Valorização da casca do pinhão, um subproduto da semente de Araucaria angustifolia, para produção de materiais poliméricos
The valorisation of agro-forestry residues, namely the ones which do not have commercial value, have attracted the interest of academia and industrials contributing to generate new alternatives in the field of chemicals, materials and energy. The purpose is not only to promote their reuse to generat...
| Autor principal: | Rezende, Stephany Cunha de |
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| Formato: | Trabalho de Conclusão de Curso (Graduação) |
| Idioma: | Português |
| Publicado em: |
Universidade Tecnológica Federal do Paraná
2020
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| Assuntos: | |
| Acesso em linha: |
http://repositorio.utfpr.edu.br/jspui/handle/1/12631 |
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| Resumo: |
The valorisation of agro-forestry residues, namely the ones which do not have commercial value, have attracted the interest of academia and industrials contributing to generate new alternatives in the field of chemicals, materials and energy. The purpose is not only to promote their reuse to generate new value-added products, but also to highlight the production of bio-based products from renewable resources. This is a hot topic for several industrial sectors, namely the agroindustry, where the circular economy is an important factor towards sustainability. In circular economy it is expected that, in a near future, all the wasted products can gain a second life, resulting in both environmental and economic benefits. Araucaria angustifolia is a coniferous tree native of south america, found in the south and southwest of brazil, part of a whole vegetation of the atlantic forest whose seed is known as the brazilian pine-fruit. As a result of brazilian pine-fruit consumption, pine-fruit shell, a lignocellulosic residue with potential to be used as a raw material to produce polymeric materials is generated. In this context, this work comprises the characterization of pine-fruit shell and their subsequent use to produce polyols trough an oxypropylation process. Two different alternatives have been followed: (i) total oxypropylation to produce liquid polyols and (ii) partial oxypropylation to produce biphasic polyols (liquid polyols reinforced with biomass of the same nature). The first polyols were characterized and their properties compared with equivalent products to draw some of possible applications. The second ones were tested to produce composite materials by hot pressing. The pine-fruit shell was characterized in relation to the ash content and moisture, 1.7 and 5.0%, respectively, and lignocellulose content, which was obtained values of 26.9% cellulose, 13.8% hemicellulose, 40.7% of holocellulose (cellulose and hemicellulose), 34.6% insoluble lignin and soluble lignin 0.4%. Moreover, for extractable, the shell presented 5.9% in the extraction with methanol and 6.9% in the extraction with water, indicating majority amounts of hydroxylated substances and polar components compared with nonpolar components (extraction with hexane and dichloromethane). The oxypropylation was conducted in a pressure reactor equipped with a controller for monitoring temperature, pressure and stirring speed. The set point (target value to which the system is heated) was 160 °c, and 12 polyols containing unreacted Pine-fruit shell residues between 3.6-77.4%, an homopolymer content ranging from 4.4- 64.5% and an hydroxyl index comprised between 258.2-607.1 mg koh/g, were produced. Regarding the viscosity, polyols having low pine-fruit shell/propylene oxide (cp/op) ratios (10/90) had viscosities below of 5.0 pa.s at 20 °c. The partial oxypropylation was fulfilled with set point of 135 and 150 °c, using different cp/op ratios, with koh contents of 5 and 10%. The assays with a cp/op ratio of 33.3/66.7 (m/v) using a set point of 135 °c resulted in compact materials, with good proportions of oxypropylated material and binding between the parts. The assays with a cp/op ratio of 25/75 (w/v), also with set point of 135 °c, showed the best binding characteristics and proportions of oxypropylated material/non oxypropylated material representing suitable conditions for the partial oxypropylation reaction having in view incorporation into composite materials. |
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