Synthesis and Characterization of Chitosan-PVA hydrogels for pesticide release
- PDF / 593,916 Bytes
- 11 Pages / 432 x 648 pts Page_size
- 22 Downloads / 214 Views
MRS Advances © 2020 Materials Research Society DOI: 10.1557/adv.2020.21
Synthesis and Characterization of Chitosan-PVA hydrogels for pesticide release Rafael Nuñez-Reyes1, José Luis García-Rivas1*, Beatriz Garcia-Gaitan1 Beatriz Magdalena Millan-Olvera1 y Marithza Guadalupe Ramírez-Gerardo2
1 Tecnológico Nacional de México/IT de Toluca. Av. Tecnológico s/n. Colonia Agricola Bellavista Metepec, Edo. De México C.P. 52149. 2 Tecnológico de estudios superiors de Villa Guerrero; Carretera Federal Toluca-Ixtapan de la Sal Km 64.5, La Finca, Villa Guerrero.
*[email protected]
ABSTRACT Chitosan (Ch)-Polyvinyl (alcohol) (PVA) hydrogels cross-linked with sodium tripolyphosphate were synthetized to obtain a polymer matrix encapsulating an insecticide (active ingredient: imidacloprid). Imidacloprid release tests were performed separately with moist and lyophilized hydrogel beads with a diameter of 3.47 and 3.30 mm respectively. The concentration of the insecticide released in the medium was determined by UV-Visible spectroscopy, reaching equilibrium for wet hydrogels at 72h at a concentration of 330 mg L-1 and 281 mg L-1 in 48h for lyophilized hydrogels, comparing it with a maximum load of 330.18 mg L-1of imidacloprid contained in the hydrogels. The characterization of hydrogels was performed by Fourier transform infrarred spectroscopy (FTIR) to determine the functional groups. The morphology of the polymer matrix of the hydrogels was carried out in a scanning electron microscope (SEM). The size distribution and diameter of bead samples were observed through a stereomicroscope. The percentage of humidity of the hydrogels was determined obtaining 94.8% once the imidacloprid was released. the pore size of the samples was determined by the Brunauer-Emmet-Teller (BET) technique. The techniques used indicated that controlled release of imidacloprid could be more efficient with wet hydrogels in relation to the maximum load of imidacloprid contained, for protection of crops is necessary for a long time because of insecticide disponible in the soil.
INTRODUCTION: Agricultural production has a negative effect on sewage from nitrates, phosphates and pesticides. Pesticide use is the activity most frequently for the control of 3269
Downloaded from https://www.cambridge.org/core. Rice University, on 23 Mar 2020 at 08:19:41, subject to the Cambridge Core terms of use, available at https://www.cambridge.org/core/terms. https://doi.org/10.1557/adv.2020.21
organisms, however, due to its toxic properties, the use of pesticides is in many cases a risky and inappropriate practice, especially for farmers [1]. For greater control in the use of pesticides, encapsulate them in hydrogels have been an alternative which they are based on a three-dimensional network of polymers that have trapped active ingredients and could release during several days in the farmlands for protecting the plants, avoiding by this way the excessive concentrations applied by sprinkling and therefore environmental pollution. For this reason, natural bio
Data Loading...
