Síntese e caracterização de hidrogéis de poliacrilamida e metilcelulose para liberação controlada de pesticidas

Detalhes bibliográficos
Ano de defesa: 2009
Autor(a) principal: Aouada, Fauze Ahmad
Orientador(a): Mattoso, Luiz Henrique Capparelli lattes
Banca de defesa: Não Informado pela instituição
Tipo de documento: Tese
Tipo de acesso: Acesso aberto
Idioma: por
Instituição de defesa: Universidade Federal de São Carlos
Programa de Pós-Graduação: Programa de Pós-Graduação em Química - PPGQ
Departamento: Não Informado pela instituição
País: BR
Palavras-chave em Português:
Área do conhecimento CNPq:
Link de acesso: https://repositorio.ufscar.br/handle/20.500.14289/6109
Resumo: In this thesis, the preparation and characterization of hydrogels of methylcellulose (MC) mechanically supported in polyacrylamide (PAAm) network for controlled release of pesticide were reported. The controlled release of pesticide paraquat was investigated using UV-Visible spectroscopic technique. The results showed that the presence of MC increased the flexibility of the matrixes. By varying of acrylamide (AAm), cross-linker and MC concentrations, it was possible to obtain hydrogels with mechanical and hydrophilic properties controlled and optimized for some specific application. The swelling degree values varied from 10 to 210 g/g. The mechanical properties values (maximum compressive stress and modulus of elasticity) varied from 0.55 to 22.33 kPa and from 1.06 to 27.50 kPa, respectively. The kinetic and structural properties were strongly influenced by the AAm, MC, pH and ionic strength of swelling medium. The kinetic release control of pesticide (until 30 days) could be adjusted by controlling the wateruptake of the hydrogels through the AAm/MC ratio. Hydrogels based on PAAm and MC polymers could be considered as promising materials for application in agriculture, in special, controlled release of agrochemicals.