Made available in DSpace on 2014-12-17T15:01:32Z (GMT). No. of bitstreams: 1
AndreACP_DISSERT.pdf: 6190808 bytes, checksum: 21a983a9627b562fbe33e41da8ebdfd8 (MD5)
Previous issue date: 2013-08-09 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Polymer particles in the nanometer range are of fundamental interest today, especially when
used as carrier systems in the controlled release of drugs, cosmetics and nutraceuticals, as
well as in coating materials with magnetic properties. The main objective of the present study
concerns the production of submicron particles of poly (methyl methacrylate) (PMMA) by
crystallization of a polymer solution by thermally controlled cooling. In this work, PMMA
solutions in ethanol and 1-propanol were prepared at different concentrations (1% to 5% by
weight) and crystallized at different cooling rates (0.2 to 0.8 ? C / min) controlled linearly.
Analysis of particle size distribution (DLS / CILAS) and scanning electron microscopy
(SEM) were performed in order to evaluate the morphological characteristics of the produced
particles. The results demonstrated that it is possible to obtain submicron polymer perfectly
spherical particles using the technique discussed in this study. It was also observed that,
depending on the cooling rate and the concentration of the polymer solution, it is possible to
achieve high yield in the formation of submicron particles. In addition, preliminary tests were
performed in order to verify the ability of this technique to form particulated carrier material
with magnetic properties. The results showed that the developed technique can be an
interesting alternative to obtain polymer particles with magnetic properties / Part?culas polim?ricas formadas em escala nanom?trica s?o de fundamental interesse atualmente, principalmente quando utilizadas como sistemas carreadores na libera??o controlada de f?rmacos, cosm?ticos e nutrac?uticos, al?m do interesse pr?tico no recobrimento de materiais com propriedades magn?ticas. O principal objetivo do presente estudo diz respeito ? produ??o de part?culas submicrom?tricas de poli(metacrilato de metila) (PMMA) atrav?s da t?cnica de cristaliza??o de uma solu??o polim?rica por resfriamento controlado termicamente, segundo um perfil de taxa linear de resfriamento. Neste trabalho, solu??es de PMMA em etanol e 1-propanol foram preparadas em diferentes concentra??es (1% a 5% em massa) e cristalizadas em diferentes taxas de resfriamento (0,2 a 0,8 ?C/min) controladas linearmente. An?lises de distribui??o de part?culas (DLS/CILAS) e microscopia eletr?nica de varredura (MEV) foram realizadas com o intuito de avaliar as caracter?sticas morfol?gicas das part?culas formadas. Os resultados demonstraram que ? poss?vel obter part?culas polim?ricas submicrom?tricas com morfologia perfeitamente esf?rica utilizando a t?cnica abordada no presente estudo. Observou-se tamb?m que, a depender da taxa de resfriamento e da concentra??o da solu??o polim?rica, ? poss?vel ter alto rendimento na forma??o de part?culas submicrom?tricas. Adicionalmente, foram realizados testes preliminares com o prop?sito de verificar a capacidade desta t?cnica em formar part?culas carreadoras de materiais com propriedades magn?ticas. Os resultados permitiram concluir que a t?cnica estudada pode ser uma alternativa interessante na obten??o de part?culas polim?ricas com propriedades magn?ticas
| Identifer | oai:union.ndltd.org:IBICT/oai:repositorio.ufrn.br:123456789/15841 |
| Date | 09 August 2013 |
| Creators | Pereira, Andr? Anderson Costa |
| Contributors | CPF:29171156453, http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4787769D1, Oliveira, Jackson Ara?jo de, CPF:65331060587, http://lattes.cnpq.br/5058617634570704, Dariva, Cl?udio, CPF:54494206091, http://lattes.cnpq.br/6913799864277174, Oliveira, Humberto Neves Maia de, CPF:22179763468, http://lattes.cnpq.br/7302633941782540, Sousa, Elisa Maria Bittencourt Dutra de |
| Publisher | Universidade Federal do Rio Grande do Norte, Programa de P?s-Gradua??o em Engenharia Qu?mica, UFRN, BR, Pesquisa e Desenvolvimento de Tecnologias Regionais |
| Source Sets | IBICT Brazilian ETDs |
| Language | Portuguese |
| Detected Language | English |
| Type | info:eu-repo/semantics/publishedVersion, info:eu-repo/semantics/masterThesis |
| Format | application/pdf |
| Source | reponame:Repositório Institucional da UFRN, instname:Universidade Federal do Rio Grande do Norte, instacron:UFRN |
| Rights | info:eu-repo/semantics/openAccess |
Page generated in 0.0019 seconds