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Abstract(s)
O polidimetilsiloxano, ou PDMS, é um material que vem, cada vez mais, sendo estudado devido às suas propriedades mecânicas interessantes, por ser um material polimérico hiperelástico capaz de alcançar grandes deformações, um bom isolante térmico e elétrico, muito leve e opticamente transparente, superfície hidrofóbica e biocompatível. Devido a essas características é muito utilizado em próteses na área biomédica, e na mecânica é utilizado como isolante térmico e elétrico, em juntas de vedação e sensores táteis. Por ter uma superfície hidrofóbica e antiadesiva é interessante o estudo da junção do PDMS com outros materiais. Muitos avanços vêm sendo incorporados acerca do PDMS, porém, são necessários estudos de propriedades de adesão do PDMS a outras superfícies. Para avaliação das propriedades do PDMS foram utilizadas técnicas numéricas e experimentais. Na parte experimental foi realizado um ensaio de cisalhamento em blocos de PDMS em juntas de sobreposição simples para espessura de 2 e 4mm, variando o tipo de adesivo utilizado e a velocidade de ensaio. Para avaliação numérica foram realizadas análises estatísticas e ensaios utilizando a técnica de correlação digital de imagem para obter dados desde o início até o final do ensaio. Verificou-se que a espessura do PDMS influencia na tensão máxima de cisalhamento, sendo que a região central do corpo de prova recebe a maior tensão. A velocidade também influencia na força máxima antes da rotura, e adesivo de cianoacrilato é mais eficiente do que uma cola epóxi. Com esse estudo foi possível observar que a correlação digital de imagem é uma técnica relativamente simples e eficiente no estudo do campo de deslocamentos e deformações de superfícies.
Polydimethylsiloxane, or PDMS, is a material that is increasingly being studied due to its interesting mechanical characteristics, being a hyperelastic polymeric material capable of achieving large deformations, a good thermal and electrical insulator, having low density and being optically transparent, with hydrophobic and biocompatible surface. Due to those characteristics is widely used in the biomedical and mechanical area, being used as thermal and electrical insulator, in sealing joints and tactile sensors. Because it has a hydrophobic and anti-adhesive surface it is interesting to study the combination of PDMS with other materials. Many advances have been incorporated into PDMS, however, studies of adhesion properties of PDMS to other surfaces is necessary. To evaluate PDMS properties, numerical techniques and experiments were used. In the experimental part a PDMS block shear test was performed in simple overlapping joints for 2 and 4mm thickness, varying the type of adhesive used and the test speed. For numerical evaluation, analyzes and tests were performed using a digital image correlation technique to obtain data from the beginning to the end of the test. It was found that the thickness of the PDMS influences the maximum shear stress, and the central region of the specimen receives the highest stress. Speed also influences the maximum force before rupture, and the cyanoacrylate adhesive is more efficient than an epoxy glue. The study showed that digital image correlation is a relatively simple and efficient technique in the study of the field of displacements and surface deformations.
Polydimethylsiloxane, or PDMS, is a material that is increasingly being studied due to its interesting mechanical characteristics, being a hyperelastic polymeric material capable of achieving large deformations, a good thermal and electrical insulator, having low density and being optically transparent, with hydrophobic and biocompatible surface. Due to those characteristics is widely used in the biomedical and mechanical area, being used as thermal and electrical insulator, in sealing joints and tactile sensors. Because it has a hydrophobic and anti-adhesive surface it is interesting to study the combination of PDMS with other materials. Many advances have been incorporated into PDMS, however, studies of adhesion properties of PDMS to other surfaces is necessary. To evaluate PDMS properties, numerical techniques and experiments were used. In the experimental part a PDMS block shear test was performed in simple overlapping joints for 2 and 4mm thickness, varying the type of adhesive used and the test speed. For numerical evaluation, analyzes and tests were performed using a digital image correlation technique to obtain data from the beginning to the end of the test. It was found that the thickness of the PDMS influences the maximum shear stress, and the central region of the specimen receives the highest stress. Speed also influences the maximum force before rupture, and the cyanoacrylate adhesive is more efficient than an epoxy glue. The study showed that digital image correlation is a relatively simple and efficient technique in the study of the field of displacements and surface deformations.
Description
Keywords
PDMS:Polidimetilsiloxano Cianoacrilato Epoxi Cisalhamento simples Sobreposição simples