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Papers by Wanderley Da Costa

Journal of Adhesion Science and Technology, 2012

Butyl mastic is used in a number of industrial areas and in particular in the production of adhes... more Butyl mastic is used in a number of industrial areas and in particular in the production of adhesives. The performance of this material can be improved by using ionizing radiation. In this work we showed that the shear forces in butyl mastic were modified when the material was exposed to radiation, and as a consequence the adhesion strength was increased.

e sem a presença de sílica ativa. O resultado foi um aumento em 8,2% das tensões de cisalhamento ... more e sem a presença de sílica ativa. O resultado foi um aumento em 8,2% das tensões de cisalhamento entre o adesivo e seu substrato após a cura quando na formulação estava presente a sílica ativa. Este resultado pode ser utilizado como contribuição para o conhecimento dos promotores de adesão em adesivos de silicone. Palavras chave: silicona, sílica ativa, adesivo selante.

The focus of this dissertation was the search of experimental facts to confirm or refuse that mag... more The focus of this dissertation was the search of experimental facts to confirm or refuse that magnetically conditioned water reduces incrustation in industrial equipments. The aim of this work was to assess three identical testing devices assembled with centrifugal pump, storage tank and incrustation test chamber. One of them received a magnetic conditioner. All of them received the same charge of salt solution that simulated industrial water. The device with magnetic conditioner and other one were operated only with algaecide addition. The third device received the algaecide and anticorrosion additives. They were operated along fifty six days uninterruptedly in the same environment. The quality of the water and the degree of deposition on test metal coupons were measured throughout the test time. The aspect of the deposits on metal coupons was scanned by scanning electron microscopy. The results allow us to accept with high level of confidence that the magnetic treatment of water e...

Confins, 2014

dossiê Desafios do pré-sal dossiê Desafios do pré-sal RESUMO O alargamento do entorno regional e ... more dossiê Desafios do pré-sal dossiê Desafios do pré-sal RESUMO O alargamento do entorno regional e estratégico do Brasil corresponde à nova escala de interesses, oportunidades e influência de um país que se consolida como potência econômica no cenário internacional e que tem feito do domínio e da exploração dos recursos do mar uma das suas mais promissoras fontes de riqueza. A inflexão nos rumos do desenvolvimento do país na direção do Atlântico Sul nos últimos trinta anos expressa a conjugação de vetores de largo espectro e longa duração. Essa conquista vem sendo processada pela aplicação bem-sucedida de estratégia que combina ações contínuas no campo diplomático, esforço nacional de pesquisa na ampla área das ciências do mar e investimentos que visam fortalecer a capacidade militar do país para fazer frente aos seus desafios de segurança & defesa em geral e no Atlântico Sul em particular.

Journal of Adhesion Science and Technology, 2016

Dissertação de mestrado, 2006

Polímeros, 2011

A pesquisa demonstra como é o comportamento de dois materiais conhecidos comercialmente como mast... more A pesquisa demonstra como é o comportamento de dois materiais conhecidos comercialmente como mastic em relação às forças de cisalhamento de selantes. No mercado existem dois tipos de mastic, um da família de silicones e outro da borracha butílica. A pesquisa teve o objetivo de esclarecer junto à receita federal e ao mercado, que as propriedades dos dois tipos são muito diferentes, apesar de ambos sofrerem um processo de cura. Com o tempo há aumento das forças de coesão e adesão de ambos, o que evidencia o processo de cura.

Adhesives are products that can keep materials together by bonds between the surfaces. Sealants a... more Adhesives are products that can keep materials together by bonds between the surfaces. Sealants are products that can keep filled a space between two surfaces, through a barrier that is configured as a "bridge" between the two surfaces. The mastic is a product made of a mixture of substances with the primary butyl polymer, with the consistency of a mass not dried that can be used as a sealant. The polysiloxane, also known as silicone are the most important synthetic polymers with inorganic structure, and are matrices of silicone adhesive sealants. To demonstrate the behavior of the adhesive forces of these products under different conditions, we used five different techniques. These products were subjected to two different conditions to verify the behavior of adhesion, one at the environmental condition and another under the ionizing radiation. The results showed not only differences between products (silicone and mastic), but also that the adhesive forces have different behaviors under the conditions which the samples were subjected. With this was reached the goal of this study that aspired show the differences between the mastic and silicone, this last one is often considered-erroneously-the same as mastic. Thus it was proven that: 1. silicone can be regarded as an adhesive and a sealant at ambient conditions, 2. mastic improves substantially adhesion in an environment of ionizing radiation and this property can be an excellent alternative to the adhesive market.

Modern Chemistry & Applications, 2016

This research presents a new proposal to water based adhesives manufacturing process, utilizing m... more This research presents a new proposal to water based adhesives manufacturing process, utilizing magnetic conditioning. Using this technique it is possible to increase the adhesion capacity between the adhesive and the substrate. The formulation proved to be efficient after the magnetic conditioning and without reactivation which also generated a significant alteration of the viscosity which was 350 mPa.s to 1100 mPa.s, without the necessity of the addition of any other product as thickener. If we compare the same adhesive formulation, with magnetic conditioning and without reactivation and an adhesive without magnetic conditioning and with reactivation, the increase of adhesion capacity was 42.11%, in the magnetically conditioning. When we verify the shear stresses in adhesive without reactivation, without magnetic conditioning and irradiated at 15 kGy we found an average of 3.29 × 10 5 Pa in the shear stresses, that is 2.16 times lower, compared with the average value found in the test specimens, magnetically conditioned, without reactivation, which was 7.11 × 10 5 Pa. If the non-ionizing radiation dose of 25 kGy passes, the shear stresses decrease considerably, regardless of the process, with or without magnetic conditioning has the consequence of breaking of the bonds of the polymeric matrix with the test specimens interface.

Polimeros, 2011

This study reveals the response to shear forces for two materials known as mastic. There are two ... more This study reveals the response to shear forces for two materials known as mastic. There are two kinds of mastic in the market, one of the silicone family and another made with butyl rubber. The aim was to demonstrate to the Inland Revenue and to the market that these materials exhibit very distinct properties, although both undergo the curing process. As time goes by, there is an increase in the forces of cohesion and adhesion for both types of mastic, which is evidence of the curing process.

Journal of Adhesion Science and Technology, 2012

Butyl mastic is used in a number of industrial areas and in particular in the production of adhes... more Butyl mastic is used in a number of industrial areas and in particular in the production of adhesives. The performance of this material can be improved by using ionizing radiation. In this work we showed that the shear forces in butyl mastic were modified when the material was exposed to radiation, and as a consequence the adhesion strength was increased. This was done by comparing the shear forces of butyl mastic before and
after the exposure to ionizing radiation. The result was an increase of 440% of the average shear strength between the sealant and the substrate after the irradiation. This work can be considered as an important contribution to the field of butyl mastic. sealants and adhesives.

Journal of Adhesion Science and Technology, 2012

Butyl mastic is used in a number of industrial areas and in particular in the production of adhes... more Butyl mastic is used in a number of industrial areas and in particular in the production of adhesives. The performance of this material can be improved by using ionizing radiation. In this work we showed that the shear forces in butyl mastic were modified when the material was exposed to radiation, and as a consequence the adhesion strength was increased.

e sem a presença de sílica ativa. O resultado foi um aumento em 8,2% das tensões de cisalhamento ... more e sem a presença de sílica ativa. O resultado foi um aumento em 8,2% das tensões de cisalhamento entre o adesivo e seu substrato após a cura quando na formulação estava presente a sílica ativa. Este resultado pode ser utilizado como contribuição para o conhecimento dos promotores de adesão em adesivos de silicone. Palavras chave: silicona, sílica ativa, adesivo selante.

The focus of this dissertation was the search of experimental facts to confirm or refuse that mag... more The focus of this dissertation was the search of experimental facts to confirm or refuse that magnetically conditioned water reduces incrustation in industrial equipments. The aim of this work was to assess three identical testing devices assembled with centrifugal pump, storage tank and incrustation test chamber. One of them received a magnetic conditioner. All of them received the same charge of salt solution that simulated industrial water. The device with magnetic conditioner and other one were operated only with algaecide addition. The third device received the algaecide and anticorrosion additives. They were operated along fifty six days uninterruptedly in the same environment. The quality of the water and the degree of deposition on test metal coupons were measured throughout the test time. The aspect of the deposits on metal coupons was scanned by scanning electron microscopy. The results allow us to accept with high level of confidence that the magnetic treatment of water e...

Confins, 2014

dossiê Desafios do pré-sal dossiê Desafios do pré-sal RESUMO O alargamento do entorno regional e ... more dossiê Desafios do pré-sal dossiê Desafios do pré-sal RESUMO O alargamento do entorno regional e estratégico do Brasil corresponde à nova escala de interesses, oportunidades e influência de um país que se consolida como potência econômica no cenário internacional e que tem feito do domínio e da exploração dos recursos do mar uma das suas mais promissoras fontes de riqueza. A inflexão nos rumos do desenvolvimento do país na direção do Atlântico Sul nos últimos trinta anos expressa a conjugação de vetores de largo espectro e longa duração. Essa conquista vem sendo processada pela aplicação bem-sucedida de estratégia que combina ações contínuas no campo diplomático, esforço nacional de pesquisa na ampla área das ciências do mar e investimentos que visam fortalecer a capacidade militar do país para fazer frente aos seus desafios de segurança & defesa em geral e no Atlântico Sul em particular.

Journal of Adhesion Science and Technology, 2016

Dissertação de mestrado, 2006

Polímeros, 2011

A pesquisa demonstra como é o comportamento de dois materiais conhecidos comercialmente como mast... more A pesquisa demonstra como é o comportamento de dois materiais conhecidos comercialmente como mastic em relação às forças de cisalhamento de selantes. No mercado existem dois tipos de mastic, um da família de silicones e outro da borracha butílica. A pesquisa teve o objetivo de esclarecer junto à receita federal e ao mercado, que as propriedades dos dois tipos são muito diferentes, apesar de ambos sofrerem um processo de cura. Com o tempo há aumento das forças de coesão e adesão de ambos, o que evidencia o processo de cura.

Adhesives are products that can keep materials together by bonds between the surfaces. Sealants a... more Adhesives are products that can keep materials together by bonds between the surfaces. Sealants are products that can keep filled a space between two surfaces, through a barrier that is configured as a "bridge" between the two surfaces. The mastic is a product made of a mixture of substances with the primary butyl polymer, with the consistency of a mass not dried that can be used as a sealant. The polysiloxane, also known as silicone are the most important synthetic polymers with inorganic structure, and are matrices of silicone adhesive sealants. To demonstrate the behavior of the adhesive forces of these products under different conditions, we used five different techniques. These products were subjected to two different conditions to verify the behavior of adhesion, one at the environmental condition and another under the ionizing radiation. The results showed not only differences between products (silicone and mastic), but also that the adhesive forces have different behaviors under the conditions which the samples were subjected. With this was reached the goal of this study that aspired show the differences between the mastic and silicone, this last one is often considered-erroneously-the same as mastic. Thus it was proven that: 1. silicone can be regarded as an adhesive and a sealant at ambient conditions, 2. mastic improves substantially adhesion in an environment of ionizing radiation and this property can be an excellent alternative to the adhesive market.

Modern Chemistry & Applications, 2016

This research presents a new proposal to water based adhesives manufacturing process, utilizing m... more This research presents a new proposal to water based adhesives manufacturing process, utilizing magnetic conditioning. Using this technique it is possible to increase the adhesion capacity between the adhesive and the substrate. The formulation proved to be efficient after the magnetic conditioning and without reactivation which also generated a significant alteration of the viscosity which was 350 mPa.s to 1100 mPa.s, without the necessity of the addition of any other product as thickener. If we compare the same adhesive formulation, with magnetic conditioning and without reactivation and an adhesive without magnetic conditioning and with reactivation, the increase of adhesion capacity was 42.11%, in the magnetically conditioning. When we verify the shear stresses in adhesive without reactivation, without magnetic conditioning and irradiated at 15 kGy we found an average of 3.29 × 10 5 Pa in the shear stresses, that is 2.16 times lower, compared with the average value found in the test specimens, magnetically conditioned, without reactivation, which was 7.11 × 10 5 Pa. If the non-ionizing radiation dose of 25 kGy passes, the shear stresses decrease considerably, regardless of the process, with or without magnetic conditioning has the consequence of breaking of the bonds of the polymeric matrix with the test specimens interface.

Polimeros, 2011

This study reveals the response to shear forces for two materials known as mastic. There are two ... more This study reveals the response to shear forces for two materials known as mastic. There are two kinds of mastic in the market, one of the silicone family and another made with butyl rubber. The aim was to demonstrate to the Inland Revenue and to the market that these materials exhibit very distinct properties, although both undergo the curing process. As time goes by, there is an increase in the forces of cohesion and adhesion for both types of mastic, which is evidence of the curing process.

Journal of Adhesion Science and Technology, 2012

Butyl mastic is used in a number of industrial areas and in particular in the production of adhes... more Butyl mastic is used in a number of industrial areas and in particular in the production of adhesives. The performance of this material can be improved by using ionizing radiation. In this work we showed that the shear forces in butyl mastic were modified when the material was exposed to radiation, and as a consequence the adhesion strength was increased. This was done by comparing the shear forces of butyl mastic before and
after the exposure to ionizing radiation. The result was an increase of 440% of the average shear strength between the sealant and the substrate after the irradiation. This work can be considered as an important contribution to the field of butyl mastic. sealants and adhesives.