Incorporação de partículas de hidrogel em microfibras de borracha natural obtidas por fiação por sopro em solução
Carregando...
Data
2021-07-28
Autores
Cerna Ñahuis, Liesel Eulalia
Título da Revista
ISSN da Revista
Título de Volume
Editor
Universidade Estadual Paulista (Unesp)
Resumo
Neste trabalho, microfibras de borracha natural (BN) e de compósitos a base de borracha natural com incorporação de diferentes quantidades de partículas de hidrogel (H) foram sintetizados usando a técnica de fiação por sopro em solução. Os hidrogéis utilizados foram constituídos de poliacrilamida (PAAm) e carboximetilcelulose (CMC). Fibras com estrutura morfológica em forma de fitas foram obtidas tanto para as microfibras de BN quanto para os compósitos BN/H com largura média entre 17-27 µm e 36-39 µm, respectivamente. As análises de FTIR indicaram não haver interações químicas entre os dois materiais. Os resultados das análises termogravimétricas TG e DTG dos compósitos apresentaram perda de massa no intervalo de 25-200°C e 200-290°C, associadas ao comportamento térmico individual do hidrogel. As curvas de DSC para os compósitos apresentaram dois eventos endotérmicos, um no intervalo de -164 a -163,5°C, atribuído à transição vítrea (Tg) da BN e o outro entre 109 a 117°C, associado a Tg do hidrogel superposto a processos irreversíveis influenciados pela presença de água no compósito. As curvas de tração das membranas microfibradas de BN e dos compósitos, apresentaram perfis semelhantes. Apresentaram também um incremento na tensão na ruptura em relação ao filme denso da BN. Este incremento foi atribuído principalmente ao alinhamento das microfibras durante o tensionamento. A tensão e deformação na ruptura dos compósitos diminuíram com o aumento de conteúdo de hidrogel nas fibras indicando fraca interação física entre a BN e o hidrogel. O grau de intumescimento das membranas compósitas fiadas mostrou ser dependente da quantidade de hidrogel incorporada nas fibras, atingindo um valor de aproximadamente 1427% para a membrana compósita obtida com a relação em massa de BN/H (1:2). A possibilidade de fabricar membranas com diferentes graus de intumescimento, maleáveis, abrem perspectivas promissoras para aplicações na área biomédica como materiais com liberação controlada de fármacos.
In this work, natural rubber microfibers (BN) and natural rubber-based composites incorporated with different amounts of hydrogel particles (H) were produced by solution blow spinning technique. The hydrogels used consisted of polyacrylamide (PAAm) and carboxymethylcellulose (CMC). Fibers with morphological structure in the form of ribbons were obtained both for BN microfibers and for BN/H composites, with average width between 17-27 µm and 36-39 µm, respectively. FTIR analyzes indicated that there were no chemical interactions between the two materials. The results of the TG and DTG thermogravimetric analysis of the composites showed mass loss in the range of 25-200°C and 200-290°C, associated with the individual thermal behavior of the hydrogel. The DSC curves for the composites showed two endothermic events, one in the range of -164 to -163.5 °C, attributed to the glass transition (Tg) of BN and the other between 109 to 117 °C, associated with Tg of the hydrogel superimposed on irreversible processes influenced by the presence of water in the composite. The tensile curves of BN microfiber membranes and composites presented similar profiles. They also showed an increase in rupture tension in relation to the dense film of BN. This increase was mainly attributed to the alignment of the microfibers during tensioning. The stress and deformation in the composites rupture decreased with the increase of the hydrogel content in the fibers, indicating a weak physical interaction between BN and the hydrogel. The degree of swelling of the spun composite membranes was shown to be dependent on the amount of hydrogel incorporated in the fibers, reaching a value of approximately 1427% for the composite membrane with mass ratio of BN/H (1:2). The possibility of producing membranes with different degrees of swelling, malleable, open promising prospects for applications in the biomedical area as materials with controlled drug release.
In this work, natural rubber microfibers (BN) and natural rubber-based composites incorporated with different amounts of hydrogel particles (H) were produced by solution blow spinning technique. The hydrogels used consisted of polyacrylamide (PAAm) and carboxymethylcellulose (CMC). Fibers with morphological structure in the form of ribbons were obtained both for BN microfibers and for BN/H composites, with average width between 17-27 µm and 36-39 µm, respectively. FTIR analyzes indicated that there were no chemical interactions between the two materials. The results of the TG and DTG thermogravimetric analysis of the composites showed mass loss in the range of 25-200°C and 200-290°C, associated with the individual thermal behavior of the hydrogel. The DSC curves for the composites showed two endothermic events, one in the range of -164 to -163.5 °C, attributed to the glass transition (Tg) of BN and the other between 109 to 117 °C, associated with Tg of the hydrogel superimposed on irreversible processes influenced by the presence of water in the composite. The tensile curves of BN microfiber membranes and composites presented similar profiles. They also showed an increase in rupture tension in relation to the dense film of BN. This increase was mainly attributed to the alignment of the microfibers during tensioning. The stress and deformation in the composites rupture decreased with the increase of the hydrogel content in the fibers, indicating a weak physical interaction between BN and the hydrogel. The degree of swelling of the spun composite membranes was shown to be dependent on the amount of hydrogel incorporated in the fibers, reaching a value of approximately 1427% for the composite membrane with mass ratio of BN/H (1:2). The possibility of producing membranes with different degrees of swelling, malleable, open promising prospects for applications in the biomedical area as materials with controlled drug release.
Descrição
Palavras-chave
Microfibras de borracha natural, Partículas de hidrogel, Compósitos, Fiação por sopro em solução (FSS), Natural rubber microfibers, Hydrogel particles, Composites, Solution Blow Spinning (SBS)