Selecting a polymer depends on its characteristics, the properties of the drug and of the remaining ingredients in the formulation. The drug, when incorporated into a polymeric matrix, can show several advantages when compared with its conventional form. In this context, this work describes the preparation and characterization of polyethylene glycol (PEG 4000) and its derivative particles loaded with benznidazole, as well as evaluates their trypanocidal activity. In this work, reactions to modify the PEG 4000 polymer and the subsequent incorporation of the benznidazole were made. The nuclear magnetic resonance (NMR) analysis confirmed the efficiency in modifying the PEG chains. The morphology of polymeric films was observed by atomic force microscopy (AFM) and showed considerable changes on the film organization. The acetylation of PEG favored the stability of the system and an increase in the zeta potential from ?14.83 to ?25.54 mV was observed. Although encapsulation efficiency values between 30.14 and 39.48% were found, the enhanced benznidazole dissolution profile by microparticles enables the use of lower drug concentrations. This fact can be proven by the increased trypanocidal effect of benznidazole when encapsulated in BP3 microparticles. Finally, the high selectivity of the formulations for trypanocidal action guarantees their safety as an alternative for the treatment of the Chagas disease.

Abstract This article seeks to characterize the seed husk fiber of Moringa oleifera and understand its influence when added to a cementitious composite, in terms of mechanical performance. Moringa fibers were chemically and physically tested and were added to a cementitious composite. Specimens were molded for Ultrasonic Speed Pulse test and Uniaxial Compression Strength test, and subsequent observation in SEM. The results show a fiber with high lignin content and high absorption of water. Adding fiber to the composite, the water in the mixture is absorbed, which reduces the formation of hydrated cement compounds over time. Consequently, it results in a composite with low mechanical strength. The fiber/matrix interface analyzed in the micrographs is porous, has microcracks and a high concentration of calcium hydroxide. Despite this, the same lignin content that impairs mechanical strength in this composite is what makes the fiber resistant to weathering. More studies regarding the effectiveness of this quality should be carried out.

The insertion of functional groups in polymer compounds may facilitate their interaction with different drugs. PEG polymers are widely used for their low melting point, low toxicity, drug compatibility, and hydrophilicity. They are used as pharmaceutical excipients for the formulation of conventional or modified released drugs and are designed to be upgraded as drug-modulating controllers at specific sites in the body. Indomethacin has been used in the controlled release of drugs because it is a drug that have good interaction with different polymers. The drug is a non-steroidal anti-inflammatory drug used in the treatment of rheumatoid arthritis, osteoarthritis, spondylitis, and other disorders. In this work, PEG 4000 had its chain modified by organic reactions and their derivatives were emulsified to form microparticles using polyvinyl alcohol as an emulsifier. Posteriorly were also incorporated with indomethacin. The samples were characterized to prove the influence of indomethacin on the morphology and thermal behavior of this polymer. The controlled release was performed in the time from 0 to 240 min using the Ultraviolet Spectroscopy to quantify indomethacin released from the polymer matrix for these 4 hours. Releases over the time were satisfactory as concentrations increased over time, which we can conclude that the structural modification of PEG 4000 was beneficial in the release of the indomethacin drug.

Abstract The injection of pulverized materials is a technique used in most of the blast furnaces in the world to reduce coke and charcoal consumption. In addition, injection is one of the main variables of the blast furnace heat control. Coal is the most used material for the injection, but some industries have been attempting to use other materials, usually mixtures, in order to reduce the total dependence on it. The quality of the injected material influences some operational parameters, such as the permeability, the heat control, and also the quality of the hot metal produced. Due to these factors, the strategy and quality of these materials should be planned and evaluated using quality indicators to achieve good production, with low cost and environmental impact. In this context, there is a large number of researches on different materials, especially waste from iron and steelmaking processes, among others. Herein, some quality indicators of different materials tested on industrial and laboratory scales were analyzed compared, and the feasibility of using new materials injected into the blast furnace was discussed.

Abstract There are few studies about Moringa oleifera derivates in polymer developments where vegetable oil was used as a plasticizer and a biodegrading agent. The polymerization of moringa oil (MO) was carried out assisted by microwaves without catalysts presence. There aren’t studies about the polymerization of MO using microwaves technology. Moringa’s oil and its polymer (PMO) were used as a biodegrading agent for mixtures of low density polyethylene (LDPE) with poly(butylene adipate-co-terephthalate)/poly(lactic acid) (PBAT/PLA). The mixtures producted films that were characterized and submitted to biodegradation analysis in order to discuss the influence of moringa components. Results showed that both moringa components improved thermal properties and reduced the crystalline phase of the mixture. The addition of PMO had improved the biodegradation capacity up to five times while MO had improved it up to three times. The results showed the greatest influence of moringa components on biodegradation of mixtures with cited polymers.

Resumo O rápido desenvolvimento da química de polímeros nos últimos anos tem acompanhado a introdução dos materiais poliméricos no campo da medicina. Polímeros com aplicações médicas podem ser subdivididos em dois grandes grupos: materiais usados em próteses e a produção de polímeros biologicamente ativos. Neste trabalho foram sintetizados copolímeros possuindo cadeia principal de poli (metacrilato de metila) e cadeias enxertadas de polietilenoglicol (COP GRAFT). A partir da síntese do copolímero enxertado inicial foram realizadas modificações em suas cadeias de modo a aumentar a possibilidade de incorporação de um fármaco que será utilizado em sistema de liberação controlada de medicamentos. Os novos compostos foram obtidos através de duas rotas sintéticas e os produtos formados ao final de cada etapa foram purificados e caracterizados. Através da técnica de infravermelho (FITIR) foi possível observar as bandas de absorções características das ligações P-H, P=O e P-O, que foram inseridas na cadeia do COP GRAFT durante a fosforilação, além das bandas de absorções características do copolímero, antes da fosforilação, como C=O e C-O. A caracterização térmica das amostras utilizando termogravimetria (TGA) e calorimetria diferencial de varredura (DSC) mostrou que apenas o copolímero de diisobutila apresentou temperatura de transição endotérmica e comportamentos de degradação compatíveis a de um polímero. Através da técnica de difração de raios X (XRD) foi possível observar uma modificação da cristalinidade das amostras, provavelmente devido a uma variação da conformação das cadeias após a inserção de novos grupos químicos. Nos cromatogramas obtidos pela técnica de cromatografia de permeação em gel (GPC) percebeu-se aumento de massa após a fosforilação com o grupo diisobutila no COPGRAFT. A reação de fosforilação foi eficiente na obtenção do copolímero de diisobutila e as técnicas aplicadas demonstraram que houve a modificação no copolímero enxertado.

Abstract The rapid development in polymer chemistry has, in recent years, led to the introduction of polymeric materials in the field of medicine. Two major groups of polymers are used for medical applications: prosthetic and biologically active materials. We synthesized copolymers with the main chain consisting of poly (methyl methacrylate) and graft chains of poly(ethylene glycol) (COP GRAFT). Changes were made in the graft copolymer chains for a possible incorporation of a drug, such that it may be used for the controlled release of drugs. The synthesis of these new compounds is based on two synthetic routes and FTIR, differential scanning calorimetry (DSC), thermogravimetry (TGA) and X-ray diffraction (XRD) characterized the products formed at the end of each stage. Through FTIR we observed absorption bands characteristic of P-H, P=O and P-O bonds that were inserted into the polymer chain during phosphorylation of the COP GRAFT, beyond the absorption bands characteristic of the copolymer before phosphorylation, such as C=O and C-O. By TGA and DSC we observed that only the diisobutyl copolymer has endothermic transition temperature and degradation behavior consistent with a polymer. XRD results showed a structural and conformational change in crystallinity of modified chains. Molecular weight and polydispersity of COPGRAFT obtained by GPC increased after phosphorylation with diisobutyl group. The phosphorylation reaction was efficient in obtaining diisobutyl copolymer and the applied techniques confirmed the modification of the COPGRAFT chains.

Nowadays the interest in polymeric composites reinforced with vegetal natural fibers in substitution for manufactured fibers is increasing. This is due to the fact that vegetal fibers are less abrasive, biodegradable, present low density and excellent mechanical and thermal properties. Several vegetal fibers have been used for various types of composites among which the bamboo differs from these fibers in being widely used for cellulose and paper industrial production. This paper presents the results of recent researches about fiber and pulps of bamboo, which were submitted to several types of tests, aiming at a better understanding of their properties. The main objective of this study was to physical-chemical characterize fiber and bamboo pulps, disseminating their properties and maximizing their use in polymeric applications. Most of the samples were analyzed and characterized using the methods recommended by the American Society for Testing and Materials, ASTM and the Technical Association of the Pulp and Paper Industry, TAPPI. The results show that the refined pulp was more suitable to be used as a reinforcing agent in polimeric composites instead of the unrefined pulp and natural fiber.

Atualmente é crescente o interesse pelos compósitos poliméricos reforçados com fibras naturais vegetais em substituição às fibras manufaturadas. Isto se deve ao fato das fibras vegetais serem menos abrasivas, biodegradáveis, apresentar baixa densidade e excelentes propriedades mecânicas e térmicas. Várias fibras vegetais vêm sendo utilizadas nos mais variados tipos de compósitos, dentre as quais as de bambu se diferenciam por serem largamente utilizadas na produção industrial de celulose e papel. Este trabalho apresenta os resultados de recentes pesquisas envolvendo fibra e polpas de bambu, as quais foram submetidas a vários tipos de ensaios, visando um maior conhecimento de suas propriedades. O principal objetivo deste estudo foi caracterizar físico-quimicamente fibra e polpas, difundindo suas propriedades e maximizando sua utilização em aplicações poliméricas. Grande parte das amostras foram analisadas e caracterizadas utilizando as metodologias preconizadas pela American Society for Testing and Materials, ASTM e pela Technical Association of the Pulp and Paper Industry, TAPPI. Os resultados mostram que a polpa refinada se apresentou mais adequada para ser utilizada como agente de reforço em compósitos poliméricos em detrimento da polpa sem refino e fibra natural.

The aim of this work was to evaluate the oil extracted from Moringa oleifera (fam. Moringaceae) seeds from the nutritional standpoint. Nutritional evaluation of crude or degummed moringa oil or soybean oil (as a control) involved the determination of the Food Efficiency (FE) in male Fisher rats and the fatty acid composition of the moringa oil. Hepatic and renal functions were assessed by measuring serum transaminases activity and urea and creatinine concentrations, respectively. Serum cholesterol and triglycerides, alkaline phosphatase, total proteins and albumine were also measured. Results showed that FE was slightly increased by the crude moringa oil while no differences were found between the soybean and degummed moringa oil regarding this parameter. Renal or hepatic injures as well as major alterations in serum proteins were not induced by the tested oils. These results suggested that degummed M. oleifera oil possessed adequate biological quality as compared to the crude oil.

Uma série de copolímeros com segmentos líquido-cristalinos foram sintetizados por policondensação em solução a alta temperatura e misturados com poli(tereftalato de etileno) (PET) e um poliéster líquido-cristalino termotrópico (TLCP), previamente sintetizado. Os copolímeros foram utilizados com sucesso como compatibilizantes nas misturas PET/TLCP. As técnicas de caloria diferencial de varredura, análises dinâmico-mecânicas, análises térmicas e microscopia eletrônica (SEM) foram utilizadas na caracterização dos polímeros. Foi verificada boa processabilidade e diminuição da velocidade de cristalização das misturas. As micrografias das superfícies fraturadas das amostras, obtidas das análises de SEM, mostraram melhor miscibilidade para as misturas com maior teor de copolímero.

A serie of copolyesters with liquid crystalline segments were synthesized by high temperature solution polycondensation and mixed with poly(ethylene terephthalate) (PET) and a thermotropic liquid crystalline polyester (TLCP), previously synthesized. The copolyesters were successfully applied to compatibilize PET/TLCP blends. The techniques applied to characterize compatibilization were thermal analysis, differential scanning calorimetry, dynamic mechanical analysis and eletron microscopy (SEM). Good processing and depression of crystallization rate were obtained in blends. The SEM micrographs for fractured surface show better miscibility from PET/TLCP blends with higher content of copolymer.

Foi realizado o estudo cinético da cristalização dinâmica de um poliéster líquido-cristalino termotrópico com espaçadores flexíveis na cadeia principal. O objetivo deste estudo foi verificar o mecanismo da cinética de cristalização do poliéster termotrópico semi-flexível através de um método não-isotérmico. O método empregado (método de Ozawa) permitiu descrever a cinética de cristalização dinâmica do poliéster e os valores de n (expoente de Avrami) encontrados correspondem a um crescimento de cristais em forma de feixe sem crescimento esferulítico posterior.

The study of dynamic crystallization kinetics of a thermotropic polyester with flexible spacers in the main chain was done. The aim of this study was to verify the crystallization kinetics mechanism of a thermotropic semi-flexible polyester by a dynamic method. The selected method (Ozawa method) has allowed to describe the crystallization kinetics and the values of n (Avrami exponent) correspond to sheaf-like aggregation without further growing into spherulites.