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This work compares the influence of different thermoplastic polymer/wood powder ratios on mechanical and thermal properties of composite materials. Moreover, the effect of a coupling agent incorporation, to promote the adhesion between both components, on these properties was evaluated. The composite materials were obtained by compression moulding process and the mechanical and thermal tests were subsequently performed., “The authors gratefully acknowledge to project Fibrenamics Green - Platform for the development of innovative waste-based products, code NORTE-46-2015-03, which is co-financed by the European Union, through the European Regional Development Fund (ERDF) under the NORTE 2020 - North Portugal Regional Operational Program 2014–2020.”, info:eu-repo/semantics/publishedVersion

This paper presents a brief review on the main surface treatments that can be applied to natural fibrous materials. The various studies discussed in this paper are mainly focused on combining these materials with polymeric materials, allowing better compatibility between both, for the development of composite materials., The authors gratefully acknowledge the funding by P2020, under the Individual Project SI I&DT nº10977, entitled as “FibreInSurface – Fiber inclusion in plastic materials for automotive interior surfaces”., info:eu-repo/semantics/publishedVersion

This work compares the effect of different types of surface treatments of natural fibrous materials, particularly flax, on mechanical properties of thermoplastic polymer composites for application in automotive sector. The application of surface treatments on fibrous materials can improve the compatibility with polymeric materials. Different surface treatments were applied, namely: cleaning (L); alkali (A); coupling of different functional groups, such as benzoyl (B), amino (SA), epoxy (SE); corona (C). After the application of surface treatments, the fibrous materials were combined with polymeric materials, particularly TPO (thermoplastic polyolefin), by compression moulding. The mechanical tests were performed to evaluate the influence of different surface treatments of flax fabrics on the mechanical properties of TPO combined with these fibrous materials., The authors gratefully acknowledge the funding by P2020, under the Individual Project SI I&DT nº10977, entitled as “FibreInSurface – Fiber inclusion in plastic materials for automotive interior surfaces”., info:eu-repo/semantics/publishedVersion

This paper presents an overview of advanced auxetic fibrous architectures produced from natural fibres. Different types of structures, their production techniques, properties and current as well as future applications are discussed. Challenges for widespread applications of these advanced materials in various industrial sectors are also discussed., Portuguese National Funding, through FCT - Fundação para a Ciência e a Tecnologia, through the project grant, PTDC/CTM-POL/5814/2014., info:eu-repo/semantics/publishedVersion

In this work, mechanical performance of microcrystalline cellulose (MCC) reinforced cementitious composites has been studied. For this purpose, homogeneous suspensions of MCC (1- 5 wt. %) in water were prepared using ultrasonication energy and subsequently, the suspensions were added to cement/sand mixture to fabricate cementitious composites. The composite samples, after hydration of 28 days, were characterized for flexural and compressive properties. It was observed that both flexural and compressive strength of cement mortar improved strongly with MCC addition. The highest improvements of flexural and compressive strengths (19.2% and 51.4%, respectively) were achieved with MCC loading up to 1 wt.% and the property improvements reduced at higher MCC loadings due to MCC agglomeration. Considerable improvement in the flexural modulus of cement mortar was also achieved due to MCC addition., info:eu-repo/semantics/publishedVersion

uncorrected proof, Nowadays, the use of plant fibers in the civil construction industry is growing rapidly due to their low cost, light weight and good specific mechanical properties, lower health hazard, and environmental benefits. Nanodimensional fibers derived from plants such as nanocellulose are also getting considerable attention due to their excellent mechanical properties. This chapter discusses these different types of plant fibers and their derivatives which have huge application potential in the civil construction sector. The influence of plant fibers on microstructure as well as on physical–mechanical properties of cementitious composites are discussed in detail. The challenges regarding plant fiber processing and dispersion, the fiber/matrix interface, and the durability of plant fiber-cement composites are also addressed. The application of nanocellulose in polymer composites has been included in this chapter just to provide the readers sufficient background information and techniques to inspire engineered cement-based composites. Finally, the chapter concludes with the current application of plant fibers in civil construction and the future trends, (undefined), info:eu-repo/semantics/publishedVersion

This paper reports an overview of advanced auxetic fibrous structures and composites for various industrial applications. Most recent developments in the area of auxetic fibres, yarns, textile structures and composites are reviewed. Innovations in terms of materials, design and structures, processing technologies and innovative applications have been critically reviewed., This work is supported by Portuguese National Funding, through FCT - Fundação para a Ciência e a Tecnologia, through the project grant, PTDC/CTM-POL/5814/2014., info:eu-repo/semantics/publishedVersion

In the present research, cementitious composites have been developed using micro crystalline cellulose (MCC) as reinforcement and characterized for workability and mechanical performance. The MCC/cement composites were developed using homogenous aqueous suspensions of MCC. Homogenous dispersion of MCC in water was achieved by using magnetic stirring of pre-soaked MCC powder. The flow behaviour of freshly prepared mortar paste containing different loadings of MCC was characterized. It was noted that with the increase of MCC %, the flow values of resultant samples started to decrease. The effect of MCC on mechanical performance of cementitious composites was studied by performing flexural and compression tests. The samples at different hydration periods were also characterized for compressive properties to study the influence of hydration time on mechanical performance. An increase of 20.5% in flexural strength was achieved by incorporating 0.6% MCC in cement mortar after 28 days of hydration. Compressive strength also improved considerably using 0.2% MCC up to 28 days of hydration, after which less improvement was noticed, info:eu-repo/semantics/publishedVersion

Nowadays, growing concern about environment and sustainability led to development of new types of materials, which are called “environment friendly” materials. In agricultural field, the use of biodegradable agrotextiles and ecological products is increasing steadily and their performance is getting better and better so that they can be used as replacements for currently used plastic products. This paper provides a brief overview on the use of natural fibre based biodegradable structures in agricultural applications, focusing mainly mulching mats and plant growing pots. The advantages of these biodegradable structures as compared to the plastic ones have been also discussed., info:eu-repo/semantics/publishedVersion

The present work evaluated the surface, thermal, friction, drape and moisture properties of surgical cotton weaved and knitted fabric gauzes coated with chitosan nanocapsules containing essential oil of Copaifera multijuga Hayne. The result indicates that the biofunctionalized medical textiles induce low capillarity, allowing a good degree of moisture and absorption capacity of wound exudates. The gauzes coated with chitosan (CH) at the optimized mass fractions of 0.125 wt% demonstrate good thermal, friction and draping properties, thus promoting the best conditions for maintenance of the wound healing microenvironment. The knitted fabric shows the best thermal, friction and capillarity proprieties compared to weaved gauze. This gauze allows the development of a knitted biofunctionalized medical device especially designed for burn wounds treatment., Jefferson M. Souza acknowledge CAPES Foundation, Ministry of Education of Brazil, Proc. nº 8976/13-9. A. Zille acknowledges funding from FCT within the scope of the project POCI- 01-0145-FEDER-007136 and UID/CTM/00264., info:eu-repo/semantics/publishedVersion

Thermal property of the fabrics which are used in day to day activities is important one to provide comfort to human beings. The thermal properties of the textile materials depend on their thermal conductivity, thickness, density and thermal emission properties. The main objective of this research works is to analysis of the thermal properties of needle punched nonwoven fabrics manufactured from wool hybrid fibres in terms of thermal conductivity or thermal resistance. The thermal properties of the nonwoven fabrics were carried out using ALAMBETA equipment. The results show that the nonwoven fabric produced from wool/hollow polyester (50%/50%) exhibited less thermal conductivity., This work was carried out under the project No. 2014/38420 "SMART_BED - Development of multifunctional home textiles for children and youth", headed by LASA - Armando da Silva Antunes S.A. (Portugal), co-funded by the European Regional Development Funds FEDER, through COMPETE - Operational Program Competitiveness Factors., info:eu-repo/semantics/publishedVersion

In this research work, multi-scale glass fibre/epoxy composites were developed using micro crystalline cellulose (MCC). MCC was homogeneously dispersed in epoxy resin using ultrasonication energy and glass fabrics were subsequently impregnated with MCC dispersed resin to fabricate the multi-scale composites. Mechanical and dynamic mechanical behaviours of the developed composites were characterized. It was observed that the flexural strength of glass/epoxy composites increased strongly (up to 76%) through addition of only 1% MCC. Storage modulus of composites also increased significantly (up to 10%) through MCC addition. However, enhancement in mechanical and dynamic mechanical properties reduced at higher MCC loadings as a result of MCC agglomeration., This work is supported by Portuguese National Funding, through FCT - Fundação para a Ciência e a Tecnologia, on the framework of project UID/CTM/00264/2013., info:eu-repo/semantics/publishedVersion

This work has been performed to study the mechanical properties of multiscale cementitious composites developed by using microcrystalline cellulose (MCC) and multi-wall carbon nanotubes (MWCNTs) as reinforcements. The experimental work was carried out in two steps: (a) homogeneous suspensions of MCC (0.4 wt.% and 1 wt.%) and CNTs (0.2% and 0.6%) in water were prepared using cetyl trimethylammonium bromide (CTAB) surfactant and ultra-sonication energy and (b) the suspensions were subsequently added to cement/sand mixture to fabricate cementitious composites. The composite samples were kept for 56 days to carry out hydration and were then characterized for flexural properties. It was observed that flexural strength of cement mortar improved significantly when it was reinforced with MCC and CNT together. The highest improvement of flexural strength of 12.14% was achieved with MCC loading up to 0.5 wt.% and CNT of 0.3 wt.%. Considerable improvement in the flexural modulus of cement mortar was also achieved using this hybrid reinforcement system, info:eu-repo/semantics/publishedVersion

As crescentes necessidades de otimização na área da engenharia civil, tanto no que se refere à velocidade e logística das construções quanto nos aspectos da qualidade e durabilidade dos edifícios, combinadas ao elevado impacto dos materiais estruturais tradicionais nas dimensões econômica, social e ambiental da sustentabilidade, tornam necessário o estudo de elementos construtivos alternativos. Dentre as soluções, estão os polímeros reforçados com fibras (FRP), materiais que, devido às suas características superiores em relação aos convencionais, apresentam várias aplicações potenciais, especificamente os varões compósitos entrançados (BCR) reforçadas com fibras de vidro e/ou carbono que possuem, quando comparadas ao aço, elevado desempenho mecânico, leveza e reduzidos consumos energéticos de produção. Apesar dos avanços, ainda há insuficiente conhecimento a respeito da longevidade destes varões no interior do concreto empregado em elementos estruturais. Deste modo, este trabalho objetiva a avaliação da influência da camada externa na durabilidade de varões compósitos entrançados para tal fim. Para tanto, foram produzidas quatro amostras com reforço constante de fibras de vidro e carbono, com diferentes matrizes epoxídicas termoendurecíveis (tipo 1 e tipo 2) e dois tipos de fibras (poliéster e acrílico), as quais foram submetidas a condições e ambientes agressivos, designadamente, soluções alcalina em temperatura elevada e de cloretos e exposição a raios UV e humidade. Foram ainda desenvolvidas verificações acerca das propriedades físicas, químicas e mecânicas dos provetes, através de análise microscópica, verificação da variação de massa e de diferença de cor, da realização de espectroscopia infravermelho e ensaio de tração. Ao fim dos ensaios, constatou-se que a configuração de matriz formada por fibra acrílica impregnada com resina tipo 2 é a que apresenta melhores resultados e que os BCR mostraram, de modo geral, bom comportamento ao fim dos 80 dias de ciclo, apresentando adequadas propriedades após a exposição aos ambientes deletérios., info:eu-repo/semantics/publishedVersion

A elevada vulnerabilidade sísmica das paredes de enchimento em alvenaria tem conduzido à necessidade de reforço deste tipo de paredes, utilizando técnicas convencionais ou usando materiais inovadores. Os Fiber reinforced polymers (FRP’s) são utilizados principalmente como materiais inovadores para o reforço de estruturas. Apesar das vantagens associadas ao uso deste tipo de materiais, esta técnica de reforço apresenta algumas desvantagens, como problemas de aderência, mau comportamento à humidade e ao fogo. Uma solução possível para os problemas associados a estes materiais, pode passar pela substituição de agentes ligantes orgânicos para os inorgânicos, tais com argamassas à base de cimento. As interações entre as fibras e a matriz e também as condições de aderência em compósitos cimentícios pode ser melhorado através da utilização de malhas de reforço embebidas na argamassa de reboco, técnica habitualmente designada em língua inglesa por textile reinforced mortar (TRM). Esta técnica é relativamente nova (utilizada desde dos anos 80), tendo sido estudada por vários investigadores em diferentes aplicações. Neste artigo, investiga-se a utilização desta técnica no reforço de paredes de enchimento de alvenaria para ações no plano que simulam a ação sísmica. Foram ensaiados no plano, três provetes à escala reduzida, representativos da construção dos anos 70 em Portugal, um provete de referência, um provete reforçado com uma malha comercial e um provete reforçado com uma malha de reforço desenvolvida para o efeito. Neste caso as malhas de reforço foram desenvolvidas na Universidade do Minho no departamento de engenharia têxtil. A eficácia da técnica desenvolvida foi comparada com soluções comerciais., The high seismic vulnerability of masonry infilled frames have lead to their in-plane and out-of-plane strengthening by means of conventional techniques or by using innovative materials. Fiber reinforced polymers (FRP’s) are mostly used as innovative materials for retrofitting of structures. In spite of many advantages associated with use of FRPs, this retrofitting technique is not problem-free One possible solution to the problems of FRPs could be the replacement of organic binders with inorganic ones such as cement based mortars. Fiber-matrix interactions and also the bond conditions in cementitious composites could be improved if the fibers replaced with textile sheets. This lead to the formation of textile reinforced mortar (TRM) technique. This technique is relatively a new technique (it was started to use in early 1980s) and was studied by few researchers. In this paper, in-plane retrofitting of the infilled frames was investigated by using textile reinforced mortar (TRM) technique. Three half scale specimens which are representative of construction of 1970s in South European countries, were tested in the in-plane direction, a reference specimen, specimen retrofitted by commercial TRM technique and specimen retrofitted with developed TRM technique. In the developed TRM technique the textile meshes were developed and produced in the Textile Department. The effectiveness of the developed technique was compared with commercial solutions.

The thermal insulation in targeted textile substrates for home textiles assumes particular interest nowadays. Increasing performance and decreasing thickness are critical challenges to provide the required comfort to users during their rest period. Thermal insulation is associated with the phenomenon of heat absorption/desorption influencing the insulation value in fibrous material, since fibers absorb or release moisture, depending on their chemical composition. Thus, regarding thermal insulation, there are two major parameters to take into account: the conductivity and heat resistance. The main objective of this work is to study the performance of different fibrous structures for home textiles applications in terms of thermal insulation. The innovative structures considered within this study include non-woven fabrics produced with wool and hollow polyester fibers incorporating cork. Non-woven structures have been prepared in different compositions including 75%/25% wool and hollow polyester, 50%/50% wool and hollow polyester, blended with 25 mm cork granules size in proportions of 5% and 10% or with an agglomerated cork panel of 0,8mm. After production, samples were tested for their thermal behavior using Alambeta equipment. Results show that the non-woven composition influences greatly the thermal performance and the best result is obtained for sample with 50/50% wool and hollow polyester.

Crime increases year after year. Aggressions using knives, other cut and puncture elements are increasing greatly leading to a real need for security personnel protection, whether public or private, as weapons used are often improvised and can cause damage in various human body parts or even death. This work is focused on the study of fibrous materials to be used in cut protection clothing. Different knitted fabrics were produced in single jersey based weft knitted with yarns of different compositions, including ultra-high molecular weight polyethylene, para-aramid, high tenacity polyester, high tenacity polyamide and high tenacity polypropylene. Tests have been conducted to analyse the cutting performance index according to the EN388 standard that defines the material performance according to a scale from 0 to 5. The number of cycles required for a material to be cut determines the performance index, which is subsequently converted to the referred scale, where 0 refers to a material that presents no resistance to cut and 5 the material with greater resistance. From the results obtained it was possible to verify that the jersey structure produced with the ultra-high molecular weight polyethylene presents the best performance (4 in the above mentioned scale) and the worst performance is from the jersey structure produced with high tenacity polypropylene yarns that obtained the classification of 1.

Interactive textiles based on electrically conductive yarns are being extensively research due to its ability to functionalize fibrous structures, leading to a high interactivity with the user. The aim of this study was to evaluate the durability of interactive embroidered 100% cotton fabrics, incorporating flexible conductive yarns composed of 77% polyamide (PA) and 23% silver (Ag) (30 tex) when subjected to wear factors such as washing, abrasion, creasing and stretching cyclic tests. The conductive yarns were incorporated on the fabric at two different widths of 2 to 10 mm, keeping a constant length of 10 cm. In order to study the durability of these materials, the fabrics were subjected to different washing cycles, according to the standard NP EN IS0 6330:2002, and to various abrasion cycles, according to the standard NPEN IS0 12947: 1999 showing an increased electrical resistance when testing time is increased. The increase on the electric resistance was more significant in the 2 mm width sample rather than the 10 mm sample. The recovery from creasing, measured according to standard NP EN 22313:1993, was further assessed and no significant changes were observed. It could be concluded that the durability of conductive embroidered textile substrates in terms of washing and abrasion is highly dependent on the width of the conductive yarns embroidered area to perform the function. Larger conductive embroidered areas were found to be significantly more stable to wear factors.

This chapter presents an overview of the applications of braided structures in civil engineering. A brief introduction is provided on fiber reinforced plastics (FRPs), different fibers, and polymeric resins used in civil construction. More specifically, this chapter discusses the utilization of braided structures in concrete reinforcement and masonry wall strengthening. Particular focus has been given on the recently developed braided composite rods (BCRs), and for each of these applications the technique for producing BCRs or BCR-based materials, application methods, and obtained results are discussed in detail. The comparison of performance of braided structures with that of conventional FRP-based materials is also presented in this chapter.

This article is intended to evaluate the density and the mechanical, acoustic and thermal properties of compression moulded plates composed of granulate from electrical cables wastes. Those cable wastes are the insulation part from the electric cables, and are composed of PVC, PE, EMP and PEX rubber. After these materiais lose their initial properties and cease to be useful as insulation material, due to safety requirements, it is possible to reuse them into new applications like industrial or playground floorings, as sound insulation material to be applied in walls or floors, or to dampen vibrations from equipments. Recovering electric cable waste has been a major concern to the European Commission due to its leveis of toxicity when incineration and land fill ing is the solution to dispose this material. Such as the European Commission's study for DG Xl[1] suggested that recycling may be the most favourable future waste management option.

This work presents a study on the properties of chicken plumes from the poultry industry, namely feathers. Studies conducted include length, diameter and weight of chicken feathers to 42 days old. Initial results indicate that the central and lower feather areas present very interesting properties and characteristics turning these materials suitable for various applications, including in clothing, thermal and acoustic insulation in buildings, cimenticious and polymeric matrices reinforcements, among others., ACKNOWLEDGMENTS: CAPES Foundation, Ministry of Education of Brazil, Proc. nº 8976/13-9

Pedido de patente provisório nº 20151000053763, data de pedido 18 março 2015, em parceria com a Empresa Barcelcom, S. A..

Stents são estruturas entrançadas utilizadas no tratamento de doenças cardiovasculares, uma vez que previnem ou impedem a constrição do fluxo sanguíneo. A sua forma tubular é essencial para que consiga atingir a sua finalidade e manter o normal fluxo sanguíneo nos vasos sanguíneos. Neste trabalho foram desenvolvidos stents fibrosos entrançados, à base de poliéster (PES), poliamida (PA) e polipropileno (PP). Além disso, as propriedades mecânicas, que são influenciadas pelo ângulo de entrançamento e o diâmetro do mandril, foram testadas e discutidas. Este trabalho mostra que os stents fibrosos apresentam propriedades mecânicas adequadas e elevado potencial de mercado, Fundação para a Ciência e Tecnologia (FCT) através da bolsa de doutoramento SFRH/BD/90321/2012

Auxetic materials are a class of materials behaves unusual way compared to regular materials i.e. possess negative Poisson’s ratio. This paper reports, the development of auxetic structures based on re-entrant hexagon design from braided composite materials and testing of the mechanical properties (tensile property, auxetic property and work of rupture). The structure developed from glass and basalt braided composite rods and properties were compared between them. Later, the basic re-entrant hexagon design was modified with vertical straight rods to improve their mechanical behavior and their auxetic property was studied. Auxetic behavior of these structures was studied in a tensile testing machine taking video during testing by Digital camera, later the video converted into images to measure the strain values using simple software, ImageJ. Along with experimental work, analytical model was used to calculate the Poisson’s ratio of basic structure and results were compared, The authors gratefully acknowledge the financial support for carrying out this research work from University of Minho, under the scheme of “Strategic plan of school of engineering – Agenda 2020: Multidisciplinary projects.”

Natural Fiber Composites based on polypropylene have gained increasing interest over the past two decades, both in the scientific and industry communities. In this study, the mechanical properties of polypropylene (PP)/natural fiber composites were studied and compared with those of polypropylene reinforced by glass fiber. Flax and jute woven fabrics have been used. PP/glass fiber composites showed better performance in terms of tensile properties., The authors gratefully acknowledge the funding by QREN, Portugal, under the grant with reference 2014/38496.

O conceito de qualidade de vida surge pela primeira vez em 1920, através do economista inglês Arthur Cecil Pigou, que utiliza este termo para descrever o impacto governamental sobre a vida das pessoas mais desfavorecidas. Com a instalação de uma era industrializada e com o fim da 2º Guerra Mundial, a sociedade mudou de paradigma e iniciou uma procura incessante de formas para melhorar a sua qualidade de vida. Este conceito desenvolve-se juntamente com o desenvolvimento do conceito de educação, saúde, habitação, transporte, trabalho e lazer, bem como indicadores do aumento da esperança de vida, a diminuição da mortalidade infantil e dos níveis de poluição. O avanço da tecnologia teve um papel fundamental para a evolução desses conceitos, bem como o Design na procura de soluções para aplicação dessas mesmas tecnologias. No caso concreto da indústria tèxtil, a tendência é o desenvolvimento de têxteis inteligentes envolvendo a engenharia electrónica no seu processo de conceptualização e de fabrico. A chamada tecnologia wearable abre novos horizontes para a criação de soluções inovadoras, abrindo novos nichos de mercado com elevado valor acrescentado. Existem atualmente vários produtos no mercado cuja funcionalidade e utilidade lhes conferiu um estatuto imutável ao longo dos anos, onde a evolução não avançou na tendência atual. Esse é o caso dos tecidos estreitos, cuja funcionalidade poderá adquirir novas capacidades e ser utilizada em diferentes componentes têxteis nas mais variadas áreas. Essas capacidades poderão ser acrescentadas pela incorporação de materiais com luminosidade (Led’s e L-Wire) nas suas estruturas. Neste estudo realizado o design de produtos com novas funcionalidades, adaptando as tecnologias até agora desenvolvidas em novas soluções e/ou novas recriações de produto., The concept of quality of life appears in 1920, through the british economist Arthur Cecil Pigou, who uses this term to describe the government's impact on the lives of the most underprivileged. With the installation of the industrialized era and the end of the World War two, the society changed the paradigm and began a constant search for ways to improve their quality of life. This concept is developed along with the development of the concept of education, health, housing, transportation, work and leisure, as well as indicators of increased life expectancy and decreased infant mortality. The evolution of technology had played a key role in the evolution of these concepts as well as the Design in finding solutions for application of these technologies. In the case of the textile industry the trend is the development of smart textiles involving electronic engineering in the process of conceptualizing and manufacturing. The result is the wearable technology that open new horizons for creating new solutions, opening new market niches with high added value. Currently there are several products on the market whose functionality and utility gave them an immutable status over the years, and the product evolution has not advanced in the current trend. This is the case of ribbon, whose functionality can acquire new skills and be used in different textile components in various areas. These capabilities may be added by the incorporation and variation of color. As an example with the ability to become photochromatic materials (with a variation of light), thermochromic (with temperature variation), electrochromic (with electricity variance) mecanic-chromic (with voltage variation and / or strain) and also the possibility of incorporating luminescent coatings and the incorporation of luminescent materials in the structure. In this study will be developed an product design with new features and adapt the technologies so far developed in new solutions and / or new product recreations, Este trabalho foi desenvolvido no âmbito do projeto n.º 2014/37658 “NarrowTECH – Tecidos estreitos multifuncionais “, liderado pela empresa IDEPA e co-financiado pelo Fundo Europeu de Desenvolvimento Regional FEDER, através do COMPETE – Programa Operacional Fatores de Competitividade

Current societal challenges increasingly demand the need to seek for efficient and sustainable solutions to daily problems. Construction, as a result of its activity, is one of the main responsible industry for the exploitation of resources and greenhouse gas emissions. In this way, several research works are being undertaken to change some of the current practices. This paper presents the work being done at University of Minho to study de degradation of natural fibers when used as a sustainable solution for soil reinforcement. Jute and sisal fibrous structures (0º/90º) were studied in terms of their degradation over time, when incorporated into soil and when subject to accelerated aging tests in a QUV weathering test equipment. Results show that the process of biodegradation of natural fibers is clearly accelerated by the action of temperature, moisture and solar radiation, explaining further degradation of jute and sisal fibers when exposed to these factors, although more pronounced in jute fabric structures.

Commercial stents, especially metallic ones, present several disadvantages, and this gives rise to the necessity of producing or coating stents with different materials, like natural polymers, in order to improve their biocompatibility and minimize the disadvantages of metallic ones. This review paper discusses some applications of natural-based polymers in stents, namely polylactic acid (PLA) for stent development and chitosan for biocompatible coatings of stents . Furthermore, some effective stent functionalization techniques will be discussed, namely Layer by Layer (LBL) technique., The authors gratefully acknowledge the funding by Fundação para a Ciência e Tecnologia, FCT, Portugal, under grant SFRH/BD/90321/2012.

Stents are rigid and perforated tubular structures, which are inserted into blood vessels in order to prevent or inhibit the constriction of blood flow, restoring the normal blood flow, when blood vessels are clogged, being used in 70% of angioplasties. These medical devices assume great importance in the treatment of cardiovascular diseases (CVD) which are the leading cause of death worldwide. In the European Union CVD account for 40% of deaths and assume an estimated annual cost of 196 billion euros[1]. Stents must possess certain requirements, in order to, adequately, perform its function, such as biocompatibility (so that its use does not c ause damage on the health of its user), mechanical strength, radiopacity (so that it is easy to view), longitudinal flexibility, ease of handling, corrosion resistance and having high strength and high radial expansion ability to recover. Stents can be made of different materials, but metals, particularly stainless steel, are the most common. However, metallic stents present several dRawbacks such as corrosion and restenosis, leading to health complications for the patient, or even death. In order to minimize these disadvantages, new materials, like fibrous materials, have been used [2]. Monofilaments present high potential for stents development because, in addition to its biocompatibility, these materials allow the application of various surface treatments, such as antibacterial coatings. Furthermore, monofilament exhibit excellent mechanical properties, like greater stiffness and good results when subjected to compression, tensile and bending forces, since these forces will be directly supported by the monofilament [3]. To minimize the reaction of the human body and Limit the adhesion of microorganisms to the stent surface, some coatings have been developed, including the use of novel metals with antimicrobial properties, like silver. The main objective of this study was the development of fibrous stents, incorporation of silver oxide nanocoating. For the development of the stent, polyester monofilaments with 0.27mm of diameter were used in braiding technology, with a mandrel diameter of 6mm and a braiding angle of 35⁰. The mechanical behaviour of the stent were evaluated by mechanical testing under longitudinal and radial compression, bending. The results of compressive strength tests are according with value from literature: 1.13 to 2.9 N for radial compression and 0. 16-5.28N to longitudinal compression. From literature is also possible to verify that stents must present 75% of unchanged diameter during the bending test and must possess a porosity between 70% and 80% [4]. The produced polyester stent presents values of 1.29N for radial compression, 0.23N for longitudinal compression, 80% of porosity and 85.5% of unchanged diameter, during bending tests. For the antibacterial functionalization, silver oxide nanocoatings were prepared, through reactive magnetron g, with an Ag target in an Ar +O2 atmosphere. In order to evaluate the nanostructure and morphology of the coatings, d ifferent technique s like X-ray diffraction (XRD), scanning electron microscopy (SEM) and and X- ray photoelectron spectroscopy (XPS were used. From the analyses of XRD it is possible to verify that the peaks corresponds to planes of Ag2 O and MATERIAIS 2015 Porto, 21-23 June, 2015 characterize a cubic phase. The presence of Ag2 O is corroborated by XPS spectrum, where it is possible to observe silver, not only, in oxide state, but a lso in mettalic state, and it is possible to verify the presence of silver clusters, confirmed by SEM analysis. Films’ roughness and topography, parameters influencing the wettability of the surface and microorganism adhesion, were measured by Atomic Force Microscopy (AFM), and it was observed that the roughness is very low (under 10 nm). Coatings’ hydrophobicity and surface tension parameters were determined by contact angle measurement, and it was verified the hydrophobic behavior of the coatings. For antibacterial tests were used Staphylococcus epidermidis strain (IE186) and Staphylococcus aureus(ATCC 6538), and halo inhibition zone tests were realized. Ag+release rates were studied by means of inductively coupled plasma mass spectrometry (ICP -MS). The obtained results suggest that silver oxide coatings do not modify significantly surface properties of the substrate, like hydrophobicity and roughness, and present antimicrobial properties for both bacteria used.

This paper provides an overview of properties and application of natural fibre composites. Natural fibre market, merits and demerits, surface treatment techniques, properties of some recently developed natural fibre composites and applications have been discussed.

Due to remarkable physical properties, special surface chemistry and excellent biological properties, as low toxicity, biocompatibility and biodegradability, nanocellulose has gained much attention for its use as biomedical material, applied in medical implants, tissue engineering, drug delivery, wound-healing, cardiovascular applications, among others. This paper presents a review on nanocellulose applied in biomedical area., The authors gratefully acknowledge the funding by Ministério da Ciência, Tecnologia e Ensino Superior, FCT, Portugal under grant SFRH/BD/90324/2012.

This paper presents the results of experimental investigation on the aqueous dispersion behaviour of micro crystalline cellulose (MCC) prepared using Pluronic F-127. For this purpose, different concentrations (0.5-3.0 wt.%) of MCC were dispersed in water with the help of ultrasonication technique using various concentrations of Pluronic F-127. The homogeneity of the suspensions and agglomerations were characterized by optical and transmission electron microscopy and the concentration of well dispersed MCC was measured using UV-Vis spectroscopy. Also, the suspensions were subjected to high speed ultracentrifugation at 3000 rpm and observed visually for sedimentation and subsequently, concentration was calculated using UV-Vis, in order to assess the long term stability of the suspensions. Based on these experiments, optimum concentration of Pluronic to disperse different MCC concentrations has been suggested.

In this work, novel auxetic structure has been developed from braided composites produced from basalt fiber. The paper reported the auxetic and tensile behavior of the structures produced from basalt fiber and also compared with structures developed from braided composites having glass fiber as core. The basic design is modified with straight rod to improve the strengthening behavior of structure with structural elements. The Poisson’s ratio of the modified structure are studied. The Poisson’s ratio of the structure made from basalt and glass reinforced BCRs are almost similar but the tensile behavior of basalt based structure is good than glass fiber., The authors gratefully acknowledge the financial support for carrying out this research work from University of Minho, under the scheme of “Strategic plan of school of engineering – Agenda 2020: Multidisciplinary projects.”

Since they present a negative Poisson's radio, auxetic materials are different from conventional ones. These materials present an unusual behaviour: when stretched (elongated in the longitudinal direction), their cross-section is increased. There are two different ways to obtain auxetic materials: through polymers or through structures. It is possible to affirm that those obtained through fibrous structures are very recent and that few authors have been dedicated to their study. The main objective of this work is to study the effect of the negative Poisson􀂶􀁖 ratio in fibrous structures using flax fibres. The dimensional parameters of the fibrous structures have been varied and their influence on the auxetic behaviour assessed and analysed., The authors gratefully acknowledge the funding by CAPES Foundation, Ministry of Education of Brazil, Caixa Postal 250, Brasília ± DF 70040-020, Brazil, under doctoral grant BEX 0978/12-4

Concrete is the primary construction material for civil infrastructures and generally consists of cement, coarse aggregates, sand, admixtures and water. Cementitious materials are characterized by quasi-brittle behaviour and susceptible to cracking [1]. The cracking process within concrete begins with isolated nano-cracks, which then conjoin to form micro-cracks and in turn macro-cracks. Formation and growth of cracks lead to loss of mechanical performance with time and also make concrete accessible to water and other degrading agents such as CO2, chlorides, sulfates, etc. leading to strength loss and corrosion of steel rebars. To improve brittleness of concrete, reinforcements such as polymeric as well as glass and carbon fibers have been used and microfibers improved the mechanical properties significantly by delaying (but could not stop) the transformation of micro-cracks into macro forms [2]. This fact encouraged the use of nano-sized fillers in concrete to prevent the growth of nano-cracks transforming in to micro and macro forms. Nanoparticles like SiO2, Fe2O3, and TiO2 led to considerable improvement in mechanical performance and moreover, nano-TiO2 helped to remove organic pollutants from concrete surfaces [3].

This work intends to evaluate the mechanical properties of eco-composites reinforced with natural fiber fabrics in different fibrous arrangements, with a thermoset matrix of natural origin. When integrated by hand lay-up process, the composites obtained present excellent mechanical characteristics combined with environment friendly features, being able to be used in various industrial sectors.

Neste trabalho, multifilamentos ocos de polipropileno foram estudados com o objetivo de construir um fantoma cerebral adequado à validação e controlo de qualidade de uma modalidade de imagem clínica inovadora: High-Definition Fiber Tractography. Foram investigadas e discutidas a análise à secção transversal e a redução da área de multifilamentos ocos de polipropileno, através de estiramento. De acordo com os resultados experimentais, a dimensão da secção transversal dos multifilamentos é proporcional à massa linear dos mesmos, existindo uma irregularidade, relativamente, à forma deste tipo de materiais., Este trabalho é apoiado pela bolsa de doutoramento SFRH/BD/90324/2012 da Fundação para a Ciência e Tecnologia

This study compares the physicochemical characteristics of six species from Brazilian Malvaceae family with natural fibers of recognized applicability in the industry. The objective of the present study is present the physicochemical characterization of six Brazilian vegetal fibers: Sida rhombifolia L.; Sida carpinifolia L. f.; Sidastrum paniculatum (L.) Fryxell; Sida cordifolia L.; Malvastrum coromandelianum (L.) Gurck; Wissadula subpeltata (Kuntze) R.E.Fries. Respectively the two first species are from Brazilian Atlantic Forest biome and the four remaining from Brazilian Cerrado biome, despite of present in other regions of the plane, The authors gratefully acknowledge the funding by FAPESP (“Fundação de Amparo à Pesquisa do Estado de São Paulo”) and CAPES (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior) and CNPq (“Conselho Nacional de Desenvolvimento Científico e Tecnológico”)

The reinforcement of soil is defined as an effective and reliable technique to improve strength and stability. For this propose, the use of natural fibers has been commonly. Over the past years, a series of studies have been performed in order to investigate the influence of randomly oriented fibers, especially for compressible clayey soils. However, less attention has been given to the reinforcing of sandy materials, as well as the use of oriented fibers meshes in order to improve mechanical behaviour. The main aim of this study is to identify the influence that different percentages of fibers, as well as the use of meshes of oriented fibers, has on soil mechanical behaviour. For this purpose, unconfined compression tests with local strain measurements were performed on a silty sand reinforced with Sisal fibers and a comparative study between randomly oriented and 0° and 90° fibers is presented.

Eventos sísmicos têm demonstrado a vulnerabilidade de paredes de enchimento inseridos em pórticos de betão armado, sendo importante avaliar técnicas de reforço que possam ser implementadas em paredes existentes ou em construção, a fim de melhorar o seu desempenho sísmico. O presente trabalho surge no âmbito de um estudo que apresenta uma adaptação sugestiva de materiais convencionais (FRP), utilizando varões compósitos entrançados (BCR), através de malhas aplicadas no reboco de paredes usando a técnica de argamassa reforçada com têxteis (TRM). O comportamento fora do plano da alvenaria pode ser melhorado, assegurando uma aderência adequada entre a argamassa e os materiais de reforço. Uma campanha experimental foi realizada com diferentes varões e com diferentes características de superfície através de ensaios de arrancamento. Assim, é possível seleccionar a melhor tipologia de estrutura fibrosa que pode ser aplicada nas paredes, apresentando um comportamento apropriado em termos de aderência, evitando o deslizamento e roturas frágeis., Seismic events have been demonstrating the vulnerability of the infill walls inserted in reinforced concrete frames, being important to evaluate reinforcement techniques that can be implemented in existing walls or being built, in order to improve their seismic performance. The present work appears in scope of a study which provides a suggestive adaptation of the conventional materials (FRP) using a fibrous structure composed of braided composite rods (BCR), through of meshes applied on the rendering of the walls using the Textile Reinforced Mortar (TRM) technique. The out-of-plane behaviour of the masonry can be improved, but an adequate adhesion between mortar and reinforcing materials should be ensured. An experimental campaign was carried in different rods with different surface characteristics through pull-out tests. Thus, it’s possible to select the best typology of rod that can be applied on walls, presenting a suitable behaviour in terms of adhesion, avoiding sliding and brittle failures., Fundação para a Ciência e a Tecnologia (FCT)

Vol. 1, O Congresso Luso- Brasileiro de Materiais de Construção Sustentáveis decorreu em Guimarães, Portugal, de 5 a 7 de março de 2014. O tena de Materiais de Construção Sustentáveis é essencial para a indústria da construção e para o desenvolvimento sustentável dos países. É importante a reutilização de resíduos e a obtenção de materiais funcionais capazes de melhorar a qualidade do ambiente. É, também, importante que a indústria da construção seja inovadora e aceite novas soluções para resolver problemas com vários anos. O Congresso Luso-Brasileiro de Materiais de Construção Sustentáveis atraiu especialistas que apresentaram os resultados das suas investigações e discutiram as perspetivas de trabalhos futuros relativos a materiais sustentáveis e à sua importância para a obtenção de uma construção com elevada sustentabilidade. Os principais temas do congresso foram: Materiais e Energia, Materiais e Resíduos, Materiais Naturais e Materiais e Reparação.

Book of abstracts; ISBN 978-3-033-04763-1

Generally, current clinical imaging methods do not provide highly detailed information about location of axonal injury, severity of injury or expected recovery of patients with traumatic brain injury (TBI). High-Definition Fiber Tractography (HDFT) is a novel imaging modality that allows visualizing and quantifying, directly, the degree of axons damage, predicting functional deficits due to traumatic axonal injury and loss of cortical projections. This imaging modality is based on diffusion technology. Being a novel modality, validation and quality control are essential. Thus this study aims at the development of a brain phantom to mimic the human brain in order to fill some gaps that currently exist in this area. This paper is focused on this novel imaging approach, the role of brain phantoms on its validation and the quality control, as well as, on the materials used in their construction. Furthermore, some important characteristics of fibrous materials for brain phantom are also discussed.

Publicado em "Materiais de construção sustentáveis, ISSN 2183-1866, vol. 2", Estruturas fibrosas com base em fibras naturais têm ganho um espaço fundamental quando é necessário desempenhar funções de separação, drenagem, filtração, proteção e reforço, em solo. A utilização das fibras naturais torna as obras de engenharia mais sustentáveis, visto tratar-se de matérias-primas renováveis, biodegradáveis, de baixo consumo energético e não tóxicas. No presente trabalho estudou-se a influência da degradação provocada por raios ultravioleta, calor e humidade no comportamento mecânico de fibras naturais de origem vegetal usadas em geotêxteis, incluindo fibras de sisal, de banana e de coco. O estudo da durabilidade das fibras naturais incluiu ensaios de envelhecimento acelerado e ensaios em condições reais, em contacto com o solo, num período de 3 meses. Foram retiradas amostras em intervalos de 15 dias e realizados ensaios de caracterização mecânica de modo a avaliar o efeito dos parâmetros referidos. Os resultados obtidos permitem concluir que em todas as fibras estudadas se verifica uma degradação acentuada das fibras nos primeiros 15 dias. Este estudo mostra que as fibras de sisal e de banana, submetidas a degradação em solo, apresentam maior perda de resistência ao longo do tempo que as amostras submetidas a ensaios de envelhecimento acelerado em QUV. Na conceção de geotêxteis em fibra natural, é de salientar que as fibras de banana apresentam uma degradação muito acentuada tornando-as de difícil aplicação em geotecnia; as fibras de sisal e de coco apresentam características que as tornam apropriadas para desempenhar várias funções.

As estruturas compósitas multicamada têm-se assumido ao longo dos anos como sendo uma solução que vai de encontra aos requisitos estabelecidos pelas aplicações. Contudo, estes tipos de estruturas requerem determinados cuidados na sua conceção, nomeadamente na compatibilidade (coesão) entre as várias camadas, uma vez que a coesão entre os materiais é um fator crucial, para o desempenho das estruturas compósitas multicamada. Assim, este artigo relata a avaliação do poder de adesão entre derivados de madeira e fibras de vidro. Desta forma, os derivados de madeira utilizados foram: Aglomerado de madeira com uma espessura de 10mm e uma densidade de 620 kg/m3 ; MDF com uma espessura de 10mm e uma densidade de 800Kg/m3 ; Madeira de Pinho com uma espessura de 10mm e uma densidade 530 kg/m3 . No que diz respeito às fibras de vidro, foram utilizadas duas tipologias distintas: Tecido 1 é concebido por 6 fios/cm orientados a 0º e 8 fios/cm orientados a 90º e o Tecido 2, concebido por 4 fios/cm orientados a 0º e 5 fios/cm orientados a 90º. Os dois tecidos possuíam uma massa por unidade de superfície semelhante, 350 g/m2 .Também a dosagem da ligação e a pressão aplicada aos provetes, influência no poder de adesão das estruturas multicamada. No que diz respeito à ligação, esta foi promovida através de uma cola comercial, designada por Kaurit. De forma a avaliar a sua influência na adesão, foram utilizadas duas dosagens distintas (cola numa Face ou cola em duas Faces). A pressão aplicada aos provetes foi igualmente variada, sendo utilizada uma pressão de 25 bar e 50 bar. Para avaliar quais os parâmetros que promovem uma melhor ligação entre os materiais em estudo foram preparados um conjunto de provetes utilizado a moldação por compressão a quente, sendo que as condições de processamento utilizadas foram 112ºC durante 10min, variando os parâmetros pressão e quantidade de cola. Assim sendo, as combinações estudadas foram: Aglomerado de madeira/MDF e Aglomerado de madeira/Madeira de Pinho, quando é introduzido entre eles um tecido de fibra vidro ou sem tecido de fibras de vidro, sendo esta condição tomada como referência, ao que é produzido atualmente. Após a conceção dos provetes, foi avaliado o poder de adesão dos mesmos com a realização de um ensaio de flexão em três pontos tendo como referência a norma ASTM D790-03 no equipamento de ensaios mecânicos Hounsfield, modelo 100 KS. No que diz respeito aos resultados obtidos, pode-se verificar que a tipologia de tecido de fibra de vidro influência diretamente no poder de adesão entre os vários materiais. Em certas combinações verificou-se mesmo uma perda de adesão na ordem dos 66%, por outro lado em certas amostras foi verificado um incremento no poder de adesão na ordem dos 14% em relação à amostra referencia. Nos casos em que existiu um incremento da adesão, verificou-se que ocorreu o rompimento da ligação pelos materiais. Ao nível dos materiais utilizados, verificou-se que a sua tipologia influencia no poder de adesão. Desta forma o presente estudo permitiu concluir que existem diferentes variáveis no processo de combinação de estruturas multicamada. Em certos casos, torna-se mesmo necessário efetuar um estudo preliminar para o processamento das estruturas compósitas multicamada, com o objetivo de se obterem as melhores propriedades.

[Excerpt] An attempt has been made to develop DREF III friction spun yarn after structural modifications with an objective to analyze its feasibility for apparel end use by diagnosing its quantified reduction in harshness [1]. An independent study is carried out to develop a regression model, for simultaneous optimization of the desirability of physiological comfort and handle related properties of a knitted fabric, made up of the modified friction spun yarn, with predefined constraints in desired atmospheric conditions for specific end-use and comparing it with knitted fabric made up of conventional friction spun yarn named as ‘Reference fabric’ [2][3]. To optimize the desirability of value added garment, response surface methodology is used as a tool to develop a mathematical model [4]. In this work, ‘Physiological Control System’ (PCS) of both comfort & handle is being upgraded to ‘Engineering Control System’ (ECS) by conversion of conceptual model to a mathematical model [5]. Optimizing the fabric handle properties is based on the basic concept of neuroscience; artificial neuron model; physiological control system & engineering control system. Re-optimization of both comfort and handle by reverse engineering process is done to identify the best sample with maximum overall desirability termed as an ‘Ideal fabric’ to achieve value added quality garment. ‘Ideal fabric’ is identified as per the synergistic target & goal i.e. which satisfies & saddles both the parameters of comfort and handle in a compromise zone [6]. (...)