Modified avocado seed starch and pineapple crown cellulose for the production of biofilms: Resistance to tension, deformation and rigidity

Resumen

In this research, starch was extracted from avocado seeds (Persea Americana Mill) and cellulose from pineapple crowns (Ananas comosus) to produce biofilms. The research focused on studying the effect of the percentage of microcellulose and plasticizer on the tensile strength, deformation and rigidity of biofilms based on modified starch reinforced with cellulose microfibers (45, 50 and 55%;). Starch and cellulose were extracted by wet extraction and treatments (alkaline and acid), respectively. The shaping method used for the biofilms was solution fusion and glycerin was used as a plasticizer at doses of 20, 25 and 30%. The results showed maximum tensile strength and stiffness values of 12.1 MPa and 54.1 MPa respectively; in films reinforced with 55% cellulose and plasticized with 20% glycerin, although the maximum percentage deformation (42.6%) was reached in biofilms with 50% cellulose and 25% glycerin. Meanwhile, the lowest tensile strength values (7.2 MPa) were achieved with 45% cellulose and 30% glycerin, while the lowest stiffness (18.6 MPa) was achieved with 50% cellulose and 25 % glycerin, and the minimum deformation was 22% with 45% cellulose and 20% glycerin. It was concluded that as the weight percentage of cellulose increases up to 55% in the biofilms, the average values of tensile strength and stiffness increase, On the contrary, as the weight percentage of glycerin increases up to 25%, the tensile strength and rigidity decrease; Regarding the percentage deformation of the biofilms, they presented an inverse effect. This study aimed to expand research on biofilms used as biodegradable packaging.