| Autor: |
Lee, DW, Lim, C, Israelachvili, JN, Hwang, DS |
| Jazyk: |
angličtina |
| Rok vydání: |
2013 |
| Zdroj: |
Lee, DW; Lim, C; Israelachvili, JN; & Hwang, DS. (2013). Strong adhesion and cohesion of chitosan in aqueous solutions. Langmuir, 29(46), 14222-14229. doi: 10.1021/la403124u. UC Santa Barbara: Retrieved from: http://www.escholarship.org/uc/item/2z61027p |
| DOI: |
10.1021/la403124u. |
| Popis: |
Chitosan, a load-bearing biomacromolecule found in the exoskeletons of crustaceans and insects, is a promising biopolymer for the replacement of synthetic plastic compounds. Here, surface interactions mediated by chitosan in aqueous solutions, including the effects of pH and contact time, were investigated using a surface forces apparatus (SFA). Chitosan films showed an adhesion to mica for all tested pH ranges (3.0-8.5), achieving a maximum value at pH 3.0 after a contact time of 1 h (Wad∼ 6.4 mJ/m2). We also found weak or no cohesion between two opposing chitosan layers on mica in aqueous buffer until the critical contact time for maximum adhesion (chitosan-mica) was reached. Strong cohesion (Wco∼ 8.5 mJ/m2) between the films was measured with increasing contact times up to 1 h at pH 3.0, which is equivalent to ∼60% of the strongest, previously reported, mussel underwater adhesion. Such time-dependent adhesion properties are most likely related to molecular or molecular group reorientations and interdigitations. At high pH (8.5), the solubility of chitosan changes drastically, causing the chitosan-chitosan (cohesion) interaction to be repulsive at all separation distances and contact times. The strong contact time and pH-dependent chitosan-chitosan cohesion and adhesion properties provide new insight into the development of chitosan-based load-bearing materials. © 2013 American Chemical Society. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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