Fabrication and characterisation of α-chitin nanofibers and highly transparent chitin films by pulsed ultrasonication.
α-Chitin nanofibers were fabricated with dried shrimp shells via a simple high-intensity ultrasonic treatment under neutral conditions (60 KHz, 300 W, pH=7). The diameter of the obtained chitin nanofibers could be controlled within 20-200 nm by simply adjusting the ultrasonication time. The pulsed ultrasound disassembled natural chitin into high-aspect-ratio nanofibers with a uniform width (19.4 nm after 30 min sonication). The EDS, FTIR, and XRD characterisation results verified that α-chitin crystalline structure and molecular structure were maintained after the chemical purification and ultrasonic treatments. Interestingly, ultrasonication can slightly increase the degree of crystallinity of chitin (from 60.1 to 65.8). Furthermore, highly transparent chitin films (the transmittance was 90.2% at a 600 nm) and flexible ultralight chitin foams were prepared from chitin nanofiber hydrogels.
Material Science and Engineering College, Key Laboratory of Bio-based Material Science and Technology, Ministry of Education, Northeast Forestry University, Harbin 150040, PR China.
Yun
Y
Lu
Qingfeng
Q
Sun
Xilin
X
She
Yanzhi
Y
Xia
Yixing
Y
Liu
Jian
J
Li
Dongjiang
D
Yang
D060105:Animal Shells / Q000737:chemistry*; D000818:Animals; D002686:Chitin / Q000737:chemistry*; D003460:Crystallization; D020100:Hydrogels; D006863:Hydrogen-Ion Concentration; D008855:Microscopy, Electron, Scanning; D057139:Nanofibers / Q000737:chemistry* / Q000648:ultrastructure; D033561:Penaeidae / Q000737:chemistry; D013010:Sonication; D017550:Spectroscopy, Fourier Transform Infrared; D014866:Waste Products
D020100:Hydrogels; D014866:Waste Products; D002686:Chitin
Chitin nanofiber; Film; Foam; Transparent; Ultrasonic