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Green plastics are constantly being used to minimize the negative impacts of the polymers made of fossil fuels such as petroleum. Non-renewable petroleum-based products are employed in wide range of human activities, yet plastic waste accumulation represents a serious issue for the environment (Mohd Rafee et al., 2019). On the other hand, the use of natural fibres in composite materials, such as sisal fibres, in substitution for synthetic fibres, has increased considerably. The aim of this study was to develop a low-cost manufacturing process of composites with reuse of polyethylene bags made of sugarcane ethanol (green polyethylene) reinforced with sisal fibres. The hot compression moulding (185 °C) was used to mould composite structural board. Tensile tests were conducted to evaluate the influence of the reinforcement configuration on the mechanical properties of the composites, considering two arrangements: woven fibres in (0°/90°) and randomly arranged. The results indicated that the use of woven sisal fibres in (0°/90°) as reinforcement of the green HDPE showed an increase in the tensile strength (33.30%) in contrast to the pure traditional HDPE. Randomly arranged sisal fibre-reinforced green HDPE composites showed higher modulus of elasticity than pure traditional HDPE (76.83%). Composites with woven sisal fibres showed higher values for tensile strength and ultimate strain, and lower modulus of elasticity than composites with randomly arranged sisal fibres. In addition, failure modes of the composites were observed. The results showed the viability of producing these composites by the developed equipment and the potential use of these materials as structural components.

This work evaluates a new eco-friendly surface treatment method for coir fibres based on sodium bicarbonate (NaHCO3). The fibres are treated with 10 wt% NaHCO3 solution for different periods of time (24, 96 and 168 h). A 2141 Full Factorial Design is established to investigate the effect of the type of matrix (epoxy and polyester) and treatment time (24, 96 and 168 h) on the mechanical properties of coir fibre composites. X-Ray diffraction (XRD) analysis reveals that the treatment does not promote a complete change of cellulose-I into cellulose-II. However, the degradation of hemicellulose and pectin of the fibre surface is evidenced by the thermogravimetric (TGA) curves. The chemical treatment contributes to increase the fibre density and to reduce its thermal stability. Single fibre tensile tests reveal a gradual increase in the elastic modulus attributed to the treatment time factor. Epoxy composites presented higher tensile and flexural strength in comparison to polyester composites, which exhibit higher tensile and flexural modulus. The alkaline treatment does not affect the mechanical strength of the composites. However, higher tensile and flexural moduli are obtained when the treatment time increases to 96 or 168 h. The proposed treatment proves to be feasible and efficient to increase the stiffness of coir fibre composites, besides being less damaging to the environment after disposal when compared to strongly alkaline solutions such as NaOH.

In recent years, green composites based on thermoplastic matrices from renewable sources, and reinforced with natural fibres, have gained significant importance in different industrial applications, due to lower environmental impacts and production costs than traditional composites. This work investigates the manufacturing process, fibre/matrix integration and mechanical properties of a novel environmentally friendly green composite with a recyclable biobased polymer from a renewable source and a biodegradable natural fibre. Untreated woven sisal fibres reinforced post-consumer green polyethylene composites were evaluated in terms of flexural, tensile and impact properties. Traditional and green high-density polyethylene (HDPE), originated from sugarcane ethanol, were utilised as matrices of the investigated composites. Woven sisal fibres were arranged in two different stacking sequences, i.e. [0°/90°] and [± 45°], being incorporated into the HDPE with a mass percentage proportion of 30/70 (fibre/matrix). A low-cost manufacturing process based on the hot compression moulding was used to produce the composites. The results were analysed by a factorial design to identify the effects of polyethylene type and the use of woven sisal fibres, considering the [0°/90°] and [± 45°] orientations. Thermal gravimetric analysis was used to verify the thermal stability of the sisal fibre. The topographic surface of sisal fibres was observed by scanning electron microscopy. The results showed that the use of green polyethylene reinforced with untreated woven sisal fibres achieved higher flexural modulus (35%), flexural strength (13%), tensile strength (39%) and ultimate strain (68%) than traditional polyethylene without reinforcement. The green composite presented promising mechanical results to replace materials from non-renewable sources and can reduce manufacturing costs of the final product. These composite materials can be efficient for structural applications such as insulated panels, drywall and partitions for furniture.

The cutting fluids contributed for removing chips, cooling, and lubricating, on the other hand, are harmful to the environment. The minimum quantity lubrication technique (MQL) in machining operations proved to be suitable in addition to minimizing the environmental impact. The present work is focused on the drilling of electrolytic copper using biodegradable oil as cutting fluids applied by the MQL technique. The specific cutting pressure, burr height, and maximum diameter were measured varying the cutting parameters, cutting speed, feed, and lubrication condition (dry, flooded, and MQL). A statistical analysis was utilized to determine the influence of cutting parameters in the variables measured. The results indicated that the second-order interactions have a significant influence on the specific cutting pressure and in burr height. The lowest burr height was obtained using flood and MQL. The MQL system demonstrated the lowest specific cutting pressure, while the flood exhibited the best performance for diameter analysis. In addition to this, it can be confirmed that the MQL technique may replace the flooding drilling (abundant flow), minimizing the environmental impact.

A full factorial design (2 231 ) has been used to investigate the effect of the use of sodium hydroxide fibre treatment, Portland cement and uniaxial pressure on the physical and mechanical properties of hybrid short coir fibre reinforced composites (HSCoirFRCs). The response variables considered in this work were the apparent density, porosity, tensile and flexural strength , the modulus of elasticity and the Charpy impact resistance. The alkali treatment contributed not only to reduce the apparent porosity , but also to increase the mechanical properties of the HSCoirFRCs. A reduction of the impact resistance and an increase of the apparent density was also identified after treatment. Cold pressing significantly affected the physical and mechanical properties of the HSCoirFRCs. Higher pressure levels enhanced the wettability of the fibres and, consequently, the mechanical performance of the composites. The incorporation of cement microparticles as a second reinforcement phase was however not effective, leading to decreased strength and an increased apparent density of the materials. The HSCoirFRC structure can be considered an economical and sustainable alternative for future secondary structural parts in lightweight transport applications.

Over the last few decades, a significant amount of research has been focused on the use of natural fibres as reinforcement in polymers, due to their intrinsic properties such as sustainability, easy availability and processing, biodegradability and moderate mechanical strength. Among natural fibres, coir is a low-cost fibre extracted from coconut palm which is extensively produced in Brazil. A full factorial design was carried out to investigate the effects of the manufacturing and composition parameters on the mechanical and physical properties of short coir fibre–reinforced composites (SCoirFRCs). The random short fibres were mixed with epoxy polymer and compacted by uniaxial pressure. The physical and mechanical responses, namely, apparent density, impact resistance, flexural strength and modulus, were investigated under a design of experiment approach. SCoirFRCs fabricated with 35% of fibre volume fraction, 375 g/m2 of fibre grammage and HY956 epoxy hardener type achieved higher flexural modulus and impact resistance, while those consisting of 30 vol% of coir fibres, HY956 type and 300 g/m2 of grammage revealed higher flexural strength. The findings revealed that the mechanical properties of SCoirFRCs are substantially dominated by the properties of the matrix phase and fibre wettability.

The hybrid configuration of bio-reinforced composites has established a new extended boundary for the development of pro-ecological technologies due to light weight, moderate specific strength, low cost, environmental benefits, and potential applications of natural components. This work investigates the physical and mechanical properties of hybrid composites made of sisal/glass fibres and Portland cement inclusions. A full factorial design was generated to identify the effects of the stacking sequence and cement particles on the flexural strength, flexural stiffness, apparent density, apparent porosity and water absorption of the composites. The significant contributions of these main factors and their interactions were determined via Design of Experiments (DoE) and Analysis of Variance (ANOVA). The fracture features and damage mechanisms of hybrid composite were also reported. The inclusion of cement microparticles led to an increased apparent porosity, as well as enhanced water absorption, flexural stiffness and flexural strength of the hybrid composites. The mechanical properties were strongly dependent on the fibre stacking sequence, which accounts for approximately 98% of the effects observed. Moreover, the stacking sequence affected the damage mechanism of the bio-composites. Finally, the replacement of glass fibres by unidirectional sisal reinforcements may potentially improve the specific properties in structural applications with an environmental sustainable footprint.

Rapid prototyping for material deposition or additive manufacturing has been widely used for short time production of parts with complex geometry in small series. The three-dimensional printing process needs post-processing to improve the strength, stiffness and/or surface finish of the parts. Printed parts in pristine condition are generally very brittle with a porous structure, so infiltrates have been introduced to improve their mechanical and physical characteristics. This work investigates the effect of two infiltrates, epoxy polymer and cyanoacrylate, under a vacuum pressure system on the mechanical properties of powder-based composites made by three-dimensional printing. Samples printed under pristine and infiltrated conditions were tested under tensile, flexural, compressive and impact loadings. The infiltrated samples achieved superior mechanical properties, especially when the epoxy polymer was applied via a vacuum system. The microstructural analysis showed that the infiltrates were not able to penetrate the entire sample, revealing a porous structure in the centre, mainly when the cyanoacrylate was used. The epoxy polymer infiltrate was able to substantially increase the mechanical performance of three-dimensional samples, being a promising material when higher structural requirements are required.

This work investigates the effect of silica nanoparticles functionalized with poly-diallyldimethylammonium chloride (PDDA) and silica microparticle inclusions (1.0 wt% and 3.5 wt%) on the impact resistance of hybrid carbon fibre reinforced composite laminates (HCFRCs) and tensile modulus of particle reinforced polymers (PRPs) via Full-Factorial Design of Experiments. The data were analysed with Analysis of Variance (ANOVA). The inclusion of particles led to reduced impact absorption of HCFRCs, except for composites with 1.0 wt% of silica in microscale, which provides an increase of 11.75% in the impact resistance. Microstructural analysis of fractured impact samples revealed pull-out as the predominant fracture mode in 1.0 wt% silica microparticle composites. Such mechanism leads to impact energy dissipation which may explain the increased impact resistance of these samples.

Surface modification induced by sodium carbonate on coir fibres was studied in view of its application as a reinforcing agent in polyester and epoxy polymer fibre-reinforced composites. Coir fibres were treated with a 10 wt% sodium carbonate solution for different periods of time (24, 96 and 168 h) at room temperature. The surface treatment was evaluated by scanning electron microscopy, X-ray diffraction and thermogravimetric analysis. Tensile, flexural and impact properties of treated and untreated coir fibre-reinforced composites were compared. Coir-reinforced epoxy and polyester composites were manufactured by the uniform dispersion of randomly oriented coir fibres within the polymeric matrix. Tensile and flexural modulus of coir-reinforced polyester composites increased nearly 28% and 25%, respectively after 96 h of coir treatment. An analogous increase of 31% and 17% was obtained for coir-reinforced epoxy composites. In addition, coir-polyester composites achieved superior tensile (∼17%) and flexural (∼5%) modulus and impact strength (∼193%) compared with coir-epoxy-derived composites. In contrast, coir-epoxy composites led to superior tensile and flexural strength. The experimental results revealed that sodium carbonate solution effectively removes hemicellulosic compounds, promotes swelling and increases superficial roughness of the fibres, improving the mechanical properties (modulus and strength) of the coir-reinforced composites studied.

Applications for composite materials are constantly increasing because of their lightweight combined with a high modulus of elasticity. Thus, the drilling of such materials is cause for concern for the scientific community since these components need generally to be fixed and assembled. Dimensional variations and the presence of burr are some of the problems that commonly arise due to the drill action in the composite material. Such problems should be minimized because it can compromise the quality of the final product. The present work studies the drilling of a sandwich composite material consisting of aluminium and polyethylene core (PEALL). The drilling tests were carried out using a TiO2-coated high-speed steel drills (HSS drills) deposited by sol–gel process. In order to optimize the hole quality, the influences of the TiO2 coating and the drilling parameters (speed and feed) are analysed. The thrust force, burr height and maximum diameter are collected to statistical study (analysis of variance (ANOVA)). The results underline that the TiO2-coated tool exhibits the best performance and improves the hole quality. Thus, the sol–gel method is a promising technique to coat the complex geometries of the HSS tools.

Cementitious composites are low cost and readily manufactured materials which can be used for specialist applications such as the production of aerostatic porous bearings. A design of experiment was used to identify the effects of superplasticizer additions and carbon nanotube inclusions on the physical and mechanical properties of cementitious composites which can be applied as porous restrictor in aerostatic thrust bearings. The presence of carbon nanotubes was able to increase the bulk density, the compressive strength and the modulus of elasticity, and also decrease the apparent porosity of the composites. The composite made with 0.4 wt.% of superplasticizer and 0.05 wt.% of carbon nanotubes achieved acceptable properties for the use as double-layered porous restrictor in aerostatic thrust bearings.

Over the years, with the increasing development of engineering materials, the emergence of new composites, fiber metal laminated, biomaterials, metal alloys etc., and with demand for products less expensive, less polluting and more efficient, the manufacturing engineering also needs to develop to be able to process these new materials. Materials and tool geometries, intelligent mechanisms, modular machines, also follow this setting. To that end, this work comes to raise the main parameters that influence in the hole quality surface of finished product. Were used two polymeric materials, ultra high molecular weight polyethylene (UHMW-PE) and polytetrafluoroethylene (PTFE), two feed rates, three rotations and three tool geometries, allowing to identify which of these parameters have greater influence on the thrust force and the characteristics of the finished product and dimensional deviation.

This work investigates the effect of using functionalised poly-diallyldimethylammonium chloride (PDDA) silica micro and nanoparticles on the apparent density, tensile and flexural strength and modulus of hybrid glass fibre reinforced composites. The work is carried out using a Design of Experiment (DoE) approach on a population of 60 composite specimens produced according the size of the nanoparticles and their weight fraction. A 2% of weight fraction of functionalised silica nanoparticles is shown to reduce the flexural strength and density of the composites, but to maximise significantly both the tensile, flexural modulus and tensile strength of the hybrid glass fibre materials.

Fibre metal laminates (FMLs) have been widely used to manufacture airframe components. This work describes novel sisal fibre reinforced aluminium laminates (SiRALs) that have been prepared by cold pressing techniques and tested under tensile, flexural and impact loading. The pristine sisal fabric and the sisal fibre reinforced composites (SFRCs) were also tested to understand the difference in mechanical performance of the sisal fibre metal laminates. The SiRALs achieved not only the highest modulus and strength, but also the highest specific properties. The mean specific tensile strength and modulus of the SIRALs reached increases of 132% and 267%, respectively, when compared to the sisal fibre reinforced composites (SFRCs). Moreover, the mean specific flexural strength and modulus of the SiRALs were significantly higher than SFRCs, revealing increases of 430% and 973%, respectively. A delamination fracture mode was noted for SiRALs under bending testing. The SiRALs can be considered promising and sustainable composite materials for structural and multifunctional applications.

The development of new materials based on industrial wastes has been the focus of much research for a sustainable world. The growing demand for tyres has been every year exacerbating environmental problems due to indiscriminate disposal in the nature, making a potentially harmful waste to public health. The incorporation of rubber particles from scrap tyres into polymeric composites has achieved high toughness and moderate mechanical properties. This work investigates the geometric effects (thickness, width and internal cell angle) of auxetic structures made of recycled rubber composites based on experimental and numerical data. The response surface models integrated with the swarm intelligence and finite element analysis were proposed in order to obtain a range of solutions that provides useful information to the user during the selection of geometric parameters for reentrant cells. The results revealed the cell thickness ranges from 39-40 mm and 5.98-6 mm, and the cell angle range from -0.01 to -0.06º maximize the ultimate strength. The same parameters were able to optimize the modulus of elasticity of rubber auxetic structures, excepting for the angle factor which must be set between -30º and 27.7º. The optimal Poisson's ratio was found when the cell angle ranged from -30º to -28.5º, cell width ranged from 5-5.6 mm and 2 mm in thickness.

Composite materials are widely employed in the naval, aerospace and transportation industries owing to the combination of being lightweight and having a high modulus of elasticity, strength and stiffness. Drilling is an operation generally used in composite materials to assemble the final product. Damages such as the burr at the drill entrance and exit, geometric deviations and delamination are typically found in composites subjected to drilling. Drills with special geometries and pilot holes are alternatives used to improve hole quality as well as to increase tool life. The present study is focused on the drilling of a sandwich composite material (two external aluminum plates bound to a polyethylene core). In order to minimize thrust force and burr height, the influence of drill geometry, the pilot hole and the cutting parameters was assessed. Thrust force and burr height values were collected and used to perform an analysis of variance. The results indicated that the tool and the cutting speed were the parameters with more weight on the thrust force and for burr height they were the tool and the interaction between tool and feed. The results indicated that drilling with a pilot hole of O4 mm exhibited the best performance with regard to thrust force but facilitated plastic deformation, thus leading to the elevation of burr height, while the lowest burr height was obtained using the Brad and Spur drill geometry.

Timber is the oldest construction materials in the world, have been widely used in structures in addition to having a high longevity, if treated properly (maintenance). If this does not occur, the wood deteriorates due to the action of insects, fungi and other aggressive agents. There are several materials and techniques used to reinforce the damaged parts. This paper presents an experimental study ofEucalyptus grandis and Pinus elliiottiitimber beams rein forced with sisal fibres laminated composite materials. The co mposite material and the wood were prepared for testing. In order to simulate the defect, some parts were cracked. The study was to determine the maximu m load (rupture) applied on the timberin the conditions: without defect, with defect and without composite and with defect and with composite, aiming to verify the efficiency of the laminate as reinforcement in the wooden beams. The experimental results indicate the possible use of the laminated composite as reinforcement, presenting considerable increase in the maximu m strength supported by the timber when compared to unreinforced cracked condition, being more efficient for the Pinus elliiottii species.

In today's modern world the composite materials have been widely used not only for aerospace/aeronautics, but also automotive, sports and construction industries. The flexural strength of laminated composites depends on the characteristics of dispersive and matrix phases, considering the presence of tensile and co mpressive loadings. For this reason, the addition of particles into the matrix phase has been investigated to enhance its stiffness and consequently the elastic modulus of the composite. Th is work investigates a glassfibre co mposite reinforced with silicon carbide part icles. The following responses were evaluated: apparent density, water absorption, flexural strength, modulus of elasticity. The results were compared to those manufactured with no silicon carbide particles. It was observed that the silicon carbide particles provided the increase of the apparent density and flexu ral strength of the composites.

CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior O desenvolvimento de materiais compósitos sustentáveis, a partir de materiais poliméricos reciclados e resíduos da indústria da madeira e processamento de rochas, permite reduzir o volume desses subprodutos, minimizando os impactos na saúde e no meio ambiente. Atualmente, o polipropileno (PP) é o polímero mais reciclado da indústria, enquanto a indústria madeireira tem utilizado cada vez mais madeira de plantios florestais sustentáveis como eucalipto. Hoje, o Brasil é um dos maiores exportadores mundiais de placas de granito que exigem corte, modelagem e acabamento de lâminas de rocha ornamental e de construção. O rejeito de pó da indústria de extração e beneficiamento de rochas ornamentais é comumente descartado no meio ambiente sem tratamento prévio. Assim, a opção tecnológica pelo desenvolvimento de materiais compósitos apresenta-se como uma alternativa sustentável para as indústrias de transformação e fabricação, possibilitando o desenvolvimento de novos materiais com características técnicas especiais. Compósitos constituídos de fibras e partículas têm sido o foco de pesquisas recentes a fim de otimizar as propriedades físico-mecânicas desses materiais. Nesta tese, compósitos híbridos foram preparados a partir da combinação de microfibras de eucalipto não tratadas, alcalinizadas e branqueadas com partículas de granito, respectivamente, como reforços em matriz de polipropileno reciclado (PPr). A matriz termoplástica foi caracterizada por calorimetria exploratória diferencial (DSC), termogravimetria (TGA), termogravimetria derivada (DTG), espectrometria no infravermelho com transformada de Fourier (FTIR) e índice de fluidez (MFI). As microfibras de eucalipto foram caracterizadas por microscopia eletrônica de varredura (MEV) e espectroscopia de energia dispersiva de raios X (EDS). Para a caracterização das partículas de granito foram utilizadas técnicas de MEV, EDS e difratometria de raios X (DRX). Os compósitos foram obtidos pelos métodos de extrusão e injeção, moldados em corpos de prova para ensaios de tração, flexão em três pontos, impacto Izod e dureza Shore D. Além disso, foi feita uma resposta de avaliação estatística por análise de variância. As seções transversais das amostras submetidas aos ensaios mecânicos foram analisadas quanto à morfologia, microestrutura e interface matriz-cargas. Também foram caracterizadas as propriedades térmicas, físico-químicas, reológicas, higroscópicas e a taxa de fusão dos compósitos. Os resultados experimentais mostraram que houve aumento nos módulos de elasticidade em tração e flexão, rigidez e redução da tenacidade sob impacto com a adição de microfibras e pó de granito em matriz. Transições de fratura dúctil-frágil foram verificadas, sendo presente fratura dúctil em tração de compósitos com microfibras de eucalipto e fratura frágil com adição de partículas finas de granito. Efeito de transcristalização de cadeias de polipropileno pode ter ocorrido na superfície de óxidos do pó de granito, provavelmente nanométricas. Retardamento na taxa de queima do polímero e menor absorção de água dos compósitos foram obtidos com a adição da fração inorgânica no sistema. As partículas de granito em pó podem ser incorporadas à matriz de polipropileno associada a microfibras de eucalipto formando compósitos híbridos, com potencial aplicação em engenharia estrutural como indústrias de transporte e construção civil. The development of sustainable composites materials, from recycled polymeric materials and waste from the wood industry and stone processing, allows reducing the volume of these by-products, minimizing impacts on health and the environment. Nowadays, polypropylene (PP) is the most recycled polymer in industry, while the furniture industry has increasingly used timber felled from sustainable forest plantations as a eucalypt. The powder tailing from the ornamental stone extraction and processing industry is commonly disposed of in the environment without previous treatment. Today, Brazil is one of the leading exporters of granite slabs worldwide which requires cutting, shaping, and finishing of ornamental and building stone blades. Thus, the technological option for the development of composite materials presents itself as a sustainable alternative for processing and manufacturing industries, enabling the development of new materials with special technical features. Composites made up of fibers and particles have been the focus of recent research in order to optimize the physical-mechanical properties of these materials. In this thesis, hybrid composites were prepared using untreated, alkalized and bleached eucalyptus microfibers with granite particles, respectively, as reinforcements in recycled polypropylene matrix (rPP). The thermoplastic matrix was characterized by differential scanning calorimetry (DSC), thermogravimetry (TGA), derivative thermogravimetry (DTG), Fourier transform infrared spectrometry (FTIR) and flow index (MFI). Eucalyptus microfibers were characterized by scanning electron microscope (SEM) and energy-dispersive X-ray spectroscopy (EDS). To characterized granite particles, SEM, EDS and X-ray diffraction (XRD) techniques were used. A single screw extruder and injection molding were used to manufacture the composites specimens. The mechanical characterization was performed through tensile, bending, Izod impact and Shore D hardness tests. Also, a statistical evaluation response by analysis of variance was made. The cross-sections of the samples submitted to mechanical tests were analyzed for morphology, microstructure and matrix-filler interface. Thermal, physicochemical, rheological, hygroscopic properties and the melting rate of the composites were also characterized. The experimental results showed an increase in the modulus of elasticity in traction and bending, stiffness and a reduction in toughness under impact with the incorporation of microfibers and granite powder in the matrix. Ductile-brittle fracture were observed, with ductile fracture present in tensile composites with eucalyptus microfibers and brittle fracture with the inclusion of fine granite particles. The effect of transcrystallization of polypropylene chains may have occurred on the surface of oxides of granite powder, probably nanometric. Delay in the polymer burning rate and lower water absorption of the composites were obtained with the addition of the inorganic fraction in the system. The results showed that powder granite particles can be incorporated into the polypropylene matrix associated with eucalyptus microfibers forming hybrid composites with potential application in structural engineering, such as transport and civil construction industries.

CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico A prótese desempenha um papel importante no processo de reabilitação, pois é um recurso tecnológico terapêutico capaz de ampliar as capacidades funcionais da pessoa com amputação. Atualmente, as oficinas ortopédicas credenciadas ao Sistema Único de Saúde (SUS) brasileiro para atender as demandas de fabricação de prótese apresentam um proceso artesanal, que gera desconforto ao paciente. Além disso, o SUS disponibiliza apenas próteses de modelo padrão dinâmicas, por tanto, não oferece ao usuário a chance de usufruir dos benefícios de uma prótese robótica. Por tanto, este trabalho tem por objetivo implementar a metodologia de projeto denominada de “Design Thinking” no desenvolvimento de uma prótese robótica de membro superior para amputação transradial, que tenha possibilidades de ser incluída na Tabela de Procedimentos, Medicamentos, Órteses, Próteses e Materiais Especiais (OPM) do Sistema Único de Saúde para que seja oferecida aos usuários. Trata-se de um estudo metodológico, com desenvolvimento de produto, por meio da Metodologia de Design Thinking. Tendo como resultado o desenvolvimento de uma prótese robótica de membro superior para amputação transradial, onde o investimento nos materiais envolvidos para sua criação foi de aproximadamente R$ 250,00, além disso, é um tipo de dispositivo que não está disponível na tabela do SUS, por se tratar de uma prótese ativa que possui componentes eletrônicos e mecânicos que realizam o movimento de preensão palmar, com capacidade de carga de 3,7 kg nos dedos e tempo de resposta de 0,5 s. Com isso, foi demonstrado que com a implementação da metodologia de Design Thinking foi possível desenvolver um modelo de prótese para amputação transradial com potencial para ser incluída na tabela do SUS, demonstrando a viabilidade de execução do processo automatizado. Prosthesis plays an important role in a rehabilitation process, as it is a therapeutic technological resource capable of expanding the functional capabilities of the person with amputation. However, the orthopedic workshops accredited to the Brazilian Unified Health System (SUS) to meet the demands of prosthesis manufacturing have a handmade process, which causes discomfort to the patient. In addition, the SUS only provides prostheses with dynamic standard models, not offering the user the chance to enjoy the benefits of a robotic prosthesis. Therefore, the purpose of this study was to implement the Design Thinking methodology developing an upper limb robotic prosthesis for individuals with transradial amputation, with the potential to be included in the Table of Procedures, Drugs, Orthoses, Prostheses and Materials (OPM) of the SUS to be offered to users. This is a methodological study, with product development, through the Design Thinking Methodology. A robotic prosthesis of the upper limb was developed for individuals with low-cost transradial amputation, where the investment in the materials involved for its creation was approximately R$ 250.00. The prosthesis developed is an active prosthesis is not available in the SUS table, which perform the handgrip movement, with a load capacity of 3.7 kg on the fingers and 0.5 s response time. With this, it was demonstrated that with the implementation of the Design Thinking methodology made possible the development of an upper limb robotic prosthesis with the potential to be included in the SUS table, allowing them to take advantage of this type of technology.

CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior Alguns polímeros naturais estão sendo bastante visados por serem capazes de formar filmes plásticos biodegradáveis. Entretanto, esses materiais são, normalmente, menos resistentes do que os polímeros convencionais, principalmente porque podem absorver muita água do ambiente. Com a intenção de contornar esse problema, neste trabalho, foi proposta a preparação de filmes poliméricos a partir da combinação de dois polímeros biodegradáveis, sendo eles alginato ou xantana e carboximetilcelulose (CMC). Para a mistura de ambos, utilizou-se apenas a mudança de pH (meio neutro, pH próximo de 7, para a mistura de alginato e CMC; e o meio básico, pH próximo de 13, para as misturas de alginato ou xantana e CMC). Os resultados obtidos foram divididos em três seções, sendo a primeira focada nas amostras preparadas em meio básico e a segunda e a terceira para os filmes preparados em meio neutro. Assim, na primeira seção, foram avaliadas as propriedades físicas e químicas dos filmes formados. Na segunda, foi preparado um compósito com nanocristais de celulose. A terceira seção consistiu na reticulação, a partir da combinação de íons cálcio e ferro ou da utilização de epicloridrina e na utilização de uma cobertura hidrofóbica sobre os filmes, a fim de controlar e reduzir a taxa de intumescimento e a liberação de substâncias. Para os filmes preparados em meio básico, os resultados indicaram que eles apresentaram a menor taxa de transmissão e permeação do vapor de água e, consequentemente, a partir de uma análise qualitativa, tiveram o melhor desempenho na proteção contra o amadurecimento das frutas. O filme de alginato e CMC preparado em meio neutro apresentou a maior taxa de transmissão de vapor e o maior controle do intumescimento. O nanocompósito apresentou o maior módulo de elasticidade, mas não reduziu a taxa de absorção de líquido do material. Após a reticulação desses filmes, foi observada a redução da taxa de intumescimento e o aumento do tempo de degradação. Vale destacar que a combinação da adição dos nanocristais com a reticulação iônica na blenda de alginato e carboximetilcelulose apresentou-se como potencial substituto para a epicloridrina, um reagente considerado tóxico. Assim, com este trabalho, foi possível obter filmes poliméricos de baixo custo de produção, que apresentaram módulo de elasticidade equiparável aos polímeros convencionais, e que poderiam ser capazes de atuar como embalagens ou liberar substâncias no meio em que são colocados. Natural polymers are being targeted for forming biodegradable plastic films. However, these materials are usually less resistant than conventional polymers, mainly because they can absorb a lot of water from the environment. In order to minimize this problem, it was proposed to prepare polymeric films from the combination of two natural polymers based on alginate or xanthan and carboxymethylcellulose (CMC). For the mixture of the polymers, only the pH change was used (with the neutral medium, pH close to 7, for the mixture of alginate and CMC and the basic medium, pH close to 13, for mixtures of alginate or xanthan and CMC). The results obtained were divided into three sections, the first one focused on samples prepared in a basic medium, and the second and the third focused on films prepared in a neutral medium. Thus, in the first section, the physical and chemical properties of the formed films were evaluated. In the second, a composite with cellulose nanocrystals was prepared. And the third section consisted of make crosslinking, from the combination of calcium and iron ions or the use of epichlorohydrin or the use of a hydrophobic coating on films, in order to control and reduce the rate of swelling and evaluate the release of substances. The results obtained indicated that the films prepared in a basic medium showed a lower rate of transmission and permeation of water vapor and, consequently, from qualitative analysis, they were more effective in protecting against fruit ripening. The film prepared in a neutral medium had the highest rate of vapor transmission and the least rate of swelling. Its nanocomposite had the highest modulus of elasticity, but it did not reduce the rate of swelling of the material. The cross-linking test contributed to the reduction of the swelling rate and to the increase of the degradation time. It is worth noting that the combination of the addition of nanocrystals with crosslinking from metal ions in alginate and CMC films was presented as a potential substitute for epichlorohydrin, a reagent considered toxic. Thus, from this study, it was possible to obtain polymeric films of low production cost, which presented a modulus of elasticity comparable to conventional polymers, and which may be able to act as food packaging or release substances in the environment in which they will be placed.

FAPEMIG - Fundação de Amparo à Pesquisa do Estado de Minas Gerais A Manufatura Aditiva (MA) atualmente possui várias aplicações na área da saúde, como a construção de biomodelos para apoio em cirurgias, à adaptação de produtos na área médica e a construção de ferramentais para fabricação de próteses e órteses. Nesse contexto foi realizada a aplicação de digitalização tridimensional (3D) e MA no desenvolvimento de Ferramental Rápido (FR) para fabricação de prótese maxilofacial. Para isso foi realizada a digitalização 3D e a aquisição da forma geométrica do paciente e da prótese, e a partir desses dados foi elaborado um modelo 3D do molde para obtenção da prótese facial. O modelo 3D foi exportado em arquivo com extensão STL (Stereolithography) e utilizando um software foi fatiado em camadas e impresso por meio da tecnologia de jateamento de aglutinante que necessita de pós processamento com material infiltrante para melhoria da resistência mecânica do molde. Este material infiltrante também deve permitir a polimerização do elastômero maxilofacial MDX4-4210. Ao total foram testados seis grupos de revestimento em corpos de prova, e o revestimento com cianocrilato com a adição de uma camada de verniz vitral apresentou-se como a melhor opção para a confecção de moldes (muflas) após testes mecânicos. O processo foi aplicado em um caso clínico de confecção de prótese facial e obteve sucesso. Pode-se concluir que viabilidade da utilização de FR na produção de prótese maxilofacial, e também melhoria do formato da prótese facial, da espessura da borda e adaptação ao paciente, quando comparada ao processo de confecção convencional. Additive Manufacturing (AM) currently has several applications in healthcare, such as the construction of biomodels to support surgeries, the adaptation of medical products and the construction of tools for the manufacture of prostheses and orthoses. In this context, we propose the application of three-dimensional (3D) and AM scanning in the development of Rapid Tooling (RT) for manufacturing maxillofacial prostheses. The 3D digitization allows the acquisition of the geometric shape of the patient and the prosthesis and from this data is made a 3D model of the mold to obtain the prosthesis. The 3D model is exported in STL (Stereolithography) format and using software is sliced and printed using binder blasting technology which requires post processing with infiltrating material to improve the mechanical strength of the mold. This infiltrating material should also allow the polymerization of MDX4-4210 maxillofacial elastomer silicone. In total, six coating groups were tested and it was concluded that cyanocrilate coating with the addition of a stained glass varnish layer was the best option for mold making. The process was successfully applied in a clinical case, and it is concluded that the use of RF in the production of maxillofacial prosthesis is not only feasible, but its use has improved prosthesis shape, edge thickness and patient adaptation when compared to the prostheses produced in the conventional process.