THAIS NEVES FONSECA
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Resumo IPEN-doc 26959 Study of Bixin oxidation by ionizing irradiation2017 - FONSECA, THAIS N.; MOURA, EDUARDO de; GERALDO, AUREA B.C.Brazil is the world's largest producer of annatto, followed by Kenya and Peru (CORLETT, 2007). The fruit of the annatto tree is constituted by a capsule containing external spines and internal seeds with reddish coloration, providing a natural pigment which is environmentally efficient, being able to replace synthetic pigments and dyes. The active substance of the pigment is Bixin, which is a type of carotenoid which constit utes a greater percentage of pigment in these seeds and has a lipo soluble character ( CUSTODIO , 2002 ). Bixin reacts with NaOH in a saponification reaction giving norbixin, which is water soluble. It is known that the destination of the dye extracted from t he fruit is intended for industry, especially the food industry. The culture of annatto tree brings prospects of development of agricultural programs for medium and small producers, which are able to use decadent areas of other crops. In addition to the fo od sector, new applications for the pigment helps the development of family farming (BERTOLIN, 2016). The pigment extracted from annatto undergoes a natural oxidation; this work aims to evaluate this phenomenon and also the oxidation of the pigment after the irradiation process. This work also evaluates of the how the oxidation process is affected by irradiation and the modifications introduced to irradiated pigments. Irradiated and non irradiated samples were characterized by UV vis s pectrophotometry a nd infrared spectroscopy (FTIR). The results are then discussed.Resumo IPEN-doc 24124 Estudo da oxidação da bixina por irradiação e aplicação em materiais resinosos2017 - FONSECA, THAIS N.; MOURA, EDUARDO de; GERALDO, AUREA B.C.Artigo IPEN-doc 24187 Study of bixin oxidation by ionizing irradiation2017 - FONSECA, THAIS N.; TEIXEIRA, PAULA S.; MOURA, EDUARDO de; GERALDO, AUREA B.C.Brazil is the world's largest producer of anatto, followed by Kenya and Peru. The fruit of the annatto tree is constituted by a capsule containing external spines and internal seeds with reddish coloration, providing a natural pigment which is environmentally efficient, being able to replace synthetic pigments and dyes. The active substance of the pigment is Bixin, which is a type of carotenoid which constitutes a greater percentage of pigment in these seeds and has a lipo soluble character. Bixin reacts with NaOH in a saponification reaction giving norbixin, which is water soluble. It is known that the destination of the dye extracted from the fruit is intended for industry, especially the food industry. The culture of annatto tree brings prospects of development in agricultural programs for medium and small producers, which are able to use decadent areas of other crops. In addition to the food sector, new applications for the pigment helps the development of family farming. The pigment extracted from annatto undergoes a natural oxidation; this work aims to evaluate this phenomenon and also the oxidation of the pigment after the irradiation process. This work also evaluates of the how the oxidation process is affected by irradiation and the modifications introduced to irradiated pigments. Irradiated and nonirradiated samples were characterized by thermogravimetry, UV-vis spectrophotometry and infrared spectroscopy (FTIR). The results are then discussed.Artigo IPEN-doc 24179 Irradiação da biomassa lignocelulósica de sementes de urucum (Bixa orellana L.) para aplicações em compósitos poliméricos2017 - TEIXEIRA, PAULA S.; FONSECA, THAIS N.; MOURA, EDUARDO de; GERALDO, AUREA B.C.O estudo de compósitos poliméricos reforçados com fibras vegetais tem se tornado popular nas últimas décadas já que este tipo de material possibilita a redução tanto do rejeito de biomassa como o custo final do produto polimérico. Fibras vegetais existem em grande quantidade, são de baixo custo e conjugam biodegradabilidade e renovação. Além disso compósitos de polímero-celulose são mais resistentes à flexão e ao impacto que o mesmo material exclusivamente feito em polímero. Especificamente a celulose contida nas sementes de urucum está presente em uma concentração em torno de 40-45 %, o qual torna-se importante para o uso industrial. Neste trabalho, o bagaço das sementes de urucum após a remoção do seu pigmento avermelhado foi usado para obter compósitos de polietileno de alta densidade (PEAD). O material original foi usado sem e com um prétratamento que removeu componentes como o resíduo do pigmento remanescente, açúcares, proteínas e ácidos graxos. As fibras remanescentes foram secas, fragmentadas e submetidas à irradiação por feixe de elétrons nas doses de 10 kGy, 25 kGy, 50 kGy e 75 kGy para verificar o efeito da radiação na estrutura da celulose e seu subsequente efeito na matriz polimérica.