A exploração não racional dos recursos florestais nativos, no Brasil, tem provocado a redução da oferta de espécies de uso consagrado em diversos segmentos, notadamente na construção civil e na indústria de móveis. A alternativa mais imediata tem sido o emprego da madeira de reflorestamento, em particular, dos gêneros Eucalyptus e Pinus, freqüentes nas regiões sul e sudeste do país. Porém, muitas das espécies disponíveis comercialmente não apresentam propriedades fisico-mecânicas que as tornem capazes de promover a substituição das espécies tradicionalmente empregadas. Neste contexto, o presente trabalho tem como objetivo demonstrar a viabilidade de se obterem compósitos polímero-madeira (CPMs) que podem apresentar comportamento equivalente ou superior ao da madeira sem tratamento, proveniente das regiões de reflorestamento dos mencionados gêneros. Para tal, foi feita a impregnação da madeira das espécies Eucalyptus grandis e Pinus caribaea var. hondurensis por apresentarem maior disponibilidade e densidade compatível para viabilizar o processo. Empregaram-se os monômeros poliméricos de estireno e metacrilato de metila e, como iniciador no processo de polimerização, o peróxido de benzoíla. Foi utilizado o método de vácuo-pressão para a impregnação da solução monômero-iniciador. Os resultados mostraram, para os CPMs de Pinus, um significativo aumento nos valores de todas as propriedades estudadas. Nos CPMs de Eucalyptus, em decorrência de sua baixa permeabilidade, somente os valores das durezas paralela e normal às fibras apresentaram aumento. / Large exploration of native forestry resources in Brazil has led to a decrease in supply of the most widely used species in several sectors, notably in civil construction and furniture industries. The most immediate remedy has been the use of reforestation timber, obtained from the common Eucalyptus and Pinus species available in the south and southwest regions of the country. However, most of these species do not present adequate physical and mechanical properties to viably the mentioned uses. In this context, the main objective of the present research is to demonstrate the viability of obtaining wood-polymer composites (WPCs), which may exhibit similar or superior physical and mechanical properties than untreated aforementioned species from reforestation regions of Brazil. In order to achieve this goal, the impregnation of Eucalyptus grandis and Pinus caribaea var. hondurensis, which have compatible density and are available in large amounts to permit such processing, was carried out. In the process, polymeric monomers of styrene and methyl methacrylate were employed with benzyl peroxide, whose functions as an initiator in the polymerization process. Vacuum-pressure method was used in the impregnation of the monomer-initiator solution. Properties of the WPCs – Pinus were significantly improved in all tests, however, because of its low permeability, only hardness parallel and perpendicular to grain showed increase for the WPCs – Eucaliptus.

Diversos métodos de ensaios não-destrutivos (Ultrasom, Radiografia, Termografia e Shearografia) foram empregados na inspeção de peças laminadas estruturais compósitas sólidas de matriz polimérica manufaturadas pela indústria aeronáutica. Concluiu-se que Ultrasom pulso-eco convencional de contato foi a técnica mais abrangente na indicação de descontinuidades (danos/defeitos de manufatura) considerando-se peças planas e curvas, não obstante tenha falhado na detecção de trincas longas e bem definidas localizada na alma de componentes co-curados. Radiografia convencional por filmes exibiu um potencial interessante como método alternativo, ou complementar ao de Ultrasom. Termografia infravermelha foi a técnica mais veloz na indicação de descontinuidades, sendo uma valiosa alternativa para um mapeamento rápido em inspeções preliminares seguidas pela aplicação de técnicas complementares. Shearografia realizada com equipamento da empresa Photonita detectou inclusões em peça plana compósita, porém a interpretação dos resultados obtidos em geometrias mais complexas se mostrou duvidosa. O uso de equipamento shearográfico da empresa Dantec indicou posições em regiões curvas que podem estar associadas à presença de defeitos/danos locais, porém uma confirmação cabal desta relação não foi efetivada. Evidências visuais da profusa presença de danos/defeitos de manufatura, além da existência de detalhes construtivos nas peças compósitas mais complexas, sugerem que estas descontinuidades podem ter sensibilizado, em maior ou menor extensão, os equipamentos END, juntamente com a eventual presença de delaminações/falhas de adesão nas respectivas peças avaliadas. / Several nondestructive methods (Ultrasonics, Radiography, Thermography and Shearography) were employed for inspection of structural polymer matrix composite laminated parts manufactured by aircraft industry. Is has been concluded that conventional pulse-echo contact Ultrasonics was the most comprehensive technique to indicate discontinuities (manufacture damages/defects) in flat and curved parts, although it has failed to detect long and well-defined cracks in co-cured components. Conventional film radiography exhibited good potential as alternative or complementary method to Ultrasonics. Infrared thermography was the fastest technique to indicate discontinuities, so that it is a valuable option for rapid mapping in preliminary inspection followed by the application of complementary techniques. Sherography by means of Photonita equipment detected inclusions in flat panels, but the interpretation of results from pieces with more complex geometries was dubious. A shearographic of the Dantec device indicated positions in curved regions which might possibly be associated to the presence of damages/defects, however this relationship could not be definitively established. Visual evidences of the profuse existence of manufacture damages/defects, besides constructive details in more complex composite parts, suggest that theses discontinuities might have affected to some extent the NDT equipments, along with the eventual presence of delaminations/lack of adhesion on the respective evaluated parts.

Laminados compósitos com matrizes poliméricas foram submetidos à danificação mecânica por ensaios de flexão em três pontos e imersão prolongada em solução simuladora de fluido corporal (SBF). Uma das matrizes era composta de resina termorrígida epóxi reforçada com fibras de vidro (EPX-V) e fibras de carbono (EPX-C), enquanto que a outra era constituída por resina termoplástica poli sulfeto de fenileno reforçada com fibras de carbono (PPS-C). A absorção da solução pelos laminados compósitos e os danos neles inferidos foram avaliados pela técnica de imageamento por ressonância magnética nuclear (IRMN). A técnica mostrou-se eficaz na detecção de vários tipos de danos, como entalhes, delaminações, fissuras e deformações, e no controle de qualidade de biomateriais compósitos, desde que seus eventuais danos estivessem preenchidos por líquidos. A diferença na condutibilidade elétrica das fibras, isto é, baixa condutividade elétrica das fibras de vidro, em comparação com as fibras de carbono influenciou significativamente a qualidade das imagens. As imagens obtidas tinham menos artefatos no CDP EPX-V do que nos CDP de EPX-C e PPS-C. A diferença nos processos de manufatura também influenciou os resultados, para os CDP de EPX-V, oriundos de processo de manufatura menos criterioso, foi possível notar espaços vazios que foram preenchidos pela solução SBF e identificados nas imagens obtidas, por sua vez, nos CDP de EPX-C e PPS-C, que são produto de um processo de manufatura mais criterioso, o que lhes confere qualidade superior e menos defeitos, não foi possível identificar espaços vazios, ou pela sua inexistência ou talvez porque a resolução do equipamento não era alta o suficiente para capturar as imagens dos espaços vazios. Os resultados permitiram concluir que o imageamento via ressonância magnética nuclear é um método de inspeção eficiente e confiável para detecção de danos, in vitro, em laminados compósitos poliméricos reforçados tanto com fibras de vidro quanto com fibras de carbono. / Laminated composites with polymeric matrices were subjected to mechanical damage by bending tests at three points and prolonged immersion in a simulated body fluid solution (SBF). One of the matrices was composed of thermoset epoxy reinforced with glass fibers (EPX-V) and carbon fibers (EPX-C), whereas the other was constituted by polyphenylene sulfide thermoplastic reinforced with carbon fibers (PPS-C) The absorption of the solution by the composite laminates and the damage inflicted on them were evaluated by imaging technique via nuclear magnetic resonance. The technique showed efficient in the detection of various types of damage, as notches, delaminations, cracks and deformations, and control of the quality of composite biomaterials, as their damage was filled with liquid. The difference in the electrical conductivity of the fibers, i.e., lower electrical conductivity of the glass fibers in comparison to the carbon fibers significantly influenced the quality of the images. The images obtained had fewer artifacts in CDP EPX-V than those of CDP EPX-C and PPS-C. The difference in the manufacturing processes also influenced the results, as the voids of EPX-V CDP manufactured by a less careful process were filled with an SBF solution identified in the images. On the other hand, CDP EPX-C and PPS-C, which were the product of a higher quality manufacturing process showed no gaps, because the resolution of the equipment was not high enough to capture the images of the voids. The results show imaging via nuclear magnetic resonance is an efficient and reliable method for the detection of damage of in vitro polymeric composite laminates with glass fibers and carbon fibers.

Conventionally discrete passive components like capacitors, resistors, and inductors are surface-mounted on top of the printed circuit boards (PCBs). To match the ever increasing demands of miniaturization, cost reduction, and high performance in microelectronic industry, a promising approach is to integrate passive components into the board during PCB manufacture. Because they are embedded inside multilayer PCBs, such components are called embedded passives. This work focuses on the materials design, development and processing of polymer-based dielectric nanocomposites for embedded capacitor applications. The methodology of this approach is to combine the advantages of the polymer and the filler to satisfy the electric, dielectric, mechanical, fabrication, and reliability requirements for embedded capacitors. Restrained by poor adhesion and poor thermal stress reliability at high filler loadings, currently polymer-ceramic composites can only achieve a dielectric constant of less than 50. In order to increase the dielectric constant to above 50, effects of high-k polymer matrix, bimodal fillers, and dispersing agent are systematically investigated. Surface functionalization of nanofiller particles and modification of epoxy matrix with a secondary rubberized epoxy to form sea-island structure are proposed to enhance the dielectric constant, adhesion and high-temperature thermal stress reliability of high-k composites. To obtain photodefinable high-k composites, fundamental understanding of the photopolymerization of the novel epoxy-ceramic composite photoresist is addressed. While the properties of high-k composites largely depend on the polymer matrix, the fillers can also drastically affect the material properties. Carbon black- and carbon nanotubes-filled ultrahigh-k polymer composites are investigated as the candidate materials for embedded capacitors. Dielectric composites based on percolation typically show a high dielectric constant, and a high dielectric loss which is not desirable for high frequency applications. To achieve a reproducible low-loss percolative composite, a novel low-cost core-shell particle filled high-k percolative composite is developed. The nanoscale insulating shells allow the electrons in the metallic core to tunnel through it, and thereby the composites exhibit a high dielectric constant as a percolation system; on the other hand, the insulating oxide layer restricts the electron transfer between filler particles, thus leading to a low loss as in a polymer-ceramic system.

Die vorliegende Forschungsarbeit resultierte aus dem Ansatz, die theoretisch ableitbaren Vorteile der Werkstoffgruppe WPC (Wood Polymer Composite) zur Herstellung von Gleitelementen für fördertechnische Anwendungen (z.B. Gleitschienen in Stückgutförderern) zu nutzen. Diesem Ansatz lag der Gedanke zu Grunde, dass der anfängliche abrasive Verschleiß der polymeren Komponente als Schmiermittel den Abrieb und den Reibwert der stärker tragenden Holzkomponente verringert. Im WPC würde damit eine Funktionstrennung zwischen „tragendem“ Holz und „schmierendem“ Kunststoff vorherrschen. Darauf aufbauend erschien die These zulässig, dass sich im tribologisch aktiven Maschinenteil (Gleitschienen) die typischen Verschleißursachen hochbelasteter polymerer Gleitelemente wie einer starke Abrasion der Reibpartner, mechanische Überlast und damit Deformation in den Kontaktstellen und thermisch bedingter Verschleiß durch Temperaturstau in der Reibzone durch gezielten Holzzusatz in eine Kunststoffmatrix minimieren bzw. zu höheren Grenzen hin verschieben lassen. Diese These wurde in verschiedenen tribologischen Untersuchungen an spritzgegossenen und extrudierten Versuchskörpern grundlegend bestätigt. Die dargestellten Ausführungen zu den Untersuchungen gliedern sich inhaltlich in drei Schwerpunkte. Im ersten Punkt werden die Ergebnisse aus einfachen Tests zum grundlegenden Reibungsverhalten von WPC unter Nutzung des Stift–Scheibe–Versuches und einer nach praxisnahen fördertechnischen Anforderungen konzipierten Versuchseinrichtung vorgestellt sowie in den Stand der Technik eingeordnet. Die Praxisnähe der Versuche wird dabei durch die Probeauswahl weiter erhöht, indem Versuchskörper aus extrudierten Halbzeugen (Terrassendecks aus kommerziellen WPC) und Segmenten aus Förderketten ausgewählt werden. Die daraus resultierenden Aussagen ermöglichen erste Erkenntnisse hinsichtlich des dynamischen Reibwertes des WPC im relevanten tribologischen Belastungsspektrum für Gleitschienen. Im zweiten Punkt wird, aufbauend auf den gewonnenen Erkenntnissen, eine Betrachtungsweise vorgestellt, die neben dem Reibwert Aussagen zum Verschleißverhalten beinhaltet und eine vereinfachte Möglichkeit bietet, mittels des „Tribologiewertes“ die gewonnenen Erkenntnisse in einer praxisnahen Sichtweise darzustellen. Zudem wird die Versuchsmatrix hinsichtlich der verwendeten Parameter (Reibpartner, Reibgeschwindigkeit, theoretischer Flächenpressung) konkretisiert und erweitert. Die vorgestellte Betrachtungsweise und das verwendete Parameterfeld werden an spritzgegossenen Proben aus tribologisch „bekannten“ Materialien (Stand der Technik) und den Bestandteilen des untersuchten WPC (PP, PE, Fichte) überprüft. Weiterhin wird an vergleichbaren Proben aus WPC (50% PP / 50% Weichholz Fichte/Tanne) das tribologische Verhalten des Holzkunststoff - Verbundes klassifiziert. Dieses Verhalten wird hinsichtlich der tribologisch „bekannten“ Materialien in den Stand der Technik eingeordnet und eine These zum Wirkmechanismus bezüglich des Reibungs- und Verschleißverhaltens von WPC vorgestellt. Der dritten Punkt beinhaltet vertiefende Untersuchungen an spritzgegossenen Proben aus WPC mit 50% Weichholz und 50% PP - Matrix hinsichtlich des Einflussesder Spritzrichtung bzw. Holzpartikelorientierung, einer Wasserlagerung, der Konzentration des Haftvermittlers, einer Oberflächenbearbeitung. Weiterhin werden Aussagen zum Reibungs- und Verschleißverhalten von WPC mit PE-Matrix an spritzgegossenen Proben erarbeitet und eine erste Gegenüberstellung der Herstellungsverfahren Spritzguss und Extrusion vorgenommen. Die Untersuchungen ermöglichten in Summe das Gleitreibungs- und Verschleißverhalten des WPC grundlegend aber nicht vollständig zu charakterisieren. Die tribologischen Betrachtungen zur Werkstoffgruppe WPC stehen noch am Anfang ihrer Entwicklung. Die dargestellten Ergebnisse sind somit zudem als Startpunkt eines wissenschaftlichen Diskurses zu sehen.

Micromirror scanners are the most significant of the micro-optical actuator elements with applications in portable digital displays, automotive head-up displays, barcode scanners, optical switches and scanning optical devices in the health care arena for external scanning diagnostics and in vivo scanning diagnostics. Recent development in microscanning technology has seen a shift from conventional electrostatic actuation to electromagnetic actuation mechanisms with major advantages in the ability to produce large scan angles with low voltages, remote actuation, the absence of the pull-in failure mode and the acceptable electrical safety compared to their electrostatic counterparts. Although attempts have been made to employ silicon substrate based MEMS deposition techniques for magnetic materials, the quality and performance of the magnets are poor compared to commercial magnets. In this project, we have developed novel low-cost single and dual-axis polymer hard magnetic micromirror scanners with large scan angles and low power consumption by employing the hybrid fabrication technique of squeegee coating to combine the flexibility of polydimethylsiloxane (PDMS) and the superior magnetic performance of fine particle isotropic NdFeB micropowders. PCB coils produce the Lorentz force required to actuate the mirror for scanning applications. The problem of high surface roughness, low radius of curvature and the magnetic field interaction between the gimbal frame and the mirror have been solved by a part PDMS-part composite fabrication process. Optimum magnetic, electrical and time dependent parameters have been characterized for the high performance operating conditions of the micromirror scanner. The experimental results have been demonstrated to verify the large scan angle actuation of the micromirror scanners at low power consumption.

Submitted by Maria Medeiros (maria.dilva1@ufcg.edu.br) on 2018-09-25T12:44:58Z No. of bitstreams: 1 VALÉRIO CARLOS DE ALMEIDA CRUZ - TESE (PPGEP) 2013.pdf: 2545282 bytes, checksum: 3f37053bbbe74448ce66d692fa5819c1 (MD5) / Made available in DSpace on 2018-09-25T12:44:58Z (GMT). No. of bitstreams: 1 VALÉRIO CARLOS DE ALMEIDA CRUZ - TESE (PPGEP) 2013.pdf: 2545282 bytes, checksum: 3f37053bbbe74448ce66d692fa5819c1 (MD5) Previous issue date: 2013-02-28 / Capes / O presente trabalho tem como objetivo o estudo teórico/experimental da sorção de água em compósitos poliméricos reforçados com fibras de macambira (Bromélia Laciniosa). Foi utilizado como matriz polimérica uma resina de poliéster insaturado e fibras de Macambira originárias do cariri paraibano. Os compósitos foram confeccionados com 70% de poliéster e 30% de fibras cortadas em tamanhos de aproximadamente 3 cm. Os ensaios de sorção de água foram realizados com amostras de 3 mm e 6 mm de espessura nas temperaturas de 25, 50 e 70°C. Uma modelagem matemática tridimensional transiente foi usada para predizer a transferência de massa durante a sorção de água destes compósitos. A cinética de sorção de água nos compósitos mostrou ser influenciada pela sua relação área/volume. Verificou-se que em tempos curtos, aproximadamente 50 horas, e temperatura de processo mais elevadas, os corpos com maior relação área/volume apresentam uma maior velocidade de sorção. Em tempos longos, os compósitos com maior relação área/volume e maior temperatura de processo apresentam maiores teores de água sorvida. O teor de umidade de equilíbrio dos compósitos com 30% de fibras de Macambira apresentaram valores de 16,8%, a 25°C, 17,00% a 50°C e 19,10% a 70ºC, para as espessuras de 3 mm, e de 12,5% a 25°C, 15,8% a 50°C e 14,8% a 70ºC, para a espessura de 6 mm. Resultados teóricos do teor de umidade médio dos compósitos foram comparados com dados experimentais e um bom ajuste foi obtido. Desta comparação, os coeficientes de difusão de massa foram obtidos para cada condição experimental. / This reseach aims to study theoretically and experimentally water absorption in polymer composites reinforced with macambira fiber (BromeliaLaciniosa). As polymer matrix was used unsaturated polyester resin and macambira fiber from cariri region of the Paraiba state. The composite samples were manufactured with 70% polyester resin and 30% macambira fiber (3cm length). Experiments were carried out in samples with 3 and 6 mm thickness at the temperatures 25, 50 and 70ºC. A transient 3D mathematical model was used to predict mass transfer during water sorption of the composites. It was verified that the water sorption kinetic is affected by area /volume relationships. For short time, approximately 50 h, the sample with lower area/volume relationships and higherprocess temperature presents a larger water absorption velocity, and for long times, these samples presents higher equilibrium water content. Equilibrium moisture content of the samples were 16.8% at 25ºC, 17.00%. at 50ºC and 19.10% at 70ºC, for 3 mm thickness, and 12.5% at 25ºC, 15.8% at 50ºC and 14.8% at 70 ºC, for 6 mm thickness. Predicted results of the moisture content of the composites were compared with experimental data, and a good agreement was verified. From this comparison diffusion coefficients were obtained for different experimental conditions.

End-gated and centre gated mouldings have been assessed with varying thickness and sprue geometries for the centre gate. Alternative image analysis techniques are used to measure the orientation and length of injection moulded short and long fibres composite components. The fibre orientation distribution (FOD) measurements for both geometries have been taken along the flow path. In shear flow the FOD changes along the flow path, however the FOD remains relatively constant during expansion flow. The core width and FOD at the skin within a long glass fibre (LGF) specimen is different in comparison to a short glass fibre (SGF) specimen. Fibre length measurements have been taken from the extrudate, sprue and 2 positions within the centre gate cavity. The size of the sprue has little influence on fibre breakage if the moulding is more than 1 mm thick The SGF FOD prediction models within Autodesk Simulation Moldflow Insight 2014 (ASMI) have been validated against measured SGF data. At present, by default, the models over-predict the < cos2θ > for most geometries. When the coefficients are tailored for each model, drastic improvements are seen in the FOD prediction. The recently developed SGF RSC model accurately predicts the FOD in shear, in a thin geometry, whereas the Folgar-Tucker model predicts the FOD accurately in expansion flow. The measured LGF fibre length distribution (FLD) and FOD have been validated against the LGF prediction models. The LGF models are currently under predicting the breakage and over-predicting < cos2θ >. The breakage prediction improves if measured FLD of the extrudate is input into the model.

Laminados compósitos com matrizes poliméricas foram submetidos à danificação mecânica por ensaios de flexão em três pontos e imersão prolongada em solução simuladora de fluido corporal (SBF). Uma das matrizes era composta de resina termorrígida epóxi reforçada com fibras de vidro (EPX-V) e fibras de carbono (EPX-C), enquanto que a outra era constituída por resina termoplástica poli sulfeto de fenileno reforçada com fibras de carbono (PPS-C). A absorção da solução pelos laminados compósitos e os danos neles inferidos foram avaliados pela técnica de imageamento por ressonância magnética nuclear (IRMN). A técnica mostrou-se eficaz na detecção de vários tipos de danos, como entalhes, delaminações, fissuras e deformações, e no controle de qualidade de biomateriais compósitos, desde que seus eventuais danos estivessem preenchidos por líquidos. A diferença na condutibilidade elétrica das fibras, isto é, baixa condutividade elétrica das fibras de vidro, em comparação com as fibras de carbono influenciou significativamente a qualidade das imagens. As imagens obtidas tinham menos artefatos no CDP EPX-V do que nos CDP de EPX-C e PPS-C. A diferença nos processos de manufatura também influenciou os resultados, para os CDP de EPX-V, oriundos de processo de manufatura menos criterioso, foi possível notar espaços vazios que foram preenchidos pela solução SBF e identificados nas imagens obtidas, por sua vez, nos CDP de EPX-C e PPS-C, que são produto de um processo de manufatura mais criterioso, o que lhes confere qualidade superior e menos defeitos, não foi possível identificar espaços vazios, ou pela sua inexistência ou talvez porque a resolução do equipamento não era alta o suficiente para capturar as imagens dos espaços vazios. Os resultados permitiram concluir que o imageamento via ressonância magnética nuclear é um método de inspeção eficiente e confiável para detecção de danos, in vitro, em laminados compósitos poliméricos reforçados tanto com fibras de vidro quanto com fibras de carbono. / Laminated composites with polymeric matrices were subjected to mechanical damage by bending tests at three points and prolonged immersion in a simulated body fluid solution (SBF). One of the matrices was composed of thermoset epoxy reinforced with glass fibers (EPX-V) and carbon fibers (EPX-C), whereas the other was constituted by polyphenylene sulfide thermoplastic reinforced with carbon fibers (PPS-C) The absorption of the solution by the composite laminates and the damage inflicted on them were evaluated by imaging technique via nuclear magnetic resonance. The technique showed efficient in the detection of various types of damage, as notches, delaminations, cracks and deformations, and control of the quality of composite biomaterials, as their damage was filled with liquid. The difference in the electrical conductivity of the fibers, i.e., lower electrical conductivity of the glass fibers in comparison to the carbon fibers significantly influenced the quality of the images. The images obtained had fewer artifacts in CDP EPX-V than those of CDP EPX-C and PPS-C. The difference in the manufacturing processes also influenced the results, as the voids of EPX-V CDP manufactured by a less careful process were filled with an SBF solution identified in the images. On the other hand, CDP EPX-C and PPS-C, which were the product of a higher quality manufacturing process showed no gaps, because the resolution of the equipment was not high enough to capture the images of the voids. The results show imaging via nuclear magnetic resonance is an efficient and reliable method for the detection of damage of in vitro polymeric composite laminates with glass fibers and carbon fibers.

A exploração não racional dos recursos florestais nativos, no Brasil, tem provocado a redução da oferta de espécies de uso consagrado em diversos segmentos, notadamente na construção civil e na indústria de móveis. A alternativa mais imediata tem sido o emprego da madeira de reflorestamento, em particular, dos gêneros Eucalyptus e Pinus, freqüentes nas regiões sul e sudeste do país. Porém, muitas das espécies disponíveis comercialmente não apresentam propriedades fisico-mecânicas que as tornem capazes de promover a substituição das espécies tradicionalmente empregadas. Neste contexto, o presente trabalho tem como objetivo demonstrar a viabilidade de se obterem compósitos polímero-madeira (CPMs) que podem apresentar comportamento equivalente ou superior ao da madeira sem tratamento, proveniente das regiões de reflorestamento dos mencionados gêneros. Para tal, foi feita a impregnação da madeira das espécies Eucalyptus grandis e Pinus caribaea var. hondurensis por apresentarem maior disponibilidade e densidade compatível para viabilizar o processo. Empregaram-se os monômeros poliméricos de estireno e metacrilato de metila e, como iniciador no processo de polimerização, o peróxido de benzoíla. Foi utilizado o método de vácuo-pressão para a impregnação da solução monômero-iniciador. Os resultados mostraram, para os CPMs de Pinus, um significativo aumento nos valores de todas as propriedades estudadas. Nos CPMs de Eucalyptus, em decorrência de sua baixa permeabilidade, somente os valores das durezas paralela e normal às fibras apresentaram aumento. / Large exploration of native forestry resources in Brazil has led to a decrease in supply of the most widely used species in several sectors, notably in civil construction and furniture industries. The most immediate remedy has been the use of reforestation timber, obtained from the common Eucalyptus and Pinus species available in the south and southwest regions of the country. However, most of these species do not present adequate physical and mechanical properties to viably the mentioned uses. In this context, the main objective of the present research is to demonstrate the viability of obtaining wood-polymer composites (WPCs), which may exhibit similar or superior physical and mechanical properties than untreated aforementioned species from reforestation regions of Brazil. In order to achieve this goal, the impregnation of Eucalyptus grandis and Pinus caribaea var. hondurensis, which have compatible density and are available in large amounts to permit such processing, was carried out. In the process, polymeric monomers of styrene and methyl methacrylate were employed with benzyl peroxide, whose functions as an initiator in the polymerization process. Vacuum-pressure method was used in the impregnation of the monomer-initiator solution. Properties of the WPCs – Pinus were significantly improved in all tests, however, because of its low permeability, only hardness parallel and perpendicular to grain showed increase for the WPCs – Eucaliptus.