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Previous issue date: 2014-04-11 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Thermal insulation is used to protect the heated or cooled surfaces by the low thermal conductivity materials. The rigid ricin polyurethane foams (PURM) are used for thermal insulation and depend on the type and concentration of blowing agent. Obtaining PURM occurs by the use of polyol, silicone, catalyst and blowing agent are pre -mixed, reacting with the isocyanate. The glass is reusable, returnable and recyclable heat insulating material, whose
time of heat dissipation determines the degree of relaxation of its structure; and viscosity determines the conditions for fusion, operating temperatures, annealing, etc. The production
of PURM composites with waste glass powder (PV) represents economical and renewable actions of manufacturing of thermal insulating materials. Based on these aspects, the study aimed to produce and characterize the PURM composites with PV, whose the mass percentages were 5, 10, 20, 30, 40 and 50 wt%. PURM was obtained commercially, while the PV was recycled from the tailings of the stoning process of a glassmaking; when the refining process was applied to obtain micrometer particles. The PURM + PV composites were studied taking into account the standard sample of pure PURM and the influence of the percentage of PV in this PURM matrix. The results of the chemical, physical and morphological characterization were discussed taking into account the difference in the microstructural morphology of the PURM+PV composites and the pure PURM, as well the results of the physicochemical, mechanical e thermophysical tests by values obtained of density, hardness, compressive strength, specific heat, thermal conductivity and diffusivity. In general, the structure of pure PURM showed large, elongated and regular pores, while PURM+PV composites showed irregular, small and rounded pores with shapeless cells. This
may have contributed to reducing their mechanical strength, especially for PURM - PV50. The hardness and density were found to have a proportional relationship with the PV content on PURM matrix. The specific heat, thermal diffusivity and thermal conductivity showed proportional relationship to each other. So, this has been realized that the increasing the PV content on PURM matrix resulted in the rise of diffusivity and thermal conductivity and the
decrease of the specific heat. However, the values obtained by the PURM composites were similar the values of pure PURM, mainly the PURM-PV5 and PURM-PV10. Therefore, these composites can be applied like thermal insulator; furthermore, their use could reduce the production costs and to preserve the environment / O isolamento t?rmico ? empregado na prote??o de superf?cies aquecidas ou resfriadas atrav?s de materiais de baixa condutividade t?rmica. As espumas r?gidas de poliuretano de mamona (PURM) s?o utilizadas para o isolamento t?rmico e dependem do tipo e da
concentra??o do agente de expans?o. O vidro ? um material isolante t?rmico reutiliz?vel, retorn?vel e recicl?vel, cujo tempo de dissipa??o do calor determina o grau de relaxa??o da sua estrutura e a viscosidade determina as condi??es de fus?o, temperaturas de trabalho, recozimento, etc. A produ??o de comp?sitos de PURM com rejeito de p? de vidro (PV) representa a??es econ?micas e renov?veis de fabrica??o de materiais isolantes t?rmicos. Baseado nestes aspectos, o trabalho objetivou a produ??o e caracteriza??o de comp?sitos de PURM com PV 5, 10, 20, 30, 40 e 50 % em massa. A PURM foi obtida comercialmente, enquanto que o PV foi reaproveitado do rejeito do processo de lapida??o de uma ind?stria
vidreira, cujo processo de refino foi utilizado para se obter part?culas microm?tricas. Os comp?sitos de PURM + PV foram estudados levando-se em considera??o o padr?o de refer?ncia PURM pura e a influ?ncia do percentual de PV desta matriz. Os resultados das
caracteriza??es qu?micas, f?sicas e morfol?gicas foram apresentadas e discutidas levando-se em considera??o a diferen?a na morfologia estrutural dos comp?sitos do PURM e da PURM pura e os valores obtidos nos ensaios de massa espec?fica, dureza, resist?ncia ? compress?o, condutividade t?rmica, calor espec?fico e difusividade t?rmica. Em geral, a estrutura da PURM pura apresentou poros regulares alongados e grandes, enquanto que os comp?sitos de
PURM + PV apresentaram poros irregulares, pequenos e arredondados com presen?a de c?lulas disformes, o que p?de ter contribu?do na redu??o de sua resist?ncia mec?nica, principalmente para a PURM-PV50. A dureza e a massa espec?fica revelaram ter uma rela??o proporcional com o teor de PV na matriz de PURM. O calor espec?fico, condutividade e difusividade t?rmica apresentaram rela??es proporcionais entre si. Assim, foi percebido que o aumento do teor de PV na matriz de PURM proporcionou um aumento da difusividade t?rmica e da condutividade t?rmica e a diminui??o do calor espec?fico. Contudo, os valores apresentados pelos comp?sitos de PURM foram similares aos valores da PURM pura, principalmente os comp?sitos PURM-PV5 e PURM-PV10. Portanto, estes comp?sitos podem ser aplicados como isolantes t?rmicos, al?m disto, o seu uso poderia reduzir os custos de fabrica??o e preservar o meio ambiente
| Identifer | oai:union.ndltd.org:IBICT/oai:repositorio.ufrn.br:123456789/15724 |
| Date | 11 April 2014 |
| Creators | Galv?o, ?lvaro C?sar Pontes |
| Contributors | CPF:13291085400, http://lattes.cnpq.br/7103009428184656, Silva, Gilson Garcia da, CPF:56634161453, http://lattes.cnpq.br/8681275097040450, Souza, Luiz Guilherme Meira de, CPF:25094955420, http://lattes.cnpq.br/0801747108308706, Mendes, Jos? Ubiragi de Lima |
| Publisher | Universidade Federal do Rio Grande do Norte, Programa de P?s-Gradua??o em Engenharia Mec?nica, UFRN, BR, Tecnologia de Materiais; Projetos Mec?nicos; Termoci?ncias |
| 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 |
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