Estudo das propriedades físicas de blendas de PVDF/Látex visando aplicação como biomaterial
Carregando...
Arquivos
Data
2005-08-26
Autores
Simões, Rebeca Delatore [UNESP]
Título da Revista
ISSN da Revista
Título de Volume
Editor
Universidade Estadual Paulista (Unesp)
Resumo
O principal objetivo deste trabalho de mestrado foi a obtenção e caracterização estrutural de um material com propriedades físico-químicas compatíveis com aquelas requeridas por um biomaterial. Filmes contendo diferentes volumes de látex de borracha natural em uma massa fixa de poli(fluoreto de vinilideno) (PVDF), na forma de pó foram fabricados por compressão/aquecimento de uma mistura de ambos os materiais sem o uso de qualquer solvente. Este é um fator importante considerando o uso destes filmes no futuro próximo como biomateriais em diferentes aplicações (indução do crescimento do tecido ósseo, por exemplo), uma vez que os solventes convencionais usados para dissolver o PVDF têm se mostrado tóxicos ao organismo humano. Os filmes foram submetidos a um tratamento via descarga corona de forma que amostras com e sem tal tratamento foram caracterizadas através das técnicas de espectroscopia vibracional via espalhamento Raman e absorção no infravermelho (FTIR), análise térmica via termogravimetria (TG), calorimetria exploratória diferencial (DSC) e análise dinâmico-mecânica (DMA) e microscopias ótica e eletrônica (MEV). As medidas termomecânicas mostraram que os filmes obtidos possuem características mecânicas similares àquelas encontradas no osso humano e boa estabilidade térmica considerando-se a aplicação desejada. As medidas via espectroscopia vibracional indicaram que o PVDF e o látex não interagem quimicamente, compondo uma blenda polimérica. Além disto, os resultados obtidos via micro-Raman mostraram que o aumento da quantidade de látex na blenda permite uma melhor dispersão deste látex na matriz de PVDF quando da produção dos filmes...
The main goal of this work was to obtain and characterize structurally a material with physical-chemical properties compatible with those required for a biomaterial. Films containing different volumes of latex of natural rubber in a fixed mass of poly (vinylidene fluoride) (PVDF) powder were fabricated by compressing/annealing a mixture of both materials without using any solvent. This is an important issue having in mind to use these films in the future as biomaterials in different applications (growing of the bone tissue, for instance) once the solvents used to dissolve the PVDF are toxic to human being. The films were submitted to a corona discharge treatment in a way that samples with and without such treatment were characterized using micro-Raman scattering and Fourier transform infrared absorption (FTIR) spectroscopies, thermo-mechanical techniques using thermogravimetry (TG), differential scanning calorimetry (DSC) and dynamical-mechanical analysis (DMA) and optical and scanning electron microscopies (SEM). The thermo-mechanical measurements revealed that the films present mechanical properties close to that found for the human bone and high thermal stability considering the desired applications. The vibrational spectroscopies showed that the latex and PVDF do not interact chemically leading to the formation of a polymeric blend. Besides, the results recorded using the micro-Raman technique revealed that the higher the amount of latex in the blend, the better the miscibility between both materials. In terms of morphology, the blend surface is formed by two domains: one is rougher and contains the latex well dispersed into the PVDF matrix while the other is smoother and contains both materials as well but in a less homogeneous dispersion. However, as the volume of latex is increased from 0.3 to 1.0 mL, the smoother domains become rarer to be found... (Complete abstract, click electronic address below)
The main goal of this work was to obtain and characterize structurally a material with physical-chemical properties compatible with those required for a biomaterial. Films containing different volumes of latex of natural rubber in a fixed mass of poly (vinylidene fluoride) (PVDF) powder were fabricated by compressing/annealing a mixture of both materials without using any solvent. This is an important issue having in mind to use these films in the future as biomaterials in different applications (growing of the bone tissue, for instance) once the solvents used to dissolve the PVDF are toxic to human being. The films were submitted to a corona discharge treatment in a way that samples with and without such treatment were characterized using micro-Raman scattering and Fourier transform infrared absorption (FTIR) spectroscopies, thermo-mechanical techniques using thermogravimetry (TG), differential scanning calorimetry (DSC) and dynamical-mechanical analysis (DMA) and optical and scanning electron microscopies (SEM). The thermo-mechanical measurements revealed that the films present mechanical properties close to that found for the human bone and high thermal stability considering the desired applications. The vibrational spectroscopies showed that the latex and PVDF do not interact chemically leading to the formation of a polymeric blend. Besides, the results recorded using the micro-Raman technique revealed that the higher the amount of latex in the blend, the better the miscibility between both materials. In terms of morphology, the blend surface is formed by two domains: one is rougher and contains the latex well dispersed into the PVDF matrix while the other is smoother and contains both materials as well but in a less homogeneous dispersion. However, as the volume of latex is increased from 0.3 to 1.0 mL, the smoother domains become rarer to be found... (Complete abstract, click electronic address below)
Descrição
Palavras-chave
Analise termica, Microscopia eletronica de varredura, Borracha natural, Espalhamento - Raman, Natural rubber, Micro-raman scattering, Thermal analysis, Scanning electronic microscopy
Como citar
SIMÕES, Rebeca Delatore. Estudo das propriedades físicas de blendas de PVDF/Látex visando aplicação como biomaterial. 2005. 74 f. Dissertação (mestrado) - Universidade Estadual Paulista, Faculdade de Ciências de Bauru, 2005.