The development of both versatile and inexpensive sorbents for CO2/CH4 separation has become one of the greatest challenges to the environment and natural gas processing. This study reports the preparation and characterization of polyurethane (PU)/ cellulose based poly(ionic liquid)(CPIL) composites for CO2/CH4 separation. PU matrix was reinforced with CPIL in the range of 10-30 wt%. Several characterization techniques (TGA, DSC, DMTA and FESEM ) were used to study the physical properties of composites when the PU matrix is reinforced with cellulose based poly (ionic liquids) (CPIL) up to 30%. CO2 sorption, reusability and CO2/CH4 selectivity were assessed by pressure-decay technique. Results showed that CPIL addition in PU matrix promoted the increase in both thermal stability and mechanical properties when compared to PU. The best result for CO2 sorption (35.0 mgCO2/g) was obtained for PU/CPIL-TBP 10% which presented a higher sorption value when compared to PU (24.1 mgCO2/g) and PU/CELLULOSE 10% (26.8 mgCO2/g). PU/CPIL-TBP 20% demonstrated higher CO2/CH4 selectivity. PU/CPIL composites appear as promissory materials for CO2 capture. These compounds combine the benefits of ionic liquids (ILs) (high ionic conductivity, chemical and thermal stability) and cellulose (thermal stability) with PU properties (mechanical stability, processing and tunable macromolecular design).

Capturing carbon dioxide (CO2) from exhaust gases is an important strategy to prevent climate change. There is a great interest in developing novel CO2 sorbents. Thus, a series of polyurethane (PU) / silica xerogels functionalized with RTILs (bmim Cl and bmim TF2N) composites were prepared and characterized. PU matrix was reinforced with functionalized silica xerogels in the range of 0.5-20 wt%. PU / functionalized silica xerogels were characterized by NMR, FTIR, DSC, TGA, DMTA and FESEM. CO2 sorption capacity and reusability were assessed by the pressure-decay technique at 298.15 K and 1 bar. Results showed that the filler aggregation in PU matrix promoted the reduction of mechanical properties. However, addition of silica xerogels functionalized with RTILs in PU matrix led to increased CO2 uptake. CO2 sorption capacity tends to increase with the incorporation of silica xerogels functionalized with RTILs in PU matrix. The best CO2 sorption value was found for PU/SX-[Bmim]-[TF2N] 0.5 composite (48.5 mgCO2/g at 298.15 K and 1 bar). Moreover, the PU/SX-[Bmim]-[TF2N] 0.5 composite showed reuse capacity and higher CO2 sorption value as compared to other reported composites.

The development of polyester based materials with enhanced properties as well as the use of post- consumer plastics as raw material has been an increasing market demand. This work aims the synthesis and characterization of aromatic polyesters/titanium dioxide nanocomposites from PET and using TiO2 (0, 1, 3 and 5% w/w) as filler by in situ polymerization. The results obtained by DSC, XRD and FTIR analyzes evidenced an interaction between the OH groups on the TiO2 surface with the ester groups of the polymer leading to decrease of the polymer crystallinity and of hydrophilicity. By SEM images was possible to note a homogeneous distribution of the filler into polymer matrix with 1%w/w TiO2 (average particle size of 199 nm), however for larger amounts of filler (3 and 5% TiO2) revealed the aggregates formation. The results showed an improvement of thermal properties and hardness of the nanocomposites containing TiO2 nanoparticles compared to pristine polyester.

O objetivo deste trabalho foi avaliar a diversidade genética de acessos de cacau, selecionados previamente como produtivos e resistentes à vassoura-de-bruxa na Bahia, e estudar suas inter-relações com genótipos no banco de germoplasma. Amostras de DNA de folhas dos 120 acessos, coletados em 17 fazendas de sete municípios do Sul da Bahia, foram amplificadas pela técnica de RAPD ("random amplified polymorphic DNA"). Os coeficientes de dissimilaridade genética, calculados pelo método de Jaccard a partir das bandas RAPD, permitiram evidenciar, pela análise de agrupamento, que a maioria das seleções das fazendas (89,2%) agrupou-se com acessos do banco de germoplasma considerados representativos da diversidade de cacau (híbridos, trinitários, Scavinas, amazônicos e cacau-comum). As demais seleções distribuíram-se em outros sete grupos distintos. Há elevada diversidade genética entre as seleções das fazendas, e algumas delas devem ter-se originado de genitores não incluídos nesta análise. Esses materiais apresentam potencial para seleção de clones com maior diversidade para novos cruzamentos ou uso pelos agricultores.

The objective of this work was to assess genetic diversity of farm cacao accessions, previously selected as productive and resistant to witch broom in Bahia, Brazil, and to study their interrelationship with reference genotypes on germplasm bank. DNA samples from 120 cacao accessions, collected on 17 farms in seven counties in Southern Bahia, were amplified by RAPD technique (random amplified polymorphic DNA). The coefficients of genetic dissimilarity, calculated from the RAPD bands by Jaccard method, allowed to show by cluster analysis that most farm selections (89.2%) grouped with accessions from germplasm bank considered representatives of the cacao genetic diversity (hybrids, Trinitarian, Scavina, Amazon and common cacao). The other selections were distributed in seven distinct groups. There is high genetic diversity among farm selections, and some of them may have originated from other progenitors not included in this analysis. These materials present potential for clone selection with higher diversity for new crossings or direct use by agriculturists.