RESUMO
Chitosan nanofibers were easily prepared from dry chitosan powder using the Star Burst system, which employs a high-pressure water jet system. Although the chitosan nanofibers became thinner as the number of Star Burst passes increased, the fiber thickness did not change significantly above 10 passes. Crystallinity and the chitosan nanofiber length decreased after extensive treatment due to the strong collision forces breaking the fibers. The mechanical properties and thermal expansion of the chitosan nanofiber sheets were improved by increasing the number of passes up to 10, but further treatment resulted in a deterioration of these properties.
Assuntos
Quitosana/química , Dessecação , Nanofibras/química , Nanotecnologia/métodos , Animais , Cristalização , Módulo de Elasticidade , Luz , Nanofibras/ultraestrutura , Pós , Pressão , Suspensões , Temperatura , Resistência à Tração , Viscosidade , ÁguaRESUMO
Co-production of fermentable sugars and nanofibrillated cellulose from cassava pulp was achieved by the combination of thermophilic enzymes (endoglucanase, ß-glucosidase, and α-amylase) and a new atomization system (Star Burst System; SBS), which employs opposing water jets. The SBS represents a key technology for providing cellulose nanofibers and improving the enzymatic saccharification of cassava pulp. Depending on the enzymes used, the production of glucose from cassava pulp treated with the SBS was 1.2- to 2.5-fold higher than that from pulp not treated with the SBS. Nanofibrillated cellulose with the gel-like property in suspension was produced (yield was over 90%) by α-amylase treatment, which completely released trapped starch granules from the fibrous cell wall structure of cassava pulp pretreated with the SBS. The SBS provides an environmentally low-impact pretreatment system for processing biomass material into value-added products.