Abstract

LOPEZ, Ángel; RIVAS, Johan; LOAIZA, Mariielys  and  SABINO, Marcos. DEGRADATION OF PLASTICIZER CHITOSAN FILM OBTAINED FROM SHRIMP SHELLS (L. vannamei). Rev. Fac. Ing. UCV [online]. 2010, vol.25, n.2, pp.133-143. ISSN 0798-4065.

This research attempts to develop a proposal for the development of biodegradable polymer film based on Chitosan, synthesized from chitin extracted from shells of shrimp species L. vannamei that can be found on the Peninsula of Paraguaná- Venezuela. Chitin was isolated from the shrimp shells selected through various chemical methods giving yields between 79 % and 94 %. Then, through thermal alkaline desacetilation, at 120 °C, chitosan was obtained, reaching levels of between 94 % and 97 %, and viscosimetric molecular weights between 3 x 10⁵ y 4 x 10⁵ g/mol. With the obtained chitosan, solutions were prepared using the solvent casting technique (at a temperature around 50 ºC) to prepare pure chitosan film and plastifiant chitosan adding 0.2 % of glycerin using dilute acetic acid as solvent. The mechanical properties of samples were determined, finding a good plasticizer effect through the presence of the glycerin. The study of degradation of the plastic film and the pure chitosan film was carried out in compost systems in different parts of the country (arid zone in Punto Fijo city and a wet zone in the city of Los Teques ). The degradation was measured by weight loss (%) and the superficial morphology of the films using scanning electron microscopy (SEM). The degraded films in the arid zone showed a decrease in the degradation rate compared to the degraded films in wetlands, as expected, due to the conditions given to the process of enzymatic hydrolysis that can occur in wetlands

Keywords : Shrimp (L. vannamei); Chitin; Chitosan; Biodegradable films; Plasticization; Compost systems.