http://hdl.handle.net/2117/4020 2013-06-19T12:47:58Z http://hdl.handle.net/2117/19538 Title: Continuous reuse of water and electrolyte from decolorized reactive dyebaths Authors: López Grimau, Víctor; Gutiérrez Bouzán, María Carmen; Valldeperas Morell, José; Crespi Rosell, Martin Abstract: In this work, the feasibility of reusing water and salt from reactive dyebaths after electrochemical decolourization was evaluated. Dyeing series of ten reuses with three reactive dyes (Navy Blue Procion H-EXL, Crimson Procion H-EXL and Yellow Procion H-EXL) were carried out (individually and in a trichromie) and color differences and total organic carbon values were measured to study how the successive reuses affect the quality dyeing. The first reuse produced dyeings with low colour differences with respect to a standard dyeing. In the subsequent reuses, colour differences increased until they reached a constant value at the 4th or 5th reuse, following a similar behavior to the organic matter content. At this point, it is determined the percentage of dye increase that allows for continuous dyeing of acceptable quality for the textile industry. To obtain dyeings with acceptable color differences (DE ⁄ CMC (2:1) 6 1) independent of the number of consecutive reuses, a 30% increase in blue dyestuff and 10% for red dyestuff must be added, whereas in the case of yellow dyeing, it was not necessary to increase the dye amount after subsequent reuses. In each dyeing, this process allowed savings of 70% of water and an average of 60% for salt. 2013-06-12T07:24:13Z http://hdl.handle.net/2117/19355 Title: Washing wool with surfactants and a non-toxic solvent microemulsion: influence of water hardness Authors: Carrión Fité, Francisco Javier Abstract: In this work, detersive power (soil removal) was studied after washing a soiled wool fabric with addition of a non-toxic solvent microemulsion to conventional washing detergent formulations with the aim of improving the performance of the conventional washing. The non-toxic solvent used was dimethyl sulfoxide micro-dispersed with an amphoteric surfactant as emulsifier. The fabric was washed with biodegradable non-ionic surfactants such as an alcohol ethoxylate (AE) with 7 mE.O. and an alkyl polyglucoside with 1.4 glucoside groups (APG). The fabric used was EMPA 107 wool (soiled with standard impurities). The non-ionic surfactants were used separately and in mixture in varying proportions for the washes. Given the large amount of impurities in the wool fabric, sodium carbonate and sodium chloride were used to attain a suitable pH to avoid damaging the wool. The fabric was washed at low temperature with water of different hardness (20º hf, 30º hf and 40º hf). In addition, the sequestering agent DTPMP was used to obtain an improvement of detersive power at the hardness of 40º hf 2013-05-20T09:06:53Z http://hdl.handle.net/2117/18887 Title: Cyclodextrin functionalization of several cellulosic substrates for prolonged release of antibacterial agents Authors: Cusola Aumedes, Oriol; Tabary, Nicolas; Naceur Belgacem, Mohamed; Bras, Julien Abstract: Several cellulosic substrates have been surface-functionalized with cyclomaltoheptaose (b-cyclodextrin, b-CD) using citric acid as a crosslinker agent to obtain new surface-modified materials able to release antiseptic molecules over a prolonged period, in view of their use in medical domain. Three different commercial cellulosic substrates were used, namely: (i) an uncoated paper, (ii) a crepe paper, and (iii) a medical bandage. They were successfully grafted by a crosslinked polymer consisting on b-CD molecules as assessed by scanning electron microscopy and Fourier transform infrared spectroscopy analysis. Several time–temperature kinetic cycles were performed to reach the optimum curing parameters. The grafted and nongrafted samples were loaded with chlorhexidine digluconate (digCHX), a widely used antiseptic agent. The drug-delivery kinetics of the encapsulated digCHX was carried out by immersing the sample under investigation into an aqueous medium, and the quantity of the released digCHX was measured, as a function of time, by UV spectroscopy. The optimal grafting conditions were established on the basis of the highest weight gain. These samples did not give the best release performance. Nevertheless, several grafted substrates were able to uptake an appreciable amount of active molecules and release them over a prolonged time of about 20 days 2013-04-19T11:04:05Z http://hdl.handle.net/2117/18618 Title: The PVP/VI copolymer dye transfer inhibition agent during the washing of the polyester fabric Authors: Carrión Fité, Francisco Javier Abstract: The objective of this research was to study the effect of the copolymer polyvinylpyrrolidone/vinylimidazole (PVP/VI) for use as a dye transfer inhibitor (DTI) during the washing of dyed polyester fabric, depending on the detergent components. The DTI was used to find its efficiency during repeated washings of polyester fabric dyed with disperse dyes. At the same time, its efficiency was tested fer preventing dye migration to other fabrics, such as polyester, cellulose diacetate, acrylic, polyamide, cotton and wool. The influence of anionic (SDBS) and non-ionic (alkyl ethoxylates with 6 EO-groups) surfactants in different proportions and with zeolite as a builder and the aforementioned DTI was tested. Results of CIELAB colour differences were obtained for the dyed and undyed polyester fabrics after five washings 2013-04-04T13:50:03Z http://hdl.handle.net/2117/18297 Title: Application of surface enzyme treatments using laccase and a hydrophobic compound to paper-based media Authors: Cusola Aumedes, Oriol; Valls Vidal, Cristina; Vidal Lluciá, Teresa; Roncero Vivero, María Blanca Abstract: A new approach for the hydrophobization of finished cellulosic substrates based on a previously reported enzymatic technique is proposed. Commercial finished paper was hydrophobized by using laccase from Trametes villosa in combination with lauryl gallate (LG) as hydrophobic compound. The efficiency of the method was increased by the use of a lignosulfonate as a natural dispersant to improve the surface distribution of LG on the paper, raise its hydrophobicity and help preserve the enzyme activity. No similar threefold effect from a single compound for the improvement of enzymatic treatments was previously reported. The influence of processing conditions including the LG dose, treatment time and temperature was also examined, resulting in further increased hydrophobicity. Efficient fiber bonding and chemical functionalization were confirmed by thorough washing and Soxhlet extraction of the paper. As shown here for the first time, enzyme treatments have the potential to improve the surface hydrophobicity of paper-based media 2013-03-14T11:44:20Z http://hdl.handle.net/2117/18230 Title: Laccase from Pycnoporus cinnabarinus and phenolic compounds: can the efficiency of an enzyme mediator for delignifying kenaf pulp be predicted? Authors: Andreu Terrén, Glòria; Vidal Lluciá, Teresa Abstract: In this work, kenaf pulp was delignified by using laccase in combination with various redox mediators and the efficiency of the different laccase–mediator systems assessed in terms of the changes in pulp properties after bleaching. The oxidative ability of the individual mediators used (acetosyringone, syringaldehyde, p-coumaric acid, vanillin and actovanillone) and the laccase–mediator systems was determined by monitoring the oxidation–reduction potential (ORP) during process. The results confirmed the production of phenoxy radicals of variable reactivity and stressed the significant role of lignin structure in the enzymatic process. Although changes in ORP were correlated with the oxidative ability of the mediators, pulp properties as determined after the bleaching stage were also influenced by condensation and grafting reactions. As shown here, ORP measurements provide a first estimation of the delignification efficiency of a laccase–mediator system. 2013-03-12T16:04:36Z http://hdl.handle.net/2117/18145 Title: Enzymatic grafting of natural phenols to flax fibres: development of antimicrobial properties Authors: Fillat Latorre, Amanda; Gallardo Román, Óscar; Vidal Lluciá, Teresa; Pastor Blasco, Francisco I. Javier; Díaz Lucea, Pilar; Roncero Vivero, María Blanca Abstract: Unbleached flax fibres for paper production were treated with laccase from Pycnoporus cinnabarinus and low molecular weight phenols (syringaldehyde – SA, acetosyringone – AS and p-coumaric acid – PCA) to evaluate the potential of this treatment to biomodify high cellulose content fibres. After the enzymatic treatment with the phenols, an increase in kappa number was found, probably due to a covalent binding of the phenoxy radicals on fibres. Grafting was more evident in pulps treated with PCA (an increase of 4 kappa number points with respect to the laccase control was achieved). Paper handsheets from treated pulps showed antimicrobial activity against the bacteria tested: Staphylococcus aureus, Pseudomonas aeruginosa and Klebsiella pneumoniae. An important reduction on microbial count was obtained after incubation of liquid cultures of the bacteria with grafted handsheets. AS and PCA grafted fibres showed a high antibacterial activity on K. pneumoniae, getting a nearly total growth inhibition. AS fibres also caused a high reduction in bacterial population of P. aeruginosa (97% reduction). Optical properties of handsheets from treated pulps were also determined, showing a brightness decrease and increase in coloration, evaluated by CIE L*a*b* system, caused by the laccase induced grafting of the phenols. The results suggest that these low molecular weight phenols, covalently bound to the flax fibres by the laccase treatment, can act as antimicrobial agents and produce handsheets with antimicrobial activity 2013-03-08T11:09:37Z http://hdl.handle.net/2117/17932 Title: Use of cyclic voltammetry as an effective tool for selecting effcient enhancers for oxidative bioprocesses: importance of pH Authors: Aracri, Elisabetta; Tzanov, Tzanko; Vidal Lluciá, Teresa Abstract: Seven natural phenols and two synthetic compounds were evaluated by means of cyclic voltammetry as enhancers for the oxidation of the lignin model compound veratryl alcohol (VAl) and a sulfonated lignin (SL). Their electrochemical behaviors and catalytic efficiencies (CEs) against both substrates were assessed as a function of pH. A general increase in CE of the phenols was for the first time observed in the oxidation of VAl at pH 7 and 8. Methyl syringate (MS), syringic acid (SRC), and syringaldehyde (SRD) exhibited the highest CEs against VAl among the studied phenolic compounds despite the reduced stabilities of their phenoxy radicals. This was a result of favorable stability−reactivity balances, which were apparently influenced by both the chemical structures of the enhancers and the experimental conditions. Violuric acid (VAc) proved the most efficient compound in oxidizing lignin, followed by SRD and MS, which showed regeneration in the interval of pHs studied 2013-02-22T11:50:22Z http://hdl.handle.net/2117/17435 Title: Performance of new and commercial xylanases for ECF and TCF bleaching of eucalyptus kraft pulp Authors: Valls Vidal, Cristina; Gallardo Román, Óscar; Vidal Lluciá, Teresa; Pastor Blasco, Francisco I. Javier; Díaz Lucea, Pilar; Roncero Vivero, María Blanca Abstract: Since xylanases can differ widely in their bleaching efficiency, the performance of one new and two commercial xylanases was evaluated in an eucalyptus kraft pulp following XD (X: xylanase; D: chlorine dioxide) and XP (P: hydrogen peroxide) sequences. The new xylanase did not show a significant bleach boosting effect but increased the hexenuronic acid (HexA) removal by 10% after the D stage. The two commercial xylanases behaved in a different way, being one of them (XC) the most effective in increasing delignification (9%) and brightness (3%ISO). Its effectiveness was related to its greater action on releasing the xylan polymer, thus producing also a strong decrease in the HexA contents during the enzymatic stage (15%). All xylanases produced morphological changes in the fibre surfaces, but only with XC cracks and holes that improved the diffusion of reactives were observed. Finally, the best bleaching results were obtained with the XD sequence and therefore, a complete bleaching sequence XDEopD1 (Eop: alkaline extraction with oxygen and peroxide) was carried out with the best enzyme 2013-01-21T12:01:00Z http://hdl.handle.net/2117/17415 Title: Controle da ensimagem na fiaçao Authors: Marsal Amenós, Félix Abstract: O autor mostra, por meio de experimentos, novo método para avaliar a eficácia dos produtos no pré-tratamento dos fios 2013-01-18T08:46:15Z http://hdl.handle.net/2117/17414 Title: Las tendencias de la industria de hilados Authors: Marsal Amenós, Félix 2013-01-18T08:29:57Z http://hdl.handle.net/2117/17398 Title: Nuevo método para la aplicación de las microcápsulas en hilatura Authors: Marsal Amenós, Félix; Palet Alsina, Daniel Abstract: Se ha puesto a punto un nuevo método que permite aplicar todo tipo de microcápsulas en el proceso de hilatura, tanto de las fibras cortas como de las fibras largas, para todos aquellos hilos fabricados en continuas de hilar de anillos. La colocación de las microcápsulas en los intersticios del hilo, antes de impartirse la torsión, permite resolver el problema de la permanencia del efecto aportado por los principios activos contenidos en la microcápsula, para la funcionalidad y uso de las prendas textiles, frente a los lavados repetidos 2013-01-17T13:15:26Z http://hdl.handle.net/2117/17397 Title: Control de los ensimajes en hilatura Authors: Marsal Amenós, Félix Abstract: Se propone un método para valorar la eficacia de un ensimaje, aplicado en el proceso de hilatura, de fácil aplicación industrial y bien correlacionado con la calidad del hilo y de los tejidos obtenidos. Método válido para los procesos de hilatura de fibra cortada, independientemente de su longitud de corte y de finura de las fibras 2013-01-17T13:04:42Z http://hdl.handle.net/2117/17396 Title: Determinación de Trash y Neps: ventajas tecnológicas para la hilatura Authors: Marsal Amenós, Félix Abstract: En este trabajo se aplica el medidor NATI (Neps And Trash Indicator) en la determinación del contenido de neps y de trash en las cintas y mechas de algodón. Este nuevo equipo es también aplicable a otras fibras, distintas del algodón, ya sean naturales, sintéticas o mezclas de fibras entre sí, que contengan neps y trash y a su vez puede utilizarse para otras formas de presentación de la materia textil, como son las flocas. Se han determinado las condiciones óptimas de trabajo del instrumento y el poder de eliminación de neps y trash en diferentes cardas, comparando los valores de la floca de entrada a la carda y los neps en el hilo, determinados en el regularímetro de masa. Los resultados obtenidos constatan una buena correlación entre los neps detectados en la cinta de carda y los neps indicados en el regularímetro, cuando se analiza el hilo que se entrega al tejedor 2013-01-17T12:58:00Z http://hdl.handle.net/2117/17384 Title: Simulation of bleaching of soda pulp from Hesperaloe funifera by polynomial and neural fuzzy models Authors: Rosal, Antonio; Valls Vidal, Cristina; Roncero Vivero, María Blanca; Rodríguez Pascual, Alejandro Abstract: Influence of variables [soda, (0.5 to 3.0%), hydrogen peroxide (1.0 to 10.0%) and time (1 to 5 h)] in the bleaching of soda pulp of Hesperaloe funifera, on the properties of bleached pulps, was studied. Polynomial and neural fuzzy models had reproduced the results of Kappa number, brightness and viscosity of the pulps with errors less than 10 and 15%, respectively. By simulating the bleaching process of pulp H. funifera, with the polynomial and neural fuzzy models, the optimal values of operating variables can be found, so that the properties of bleached pulps differ little from their best values and instead will save chemical reagents, energy and plant size, operating with lower values of operating variables. Thus, by application of polynomial models, it was found that operating with a soda concentration of 0.5%, a hydrogen peroxide concentration of 5.5% and for a processing time of 3 h, it was possible to get a pulp with a brightness of 65.9% and a viscosity of 587 ml/g. 2013-01-16T10:48:32Z