Portal de Periódicos da CAPES

Synthesis and characterization of chitosan alkyl carbamates

2002; Wiley; Volume: 86; Issue: 11 Linguagem: Inglês

10.1002/app.11252

1097-4628

Galo Cárdenas, Juan Carlos Paredes, Gustavo Cabrera‐Barjas, Pedro Casals,

Synthesis and properties of polymers

Abstract The synthesis of chitosan methylcarbamate (ChMC) and ethylcarbamate (ChEC) is described by using a new methodology. Polymers with substitution degrees up to 63% for ChEC and 68.5% for ChMC were obtained. Derivatives with lower substitutions were acid soluble but those with higher ones were completely insoluble. This could be due to the loss in hydrophilic sites when the substitution degree increases. The reaction conditions and degree of substitution obtained for both derivatives were also described. A complete chemical characterization was carried out by spectroscopic techniques. The thermal degradation of chitosan and derivatives were studied in the range 25–500°C and both derivatives were shown to be thermally less stable than chitosan. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2742–2747, 2002