM and found to have a uniform width of approximately 20-40nm and high aspect ratio that more than 1000. Due to the size effect of the chitin nanofibers, the nanocomposite films had high transparency that the chitin nanofibers/epoxy resin nanocomposite transmitted 85.2% of light compared to the light transmittance of pure epoxy resin（91%）and the light transmittance of pure chitin nanofibers sheet (70.1%) at a visible wavelength of 600nm. In the study the coefficient of thermal expansion (CTE) from 20 to 160°C of the epoxy resin sheet was measured to be 170 ppm/K. By adding 40 wt% of chitin nanofibers, the CTE of the epoxy resin dropped to 22 ppm/K, approximately 1/8th of its original value. The novel material is a candidate for transparent substrates in the manufacturing optoelectronic devices such as flexible displays and solar cells.

Nanomaterials Derived from Fungal Sources—Is It the New Hype?

“…Research involving nanoscale chitin in a thermoset matrix is much rarer. The first study was published in 2013, when Shao et al 70…”

“…Research involving nanoscale chitin in a thermoset matrix is much rarer. The first study was published in 2013, when Shao et al impregnated 40% ChNFs with an epoxy resin. No data on mechanical properties were presented.…”