Aliphatic Polyesters
Mostrando 1-10 de 10 artigos, teses e dissertações.
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1. The influence of soil and landfill leachate microorganisms in the degradation of PVC/PCL films cast from DMF
While the use of plastics continues to increase in our daily lives in a growing range products, these materials are very persistent in the environment. The blending of aliphatic polyesters with other thermoplastic polymers is a profitable way of producing materials with changed physical properties and biodegradability, which can facilitate microbial adhesion
Polímeros. Publicado em: 05/06/2012
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2. Polyol-polyesther matrices containing phthalocyanine derivatives macrocilces / Derivados de ftalocianina em sistemas poliméricos poliéster-poliol
Phthalocyanines are planar macrocycles with the presence of a central metal ion, formed by bridges of nitrogen and substituent groups in the aromatic rings adjacents. A large number of (PI) electrons, molecular symmetry and the possibility to coordinate different metals in nitrogen central atoms allows the use of these compounds in optical devices, light emi
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 06/05/2010
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3. Study on biodegradable aromatic/aliphatic copolyesters
Progress on biodegradable aromatic/aliphatic copolyesters based on aliphatic and aromatic diacids, diols and ester monomers was reviewed. The aromatic/aliphatic copolyesters combined excellent mechanical properties with biodegradability. Physical properties and biodegradability of copolyesters varied with chain length of the aliphatic polyester segment and a
Brazilian Journal of Chemical Engineering. Publicado em: 2008-06
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4. Synthesis and characterization of aliphatic polyesters from glycerol, by-product of biodiesel production, and adipic acid
In the present work, polyesters were prepared from the polycondensation between glycerol and adipic acid using dibutyltin dilaurate as catalyst. Three glycerol: adipic acid molar ratio were used for the bulk polymerization namely: 2:2; 2:3 and 2:4. FTIR confirmed the esterification of glycerol by the acid for all the polymers. DSC and XRD indicated no crysta
Materials Research. Publicado em: 2007-12
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5. Confecção de filmes biodegradáveis por extrusão de blendas de amido termoplástico e polibutileno succinato co-adipato (PBSA)
Blending high cost biodegradable synthetic aliphatic polyesters with low cost agropolymers, such as starch, is one of the alternatives for the production of biodegradable films. The objective of this work was to develop and characterize a biodegradable film based on thermoplastic starch (TPS) and polybutylene succinate co-adipate (PBSA), by film blow extrusi
Publicado em: 2007
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6. Caracterização espectroscópica e cromatrográfica de copoliésteres biodegradáveis
The recycling of poly(ethylene terephthalate) (PET) can be carried through by different techniques, one of them is the chemical recycling, where new aliphatic-aromatic copolymers are synthesized from melt reaction of the PET post-consumer with aliphatic homopolymers. The aliphatic polyesters, such as the poly(ethylene adipate) (PEA) are biodegradable. The sy
Publicado em: 2005
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7. Sintese, caracterização e biodegradação de um poliester-uretano
Anualmente, são produzidas cerca de 110 milhões de toneladas de plásticos no mundo, e pelo menos a metade desta quantidade é rapidamente descartada sem qualquer cuidado, permanecendo em aterros e na natureza por décadas, gerando um custo ambiental muito alto. Na tentativa de minimizar este problema, muitos cientistas passaram a investir em pesquisas na
Publicado em: 2003
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8. Phylogenetic Affiliation of Soil Bacteria That Degrade Aliphatic Polyesters Available Commercially as Biodegradable Plastics
Thirty-nine morphologically different soil bacteria capable of degrading poly(β-hydroxyalkanoate), poly(ɛ-caprolactone), poly(hexamethylene carbonate), or poly(tetramethylene succinate) were isolated. Their phylogenetic positions were determined by 16S ribosomal DNA sequencing, and all of them fell into the classes Firmicutes and Proteobacteria. Determinat
American Society for Microbiology.
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9. Biodegradation of Aliphatic-Aromatic Copolyesters by Thermomonospora fusca and Other Thermophilic Compost Isolates
Random aliphatic-aromatic copolyesters synthesized from 1,4-butanediol, adipic acid, and terephthalic acid (BTA) have excellent thermal and mechanical properties and are biodegradable by mixed cultures (e.g., in compost). Over 20 BTA-degrading strains were isolated by using compost as a microbial source. Among these microorganisms, thermophilic actinomycetes
American Society for Microbiology.
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10. Structural biopolymer preservation in Miocene leaf fossils from the Clarkia site, northern Idaho.
The 17- to 20-million-year-old locality at Clarkia, northern Idaho, is renowned for yielding amplifiable DNA from a magnolia leaf fossil. In-source pyrolysis-mass spectrometry and pyrolysis-gas chromatography/mass spectrometry now reveal that molecular preservation of biomacromolecules is highly selective; structural polysaccharides, cutin polyesters, and pr