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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Novos mon?meros obtidos a partir do metacrilato de glicidila, bisfenol A e 4, 4 isopropilidenodicicloexanol : s?ntese, caracteriza??o estrutural e propriedades de comp?sitos para utiliza??o em resinas de restaura??o dental / New monomers obtained from glycidyl methacrylate, bisphenol A and 4,4 -isopropylidenedicyclohexanol: synthesis, structural characterization and properties of composites for use as dental composite resins

Reis, Jeanne Hemet?rio Cordeiro dos 28 September 2006 (has links)
Made available in DSpace on 2014-12-17T14:07:21Z (GMT). No. of bitstreams: 1 JeanneHCR.pdf: 2470228 bytes, checksum: 64b0abbe75bda944c8a21ce90a9f572b (MD5) Previous issue date: 2006-09-28 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Nowadays, composite resins are the direct restorative materials more important in dental clinical performance, due to their versatility and aesthetic excellence. Bis-GMA (2,2-bis[4(2-hydroxy-3-metacryloxypropoxy)phenil]propane) is the base monomer more frequently used in restorative composite resins. However, this monomer presents some disadvantages, such as high viscosity and two aromatic rings in its structure that can promote allergic reactions to the humans. In this work, the main purpose was to synthesize new monomers from glycidyl methacrylate to use in dental restorative materials. Structural characterization of the monomers was carried out through FTIR and NMR 1H, and eight composites were produced from the new monomers, by addition of silane-treated alumino silicate particles (inorganic filler) and a photocuring system (camphorquinone and ethyl 4-dimethylaminebenzoate). The composites were analyzed by environmental scanning electronic microscopy and the water sorption and solubility, compressive strength and elastic modulus were determined. A commercial composite resin [Z100 (3M)] was used to comparison effect. The new composites presented general characteristics similar to the commercial ones; however, they didn t present the properties expected. This behavior was attributed to the lower degree of monomer reaction and to the granulometry and size distribution of the mineral filler in the polymeric matrix / Atualmente, as resinas compostas constituem-se no material restaurador direto mais utilizado nas interven??es da cl?nica odontol?gica, dada a sua versatilidade e excel?ncia est?tica. O mon?mero mais freq?entemente usado na matriz polim?rica dessas resinas ? o Bis-GMA (2,2-bis[4(2-hidr?xi-3-metacriloiloxipropoxi)fenil]propano). No entanto, esse mon?mero apresenta algumas desvantagens, tais como elevada viscosidade e a presen?a de dois an?is arom?ticos em sua estrutura que podem causar rea??es al?rgicas ao organismo humano. Dessa forma, o objetivo principal deste trabalho foi sintetizar, a partir do metacrilato de glicidila, novos mon?meros para serem utilizados como componentes de poss?veis materiais restauradores dentais. A estrutura qu?mica dos mon?meros obtidos foi caracterizada pelas t?cnicas espectrosc?picas FTIR e RMN 1H, e oito comp?sitos foram preparados a partir dos novos mon?meros e part?culas silanizadas de silicato de alum?nio (carga inorg?nica), utilizando um sistema fotoativador/iniciador composto por canforoquinona e 4-dimetil amina benzoato de etila. Os comp?sitos foram analisados por microscopia eletr?nica de varredura ambiental e avaliados quanto ? sor??o e solubilidade em ?gua, resist?ncia ? compress?o e m?dulo de elasticidade. Para efeito de compara??o, utilizou-se a resina composta comercial Z100 (3M). Os novos comp?sitos preparados apresentaram caracter?sticas gerais semelhantes ?s resinas comerciais, entretanto, n?o se comportaram como esperado em rela??o ?s propriedades estudadas, o que foi atribu?do ao menor grau de rea??o dos mon?meros e ? granulometria e distribui??o da carga mineral na matriz polim?rica

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