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Seismic isolation, in which a flexible layer is used to separate a structure from the ground below, is a proven method for reducing earthquake demands that has been recently introduced into the 2015 Canadian building code. Typical installations of seismic isolation use rigid diaphragms to bound the end plates of the isolators, which is easily implemented in new build scenarios but requires extensive excavation and foundation work in retrofit applications. An alternative form of isolation involves placing the isolation plane on top of first floor columns, potentially resulting in flexible boundary conditions. There have been very few experimental programs that mimic these flexible boundary conditions. To address conditions that may be found in column-top isolation design schemes, such as flexible framing and lightly axially loaded corner bearings, an experimental program on a quarter-scale column-top isolation system was conducted. The goals of the investigation were to investigate how rotations of both top and bottom bearing end plates impact key design assumptions such as horizontal stiffness, rotational stiffness, and stability, and how these effects change with axial load. Experimental findings showed that flexible boundary conditions reduce horizontal stiffness based on the sum of rotation at the ends, regardless of the rotation of one bearing end plate with respect to the other. This decrease is dependent on axial load, with more axial load leading to a higher decrease in horizontal stiffness. The rotational stiffness significantly decreases with bearing shear strain and models that use linear, elastic rotational springs underrepresent rotations at the boundaries. Lastly, traditionally used design limits for stability can be used for bearings of moderate shape factor (S1 = 19.6 used in testing) bounded by flexible framing, but these theoretical limits can overestimate the experimental determined limits by nearly double for bearings of low shape factors (S1 = 7.9 used in testing). / Thesis / Master of Applied Science (MASc) / Seismic isolation, in which a flexible layer is used to separate a structure from the ground below, is a proven method for reducing earthquake demands that has been recently introduced into Canadian building code. Typical installations of seismic isolation use rigid diaphragms to bound the end plates of the isolators, which is more easily implemented in new build scenarios but requires extensive excavation and foundation work in retrofit applications. An alternative form of isolation involves placing the isolation plane on top of first floor columns, potentially resulting in flexible boundary conditions. To address this, an experimental program on a quarter-scale column-top isolation system was conducted to investigate how rotations of both top and bottom bearing end plates impact key design assumptions such as horizontal stiffness, rotational stiffness, and stability. This research can help to expand the number and types of buildings isolation can be applied to, creating more resilient communities.

The focus of this research was to investigate the effect of thermal degradation upon the mechanical properties of natural rubber compounds and apply those effects to the life prediction of off axis 2-ply cord rubber laminates. The work examined both the quasi-static and dynamic mechanical properties of two natural rubber vulcanizates, which had been subjected to isothermal anaerobic aging. Thermal aging was performed on two different natural rubber vulcanizates. The thermal aging was conducted between the temperatures of 80 and 120°C for times ranging from 3 to 24 days. The effect of thermal degradation was measured from the changes in the chemical composition of the vulcanizates as functions of time at temperature. A master curve relationship between the changes in the chemical composition of the vulcanizates due to thermal degradation and their static and dynamic mechanical properties has been developed. This relationship allowed for the prediction of the vulcanizate mechanical properties after thermal aging. It was found that the mechanical properties correlated with the percentage of poly and monosulfidic crosslinks, where in general higher levels of polysulfidic crosslink gave rise to the highest mechanical properties. Crack propagation in an aged and unaged natural rubber vulcanizate was measured using a double cantilever beam, DCB. This type of testing arrangement exhibits a plane strain condition and resulted in crack growth rates two orders of magnitude faster than traditional plane stress testing geometries. To validate the DCB specimens, an investigation into the potential cavitation inside the rubber of the DCB specimens was performed. It was found that no cavitation occurred due to the high speed of the fracture. DCB samples were thermally aged to determine the effect of thermal aging upon the crack growth rate. It was found that crack growth rates increase with thermal aging. Life prediction of the aged 2-ply laminates was performed using a finite element analysis. In order to verify the finite element models used in the life prediction, the fatigue failure and crack growth characteristics of off axis 2-ply cord-rubber laminates were examined with a delamination analysis. This analysis allowed for the determination of the modulus of off axis 2-ply laminates in the presence of damage as well as the calculation of the crack growth rates of the laminate. The failure of unaged and thermally aged 2-ply laminates was evaluated and compared to the crack growth rates of thermally aged DCB specimens. The trend due to thermal aging between the two types of testing specimens was consistent. The finite element analysis was sectioned into two approaches: crack initiation and crack propagation. The former utilized a residual strength approach, while the latter applied a fracture mechanics approach. The predicted stress versus cycles, S-N, curves were not in complete agreement with the experimental data. The error between the predicted and the experimental is discussed and future work to correct that error is suggested. While there was not complete agreement between the predicted and the experimental data, this dissertation outlines a comprehensive approach to track the effects of thermal degradation and apply those effects to a real world application. / Ph. D.

Yes / Natural rubber (NR) and crosslinked polyethylene (XLPE) waste streams were devulcanized by solid state shear milling (S3M), producing a fine powder that may be more easily reprocessed. Understanding devulcanization and the nature of decrosslinked thermoset materials is of utmost importance for turning these waste steams into functional products. It was found that the devulcanized powders contained significant concentrations of radicals, which may be active in the subsequent revulcanization process. The produced devulcanized powders were converted into recyclable thermoplastic vulcanizates (TPVs) by twin screw extrusion. Reprocessing of these powders into value-added products is an important step in recycling and the use of extrusion allows for high throughput and industrial viability. Herein, we demonstrate that the optimal conditions for reprocessing are dependent upon the particle size of the devulcanized powder. Furthermore, dynamic vulcanization is affected by the nature of these recyclate powders. The successfully prepared TPVs showed similar properties to virgin materials, with a high elongation to failure. Therefore, the conversion of waste rubber into the rubber phase of a TPV shows significant promise in moving towards sustainable products, providing the revulcanization step can be well controlled. / EPSRC and NSFC for their funding of this work through the Joint UK-China Low Carbon Manufacturing Grant, Grant number EP/S018573/1.

Synthèse de nouveaux WPU (waterborne polyurethane) cationiques à partir du caoutchouc naturel (NR), et évaluation de leurs propriétés adhésives pour des surfaces de type cuir. Ces WPU ont été obtenus par réaction du caoutchouc liquide hydroxy téléchélique (HTNR), de toluene-2,4-diisocyanate (TDI), N-methyl diethanol amine (NMDEA, en tant qu’émulsifiant) et d’éthylène glycol (EG, extenseur de chaîne). Ces structures biosourcés sont développés comme alternatives aux WPU issus des ressources fossiles à fort impact environnemental. Les effets de cinq paramètres ont été étudiés, à savoir la quantité d'émulsifiant (de 0 à 2,25 mole), celle d’éthylène glycol (de 0 à 3 moles), le Mn du HTNR (de 100 à 3000 g/mole), l'indice NCO (de 100 à 150) et le taux d’époxydation des HTNR précurseurs (de 0 à 30%). Il a été en outre démontré que la stabilité des dispersions aqueuses pour les formulations optimales dépassait les 10 mois. La géométrie des particules dispersées a été étudiée, démontrant un aspect sphérique et une taille à l'échelle nanométrique. Ainsi, plusieurs facteurs ont été étudiés pour évaluer les propriétés adhésives optimales sur bandes de cuir (Mn, pourcentage d’'époxyde). Des tests standard (Peel test et Lap Shear test) ont été utilisés et les valeurs obtenues comparées avec celles issus de formulations adhésives commerciales avec ou sans solvants. Au bilan, une formulation optimale a été déterminée (Mn = 3000 g/mole, LR epoxydation = 10%, NMDEA 5.67%wt, NCO index de 100 et 1 mole d’EG) avec cuisson préalable des systèmes à 70°C. Ce WPU a montré une force d’'adhésion supérieure à toutes les formulations commerciales testées. / Novel cationic waterborne polyurethane (cWPU) based on natural rubber (NR) have been prepared by the polymerization reaction of hydroxyl telechelic natural rubber (HTNR), toluene-2,4-diisocyanate (TDI), N-methyl diethanol amine (NMDEA, as emulsifier), and ethylene glycol (EG, chain extender). The polyol structures have been developed as alternative to produce cWPUs derived from a renewable resource. The effects of five parameters were studied – amount of NMDEA (0 – 2.25 mole), amount of EG (0 – 3 mole), molecular weight of HTNR (~1000 – 3000 g/mole), NCO index (100 – 150), and epoxide content on eHTNR soft segment (0 – 30%). The appearance of cWPU dispersion was milky-blue with long shelf life time, more than 10 months. Particle of prepared cWPU were spherical shape in the nano range size. The adhesive properties of cWPUs on the real leather surface, taking into account of the different molecular weights of HTNR and different degree of epoxide content on HTNR, were tested by lap shear test and 180 degree peel test and compared with commercial adhesives. Overall, to balance the stability and adhesive strength, the best conditions for preparing cWPU adhesive for leather application in this study was from the composition of HTNR3000 with epoxide content of 10%, NMDEA 5.67%wt, NCO index of 100 and 1 mole of EG. in condition of curing at 70 °C. In comparison to non-solvent based and solvent based commercial adhesives, the adhesive strengths of these synthesized cWPU adhesive were superior.

O látex de borracha natural foi formulado, radiovulcanizado e, em seguida, estabilizado radioliticamente (GAMATEX), para ser empregado na fabricação de artefatos de borracha utilizados na área médica. A eficiência de reticulação do látex, quando radiovulcanizado com raios gama, correlacionou-se matematicamente com a razão de concentração do sistema de radiosensibilizador (x1 = [An-B] / [KOH]) e com a dose de vulcanização (x2), apresentando alto grau de interação, segundo o seguinte modelo matemático: , onde representa a resistência à tração na ruptura. O processo RVNRL foi otimizado para baixas doses de vulcanização e altas concentrações de An-B. A resistência radioxidativa da borracha, obtida a partir do GAMATEX, foi atingida adicionando-se uma mistura de antioxidantes (45% BANOX S + 55% TNPP). Esta mistura apresentou um efeito sinérgico. O látex apresentou comportamento pseudoplástico com a ocorrência de tensão de escoamento. A taxa de desestabilização irreversível do látex foi diretamente proporcional à [An-B] e inversamente proporcional à [KOH]. O efeito pós-irradiação do látex ou a desestabilização reversível, ocorreu devido à presença de uma concentração residual de An-B que não reagiu. A irradiação melhorou a estabilidade coloidal do GAMATEX, devido ao aumento da tixotropia e da tendência newtoniana além da correlação entre o grau de consistência (k) e o índice pseudoplástico (n), de acordo com o modelo matemático . Este fato permite um tempo maior de estocagem do GAMATEX. A viscosidade relativa do látex correlaciona-se com a temperatura e com o teor da borracha seca conforme o modelo matemático: , onde rw é a razão (BS/100-BS). O látex radiovulcanizado coagulou à temperatura de –10ºC no sistema de refrigeração projetado. / The natural rubber latex was formulated, irradiation vulcanized and stabilized (GAMATEX) to make rubber goods for medical purpose. When the latex was vulcanized by gamma rays the effectiveness crosslinking of GAMATEX relationship between the concentration ratio of sensitizer system (x1=[n-BA]/[KOH]) and the vulcanization dose (x2), showing high interaction grade according to the following the mathematical equation: , where is the tensile strength. The RVNRL process was optimized for low vulcanization doses and high concentrations of n-BA. The resistance to radiolitic oxidation of rubber obtained from GAMATEX was attained when one antioxidants mixture (45% BANOX S + 55% TNPP) was added. This mixture exhibited synergetic effect. The latex showed pseudoplastic rheological behavior and the yield stress occurrence. The irreversible destabilization rate of latex was direct proportional to [n-BA] and indirect proportional to [KOH]. The post-irradiation effects or reversible destabilization of latex occurred because there is a residual concentration of [n-BA] that it was not reacted. The colloidal stability of GAMATEX improved with irradiation, showing showing the increase of thixotropic behavior and the tendency to newtonian behavior flow besides the relationship between the viscosity index (k) and the pseudoplastic index (n) according to the mathematical model: . This fact allows the higher storage time of GAMATEX. The relative viscosity of latex was relationship between the temperature and the total dry rubber content according to the mathematical model: , where rw is the ratio (BS/100-BS). The radiation vulcanized latex coagulated at –10ºC into the projected freezing system.

L'objectif général de cette thèse était d'étudier les mécanismes microbiens intervenant dans l'évolution de la structure et des propriétés du caoutchouc naturel produit à partir du latex d'Hevea brasiliensis lors de la maturation du latex et des coagula de tasse. Pour cela, trois niveaux d'analyses ont été réalisés sur des expériences de maturation en conditions contrôlées : analyse de la structure et des propriétés du caoutchouc sec, analyse des flores microbiennes et analyses biochimiques. Après une phase de mises au point méthodologiques permettant notamment d'optimiser les conditions de maturation en chambre contrôlée et de définir une méthode d'extraction d'ADN adaptée au latex et au sérum de coagulum, des échantillons de caoutchouc sec et de sérum ont été produits à différents temps de maturation et selon différents traitements faisant varier trois paramètres : la présence de microorganismes, la présence d'oxygène, et le mode de coagulation du latex. Les analyses sur caoutchouc sec se sont portées sur la macrostructure (P0, P30 et PRI) et sur la mésostructure (Mw, Mn et gel total). L'analyse des flores microbiennes s'est appuyée sur plusieurs méthodologies complémentaires : comptages sur boîtes, dosage de l'ADN total, clonage/séquençage et pyroséquençage 454. L'objectif était d'évaluer la diversité des flores sur plantation et dans le latex ainsi que de suivre la dynamique de leur évolution au cours de la maturation en milieu contrôlé. Diverses analyses biochimiques ont réalisées sur latex, sérum et caoutchouc sec (taux d'azote, protéines, lipides, sucres, québrachitol, acides organiques). Les résultats obtenus ont ensuite été analysés en vue d'établir des corrélations et de proposer des mécanismes reliant l'évolution des propriétés du caoutchouc sec à celle de la biochimie du latex et des coagula et de leur évolution sous l'action des microorganismes et des enzymes, et de proposer quelques pistes en vue de l'amélioration des itinéraires techniques dans la filière. / The overall objective of this thesis was to study the microbial mechanisms involved in the evolution of the structure and the properties of the natural rubber from Hevea brasiliensis during the maturation of latex and cup-coagula. For this, three levels of analyses were performed on maturation experiments under controlled conditions: dry rubber structure and properties, biochemistry and microbial flora. After a methodology development phase aiming at (i) optimizing maturation conditions in a controlled chamber and (ii) defining suitable DNA extraction methods, samples of serum and dry rubber coagulum were produced at different times and under different maturation treatments varying three parameters: the presence of microorganisms, the presence of oxygen, and the latex coagulation method. Dry rubber analyses concerned macrostructure (P0, P30 and PRI) and mesostructure (Mw, Mn and total gel). The microbial flora was analyzed using several complementary methods: plate-counts, total DNA determination, cloning / sequencing and 454 pyrosequencing. The objective was to assess microbial diversity on field and in latex, and to follow the dynamics of their evolution during maturation in a controlled environment. Various biochemical investigations were performed on latex, serum and dry rubber (nitrogen content, proteins, lipids, sugars, quebrachitol, organic acids). The results were then analyzed for correlations to propose mechanisms linking changes in dry rubber properties, latex and coagula biochemistry, and their evolution under the action of microorganisms and enzymes. Some ideas for improving technical routes in the process are also proposed.

É grande o interesse em combinar as propriedades mecânicas e elétricas de diferentes materiais poliméricos. Neste trabalho, filmes de Borracha Natural com camadas superficiais condutoras de polianilina (PANI) são preparados e caracterizados por diferentes técnicas. A PANI dopada foi depositada em ambos os lados do filme de borracha por polimerização química \"in situ\" da anilina a temperatura ambiente. O processo da polimerização da PANI \"in situ\" foi otimizado variando a concentração dos reagentes químicos com o objetivo de se obter uma camada de PANI com espessura desejada, boa adesão na borracha e que produzisse também aumento da condutividade elétrica na superfície. As amostras obtidas são caracterizadas usando-se Microscopia Eletrônica de Varredura, Microscopia Óptica, Difratometria de raios-X, análise por Calorimetria Diferencial de Varredura, análise Termo-Dinâmico-Mecânica, análise Termogravimétrica, Espectroscopia no FT-IR, Ensaio Mecânico e condutividade elétrica na superfície e no volume dos filmes preparados. Os resultados mostram que os filmes produzidos são do tipo multicamadas, pois não há uma interpenetração da PANI na borracha. A melhor condutividade e uniformidade é obtida com filmes preparados com três deposições, atingindo a ordem de 10-7 S/cm / The combination of properties of different polymeric materials in one sample is of great interest. In this work natural rubber films covered with a layer of conductive polyaniline (PANI) were prepared and studied by means of several experimental techniques. The doped PANI layer was deposited onto both rubber films surfaces by the \"in situ\" polymerization technique. The polymerization of PANI was performed at room temperature and the deposition process was optimized in order to obtain a PANI layer with an adequate thickness, good adhesion to the rubber and to promote the increase of its surface electric conductivity. Samples were characterized employing the scanning electron microscopy, optical microscopy, X-ray diffractometry, differential scanning calorimetry, thermo gravimetric analysis, dynamic mechanical thermal analysis, mechanical analysis and surface/volume electric conductivity. Results showed that the formed films consisted of a PANI layer that did not penetrated in the rubber. The better uniformity of deposition and maximum electric conductivity of the order of 10-7 S/cm was obtained on films that were prepared by deposition of three PANl layers

Le caoutchouc naturel (CN) est un élastomère produit à partir du latex d'Hevea brasiliensis. Ce matériau est constitué en moyenne de 94% (m/m) de poly(cis-1,4-isoprène) et de 6% (m/m) de composés non-isoprènes avec notamment des lipides (1,5-3,0%), des protéines (~ 2,0%) et des éléments minéraux (0,2%). Ces composés non-isoprènes seraient responsables de la structure associative ainsi que des propriétés remarquables du CN. Ce matériau présente une grande variabilité de ses propriétés de mise en œuvre, liée aux conditions agronomiques (saison, clones, système d'exploitation) et aux différents procédés de fabrication existants. Le projet CANAOPT, dans lequel s'inscrit cette thèse, vise à identifier et à quantifier les sources de variabilité, ainsi qu'à développer de nouveaux grades de CN à variabilité réduite et contrôlée pour les applications antivibratoires. Ces travaux de thèse visent à mieux comprendre l'origine du gel du CN et son influence sur les propriétés rhéologiques du matériau. Cette phase gel (ou gel total) est constituée d'une fraction insoluble en solvant organique appelée le macrogel, et d'une fraction de microagrégats dispersés dans la fraction soluble et appelée le microgel.Le premier axe de recherche de cette thèse vise à identifier l'effet du gel sur les propriétés rhéologiques du CN. Dans ce but, des méthodes ont été développées afin de quantifier les différents taux de gels du CN, de caractériser la structure des chaînes de poly(cis-1,4-isoprène) et des microagrégats (SEC-MALS en mode TBABr), mais également de mesurer les propriétés rhéologiques en double cisaillement (DMTA). Une méthode permettant de caractériser rapidement le taux de composés non-isoprènes des échantillons par spectroscopie FT-IR a également été mise au point. Des corrélations ont d'abord été mises en évidence entre les masses molaires moyennes des macromolécules et les propriétés rhéologiques d'une sélection de 25 échantillons différents. Enfin, une corrélation a également été mise en évidence entre le taux de gel total et le paramètre K' décrit par le modèle de Perez. Ce paramètre est déterminé graphiquement par la représentation Cole-Cole. En parallèle, ces travaux se sont portés sur une caractérisation physico-chimique du microgel et du macrogel du CN. Une méthodologie d'extraction du microgel a été mise en place, et a permis la caractérisation des microagrégats du CN. La composition, le degré de réticulation, et les propriétés rhéologiques des macrogels issus d'une sélection de 11 échantillons de CN ont également été étudiés. Il a été montré que le taux de protéines contenus dans le macrogel (5-51% m/m) est directement lié à son degré de réticulation et impacte ses propriétés rhéologiques, très supérieures à celles du CN brut et de la fraction soluble correspondants. / Natural Rubber (NR) is an elastomer made from Hevea brasiliensis latex. It contains about 94% (w/w) of cis-1,4-polyisoprene and 6% (w/w) of non-isoprene compounds, such as lipids (1.5-3.0%), proteins (~ 2.0%) and minerals (0.2%). These non-isoprene compounds are assumed to be responsible for the associative structure and the outstanding properties of NR. However, substantial variability in NR properties is caused by diverse agronomic conditions (season, clones and tapping system) and by the different manufacturing processes. This PhD thesis is part of the French CANAOPT project, which aims to create new NR grades with reduced and controlled variability for antivibratory applications. This PhD work aims for a better understanding of the origin of the NR gel phase and its influence on rheological properties. The gel phase of NR (or total gel) is composed of a fraction that is insoluble in organic solvent (macrogel), and of microaggregates dispersed in the soluble fraction (microgel). The first component of this PhD research set out to identify the impact of the gel phase on NR properties. To that end, characterization methods were developed in order to investigate the different gel contents, the structures of cis-1,4-polyisoprene chains and microaggregates (SEC-MALS in TBABr mode), and also rheological properties in double-shear solicitation (DMTA) of NR samples. The non-isoprene contents (lipids and proteins) were also investigated using a new characterization method in FT-IR spectroscopy, developed during this PhD work. Correlations between the average molar masses of the macromolecules and the rheological properties of 25 NR samples were highlighted. Finally, a correlation was found between the total gel content and a K' parameter, introduced by the Perez model and graphically determined by the Cole-Cole representation.At the same time, physicochemical characterization of the microgel and the macrogel of NR samples was undertaken. First, a new method was developed in order to extract and study NR microaggregates. The composition, the degree of crosslinking and the rheological properties of macrogels extracted from 11 NR samples were also investigated. It was found that the protein content (5-51% w/w) of the macrogel was clearly correlated to its degree of crosslinking. The macrogel protein content also influenced its rheological properties, which were much greater than those of the corresponding NR and soluble fraction.

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No. of bitstreams: 1 bacarin_gb_me_prud.pdf: 3758371 bytes, checksum: 244ca14c0c0c6cad55915859de90f31d (MD5) Previous issue date: 2018-11-30 / Diariamente toneladas de resíduos industriais são gerados, os quais necessitam de estratégias de gerenciamento a fim de serem descartados ou reciclados corretamente. Por esse motivo, o reuso de resíduos orgânicos e industriais como cargas em compósitos poliméricos tem surgido como um novo campo de estudo. Nessa dissertação, demonstrou-se pela primeira vez o uso do resíduo Grits como carga natural em compósitos de borracha natural a fim de reutilizar os resíduos provenientes da indústria de celulose Kraft de eucalipto, assim como diminuir os custos de produção dos compósitos através da substituição, ainda que parcial, do carbonato de cálcio e do óxido de cálcio, cargas comerciais comumente utilizadas. Os tratamentos com Silano, Lauril sulfato de sódio, Dodigen 1611, além da correção de pH, variação da granulometria e quantidade de enxofre na formulação foram testados com a finalidade de melhorar a adesão interfacial do resíduo com a matriz polimérica, otimizar a formulação e consequentemente melhorar as propriedades mecânicas. Compósitos com 20 phr de Grits mostraram um aumento na tensão de ruptura de aproximadamente 20% comparado à borracha natural. Compósitos com 10 phr do resíduo apresentaram a maior resistência a abrasão, com 72,26 mm3 de perda por abrasão. Os compósitos foram aplicados na produção de chinelos atingindo as especificações recomendadas pelo Instituto de Ensaios e Pesquisa para a Fabricação de Calçados (PFI - Prüf- und Forschungsinstitut), Pirmasens, Alemanha. Ao compósito BN/20 phr Grits foi adicionado celulose de fibra curta de eucalipto para verificação da influência no tempo de degradação em solo. Amostras de celulose padrão, borracha natural, compósitos BN/20 phr Grits e BN/Grits/celulose foram expostos ao solo durante 180 dias para avaliação da biodegradação em solo, onde observou-se alteração na superfície das amostras após tempo de exposição. Os ensaios biológicos de toxicidade aguda e crônica não mostraram mortalidade significativa para a borracha natural e o resíduo Grits, assim como para os compósitos com boracha natural, Grits e celulose. / Daily tons of industrial residues are generated which require management strategies in order to correctly disposes or recycling. Therefore, the reuse of organic and industrial waste as fillers in polymeric composites has emerged as a distinct new field. Here, it was demonstrated for the first time the use of Grits as filler in natural rubber composites in order to reuse residues from eucalyptus cellulose Kraft industrie as well as decreasing the final cost from rubber products through calcium carbonate or calcium oxide replacement even partially. Treatments with Silane, Sodium Lauril sulfate, Dodigen 1611, besides pH correction, granulometry variation and sulfur content in the formulation were tested in order to improve the adhesion of the waste in the polymeric matrix, optimizing the formulation and consequently improving mechanical properties. The better treatment was prepared with pH correction and treatment with Dodigen 1611. Composites with 20 phr of Grits showed an increase on stress values around 20% compared to the natural rubber and, with 10 phr, presented the highest abrasion resistance of 72.26 mm3. The composites were applied on sandals production reaching the specifications recommended from Testing and Research Institute for the Manufacture of Footwear (PFI - Prüf- und Forschungsinstitut), Pirmasens, Germany. It was added eucalyptus cellulose fiber in order to verify the influence on soil degradation time. Standard cellulose, natural rubber, composites NR/20 phr Grits and NR/Grits/cellulose samples were exposed to the soil for 180 days to evaluate the soil biodegradation where it was observed a change in the surface of the samples after exposure time. Biological tests of acute and chronic toxicity showed no significant mortality for natural rubber and Grits waste, as well as composites with natural rubber, Grits and cellulose fiber.