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Metal foams have found increasing applications in a wide range of structural and functional products, due to their exceptional mechanical, thermal, acoustic and electrical properties and offer great potential for lightweight structures for energy absorption in packaging during impact at high velocities. Metal foam structures have densities only fractions of that of a solid structure and have high specific strength and higher stiffness than other contemporary packaging materials. Therefore, the metal foam in particular “Aluminium Foam” has an important application as packaging material for transportation of Reactor fuels and Radioactive samples. Nuclear materials are transported in packages which should meet stringent safety standards like impact resistance, thermal shock etc. Therefore, in the transportation of the above materials, aluminium foam can play a key role in providing a cushion for absorption of shock and impact. The aim of this work is to develop a process for fabrication of aluminum foam. Two methods are experimented to manufacture metal foams. The first method involves mixing of a foaming agent in a liquid aluminium pool and the subsequent cooling of the melt while hydrogen is released from the foaming agent. The second method of metal foaming process is based on a procedure consisting of a base metal and a foaming agent, which are milled for homogeneous mixing and then pre-compacted by cold isostatic pressing. This is followed by cold/warm extrusion. The extruded piece is then heated up to a certain foaming temperature. The heating process leads to partial metal melting as well as to the release of the hydrogen gas and consequently to the formation of metal foam in the semi-solid state. In this thesis, the technology for fabrication of Al foam having a density of around 0.2-0.3 g/cm3 has been made & discussed in detail. The effects of various fabrication parameters like compaction pressure, extrusion ratio and foaming temperature on the formation of the Al foam are discussed. The quality of fabricated Al foams is characterized in terms of density, microstructure, porosity content etc. The various mechanical properties like yield strength, tensile strength and impact energy of the Al foams are evaluated in order to understand their behavior under different conditions. The typical values of Young’s modulus, plateau stress, densification strain and energy absorbed for the foam tested are tabulated. The observations, which are made from the data, can be briefly quoted as under: a) As the length of the specimen increases, plateau stress increases which increases the energy absorption. b) The energy absorption for Al-20% Mg alloy has been found to be minimum. The foam exhibited brittle behaviour and crumbled under load application. c) Young’s modulus varies in the range of 0.057 – 0.13 GPa for the foam. d) As density increases, Young’s modulus also increases and correspondingly the energy absorption value increases for Al-foam. It is found that the variation in the plateau stress with density is marginal. But the strain value was found to be dependent on the alloy composition and the density. The strain obtained for all cases was found to be very near to 75-90%. Al-20%Mg alloy showed an inferior behaviour compared to pure Al. It showed a lesser plateau stress and crumbled while testing. This shows that this alloy is highly brittle in nature. Also, the Al-Mg foam obtained did not exhibited good luster.

Vycházíme-li z lehčených přírodních materiálů, lze od porézních materiálů s gradientem porozity očekávat mechanické vlastnosti nadřazené konvenčím polymerním pěnám, a to díky jejich specifické architektuře. Tyto vlastnosti umožňují použití lehčených materiálů jako strukturních prvků. V této práci je popsaná příprava gradientních porézních materiálů pomocí laminování a/nebo 3D tisku. Provedeny byly statické a dynamické mechanické testy na obou kvazi homogenních a gradientně porézních pěnách poskytující experimentální podklad pro hypotézu deformační odezvy plynoucí ze strukturní architektury. Data se interpretovala užitím zavedených teoretických modelů. Naše výsledky vedly k závěru, že tyto teoretické modely odvozené od pěn s pravidelnou strukturou není vhodné aplikovat pro pěny s gradientem porozity, protože prokazují podstatně lepší mechanické vlastnosti než homogenně porézní pěny.

The fundamental issue of determining acoustic properties of porous media from their local geometry is examined in this PhD dissertation thesis, thanks to a sample of open-cell aluminum foam analyzed by axial computed microtomography. Various geometric properties are measured to characterize the experimental sample at the cell size level. This is done in order to reconstruct a porous medium by means of idealized three- and two- dimensional unit-cells.The frequency dependant thermal and velocity fields governing the propagation and dissipation of acoustic waves through rigid porous media are computed by Brownian motion simulation and the finite element method, respectively. Macroscopic behavior is derived by spatial averaging of the local fields. Our results are compared to experimental data obtained from impedance tube measurements. Firstly, this approach leads to the identification of the macroscopic parameters involved in Pride and Lafarge semiphenomenological models. Secondly, it yields a direct access to thermal and viscous dynamic permeabilities. However, the bi-dimensional model underestimates the static viscous permeability as well as the viscous characteristic length; what thus require a three-dimensional implementation.

Dissertation (PhD)--University of Stellenbosch, 2000. / ENGLISH ABSTRACT: A mathematical model is presented which conceptualises fluid flow and heat transfer in cellular metallic foams completely saturated with a fluid in motion. The model consists of a set of elliptic partial differential governing equations describing, firstly, a momentum balance in the fluid by the spatial distribution of its locally mean velocity, and secondly, an energy balance in the fluid and in the solid matrix of the metallic foam, by the spatial and temporal distribution of their locally mean temperatures. The separate energy balance descriptions for the fluid and the solid matrix extend the application of the model to conditions of thermal equilibrium and thermal non-equilibrium between the fluid and the solid matrix. A computational solution algorithm is presented which allows the universal application of the model to porous domains of arbitrary shape, with spatially and temporally variable heat loads in a variety of forms. / AFRIKAANSE OPSOMMING: 'n Wiskundige model word voorgestel wat vloei en warmteoordrag voorspel in sellulêre metaalsponse wat in geheel gevul is deur 'n bewegende vloeier. Die vloeier kan in gasof vloeistoffase verkeer. Die model bestaan uit 'n stel elliptiese parsiële differensiaalvergelykings wat in die eerste plek 'n momentum-ewewig in die vloeier beskryf in terme van 'n ruimtelike, lokaal-gemiddelde snelheidsveld, en wat tweedens 'n energie-ewewig in die vloeier en in die soliede matriks van die metaalspons beskryf in terme van ruimtelike en tydelike lokaal-gemiddelde temperatuur verspreidings. Die aparte energie-ewewig beskrywings vir die vloeier en vir die soliede matriks van die metaalspons brei die aanwending van die model uit na gevalle waar die vloeier en die soliede matriks in termiese ewewig of in termiese onewewig verkeer. 'n Numeriese oplossingsalgoritme word ook voorgestel vir die universele toepassing van die model op ruimtelik-arbitrêre metaalspons geometrië wat onderwerp word aan 'n aantal verskillende ruimtelik-en tydveranderlike termiese laste.

Thesis (MBA)--Stellenbosch University, 2001. / ENGLISH ABSTRACT: The polystyrene foam tray manufacturing industry started with a monopoly in 1954, and lasted for more than 29 years. During the last ten years the industry has grown extremely competitive, seeing many new players enter (and exit) and a reduction in industry profitability. This mini thesis attempts to analyze the polystyrene foam tray manufacturing industry in its current form and to quantify the external, new challenges it currently faces. It attempts to identify potential pitfalls for new entrants to the industry and to construct an ideal strategy suited best for the industry, based on an industry analysis. The polystyrene foam container industry background is discussed to determine its origins in South Africa. An industry and competitive analysis is done to assess the strategically relevant aspects of the industry's macro environment. A technique developed by Thompson and Strickland (1998: 68) is utilized. The scope of the macro environment in the mini-thesis was limited to the South African scenario. Ultimately, an ideal strategy, which would deal with all the relevant challenges of the industry, is proposed. The industry and competitive analysis revealed important dominant economic traits. Competition is concentrated in the country's economic hub, namely Gauteng, but regional manufacturing bases leads to extended market share in those areas. The product range spans over several hundred coloured, printed and laminated trays, but the fiercest competition across the board takes place in a few sizes white, commodity flat trays to the meat industry, which also forms the bulk of sales to the industry. The growth rate has been organic for the last few years, mainly due to the mature status of polystyrene foam tray products and the introduction of alternative (though more expensive) media. The external macro economic environment has also not been conducive to abnormally high growth (GDP in South Africa has drifted between 1% and 3% for the last few years). Five competitors exist, and two of these competitors have 80% of the market share, but are also the furthest away from the largest part of the market, namely Gauteng. Customers are divided into two groups, distributors and end users. Small competitors make extensive use of distributors (since they do not own their own distribution channels), while large competitors limit the use of distributors to limit the potential buying power of distributors. The barrier to entry for a new entrant wanting to acquire up to 5% of market share is around R 10m, which includes working capital. The industry profitability varies from losses to extreme profits in some years. This becomes a vicious circle, since the latter attracts new entrants, which in turn causes price wars. Rivalry amongst competitive sellers is excessive, specifically when new entrants appear on the scene. Price cutting, although a very blunt tool, is used almost exclusively to obtain a volume advantage. Substitute products do not really pose a threat in the South African economic situation where cost is all-important. No other packaging medium can compete with the wide range of applicability, low cost and strength of polystyrene foam. Where end-user markets are more affluent, substitute products may have a minor impact. The power of suppliers in the industry is limited, since there is a manufacturing over capacity in the country, and there are no switching costs when changing from one supplier to another. The power of buyers, specifically ones that buy in bulk (distributors and the like), is thus quite strong. The main drivers of change include excessive movement in market pricing, product innovation, technological changes, increasing globalisation of the industry and changing societal concerns. Movement in market pricing is by far the most important and has the greatest affect on industry profitability, since the complete product range is affected. The latter four drivers affect mostly branded and speciality product. Strategic group mapping, combined with an in-depth analysis of each competitor, revealed that the largest two players, Kohler Versapak and Atlantic Forming, are definitely in the strongest position from a financial point of view. Although drawbacks such a corporate red tape, shareholder pressure and geographic location exist for these competitors, sheer financial strength to survive price wars will give them an edge. With the current amount of competitors and over capacity in the market there is bound to be some consolidation in the manufacturing industry. It seems that one of the larger two players (Kohler Versapak or Atlantic Forming) may acquire one of the smaller manufacturers in a bid to stabilize market prices. The most important key success factor is the ability to produce polystyrene foam trays at the lowest possible cost. The absence of switching costs, price wars and a manufacturing over capacity are all causes of the preceding success factor. Other less important success factors are distribution related (being close to the market is an advantage) and technology related (being able to develop advanced branded and functional trays). In its current status, where there is a supply-demand imbalance, the industry does not seem attractive. Although negative external forces such as environmental pressure, are limited, growth potential is limited and competition is fierce. In summary none of the competitors have attempted to utilize other tools than pricecutting to protect market share. From a geographic location point of view, Airshield and Mainpack are positioned best, but do not possess the financial momentum to optimally utilise their location in terms of finished product distribution and raw material acquisition. Atlantic Forming and Kohler Versapak seem to have expanded their product ranges to low profit and unprofitable products, while the other competitors have stayed focused on a few high volume items. It seems that it may have been a better idea for the larger players to utilize existing resources on other profitable media rather than expanding its interests in polystyrene foam trays. / AFRIKAANSE OPSOMMING: Polistireen skuim houer vervaardiging het in 1954 met 'n monopolie begin wat vir 29 jaar staande gebly het. Gedurende die laaste tien jaar het die polistireen skuim industrie baie kompeterend geraak, met heelwat kompeterende maatskappye wat die mark betree het (en uitgetree het), en 'n gevolglike afname in industrie profyt gehad het. Hierdie minitesis poog om die polistireen skuim bakkie industrie te analiseer in sy huidige vorm en om die eksterne uitdagings wat tans bestaan, te identifiseer. Die tesis poog verder om potensiele probleme te identifiseer wat nuwe kompeterende maatskappye in die industrie mag teëkom, en dan om 'n ideale strategie saam te stel, gebasseer op 'n industrie analise. Die polistireen skuim houer industrie is bespreek, sodat die oorsprong van die industrie in Suid-Afrika bepaal kon word. 'n Industrie en kompeterende analise is gedoen om die strategies belangrike aspekte van die industrie se makro omgewing te bepaal. Vir die bogenoemde analise is 'n tegniek soos ontwikkel deur Thompson en Strickland (1998: 68) gebruik. Die omvang van die makro omgewing in hierdie minitesis is beperk tot die Suid- Afrikaanse omgewing. Die uiteindelike ideale strategie sal al die relevante uitdagings van die industrie aanspreek. Die industrie en kompeterende analise het belangrike dominante ekonomiese eienskappe blootgelê. Markgerigte kompetisie is gekonsentreerd in die land se ekonomiese enjin, naamlik Gauteng, maar streeks gebaseerde vervaardigings aanlegte lei gewoonlik tot 'n verbeterde mark aandeel in 'n spesifieke streek. Die produk reeks bestaan uit honderde gekleurde, gedrukte en gelamineerde houers, maar die grootste kompetisie vind plaas oor slegs 'n paar plat, wit vleis bakkies - wat ook die grootste volume verkope in die industrie beslaan. Die groei tempo was organies vir die laaste paar jaar, hoofsaaklik as gevolg van die volwasse stand van polistireen skuim produkte en die bekendstelling van alternatiewe produkte. Die eksterne makro ekonomiese omgewing het ook nie bygedra tot bogemiddelde groei nie (BBP in Suid-Afrika het tussen I% en 3% gewissel vir die laaste paar jaar). Vyf produseerders van polistireen skuim houers ding mee in die mark, en twee van hulle besit 80% van die totale mark aandeel, alhoewel hulle ook die verste vanaf grootste mark, naamlik Gauteng, is. Kliënte word in twee groepe verdeel, naamlik verspreiders en eind-gebruikers. Klein produseerders maak meestal gebruik van verspreiders omdat hulle nie oor hulle eie verspreidings kanale beskik nie. Groter produseerders beperk die gebruik van verspreiders om uiteindelik potensiële koopkrag van verspreiders te beperk. Vaste kapitaal, asook lopende kapitaal om ongeveer 5% van die mark te bekom, is ongeveer R10m. Die industrie profyt variëer tussen verliese tot oorgrote profyt in sommige jare. Hierdie variasie vorm 'n afbrekende sirkel, aangesien oorgrote profyt potensiële nuwe produseerders aantrek wat dan weer tot prys oorloë lei. Mededinging tussen kompeterende produseerders is oormatig sterk, spesifiek wanneer nuwe produseerders die mark betree. Alhoewel prys verlaging 'n redelike kru metode is om markaandeel te bekom, word dit amper uitsluitlik gebruik. Alternatiewe, duurder vervangings produkte is nie werklik 'n gevaar vir polistireen skuim produkte in Suid-Afrika nie, aangesien prys die belangrikste element is. Geen ander verpakkingsmedia kan meeding met die toepasbaarheid, lae koste en sterkte van polistireen skuim nie. Slegs in sekere wel-gestelde segmente van die mark kan alternatiewe produkte 'n minimale impak op die polistireen skuim mark toon. Die mag van verskaffers in die industrie is beperk, aangesien daar 'n geweldige oorkapasiteit in die land is en omdat daar geen oorskakelingskoste bestaan wanneer daar van een verskaffer tot 'n ander geskuif word nie. Die mag van kopers, en spesifiek die wat in grootmaat koop, is dus redelik sterk. Die hoofdrywers van verandering sluit in sterk beweging in mark pryse, produk innovasie, tegnologiese veranderinge, toenemende globalisering van die industrie en veranderende sosiale standaarde. Variëerende beweging van markpryse is by verre die belangrikste en het ook die grootste effek op industrie profyt, aangesien die hele produk reeks geraak word. Die laaste vier drywers affekteer meestal handelsmerk produkte en spesialiteits produkte. Strategiese groep kaarte, gekombineerd met 'n indiepte analise van elke produseerder, het aangedui dat die twee grootste kompeteerders, Kohler Versapak en Atlantic Forming, definitief in die sterkste posisie is vanaf 'n finansiële oogpunt gesien. Alhoewel negatiewe punte soos korporatiewe sloering, aandeelhouer druk en geografiese posisie teen die twee mededingers tel, sal blote finansiele mag om prys oorloë te deurstaan hulle die oorhand gee. Met die huidige hoeveelheid oorkapasiteit in die mark moet daar uiteraard konsolidasie in die vervaardigings industrie plaasvind. Dit is waarskynlik dat een van die groter spelers (Kohler Versapak of Atlantic Forming) van die kleiner mededingers mag bekom in 'n poging om die mark te stabiliseer. Die mees belangrike sleutel sukses faktor is die vermoë om polistireen skuim bakkies teen die laagste koste te vervaardig. Die afwesigheid van oorskakelingskoste, die aanwesigheid van prys oorloë en vervaardigings oorkapasiteit is almal oorsake van die genoemde sukses faktor. Ander minder belangrike sukses faktore is verspreidings verwante (om nabyaan die mark te wees is 'n voordeel) en tegnologie verwante (om handelmerk produkte en moderne funksionele produkte te kan ontwikkel) faktore. In die mark se huidige vorm is daar nie 'n vraag-aanbod balans nie, en lyk die industrie nie aantreklik nie. Alhoewel negatiewe eksterne kragte soos omgewings druk beperk is, is groei potensiaal ook beperk en kompetisie agressief. Opsommendergewys het geen van die mededingers ander metodes as prys verlaging probeer gebruik om mark aandeel te beskerm nie. Vanaf 'n geografiese oogpunt gesien, is Airshield en Mainpack die beste geposisioneer, maar hulle het nie die finansiële momentum om hulle posisie optimaal te benut in terme van klaar produk verspreiding en rou material aankope nie. Atlantic Forming en Kohler Versapak het hulle produk reeks uitgebrei na lae profit en verlies-lyende produkte, terwyl ander mededingers gefokus gebly het op 'n paar hoë volume items. Dit lyk asof dit beter sou gewees het vir die groter spelers om bestaande bronne te gebruik het op ander winsgewinde media as om verder uit te brei in polistireen skuim.

L'objet de cette étude est de mieux formaliser et modéliser de façon générique le processus de structuration d'un produit par le procédé de foisonnement, en reliant les paramètres opératoires aux propriétés des mousses formées et de contribuer ainsi à un meilleur pilotage de l'opération. Une ligne de foisonnement par battage en continu a été instrumentée et l'évolution du diamètre des bulles en fonction des paramètres du produit et du procédé a été suivie pour des milieux modèles newtoniens et rhéofluidifiants. L'analyse dimensionnelle à l'échelle du procédé a permis d'aboutir à un modèle physique de l'opération, et donc d'avoir une compréhension des phénomènes en présence. Elle a aussi permis d'intégrer les paramètres du produit et du procédé et de simplifier la représentation des résultats expérimentaux. Enfin, la cohérence de ce modèle avec d'autres issus de la littérature et une première approche de validation avec un produit réel, semble justifier son caractère générique. / The aim of this study is to better formalize and model in a generic way the structuring of a product by the foaming operation process, by linking the operating parameters to the foams properties and contribute to a better steering of the operation. A continuous whipping line was instrumented and the evolution of bubble diameter depending on both product and process parameters was characterized for Newtonian and shear-thinning model fluids. Dimensional analysis of the process has lead to a physical model of the operation, and therefore makes possible the understanding of the phenomena involved. It also helped to integrate the product and the process parameters and simplify the representation of experimental results. Finally, the consistency of this model with others from the literature and a first validation with a real product seems to justify his relevance.

L'objectif de ce mémoire de recherche est de déterminer les propriétés acoustiques des milieux poroélastiques à partir d'une démarche multi-échelle et multi-physique. Il traite d'échantillons réels de mousses, à cellules ouvertes ou partiellement fermées, dont les propriétés microstructurales sont caractérisées par des techniques d'imagerie. Cette information est utilisée afin d'identifier une cellule périodique idéalisée tridimensionnelle, qui soit représentative du comportement acoustique du milieu poreux réel. Les paramètres gouvernant les propriétés acoustiques du milieu sont obtenus en appliquant la méthode d'homogénéisation des structures périodiques. Dans une première étape, la structure des mousses est supposée indéformable. Il a été montré que pour le cas d'une distribution étroite de tailles caractéristiques de la géométrie locale, le comportement macroscopique d'une mousse à cellule ouverte peut être calculé à partir des propriétés géométriques locales de manière directe. Dans le cas d'une distribution étendue, le comportement acoustique du milieu est gouverné par des tailles critiques qui sont déterminées à partir de la porosité et de la perméabilité statique pour une mousse à cellules ouvertes ; pour une mousse à cellules partiellement fermées il est nécessaire d'identifier en plus une dimension connue de la géométrie locale. Nos résultats sont comparés avec succès à des données expérimentales obtenues par des mesures au tube d'impédance. Dans une seconde étape, les propriétés élastiques effectives du milieu poreux sont déterminées. Une modélisation par éléments finis de la cellule représentative a été mise en œuvre. Les paramètres élastiques calculés sont finalement comparés avec les données de la littérature, ainsi qu'à des essais mécaniques / This work aims at determining the acoustical properties of poro-elastic media through a multi-scale method. Some imaging techniques (tomography and micrographs) allow to estimate some quantitative microstructure properties of foams containing open or partially closed cells. These properties are used in order to clarify the features of a representative three-dimensional unit cell of a periodic structure, which mimics the behaviour of the real foam. All parameters controlling the acoustical properties of the porous foam are obtained by using the homogenization of periodic structures. In a first step, the structure of the foam is assumed to be rigid. It was shown that, in the case of a narrow distribution of the characteristic size of the local geometry, a direct computation of the macroscopic behaviour from the local geometrical properties is consistent with the measured acoustical properties. For a wide distribution of pore size, the acoustical behaviour is controlled by critical sizes that are obtained from porosity and static permeability for an open-cell foam, while for partially closed cells, the identification of a complementary characteristic dimension within the pores becomes necessary (e.g. closure rate of membranes). Our results compare well with data obtained from an impedance tube set-up. In a second step, effective elastic properties are computed through a modelling of the foam structure by finite elements. The computed elastic parameters are finally compared with data coming from the literature and with results of mechanical tests

O presente trabalho tem como intuito o estudo da reciclagem química de espumas rígidas de poliuretano através do processo de glicólise em um reator de micro-ondas utilizando o dietilenoglicol como agente decompositor, além de avaliar as propriedades de reaplicação e desempenho mecânico da espuma reciclada frente a uma espuma padrão de mercado. Uma fase de estudos preliminares foi estabelecida para avaliação comparativa entre catalisadores, considerando no estudo o hidróxido de sódio, o dilaurato de dibutil estanho e a dietanolamina, onde o hidróxido de sódio se mostrou como sendo o catalisador mais interessante para o escopo do trabalho. Para estudo das melhores condições reacionais, foi elaborado um desenho de experimentos avaliando as faixas ótimas para temperatura e concentração de catalisador utilizados no processo da glicólise onde foi constatada a temperatura de 230 °C e concentração de catalisador de 0,68% como valores mais adequados para a reciclagem. Os produtos da glicólise foram analisados quanto ao seu espectro no infravermelho e ressonância magnética nuclear de carbono-13, além de serem avaliados em relação ao seu número de hidroxila, basicidade e viscosidade. O conteúdo de polióis base de uma formulação de espuma rígida foi substituído por diferentes porcentagens de poliol reciclado sua reatividade e propriedades mecânicas como resistência à compressão e estabilidade dimensional foram analisados apontando um bom desempenho para os padrões de reatividade e propriedades mecânicas em uma substituição de até 40% dos polióis virgens pelo reciclado. / The present work has studied the chemical recycling of polyurethane rigid foams through microwave assisted glycolysis process using the diethyleneglycol as decomposing agent, and evaluating the reapplication and performance of the recycled foams in comparison to a market standard rigid foam. A preliminary study was set up to evaluate and compare the performance of catalysts such as sodium hydroxide, dibutiltin dilaurate and diethanolamine, where the sodium hydroxide presented the best overall performance. A design of experiments was performed in order to evaluate the optimum values of the processing temperature and catalyst concentration, which resulted in 230 °C and 0,68% as the optimum conditions to temperature and catalyst concentration, respectively. The glycolysis products were analyzed via infrared spectroscopy and carbon-13 nuclear magnetic resonance and were also evaluated regarding their hydroxyl number, basicity and viscosity. The base polyols from a standard rigid foam formulation were replaced by different amounts of recycled polyol and the reactivity profile as well as the physical properties such as the compression resistance and dimensional stability of the new formulations were measured pointing out a good performance of the reactivity profile and physical properties of the formulations with polyol replacement up to 40%.

Os polímeros são usados em numerosas aplicações e em diferentes segmentos industriais, gerando enormes quantidades de rejeitos no meio ambiente. Entre os vários componentes de resíduos nos aterros sanitários estão os materiais poliméricos, entre eles o Polipropileno que contribuem com 20 a 30% do volume total de resíduos sólidos. Como os materiais poliméricos são imunes à degradação microbiana, permanecem no solo e nos aterros sanitários como um resíduo semipermanente. A preocupação ambiental no sentido de redução de resíduos se voltou para o desenvolvimento de polímeros renováveis para a fabricação de materiais que se decompõem na natureza, entre eles estão às espumas poliméricas biodegradáveis. Os polímeros espumados são considerados materiais do futuro, com um leque abrangente de aplicações; as espumas estruturais, de alta densidade, são usadas principalmente na construção civil, em substituição a metais, madeiras e concreto com a finalidade básica de reduzir custos com materiais. O objetivo deste trabalho foi a incorporação de blendas da matriz polimérica PP/HMSPP com bagaço de cana-de-açúcar, PHB e PLA, na produção de espumas estruturais. A degradação via tratamento térmico, nas temperaturas 100º, 120º e 160º C não foi suficiente para induzir a biodegradabilidade; já a degradação via irradiação gama, nas doses 50, 100, 150, 200 e 500 kGy se mostrou eficaz para indução da biodegradabilidade. As composições com bagaço, irradiadas, também sofreram deterioração superficial, favorecendo a absorção de água, e, consequentemente, uma maior biodegradação. / Polymers are used in various applications and in different industrial areas providing enormous quantities of wastes in environment. Among diverse components of residues in landfills are polymeric materials, including Polypropylene, which contribute with 20 to 30% of total volume of solid residues. As polymeric materials are immune to microbial degradation, they remain in soil and in landfills as a semi-permanent residue. Environmental concerning in litter reduction is being directed to renewable polymers development for manufacturing of polymeric foams. Foamed polymers are considered future materials, with a wide range of applications; high density structural foams are specially used in civil construction, in replacement of metals, woods and concrete with a final purpose of reducing materials costs. At present development, it was possible the incorporation of PP/HMSPP polymeric matrix blends with sugarcane bagasse, PHB and PLA, in structural foams production. Thermal degradation at 100, 120 and 160°C temperatures was not enough to induce biodegradability. Gamma irradiation degradation, at 50, 100, 150, 200 and 500 kGy showed effective for biodegradability induction. Irradiated bagasse blends suffered surface erosion, in favor of water uptake and consequently, a higher biodegradation in bulk structure.