• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 5
  • 4
  • Tagged with
  • 12
  • 12
  • 4
  • 4
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 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

High Performance Electronics on Flexible Silicon

Sevilla, Galo T. 09 1900 (has links)
Over the last few years, flexible electronic systems have gained increased attention from researchers around the world because of their potential to create new applications such as flexible displays, flexible energy harvesters, artificial skin, and health monitoring systems that cannot be integrated with conventional wafer based complementary metal oxide semiconductor processes. Most of the current efforts to create flexible high performance devices are based on the use of organic semiconductors. However, inherent material's limitations make them unsuitable for big data processing and high speed communications. The objective of my doctoral dissertation is to develop integration processes that allow the transformation of rigid high performance electronics into flexible ones while maintaining their performance and cost. In this work, two different techniques to transform inorganic complementary metal-oxide-semiconductor electronics into flexible ones have been developed using industry compatible processes. Furthermore, these techniques were used to realize flexible discrete devices and circuits which include metal-oxide-semiconductor field-effect-transistors, the first demonstration of flexible Fin-field-effect-transistors, and metal-oxide-semiconductors-based circuits. Finally, this thesis presents a new technique to package, integrate, and interconnect flexible high performance electronics using low cost additive manufacturing techniques such as 3D printing and inkjet printing. This thesis contains in depth studies on electrical, mechanical, and thermal properties of the fabricated devices.
2

Effect of Liquid Contamination on Hermeticity and Seal Strength of Flexible Pouches with LLDPE Sealant

Delle Cese, Francesca 01 March 2014 (has links) (PDF)
Flexible packaging is a growing successful market and the majority of flexible package applications are for the food industry. The demand for process optimization and reduced production costs, has led to an increase in flexible packaging. However, fast production lines can result in contamination in the seal area. For flexible food packaging, contamination is considered any food particle or substance trapped in the seal area. Current quality control processes can detect contamination in the seal area, but it is not determined if seal contamination effects seal quality. Oil-based and sodium based snack foods are two common categories that can be packaged on a horizontal flow film and seal (HFFS) flow-wrap machine. The study uses vegetable oil and a salt water solution to simulate the effect of liquid contamination along the T-point of flexible pouches made on an HFFS. The T-point refers to where the fin seal meets the end seal and requires the seal jaw to seal through four layers of film, which is the most difficult point to seal. The study tests a combination of different sealing temperatures and dwell time to determine the optimal sealing condition for a hermetic seal. A quality hermetic seal provides an enclosed seal with no leaks due to successful polymer chain entanglement between the two sealant layers. The different test categories of the study are non-contaminated (control), salt water solution for salt based foods, and vegetable oil for oil-based foods. Given the test parameters of the study, 140⁰C sealing temperature and 0.3 seconds dwell time are considered to be the optimal sealing condition for all three test categories. For Phase 1 of the study, salt water has a lower hermeticity pass rate compared to vegetable oil and non-contaminated seals. In addition, the effect of refrigerated storage temperature and ambient storage temperature did not show to be significant for any of the test categories. However, refrigerated conditions showed a higher hermeticity pass rate, but it was not statistically different. The findings for seal strength indicated no test category had higher or lower seal strength over the 14 day test period. Overall, the study shows there is no effect of liquid contaminant on hermeticity and seal strength for flexible film with LLDPE sealant layer.
3

Effect of flexible substrate surface modification on inkjet printed colloidal drop evaporation and deposition

Gawande, Sailee Sanjay. January 2009 (has links)
Thesis (M.S.)--State University of New York at Binghamton, Thomas J. Watson School of Engineering and Applied Science, Department of Mechanical Engineering, 2009. / Includes bibliographical references.
4

Comparação da implementação da melhoria contínua em duas fábricas de embalagens flexíveis

André Hernandes 02 July 2011 (has links)
As empresas estão se deparando com um mercado mais competitivo a cada dia, e em função desta realidade necessitam melhorar seus processos internos para agregar valor aos seus produtos e serviços e eliminar desperdícios para, desta forma, apresentar para o mercado maior qualidade e menor custo. Este trabalho tem como objetivo comparar a aplicação da melhoria contínua (kaizen) em duas empresas fabricantes de embalagens flexíveis e os resultados obtidos em cada uma delas em função da utilização ou não de um procedimento para a implementação. Numa empresa o procedimento utilizado foi o PDCA, suportado pelas ferramentas da qualidade em cada uma de suas etapas, enquanto que, na outra empresa, não foi aplicado procedimento algum e sim ações com base intuitiva não estruturada e com uma formatação definida pela própria empresa. Os resultados observados nas empresas objeto de estudo revelaram que a aplicação da melhoria contínua incrementa o desempenho das empresas, mas para o sucesso de sua implementação é fundamental que a condução seja baseada em procedimento consagrado para assegurar a sua eficácia. / Companies are facing a more competitive market each day, and in light of this reality need to improve their internal pocesses to add value to their products and services and to eliminate waste, thus presenting to market higher quality and lower cost. This study aims to compare the application of continuous improvement (kaizen) in two manufacturers of flexible packing and results in each depending on the use or absence of a procedure for implementation. In undertaking the procedure used was the PDCA, supported by the tools of quality in each of its stages, while in another company, the procedure was not applied, but some actions based on unstructured and intuitive with a format defined by the company. The result observed among in the companies under study, revealed that application of continuous improvement increases their performance but to the success of its implementation is essential that the conduct is based on established procedure to ensure their effectiveness.
5

Desafios e potenciais soluções para reciclagem de embalagens plásticas flexíveis pós-consumo no Brasil /

Yugue, Eduardo Tadashi January 2020 (has links)
Orientador: Sandro Donnini Mancini / Resumo: Este trabalho visa tratar da reciclagem das embalagens plásticas flexíveis pós-consumo no Brasil, apresentando o panorama atual, os principais desafios e dificuldades para a reciclagem e, potenciais soluções tecnológicas disponíveis ou em desenvolvimento no Brasil e em outros países. Dados indicam que o volume de embalagens plásticas flexíveis pós-consumo seguirá crescendo nos próximos anos no Brasil. Atualmente uma parte deste tipo de material está sendo descartado de forma inadequada em aterros sanitários ou então descartadas aleatoriamente em lixões à céu aberto, com impacto negativo ao meio ambiente. Ao não ser reciclado, há a necessidade de extração contínua de recursos naturais, para a continuidade do processo produção-consumo. É necessário estabelecer ações que permitam um ciclo em que recursos extraídos da natureza possam voltar à produção de novos bens ao final de cada ciclo, estabelecendo as bases da economia circular. O trabalho foi realizado a partir de revisão bibliográfica, leitura de artigos técnico-científicos, participação em reuniões, visitas, consultas, entrevistas e acesso a “sites” da internet envolvendo órgãos públicos, associações de classes e empresas pertencentes à cadeia de produção de plásticos, conversão de embalagem, coleta seletiva e à reciclagem de embalagens plásticas. Como resultados, este trabalho reporta a necessidade de aplicação do conceito de eco-design no projeto de novas embalagens, tecnologia para separação automática de materiais, del... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre
6

Navigating Extremes: Advancing 3D-IC with Flexible Glass for Harsh Environments

Joo Min Kim (18838408) 17 June 2024 (has links)
<p dir="ltr">The rapid evolution of semiconductor technology, driven by the limitations of Moore's Law, necessitates innovative approaches to enhance device performance and miniaturization. This thesis explores the advancement of three-dimensional integrated circuits (3D-ICs) using flexible glass-based substrates, focusing on their application in extreme environments. Flexible glass emerges as a promising material for 3D-IC packaging due to its superior electrical insulation, thermal stability, chemical resistance, and mechanical strength. These properties are critical for maintaining device reliability and functionality under harsh conditions such as high temperatures, humidity, and radiation. Their unique properties make them particularly suited for applications in aerospace, military, and automotive industries, where electronics must endure severe operational environments. The research presented in this thesis provides a comprehensive examination of the processes involved in fabricating flexible glass-based 3D-ICs, detailing methodologies for integrating semiconductor components onto a flexible glass substrate using common platform technology (CPT). This approach ensures compatibility across diverse systems and enhances the scalability and cost-effectiveness of 3D-IC solutions. Experimental results indicate that 3D-ICs incorporating flexible glass substrates exhibit enhanced functionality and durability. This study underscores the transformative potential of flexible glass in revolutionizing the design and performance of future electronic systems, ensuring their operability and longevity in demanding settings. By addressing the challenges of traditional packaging materials, flexible glass represents a significant advancement in 3D-IC technology, promising to broaden the operational landscape of electronic devices and change how they are deployed across various high-stakes fields.</p>
7

ANÁLISE DE INDICADORES DE DESEMPENHO PARA INDÚSTRIAS DE EMBALAGENS FLEXÍVEIS.

Medeiros, Alessandro Araújo 10 September 2013 (has links)
Made available in DSpace on 2016-08-10T10:40:20Z (GMT). No. of bitstreams: 1 ALESSANDRO ARAUJO MEDEIROS.pdf: 2454802 bytes, checksum: d8f8ec98bf26f15e624e8fbf4aa62488 (MD5) Previous issue date: 2013-09-10 / In last few years the industry has become a lot more competitive, forcing companies to improve their productive performances. The study shows how a production process of a Flexible Packaging Industry can improve it using the performance indicators. The research developed several performance indicators to various departments. Adopting the methodology of research-action study has taken interventional actions and continuous in whole research process. The result improvements has concentrated on reduces waste, overtime and production increase. So, this work consolidates a methodology implementation and performance indicators developing that support obtain better performances in a flexible packaging industry. / Nos últimos anos, a indústria se tornou muito mais competitiva, obrigando as empresas melhorarem seus desempenhos produtivos. Este trabalho apresenta uma análise de indicadores de desempenho para uma indústria de embalagens flexíveis. O estudo mostra como um processo produtivo de uma indústria de embalagens flexíveis pode melhorar, por meio da utilização de indicadores de desempenho. Na pesquisa foram desenvolvidos vários indicadores de desempenho para os departamentos de extrusão e pintura da organização submetida ao estudo, mediante a adoção de uma abordagem investigativa de pesquisa-ação. A melhoria dos resultados se concentrou em redução de desperdícios, horas extras e aumento da produtividade. Nesse sentido, o trabalho consolidou uma metodologia de implantação e desenvolvimento de indicadores de desempenho que podem auxiliar na obtenção da melhoria de desempenho em uma indústria do setor de embalagens plásticas.
8

Avaliação dos efeitos da radiação por feixe de elétrons na resistência de embalagens a Lasioderma serricorne, Plodia interpunctella e Sitophilus zeamais / Radiation effects evaluation for electrons sheaf in packages resistance in a Lasioderma serricorne, Plodia interpunctella and Sitophilus zeamais

Alves, Juliana Nazaré 16 August 2011 (has links)
As pragas de produtos armazenados constituem um problema para o homem, depreciando produtos e causando prejuízos econômicos. Dentre estas pragas temos o Lasioderma serricorne (F. 1792), Sitophilus zeamais (M. 1855) e Plodia interpunctella (H. 1813) conhecidos por infestar produtos armazenados como: grãos, farelos, farinhas, café, fumo, frutas secas e especiarias. Essas pragas perfuram e adentram as embalagens, ovipositando sobre o substrato. Neste contexto a embalagem desempenha um papel fundamental, impedindo o contato e proliferação de pragas no produto acondicionado. Assim, para proteger o produto acondicionado e prolongar a sua vidaútil a embalagem deve apresentar boa resistência mecânica à tração e à perfuração, boa selabilidade, boas propriedades de barreira e não transferir odores nem sabores estranhos ao produto acondicionado. A radiação ionizante pode causar mudanças estruturais nos materiais poliméricos de embalagens, essas mudanças são causadas pelos processos de cisão e reticulação das cadeias poliméricas. Estes são processos concorrentes e a predominância de um sobre o outro depende da estrutura química do polímero, das condições da irradiação e de fatores específicos do material que irá absorver a energia. Este trabalho teve o objetivo de avaliar as mudanças nas propriedades mecânicas de estruturas de embalagem utilizadas para armazenar granola, barra de cereais e macarrão, bem como suas resistências a perfuração por L. serricorne, P. interpunctella e S. zeamais, quando submetidas a radiação por feixe de elétrons. Na metodologia foram utilizadas cinco estruturas de embalagem comercialmente utilizadas para armazenar granola, barra de cereais e macarrão compostas por (Polipropileno bi-orientado metalizado/Polipropileno bi-orientado coextrusado - BOPPmet/BOPP 50 &mu;m), (Polipropileno bi-orientado/Polipropileno - BOPP/PP 50 &mu;m), Poli(tereftalato de etileno) metalizado/Polipropileno bi-orientado coextrusado - PETmet/BOPP 32 &mu;m), Poli(tereftalato de etileno)/Polipropileno - PET/PP1 72 &mu;m) e Poli(tereftalato de etileno)/Polipropileno - PET/PP2 32 &mu;m). As estruturas de embalagens foram submetidas à doses de radiação entre 0, 10, 20 e 60 kGy, em um acelerador de elétrons de 1,5 MeV, 25 mA e 37,5 kW, à taxa de dose de 11,22 kGy/s, temperatura ambiente e presença de ar. Oito dias, 2 meses e 6 meses após as irradiações foram realizados ensaios mecânicos de resistência a tração e elongação na ruptura, resistência da selagem e resistência à perfuração, todos com base nas suas respectivas normas ASTM [35]. Os ensaios de perfuração por insetos foram realizados em sala climatizada, onde amostras irradiadas nas doses de 0, 10, 20 e 60 kGy foram seladas contendo 40 g de granola, 40 g de macarrão e barra de cereais em número de nove por ensaio, e divididas igualmente em três caixas plásticas teladas por dose estudada. Em cada caixa foram adicionados 20 adultos de cada inseto em por 60 dias, quando as embalagens foram avaliadas para verificação de possíveis perfurações. As diferenças entre os resultados das amostras foram estatisticamente avaliados pelo método ANOVA (p<0,05). Os resultados mostraram que quanto à resistência a perfuração por L. serricorne, P. interpunctella e S. zeamais as estruturas poliméricas avaliadas apresentaram baixa resistência à perfuração por insetos antes e após o tratamento. BOPPmet/BOPP (50 &mu;m), PETmet/BOPP (32 &mu;m), PET/PP1 (72 &mu;m) e PET/PP2 (32 &mu;m) apresentaram perdas significativas nas estruturas nas propriedades mecânicas estudadas. O BOPP/PP (50 &mu;m) apresentou o melhor conjunto de respostas nas propriedades mecânicas ao tratamento por radiação com feixe de elétrons em doses de até 10 kGy. Dentre as propriedades mecânicas avaliadas a selagem foi a mais afetada pela radiação ionizante, tendo apresentado, em geral, perdas crescentes com a dose de radiação. / The plagues of stored products consist of a man problem, depreciating products and causing economical damages. Among these curses we have Lasioderma serricorne (F. 1792), Sitophilus zeamais (M. 1855) and Plodia interpunctella (H. 1813) known by infesting stored products as: grains, brans, flours, coffee, tobacco, dried fruits and spices. These curses perforate and penetrate the packages, ovipositing over the substratum. In this context the package plays a fundamental part, preventing the contact and curses proliferation in the packed product. So, to protect the packed product and to prolong its shelf life, the package should have good mechanical resistance to tension and perforation, good sealing, good barrier properties and should not transfer odors nor strange flavors to the packed product. The ionizing radiation can cause structural changes in polymer packages, these changes are caused by the scission processes and reticulation of the polymers chains. These are concurrent processes and the predominance of one over the other depends on the chemical structure of the polymer, the irradiation conditions and specific factors of the material that will absorb the energy. This work had the objective to evaluate the changes in mechanical properties of package structures used to store granola, cereal bar and pasta, as well as its resistance to perforation by L. serricorne, P. interpunctella and S. zeamais, when submitted to electrons sheaf radiation. In this methodology were used five structures of commercially utilized packages to store granola, cereal bar and pasta composed by (Polypropylene bi-oriented metallic/Polypropylene bi-oriented coextruded - BOPPmet/BOPP 50 &mu;m), (Polypropylene bi-oriented/Polypropylene - BOPP/PP 50 &mu;m), Poli (ethylene terephthalate) metallic/Polypropylene bi-oriented coextruded - PETmet/BOPP 32 &mu;m), Poli (ethylene terephthalate) /Polypropylene - PET/PP1 72 &mu;m), Poli (ethylene terephthalate)/Polypropylene - PET/PP2 32 &mu;m). The structures of packaging were submitted to radiation doses between 0, 10, 20 and 60 kGy, in one electron accelerator of 1,5 M and V, 25 mA and 37,5 kW, dose tax of 11,22 kGy / s, room temperature and air presence . Eight days, Two and Six months after irradiations, mechanical resistance experiment were accomplished to tension and elongating in rupture, sealing resistance and perforation resistance, all based in respective ASTM norms. The perforation experiment by insects were realized in an acclimatized room, where irradiated samples in doses of 0, 10, 20 and 60 kGy were sealed containing 40 g of granola, 40 g of pasta and cereal bar in number of nine by experiment, and equally divided in three plastic screened boxes by studied dose. In each box 20 adults of each insect were added in for 60 days, when the packages were evaluated to verify possible perforations. The differences between the sample results were statistically evaluated by ANOVA (p<0.05). The results showed that concerning the perforation resistance by L. serricorne, P. interpunctella and S. zeamais the polymeric structures evaluated showed low resistance by insects perforation before and after the treatment. BOPPmet/BOPP (50 &mu;m), PETmet/BOPP (32 &mu;m), PET/PP1 (72 &mu;m) and PET/PP2 (32 &mu;m) structures showed significant losses in mechanical properties studied. The BOPP/PP (50 &mu;m) showed the best set of answers in mechanical properties to the radiation treatment with electrons sheaf up to 10 kGy doses. Among the mechanical properties evaluated, sealing was the most affected by ionizing radiation, has shown, in general, increasing losses with radiation dose.
9

Toward an energy harvester for leadless pacemakers

Deterre, Martin 09 July 2013 (has links) (PDF)
This work consists in the development and design of an energy harvesting device to supply power to the new generation pacemakers, miniaturized leadless implants without battery placed directly in heart chambers. After analyzing different mechanical energy sources in the cardiac environment and associated energy harvesting mechanisms, a concept based on regular blood pressure variation stood out: an implant with a flexible packaging that transmits blood forces to an internal transducer. Advantages compared to traditional inertial scavengers are mainly: greater power density, adaptability to heartbeat frequency changes and miniaturization potential. Ultra-flexible 10-µm thin metal bellows have been designed, fabricated and tested. These prototypes acting as implant packaging that deforms under blood pressure actuation have validated the proposed harvesting concept. A new type of electrostatic transducer (3D multi-layer out-of-plane overlap structure with interdigitated combs) has been introduced and fully analyzed. Promising numerical results and associated fabrication processes are presented. Also, large stroke optimized piezoelectric spiral transducers including their complex electrodes patterns have been studied through a design analysis, numerical simulations, prototype fabrication and experimental testing. Apower density of 3 µJ/cm3/cycle has been experimentally achieved. With further addressed developments, the proposed device should provide enough energy to power autonomously and virtually perpetually the next generation of pacemakers.
10

Avaliação dos efeitos da radiação por feixe de elétrons na resistência de embalagens a Lasioderma serricorne, Plodia interpunctella e Sitophilus zeamais / Radiation effects evaluation for electrons sheaf in packages resistance in a Lasioderma serricorne, Plodia interpunctella and Sitophilus zeamais

Juliana Nazaré Alves 16 August 2011 (has links)
As pragas de produtos armazenados constituem um problema para o homem, depreciando produtos e causando prejuízos econômicos. Dentre estas pragas temos o Lasioderma serricorne (F. 1792), Sitophilus zeamais (M. 1855) e Plodia interpunctella (H. 1813) conhecidos por infestar produtos armazenados como: grãos, farelos, farinhas, café, fumo, frutas secas e especiarias. Essas pragas perfuram e adentram as embalagens, ovipositando sobre o substrato. Neste contexto a embalagem desempenha um papel fundamental, impedindo o contato e proliferação de pragas no produto acondicionado. Assim, para proteger o produto acondicionado e prolongar a sua vidaútil a embalagem deve apresentar boa resistência mecânica à tração e à perfuração, boa selabilidade, boas propriedades de barreira e não transferir odores nem sabores estranhos ao produto acondicionado. A radiação ionizante pode causar mudanças estruturais nos materiais poliméricos de embalagens, essas mudanças são causadas pelos processos de cisão e reticulação das cadeias poliméricas. Estes são processos concorrentes e a predominância de um sobre o outro depende da estrutura química do polímero, das condições da irradiação e de fatores específicos do material que irá absorver a energia. Este trabalho teve o objetivo de avaliar as mudanças nas propriedades mecânicas de estruturas de embalagem utilizadas para armazenar granola, barra de cereais e macarrão, bem como suas resistências a perfuração por L. serricorne, P. interpunctella e S. zeamais, quando submetidas a radiação por feixe de elétrons. Na metodologia foram utilizadas cinco estruturas de embalagem comercialmente utilizadas para armazenar granola, barra de cereais e macarrão compostas por (Polipropileno bi-orientado metalizado/Polipropileno bi-orientado coextrusado - BOPPmet/BOPP 50 &mu;m), (Polipropileno bi-orientado/Polipropileno - BOPP/PP 50 &mu;m), Poli(tereftalato de etileno) metalizado/Polipropileno bi-orientado coextrusado - PETmet/BOPP 32 &mu;m), Poli(tereftalato de etileno)/Polipropileno - PET/PP1 72 &mu;m) e Poli(tereftalato de etileno)/Polipropileno - PET/PP2 32 &mu;m). As estruturas de embalagens foram submetidas à doses de radiação entre 0, 10, 20 e 60 kGy, em um acelerador de elétrons de 1,5 MeV, 25 mA e 37,5 kW, à taxa de dose de 11,22 kGy/s, temperatura ambiente e presença de ar. Oito dias, 2 meses e 6 meses após as irradiações foram realizados ensaios mecânicos de resistência a tração e elongação na ruptura, resistência da selagem e resistência à perfuração, todos com base nas suas respectivas normas ASTM [35]. Os ensaios de perfuração por insetos foram realizados em sala climatizada, onde amostras irradiadas nas doses de 0, 10, 20 e 60 kGy foram seladas contendo 40 g de granola, 40 g de macarrão e barra de cereais em número de nove por ensaio, e divididas igualmente em três caixas plásticas teladas por dose estudada. Em cada caixa foram adicionados 20 adultos de cada inseto em por 60 dias, quando as embalagens foram avaliadas para verificação de possíveis perfurações. As diferenças entre os resultados das amostras foram estatisticamente avaliados pelo método ANOVA (p<0,05). Os resultados mostraram que quanto à resistência a perfuração por L. serricorne, P. interpunctella e S. zeamais as estruturas poliméricas avaliadas apresentaram baixa resistência à perfuração por insetos antes e após o tratamento. BOPPmet/BOPP (50 &mu;m), PETmet/BOPP (32 &mu;m), PET/PP1 (72 &mu;m) e PET/PP2 (32 &mu;m) apresentaram perdas significativas nas estruturas nas propriedades mecânicas estudadas. O BOPP/PP (50 &mu;m) apresentou o melhor conjunto de respostas nas propriedades mecânicas ao tratamento por radiação com feixe de elétrons em doses de até 10 kGy. Dentre as propriedades mecânicas avaliadas a selagem foi a mais afetada pela radiação ionizante, tendo apresentado, em geral, perdas crescentes com a dose de radiação. / The plagues of stored products consist of a man problem, depreciating products and causing economical damages. Among these curses we have Lasioderma serricorne (F. 1792), Sitophilus zeamais (M. 1855) and Plodia interpunctella (H. 1813) known by infesting stored products as: grains, brans, flours, coffee, tobacco, dried fruits and spices. These curses perforate and penetrate the packages, ovipositing over the substratum. In this context the package plays a fundamental part, preventing the contact and curses proliferation in the packed product. So, to protect the packed product and to prolong its shelf life, the package should have good mechanical resistance to tension and perforation, good sealing, good barrier properties and should not transfer odors nor strange flavors to the packed product. The ionizing radiation can cause structural changes in polymer packages, these changes are caused by the scission processes and reticulation of the polymers chains. These are concurrent processes and the predominance of one over the other depends on the chemical structure of the polymer, the irradiation conditions and specific factors of the material that will absorb the energy. This work had the objective to evaluate the changes in mechanical properties of package structures used to store granola, cereal bar and pasta, as well as its resistance to perforation by L. serricorne, P. interpunctella and S. zeamais, when submitted to electrons sheaf radiation. In this methodology were used five structures of commercially utilized packages to store granola, cereal bar and pasta composed by (Polypropylene bi-oriented metallic/Polypropylene bi-oriented coextruded - BOPPmet/BOPP 50 &mu;m), (Polypropylene bi-oriented/Polypropylene - BOPP/PP 50 &mu;m), Poli (ethylene terephthalate) metallic/Polypropylene bi-oriented coextruded - PETmet/BOPP 32 &mu;m), Poli (ethylene terephthalate) /Polypropylene - PET/PP1 72 &mu;m), Poli (ethylene terephthalate)/Polypropylene - PET/PP2 32 &mu;m). The structures of packaging were submitted to radiation doses between 0, 10, 20 and 60 kGy, in one electron accelerator of 1,5 M and V, 25 mA and 37,5 kW, dose tax of 11,22 kGy / s, room temperature and air presence . Eight days, Two and Six months after irradiations, mechanical resistance experiment were accomplished to tension and elongating in rupture, sealing resistance and perforation resistance, all based in respective ASTM norms. The perforation experiment by insects were realized in an acclimatized room, where irradiated samples in doses of 0, 10, 20 and 60 kGy were sealed containing 40 g of granola, 40 g of pasta and cereal bar in number of nine by experiment, and equally divided in three plastic screened boxes by studied dose. In each box 20 adults of each insect were added in for 60 days, when the packages were evaluated to verify possible perforations. The differences between the sample results were statistically evaluated by ANOVA (p<0.05). The results showed that concerning the perforation resistance by L. serricorne, P. interpunctella and S. zeamais the polymeric structures evaluated showed low resistance by insects perforation before and after the treatment. BOPPmet/BOPP (50 &mu;m), PETmet/BOPP (32 &mu;m), PET/PP1 (72 &mu;m) and PET/PP2 (32 &mu;m) structures showed significant losses in mechanical properties studied. The BOPP/PP (50 &mu;m) showed the best set of answers in mechanical properties to the radiation treatment with electrons sheaf up to 10 kGy doses. Among the mechanical properties evaluated, sealing was the most affected by ionizing radiation, has shown, in general, increasing losses with radiation dose.

Page generated in 0.073 seconds