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Extra??o, caracteriza??o e aplica??o do corante de urucum (Bixa orellana L.) no tingimento de fibras naturaisVer?ssimo, Silvagner Adolpho 10 April 2003 (has links)
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Previous issue date: 2003-04-10 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The increasing demand for natural dyes in place of synthetic ones is justified by the non-toxicity or low toxicity of the former. The synthetic dyes are associated with diseases like cancer as well as when released in the environment takes longer to degrade and the intermediates could be still more toxic. The Annatto (Bixa Orellana L.) is a carotenoid and one of the more important natural dyes used in the food industry. In the form of dye, it represents nearly 70% of the world natural dye production and 90% in Brazil. In the present work, annatto seeds were used of the species peruana paulista, which had nearly 2.1% of bixin. The process of dye extraction with ethyl alcohol showed 4% of dye in the form of powder with particle diameter of 28mm. The extraction process did not alter the chemical composition of the dye, which was confirmed by the electronic spectrum of absorption. Dyeings were carried out with different mordents to study the total colour difference as well as the wash fastness properties and friction fastness properties under wet and dry conditions. The samples treated with copper sulphate showed colour difference but at the same time showed better fastness results. The samples treated with resin (no formaldehyde) did not alter the colour significantly still better the fastness properties. From the results, it could be stated that the resin could be an alternative for heavy metallic mordents / A crescente demanda dos corantes naturais em detrimento dos sint?ticos ? justificada pela inocuidade e/ou baixa toxidade que os primeiros apresentam, uma vez que os corantes sint?ticos est?o associados ao surgimento de doen?as como o c?ncer, e quando descartados no meio ambiente al?m de necessitar de um longo per?odo para degradar os seus intermedi?rios podem ser ainda mais t?xicos. O urucum (Bixa orellana L.), um caroten?ide, ? um dos mais importantes corantes naturais usados na ind?stria de alimentos. Em volume, na forma de corante, representa cerca de 90% dos corantes naturais usados no Brasil e 70% dos corantes naturais usados no mundo. Neste trabalho foram utilizadas sementes de urucum da cultivar peruana paulista, que apresentaram 2,1% de bixina. O processo de extra??o com ?lcool et?lico mostrou um rendimento de 4% de corante em p?, cujo di?metro m?dio das part?culas foi de 28mm. O processo de extra??o n?o alterou a estrutura molecular do corante, comprovado pelo seu espectro eletr?nico de absor??o. Foram utilizados v?rios produtos no processo de tingimento de tecido de algod?o objetivando um estudo da diferen?a total de cor, como tamb?m melhoria dos ?ndices de solidez a lavagem e fric??o seco/?mido. As amostras tratadas com sulfato de cobre revelaram altera??o de cor, mas por outro lado apresentaram os melhores ?ndices de solidez. As amostras tratadas com resina (isenta de formaldeido) n?o alteraram significativamente a cor e ainda melhoraram razoavelmente os ?ndices de solidez. A resina reactante pode ser uma boa alternativa para substituir os mordentes met?licos, que possuem metal pesado em sua estrutura
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Obten??o de nanocelulose por hidr?lise ?cida e enzim?tica de fibras de algod?o de res?duo de tecido tingido com corante ?ndigoCruz, Luciani Paola Rocha 21 August 2017 (has links)
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Previous issue date: 2017-08-21 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Nanocristais de celulose s?o nanoestruturas derivados da celulose, que ? um recurso renov?vel
e abundante na natureza. Por apresentarem uma combina??o de propriedades como
alta resist?ncia mec?nica e m?dulo de elasticidade, superf?cie reativa e biodegradabilidade,
esses materiais t?m recebido grande interesse para aplica??es que incluem desde refor?o
em materiais polim?ricos, embalagens alimentares, a aplica??es na ?rea farmac?utica. A
produ??o de celulose nanom?trica a partir de fibras de algod?o tem sido relatada em v?rios
trabalhos publicados na literatura. O objetivo desta pesquisa foi estudar a obten??o de
nanocelulose a partir do res?duo de tecido de fibra de algod?o tingido com corante ?ndigo,
devido possuir alto conte?do de celulose, pelas vias de hidr?lise ?cida e enzim?tica. Nanocelulose
foi obtida com e sem a realiza??o de pr?-tratamento para remo??o do corante
e os efeitos do pr?-tratamento nas caracter?sticas da nanocelulose foram avaliados. Na
hidr?lise ?cida, foram avaliadas duas condi??es de tratamento para isolamento de nanocristais
de celulose: concentra??es de ?cido sulf?rico de 55% m/m a 60 C ou 65% m/m a
45 C, com tempos de 30 e 60 min. Na hidr?lise enzim?tica foram estudadas as influ?ncias
do tipo de complexo enzim?tico (Trichoderma reesei ATCC 26921 ou Aspergillus fumigatus),
o tempo (0 a 48h) e a carga enzim?tica (7,5 ou 12 FPU). As suspens?es obtidas
ap?s hidr?lise foram caracterizadas pelas t?cnicas de potencial zeta, microscopia de for?a
at?mica, microscopia eletr?nica de transmiss?o, espectrofotometria de infravermelho, difra??o
de raios X, an?lise termogravim?trica, a??cares redutores totais e cromatografia
l?quida de alto desempenho. Os resultados comprovaram a obten??o de nanocelulose a
partir do tecido de algod?o tingido com corante ?ndigo, tanto no processo via hidr?lise
?cida, como no de via enzim?tica. As imagens de microscopia indicaram nanocristais de
celulose com formato alongado (agulhas) a partir da hidr?lise ?cida. No caso da hidr?lise
enzim?tica, as imagens mostraram a presen?a de nanocelulose com formato esf?rico. A
hidr?lise ?cida realizada na condi??o de 65% a 45 C e tempo de 60 min resultou em nanocristais
com menor comprimento e di?metro, tanto para o tecido pr?-tratado como para o
sem pr?-tratamento. Com rela??o a hidr?lise enzim?tica, a realiza??o de pr?-tratamento
n?o alterou significativamente as caracter?sticas das estruturas micro e nanocristalina. O
tamanho m?dio das nanoceluloses obtidas foram na faixa de 80 a 230nm. Os resultados
do processo de hidr?lise enzim?tica indicam que as melhores convers?es de celulose em
glicose ocorreram utilizando o complexo enzim?tico produzido por Trichoderma reesei
ATCC 26921 com carga de enzima de 12 FPU e tempo de hidr?lise de 48h. Este trabalho
demonstrou que nanocristais de celulose podem ser obtidos a partir do tecido de algod?o
tingido com corante ?ndigo, sem a necessidade de pr?-tratamento para remo??o do corante, e as caracter?sticas dos nanomateriais obtidos dependem do processo de hidr?lise
utilizado. / Cellulose nanocrystals are nanomaterials derived from cellulose, which is a renewable and
abundant resource in nature. Due to combination of properties such as high mechanical
strength and modulus of elasticity, reactive surface and biodegradability, these materials
have received great attention for applications ranging from reinforcement in polymeric
materials, food packaging, to applications in the pharmaceutical area. The production of
nanometric cellulose from cotton fibers has been reported in several works published in
the literature. The objective of this research was to study the production of nanocellulose
from indigo-dyed cotton fibers from waste fabric, via acid and enzymatic hydrolysis
routes. Nanocellulose was obtained with and without pre-treatment for dye removal and
the effects of the pre-treatment on the characteristics of the nanocellulose were evaluated.
For the acid hydrolysis, two treatment conditions for the isolation of cellulose nanocrystals
were evaluated: sulfuric acid concentrations of 55% m / m at 60 C and 65% m/m
at 45 C, for 30 and 60 min. For the enzymatic hydrolysis, the influence of enzyme complex
type (Trichoderma reesei ATCC 26921 and Aspergillus fumigatus), time (0 to 48h)
and enzymatic load (7.5 and 12 FPU) were studied. The suspensions obtained after hydrolysis
were characterized by the techniques of zeta potential, atomic force microscopy,
transmission electron microscopy, infrared spectrophotometry, X-ray diffraction, thermogravimetric
analysis, total reducing sugars and high performance liquid chromatography.
The results demonstrated that nanocellulose was obtained from indigo dyed cotton fibers,
in both processing routes evaluated: via acid and enzymatic hydrolysis. Microscopy
images indicated needle shaped celulose from the acid hydrolysis. For the enzymatic hydrolysis,
the images showed the presence of nanocellulose with spherical shape. The acid
hydrolysis carried out at 65% at 45 C for 60 min resulted in nanocrystals of smaller length
and diameter, both for the pretreated fabric and the fabric without pretreatment. For the
enzymatic hydrolysis, the pretreatment did not affect significantly the characteristics of
the micro and nanocrystalline structures. The average size of the nanocellulose obtained
was in the range of 80 to 230 nm. The results of the enzymatic hydrolysis suggest that
the best cellulose to glucose conversions occurred using the enzymatic complex Trichoderma
reesei ATCC 26921 with enzymatic load of 12 FPU and hydrolysis time of 48h.
In summary, this study demonstrated that cellulose nanocrytals can be obtained from
indigo-dyed cotton fibers from waste fabric, without the need for pretreatment for dye
removal, and the characteristics of the nanomaterials obtained depend on the hydrolysis
process used.
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Modifica??o superficial do tecido 100% algod?o tratado com plasmaFreitas, Duciane Oliveira de 24 August 2009 (has links)
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Previous issue date: 2009-08-24 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The 100% cotton fabric (CO)* treated with plasma of methane CH4 has direct application in all areas that needs of aqueous solutions repellent material like coatings and uniforms applied biomedical, aeronautics, and automobile between
others. 100% cotton fabric (CO) samples were treated by plasma with two differents atmosphere: Methane gas (CH4), treatment time was varied in 10 in 10 min. until 60 min., and mixture methane/argon (CH4/Ar), it was varied the proportion 1:9, 2:8, 3:7, 4:6, 5:5, 6:4, 7:3, 8:2 e 9:1, with treatment time of 30 minutes. In both, the fluxe was 5 sccm (second cubic centimeter), pressure 6 mbar, voltage 490 V and current
0,15A. The objective of work was measure the superficial tension of 100% CO then it treated with plasma, using contact angle measures of water and glycerol with the
surface. The samples were tested after treatment, with 8 and 12 months to verify the superficial modification effects. It was verified an increase of hydrophobility with the Sessile drop values varied between 116,69? to 137,85? and it carried on after 12 months. The no treated samples shows contact angle equal 0?. OES analysis and Raman spectroscopy were accomplished. In the SEM analysis was verified oligomers. The plasma treatment is correct environmental, It turning greater than conventional treatments / O tecido 100% Algod?o (CO)* tratado com plasma de metano (CH4) tem aplica??o direta em todas as ?reas que necessitam de um material com maior repel?ncia a solu??es aquosas, como revestimentos e uniformes aplicados a ?rea biom?dica,
aeron?utica, automobil?stica, entre outras. Amostras de tecido 100% CO foram tratadas com plasma utilizando duas atmosferas diferentes: g?s CH4, com tempos que variaram de 10 em 10 min. at? 60 min., e uma mistura de metano/arg?nio
(CH4/Ar), em propor??es 1:9, 2:8, 3:7, 4:6, 5:5, 6:4, 7:3, 8:2 e 9:1, durante 30 min. O fluxo utilizado nos dois processos foi de 5 cm3/s (cent?metro c?bicos por segundo), a
uma press?o de 6 mbar , voltagem de 490 V e corrente de 0,15 A. O objetivo do trabalho foi medir a varia??o da tens?o superficial do tecido 100% CO ap?s tratado com plasma; Utilizando medidas de ?ngulo de contato da ?gua e do glicerol com a superf?cie. As amostras foram testadas imediatamente ap?s o tratamento, com 8 e 12 meses, a fim de verificar a dura??o do efeito desta modifica??o superficial. Verificou-se um aumento da hidrofobicidade atrav?s dos valores do teste da gota s?ssil que variaram entre 116,69? a 137,85? e se mantiveram ap?s 12 meses; As amostras n?o tratadas apresentam ?ngulo de contato igual a 0?. An?lises de
espectroscopia de emiss?o ?tica (EEO) e espectroscopia Raman (ER) foram realizadas, bem como, an?lise de microscopia eletr?nica de varredura (MEV) a qual confirmou presen?a de olig?meros. O processo a plasma ? ambientalmente correto e se torna superior em compara??o aos tratamentos convencionais
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