New polyurethanes from oxypropylated olive stone

The purpose of this work is to explore the possibility of chemically modifying the generated polyols (oxypropylated olive stone) through reactions with isocyanates to produce polyurethanes, other than rigid polyurethane foams. This could be achieved by the chemical modification of the oxypropylation products (condensation with isocyanates) by using mono and difunctional reagents to modulate properties and/or produce useful polymer networks.FCT (project PTDC/CTM/71491/2006_FCOM- 01-0124-FEDER-007156

Search for novel biobased materials within the OLIVPOL project

Within the context of the project OLIVPOL, olive stone (OS) residue was successfully converted into viscous polyols, as such, or containing reinforcing stone cores, by total or partial oxypropylation, respectively. Moreover, the synthesis of new macromolecular materials using the oxypropylated products, such as polyesters and polyurethanes, demonstrated a promising approach to the production of original value-added products based on renewable resources.FCT (Project PTDC/CTM/71491/2006_FCOM-01-0124-FEDER-007156

Development of a prototype to access biodegradability of TPU shoe soles under controlled conditions

In the last years, the increasing problems posed by waste management have stimulated the interest in developing more sustainable and bio-based solutions for the footwear industry, including the use of biodegradable materials. As part of the NEWALK project, the objective of this work consisted in optimizing and implementing a respirometry system prototype. Besides evaluating different variables, two different approaches for measuring the evolved CO2 were assayed. Compared to manual titration, the use of conductivity offers the advantage of an automatic continuous monitoring.info:eu-repo/semantics/publishedVersio

The use of bio-based additives (lignin, starch and cellulose) in thermoplastic polyuretane formulations to enhance the biodegradability of footwear components

Thermoplastic polyurethanes (TPUs) are one of the most widely used polymeric materials. They can be used in an extensive range of applications, including automotive, footwear, interior design, adhesives, coatings, textile and biomedical. In what concerns the footwear sector, it is estimated that TPU based components represent about 60% of the whole European production of footwear components [1]. On the other hand, the use of a wide variety of additives in TPU formulations (e.g. pigments, coatings and fillers) limits the possibility of recycling. In such scenario, biodegradable polymers could offer an excellent solution to the environment hazard posed by the conventional materials [2]. Therefore, given the widespread use of TPUs and associated waste management problems, it makes sense to invest on the development of more biodegradable and environmental compatible solutions. For this purpose, the incorporation of bio-based and biodegradable additives is being studied in the last years [2-4]. The incorporation of a biodegradable compound, even at a low content in a TPU formulation, can promote biodegradation. It will constitute a preferential site for microorganisms’ attack thus favouring biodegradation initiation and progression. In this work, a base TPU used in the footwear industry was modified by compounding with three biobased additives (lignin, starch and cellulose). Biodegradability of the resulting materials was evaluated in agar plate tests against the fungi Aspergillus niger ATCC16404, the gram negative bacteria Pseudomonas aeruginosa ATCC9027 and an association of both (consortium). In a second phase soil tests have been also performed.info:eu-repo/semantics/publishedVersio

Screening of different microorganisms for their biodegradation capacity regarding polyester-based thermoplastic polyurethanes

and bio-based solutions in shoe manufacturing, including the use of biodegradable materials. As a first step towards the proposal of such solutions, in this work different microorganisms were screened for their intrinsic capacity to degrade a base TPU. The biodegradability was tested using the agar plate method against different bacteria, fungi and a consortium of both. The most promising results, corresponding to higher weight-loss percentages of the TPU sample, were obtained using the consortium of Pseudomonas aeruginosa and Aspergillus niger. These best conditions were thereafter applied to TPU samples compounded with biobased additives.info:eu-repo/semantics/publishedVersio

Materials, components and technology for the footwear of the future - Newalk project

At present, footwear is considered as one of the most internationalized sectors of the Portuguese industry with a significant importance for the national economy, as it is proved by the economic data of 2012: the average annual production was 74 million of shoe pares, being 90.0% of the production exported, which represents an average value of 1610 million euros [l].Financiai support from COMPETE, QREN and EU (project QREN SI J&D Copromoção 13850 NEWALK) and FCT and FEDER under Program COMPETE (PEst-C/EQB/LA0020/2011 strategic project).info:eu-repo/semantics/publishedVersio

NEWALK: novos materiais e componentes para calçado do futuro

A indústria do calçado é o núcleo de um importante cluster da economia nacional. A sua evolução refletiu-se no aumento da produtividade e no valor bruto da produção. Como resultado, o preço do calçado exportado em 2011 subiu para os 23,70 euros/par, tendo o valor global das exportações atingido 1548 milhões de euros (APICCAPS, 2012). Atualmente, este setor procura afirmar-se em nichos de mercado com maior exigência técnico-científica, de valor acrescentado e de padrões de qualidade elevados, resultando no investimento em investigação e desenvolvimento tecnológico. Neste contexto, o IPB tem participado em projetos de I&DT em parceria com o Centro Tecnológico do Calçado de Portugal (CTCP), estando presentemente em curso o projeto NEWALK

Modeling of phase equilibria of amino acids mixtures using the A-UNIFAC model

O combate ao aquecimento global, através da redução das emissões de gases com efeitos de estufa (GEE), a diversificação das fontes energéticas e a redução da sua dependência, a preocupação com a futura escassez ou aumento excessivo dos preços dos combustíveis de origem fóssil (petróleo), bem como a promoção do desenvolvimento rural constituem os principais objectivos que a UE pretende atingir com a substituição dos combustíveis convencionais pelos biocombustíveis. Os biocombustíveis líquidos, constituídos pelo bioetanol e biodiesel, representam uma boa alternativa aos combustíveis convencionais, uma vez que podem integrar-se facilmente nos actuais sistemas de distribuição e ser utilizados nos motores dos automóveis sem que estes tenham que sofrer grandes alterações na sua estrutura. Actualmente, os processos de produção de bioetanol produzidos à escala industrial utilizam matérias-primas de origem amilácea ou açucarada, originando um intenso debate sobre a sustentabilidade desta biomassa. Desta forma, o bioetanol produzido de biomassa lenhocelulósica representa uma alternativa viável, já que as matérias-primas se encontram amplamente distribuídas, não competem com o mercado alimentar e são mais baratas que os recursos agrícolas convencionais. A presente Tese de Mestrado visa estudar as diferentes etapas de produção de etanol a partir da palha de cevada. Com o intuito de modificar a estrutura da biomassa lenhocelulósica, para facilitar o acesso das enzimas na etapa de hidrólise enzimática, a matéria-prima foi pré-tratada utilizando um tratamento hidrotérmico designado Liquid Hot Water (LHW). O etanol foi obtido do resíduo sólido pré-tratado (RSI), mediante um processo de Sacarificação e Fermentação Simultâneas (SFS), utilizando a levedura Saccharomyces Cerevisiae. A melhor taxa de recuperação de glucose no resíduo sólido decorrente da aplicação do pré-tratamento de LHW foi de 91,71% tendo sido obtida para as condições de 185ºC, 10 minutos e 2% ácido acético. Não obstante, o teste de hidrólise enzimática (HE) com os RSI preparados para diferentes condições de processo apontou que o melhor rendimento de glucose (91,80%) é obtido para as condições de pré-tratamento de 195ºC, 10 minutos e 2% ácido acético. Estas duas condições foram utilizadas a uma escala superior (2L) tendo os RSI resultantes sido usados no processo de SFS. A concentração máxima de etanol (21,96 g/l) correspondente a um rendimento de 69,5% foi obtida com o RSI correspondente às condições 195ºC, 10 minutos e 2% ácido acético. The fight against global warming, by reducing the emission of greenhouse gases, the diversification of energy sources and reduction on its dependence, the apprehension concerning future scarcity or excessive increase in fossil fuels (petroleum) prices, as well as the promotion of rural development are the main objectives that EU wishes to achieve with the substitution of conventional fuels by biofuels. Liquid biofuels, i.e., bioethanol and biodiesel, constitute good alternatives to conventional fuels since they can be easily integrated into current fuel systems distribution and can be used in car engines without major changes in its structure. Nowadays, production of ethanol relies on bioethanol from starch and sugars; nevertheless a considerable debate on its sustainability is in focus. In this context, bioethanol produced from lignocellulosic biomass is an interesting alternative since these raw materials are much widely distributed, do not compete with food crops and are also less expensive than conventional agricultural feedstocks. The present Master Thesis addresses the study of the different stages involved in the ethanol production from barley straw. In order to promote structure modifications of lignocellulosic biomass, thus facilitating enzymes access in the enzymatic hydrolysis step, the raw material was pretreated with liquid hot water (LHW). Ethanol was produced from the obtained LHW solid residue (RSI) by means of a Simultaneous Saccharification and Fermentation (SSF) process, using the yeast Saccharomyces Cerevisiae. The maximum glucose recovery achieved in the solid residue from the LHW pretreatment was 91.71%, obtained by using the conditions of 185 ºC, 10 minutes and 2% acetic acid. Nevertheless, the enzymatic hydrolysis test (HE) with RSI prepared with different process conditions pointed out that the best yield of glucose (91.80%) is obtained by using 195 ºC, 10 minutes and 2% acetic acid. These two set of experimental conditions were further used at a higher scale level (2 L) and the resulting RSI used in the SFS process. The maximum achieved ethanol concentration (21.96 g/l) corresponding to a yield of 69.5%, resulted from the RSI obtained using 195 ºC, 10 minutes and 2% acetic acid

Chemical modification as a strategy to modulate properties of oxypropylated products

Nowadays a great interest is devoted to the production and use of biobased products. The main scope of the oxypropylation process is to obtain polyols, in the form of viscous liquids, which can be interesting co-monomers to produce polyurethanes and polyesters. Due to the high hydroxyl content of natural polymers (suitable substrates to be oxypropylated), the generated polyols are multifunctional, hence most adequate to be used in rigid polyurethane foam formulations. Additionally, their properties can be modulated through chemical modification, thus opening new avenues for their exploitation. Following that strategy, an oxypropylated product (IOH of 350) used as a model polyol, was modified by reacting it with a mixture containing phenyl isocyanate (PI) and toluene diisocyanate (TDI) at PI/TDI molar ratios of 100/0, 80/20, 50/50, 20/80 and 0/100. This chemical system was chosen in order to guarantee a homogeneous medium during the course of the reaction. Syntheses were performed in dichloromethane solution at room temperature under nitrogen, using DBTDL as catalyst, with a reaction time of 6 hours. Kinetics was followed by FTIR in transmittance mode using a liquid cell equipped with NaCl windows. For that purpose, sample aliquots were taken from the reaction medium at time intervals of 10 minutes during the first hour, 30 minutes during the second hour and at one hour intervals until the end of the reaction. After the established reaction time of 6 hours, residual isocyanates were neutralized with methanol and the final product purified, dried and characterized by FTIR and DSC.To FCT (project PTDC/CTM/71491/2006_FCOM-01-0124-FEDER-007156) and LSRE (strategic project PEst-C/EQB/LA0020/2011)

Biobased additives as biodegradability enhancers with application in TPU-based footwear components

Among the wide variety of materials employed in the manufacture of shoes, thermoplastic polyurethanes (TPUs) are one of the most widely used. Given its widespread use, and associated waste management problems, the development of more biodegradable and evironmentally compatible solutions is needed. In this work, a polyester-based TPU used in the footwear industry for outsoles production was modified by compounding with lignin, starch and cellulose at content of 4% (w/w). The biodegradability was evaluated by using agar plate tests with the fungi Aspergillus niger ATCC16404, the Gram-negative bacteria Pseudomonas aeruginosa ATCC9027 and an association of both (consortium), and soil tests at 37 °C and 58 °C. The obtained results evidenced a positive effect of the tested biobased additives, the most favourable results being registered with lignin. These results were corroborated by the structural modifications observed by FTIR analysis. Additionally, mechanical tests prove the suitability of using the lignin modified TPUs for footwear outsoles production