Departament d'Enginyeria Tèxtil i Paperera
http://hdl.handle.net/2117/4019
2024-03-28T09:32:56ZCellulose oxidation by Laccase-TEMPO treatments
http://hdl.handle.net/2117/100104
Cellulose oxidation by Laccase-TEMPO treatments
Quintana, Elisabet; Roncero Vivero, María Blanca; Vidal Lluciá, Teresa; Valls Vidal, Cristina
In this work, laccase-TEMPO (Lac-T) treatments were applied to bleached commercial dissolving pulp in order to introduce carbonyl and carboxyl groups, which were found to improve dry and wet strength-related properties. Also the solubility behavior towards xanthate reactions was assessed. The effect of a refining step (R) before the oxidative treatment, the absence or presence of oxygen pressure, TEMPO dose (2 or 8% oven dried pulp) and reaction time (8 or 20 h) were thoroughly examined. Treatments conducted in the presence of oxygen pressure exhibited greater amount of functional groups. Introducing a pre-refining treatment resulted in similar functional groups but higher wet strength was achieved. Specifically, a high W/D strength ratio was observed, indicating that wet strength-related property was satisfactorily developed. Besides the fact that all Lac-T treatments caused severe cellulose degradation, no fiber strength loss was detected. In fact, all oxidized samples presented higher Wet Zero-Span Tensile Strength, mainly in R+ Lac-T (O2) sample, which suggested the formation of hemiacetal linkages between the new introduced aldehyde groups and available free hydroxyl groups resulting from fibrillation
2017-01-26T11:55:12ZQuintana, ElisabetRoncero Vivero, María BlancaVidal Lluciá, TeresaValls Vidal, CristinaIn this work, laccase-TEMPO (Lac-T) treatments were applied to bleached commercial dissolving pulp in order to introduce carbonyl and carboxyl groups, which were found to improve dry and wet strength-related properties. Also the solubility behavior towards xanthate reactions was assessed. The effect of a refining step (R) before the oxidative treatment, the absence or presence of oxygen pressure, TEMPO dose (2 or 8% oven dried pulp) and reaction time (8 or 20 h) were thoroughly examined. Treatments conducted in the presence of oxygen pressure exhibited greater amount of functional groups. Introducing a pre-refining treatment resulted in similar functional groups but higher wet strength was achieved. Specifically, a high W/D strength ratio was observed, indicating that wet strength-related property was satisfactorily developed. Besides the fact that all Lac-T treatments caused severe cellulose degradation, no fiber strength loss was detected. In fact, all oxidized samples presented higher Wet Zero-Span Tensile Strength, mainly in R+ Lac-T (O2) sample, which suggested the formation of hemiacetal linkages between the new introduced aldehyde groups and available free hydroxyl groups resulting from fibrillationEvaluating drape shape in woven fabrics
http://hdl.handle.net/2117/99840
Evaluating drape shape in woven fabrics
Carrera Gallissà, Enric; Capdevila Juan, Francisco Javier; Valldeperas Morell, Josep
A search of the scientific literature for the period 1950–2013 retrieved 36 different drape indicators. Despite the large number of indicators currently available, the drape ratio (%DR) continues to be the most widely used, even though it has proved inadequate to explain drape shape. In order to assess their actual performance, the 36 currently existing drape indicators were determined in a total of 37 commercial drapery, woolmaking, shirtmaking and lining woven fabrics spanning a wide range of composition, aerial weight and weave type by using a digital Cusick drape meter. A correlation analysis between indicators, and subsequent suppression of duplicity and collinearity, revealed that seven were mutually correlated. A principal component analysis of the results revealed an underlying structure consisting of three common factors which allowed the indicators to be classified into three different groups according to drape intensity (a), severity (b), and shape symmetry and variability (c). Cluster analysis was additionally used to examine the results in graphical form and exposed three clusters coinciding with the three factors of the underlying structure. A criterion for distinguishing fabrics with an identical drape ratio in terms of drape shape based on sequential application of four of the seven initially selected indicators was developed and experimentally validated
2017-01-23T11:08:28ZCarrera Gallissà, EnricCapdevila Juan, Francisco JavierValldeperas Morell, JosepA search of the scientific literature for the period 1950–2013 retrieved 36 different drape indicators. Despite the large number of indicators currently available, the drape ratio (%DR) continues to be the most widely used, even though it has proved inadequate to explain drape shape. In order to assess their actual performance, the 36 currently existing drape indicators were determined in a total of 37 commercial drapery, woolmaking, shirtmaking and lining woven fabrics spanning a wide range of composition, aerial weight and weave type by using a digital Cusick drape meter. A correlation analysis between indicators, and subsequent suppression of duplicity and collinearity, revealed that seven were mutually correlated. A principal component analysis of the results revealed an underlying structure consisting of three common factors which allowed the indicators to be classified into three different groups according to drape intensity (a), severity (b), and shape symmetry and variability (c). Cluster analysis was additionally used to examine the results in graphical form and exposed three clusters coinciding with the three factors of the underlying structure. A criterion for distinguishing fabrics with an identical drape ratio in terms of drape shape based on sequential application of four of the seven initially selected indicators was developed and experimentally validatedLow-temperature plasma treatments in the design of polypropylene surgical meshes for hernia repair
http://hdl.handle.net/2117/97117
Low-temperature plasma treatments in the design of polypropylene surgical meshes for hernia repair
Labay, Cédric Pierre; Canal Barnils, Cristina; Navarro Sentanyes, Antonio; Canal Arias, José María
One of the new trends in textile biomaterials research is to deliver active compounds locally in the surgical site from the medical device. One way to manage post-operatory infections associated with mesh implants in abdominal hernia repair surgery can be the loading of antibiotics to the surgical textile meshes. In a novel approach to design an advanced drug-delivery systems based on surgical meshes, low-temperature plasma processes have been used to tailor the surface properties of polypropylene meshes to obtain high loading of ampicillin, maintaining the biological adhesion and the antibacterial activity of the current surgical meshes [1].
Plasma treatment of polymer fibers has been commonly employed to tailor surface adhesion and wetting properties by changing the surface chemical composition [2-3]. Appropriate selection of the plasma source enables the introduction of diverse functional groups on the target surface to improve wettability, biocompatibility or to allow subsequent covalent immobilization or physical adsorption of various molecules such as dyestuffs, pharmaceutical or cosmetic active principles [4-5]. Plasma can also be used for the deposition of polymer thin coatings by the so-called plasma polymerization process [6]. By modifying the process parameters of the plasma and the precursor molecule, different kinds of biocompatible coatings can be produced, from cell-adhesive to antifouling coatings.
In this work, low-temperature plasma processes have been used to tailor the surface properties of polypropylene meshes, in a novel approach, to obtain high loadings of ampicillin, maintaining the biological adhesion and the antibacterial activity of the current surgical meshes [1].
As a first-step in the design of the antibiotic-loaded surgical mesh, plasma functionalization of the polymer surface with polar oxygen groups was used to modify the polypropylene fiber surface at a nanometric level. Surface wettability was improved and the availability of chemical bonds (C-O, C=O) increased. This was employed for the subsequent attachment of ampicillin allowing increasing its loading as function of the plasma treatment time. The chemical and morphological changes produced on the surface of polypropylene fibers lead to a 3-fold improvement of the ampicillin loading in the meshes after only 3.5 s of plasma treatment.
However, this plasma treatment and the subsequent loading of the ampicillin in the polypropylene fibers were related with lower fibroblast adhesion, altered morphology and enhanced chemotaxis. Thus, plasma polymerization was used as dry method to create a thin coating of polyethylene glycol with the aim of keeping the high antibiotic loadings obtained with plasma functionalization and to maintain essentially unchanged fibroblast properties such as chemotaxis or adhesion with respect to untreated meshes, fulfilling the requirement of biocompatible device for the finished antibiotic-loaded mesh.
Beyond the added value brought by the loading of an antibiotic to the mesh for its release directly to the surgical site, the use of plasma processes in the design of biomaterials brings an original approach to control simultaneously physic-chemical properties and regarding the treatment of the mesh without the use of any other chemicals for the binding of the active principle with the fiber.
2016-11-23T12:35:38ZLabay, Cédric PierreCanal Barnils, CristinaNavarro Sentanyes, AntonioCanal Arias, José MaríaOne of the new trends in textile biomaterials research is to deliver active compounds locally in the surgical site from the medical device. One way to manage post-operatory infections associated with mesh implants in abdominal hernia repair surgery can be the loading of antibiotics to the surgical textile meshes. In a novel approach to design an advanced drug-delivery systems based on surgical meshes, low-temperature plasma processes have been used to tailor the surface properties of polypropylene meshes to obtain high loading of ampicillin, maintaining the biological adhesion and the antibacterial activity of the current surgical meshes [1].
Plasma treatment of polymer fibers has been commonly employed to tailor surface adhesion and wetting properties by changing the surface chemical composition [2-3]. Appropriate selection of the plasma source enables the introduction of diverse functional groups on the target surface to improve wettability, biocompatibility or to allow subsequent covalent immobilization or physical adsorption of various molecules such as dyestuffs, pharmaceutical or cosmetic active principles [4-5]. Plasma can also be used for the deposition of polymer thin coatings by the so-called plasma polymerization process [6]. By modifying the process parameters of the plasma and the precursor molecule, different kinds of biocompatible coatings can be produced, from cell-adhesive to antifouling coatings.
In this work, low-temperature plasma processes have been used to tailor the surface properties of polypropylene meshes, in a novel approach, to obtain high loadings of ampicillin, maintaining the biological adhesion and the antibacterial activity of the current surgical meshes [1].
As a first-step in the design of the antibiotic-loaded surgical mesh, plasma functionalization of the polymer surface with polar oxygen groups was used to modify the polypropylene fiber surface at a nanometric level. Surface wettability was improved and the availability of chemical bonds (C-O, C=O) increased. This was employed for the subsequent attachment of ampicillin allowing increasing its loading as function of the plasma treatment time. The chemical and morphological changes produced on the surface of polypropylene fibers lead to a 3-fold improvement of the ampicillin loading in the meshes after only 3.5 s of plasma treatment.
However, this plasma treatment and the subsequent loading of the ampicillin in the polypropylene fibers were related with lower fibroblast adhesion, altered morphology and enhanced chemotaxis. Thus, plasma polymerization was used as dry method to create a thin coating of polyethylene glycol with the aim of keeping the high antibiotic loadings obtained with plasma functionalization and to maintain essentially unchanged fibroblast properties such as chemotaxis or adhesion with respect to untreated meshes, fulfilling the requirement of biocompatible device for the finished antibiotic-loaded mesh.
Beyond the added value brought by the loading of an antibiotic to the mesh for its release directly to the surgical site, the use of plasma processes in the design of biomaterials brings an original approach to control simultaneously physic-chemical properties and regarding the treatment of the mesh without the use of any other chemicals for the binding of the active principle with the fiber.Surface treatment of denim fabric for selective fading
http://hdl.handle.net/2117/96613
Surface treatment of denim fabric for selective fading
Carrión Fité, Francisco Javier
A growing customer demand currently exists for denim apparel with a used, worn, faded appearance or even holes in the fabric. In this work, we examined the effect of treating denim with an aqueous solution of an oxidant prior to UV-C irradiation for localized fading of the fabric in order to obtain the faded, worn apperance sought by some jeans users. We propose a new technology using ultraviolet light in combination with an oxidant to modulate the degree of fading of denim fabric
2016-11-14T12:44:11ZCarrión Fité, Francisco JavierA growing customer demand currently exists for denim apparel with a used, worn, faded appearance or even holes in the fabric. In this work, we examined the effect of treating denim with an aqueous solution of an oxidant prior to UV-C irradiation for localized fading of the fabric in order to obtain the faded, worn apperance sought by some jeans users. We propose a new technology using ultraviolet light in combination with an oxidant to modulate the degree of fading of denim fabricPrevent redeposition of solid impurities during washing synthetic fabrics
http://hdl.handle.net/2117/96597
Prevent redeposition of solid impurities during washing synthetic fabrics
Carrión Fité, Francisco Javier
The textile washing process involves basically three stages: (1) removing the soiling from the substrate, (2) suspending the soling removed in the washing bath and (3) preventing redeposition of the soiling onto the substrate from which it has just been removed. In fact, soiling removed from the substrate may have deposited on it to a greater or lesser extent during the detergent process, as unwanted phenomenon that can be avoided using appropriate polymers. Preventing the redeposition of impurities is especially important during the washing of synthetic fibres with a compact crystal structure such as polyester or acrylics. The primary purpose of this work was to assess the performance of a polyethylene glycol polyester copolymer used as a detergent additive to prevent redeposition of solid impurities during the washing of standard polyester and acrylic fabrics in terms of the zeta potential of the fabrics. The copolymer was used in combination with the anionic surfactant, sodium dodecylbenzenesulfonate, the non-ionic surfactant fatty alcohol ethoxylate with 7 mol E.O. or both in variable proportions. The soiling used as a solid impurity in the washing process was carbon black. The observed behaviour is explained in terms of the electrical double layer of the fabrics, which was characterised separately with each surfactant and their mixture
2016-11-14T11:07:12ZCarrión Fité, Francisco JavierThe textile washing process involves basically three stages: (1) removing the soiling from the substrate, (2) suspending the soling removed in the washing bath and (3) preventing redeposition of the soiling onto the substrate from which it has just been removed. In fact, soiling removed from the substrate may have deposited on it to a greater or lesser extent during the detergent process, as unwanted phenomenon that can be avoided using appropriate polymers. Preventing the redeposition of impurities is especially important during the washing of synthetic fibres with a compact crystal structure such as polyester or acrylics. The primary purpose of this work was to assess the performance of a polyethylene glycol polyester copolymer used as a detergent additive to prevent redeposition of solid impurities during the washing of standard polyester and acrylic fabrics in terms of the zeta potential of the fabrics. The copolymer was used in combination with the anionic surfactant, sodium dodecylbenzenesulfonate, the non-ionic surfactant fatty alcohol ethoxylate with 7 mol E.O. or both in variable proportions. The soiling used as a solid impurity in the washing process was carbon black. The observed behaviour is explained in terms of the electrical double layer of the fabrics, which was characterised separately with each surfactant and their mixtureCrosstalk characterization of fabrics elaborated with conductive yarns
http://hdl.handle.net/2117/91038
Crosstalk characterization of fabrics elaborated with conductive yarns
Fernández García, Raúl; Gil Galí, Ignacio; Cano Casas, Francesc; Parés Sabatés, Ferran
The electrical characterization of crosstalk of fabrics elaborated with conductive yarns is investigated. The impact of the source, victim and ground traces location is reported. The experimental results show that the crosstalk in fabrics is higher in comparison with other conductive media. Nevertheless, the results show that the standard strategies to reduce the coupling between lines can be used on fabrics. Doing this, fabrics elaborated with conductive yarns can be used as a conductive media for digital buses, which can help to improve the integration of electronic devices in textile.
2016-10-25T07:26:34ZFernández García, RaúlGil Galí, IgnacioCano Casas, FrancescParés Sabatés, FerranThe electrical characterization of crosstalk of fabrics elaborated with conductive yarns is investigated. The impact of the source, victim and ground traces location is reported. The experimental results show that the crosstalk in fabrics is higher in comparison with other conductive media. Nevertheless, the results show that the standard strategies to reduce the coupling between lines can be used on fabrics. Doing this, fabrics elaborated with conductive yarns can be used as a conductive media for digital buses, which can help to improve the integration of electronic devices in textile.Correlation analysis between the Kawabata System (KES-F) and the UPC ring methods of fabric analysis
http://hdl.handle.net/2117/90964
Correlation analysis between the Kawabata System (KES-F) and the UPC ring methods of fabric analysis
Carrera Gallissà, Enric; Capdevila Juan, Francisco Javier; Valldeperas Morell, José
A total of 37 commercial woven fabrics of variable composition, weave type and aerial weight were studied by using the Kawabata Evaluation System for Fabrics (KES-F) and a modified version of the ring method called the “UPC ring method” that was developed by the authors in previous work. The parameters of the KES-F system were correlated with those of the UPC ring method via canonical correlation analysis
2016-10-24T08:56:10ZCarrera Gallissà, EnricCapdevila Juan, Francisco JavierValldeperas Morell, JoséA total of 37 commercial woven fabrics of variable composition, weave type and aerial weight were studied by using the Kawabata Evaluation System for Fabrics (KES-F) and a modified version of the ring method called the “UPC ring method” that was developed by the authors in previous work. The parameters of the KES-F system were correlated with those of the UPC ring method via canonical correlation analysisEffect of chain extender and water-quenching on the properties of poly(3-hydroxybutyrate-co-4-hydroxybutyrate) foams for its production by extrusion foaming
http://hdl.handle.net/2117/90797
Effect of chain extender and water-quenching on the properties of poly(3-hydroxybutyrate-co-4-hydroxybutyrate) foams for its production by extrusion foaming
Ventura Casellas, Heura; Laguna-Gutiérrez, Ester; Rodríguez Pérez, Miguel Ángel; Ardanuy Raso, Mònica
Bacterial polyesters such as polyhydroxyalkanoates (PHAs) are of great interest for a large number of applications both because of their properties and because they come from renewable resources, despite having a higher cost than commodity polymers. Their foaming—although it presents some difficulties—could be an option to increase their competitiveness. In this work, two strategies have been studied to enhance the poly(3-hydoxybutyrate-co-4-hydroxybutyrate) (P3HB4HB) foamability by extrusion foaming. The effect of the cooling system (water-quenching or air-cooling), chain extender (CE) addition and chemical blowing agent (CBA) amount were evaluated. Density, cellular morphology, mechanical and thermal properties were studied. Optimal density reduction was achieved with use of CE and 3–4 wt.% of CBA masterbatch. The most effective strategy on density reduction was the addition of CE, while the water quenching had only a slight influence on the samples in which CE was not present. CE addition decreased the viscosity and the degradation rate of the polymer, thus leading to lighter foams with larger cells but with equal or even slightly better resistance to compressive and tensile stress, in general terms
2016-10-17T11:43:48ZVentura Casellas, HeuraLaguna-Gutiérrez, EsterRodríguez Pérez, Miguel ÁngelArdanuy Raso, MònicaBacterial polyesters such as polyhydroxyalkanoates (PHAs) are of great interest for a large number of applications both because of their properties and because they come from renewable resources, despite having a higher cost than commodity polymers. Their foaming—although it presents some difficulties—could be an option to increase their competitiveness. In this work, two strategies have been studied to enhance the poly(3-hydoxybutyrate-co-4-hydroxybutyrate) (P3HB4HB) foamability by extrusion foaming. The effect of the cooling system (water-quenching or air-cooling), chain extender (CE) addition and chemical blowing agent (CBA) amount were evaluated. Density, cellular morphology, mechanical and thermal properties were studied. Optimal density reduction was achieved with use of CE and 3–4 wt.% of CBA masterbatch. The most effective strategy on density reduction was the addition of CE, while the water quenching had only a slight influence on the samples in which CE was not present. CE addition decreased the viscosity and the degradation rate of the polymer, thus leading to lighter foams with larger cells but with equal or even slightly better resistance to compressive and tensile stress, in general termsEffect of different dispersing agents in the non-isothermal kinetics and thermomechanical behavior of PET/TiO2 composites
http://hdl.handle.net/2117/90738
Effect of different dispersing agents in the non-isothermal kinetics and thermomechanical behavior of PET/TiO2 composites
Cayuela Marín, Diana; Cot Valle, María Ana; Algaba Joaquín, Inés María; Manich Bou, Albert M.
This work is based on the analysis of the influence of dispersing agents on the non-isothermal kinetics, thermomechanical behavior and dispersing action of PET/TiO2 nanocomposites. The influence of two montanic waxes and an amide wax used as dispersing agents in the nucleating effect of the nanoparticles is studied. The dispersing agents are the following: a) a partly saponified ester of montanic acids (PSEMA), b) an ester of montanic acids with multifunctional alcohols (MAWMA) and c) an amide wax based on N,N '-Bisstearoyl ethylenediamine (AW). The non-isothermal kinetics based on the Avrami method revealed that MAWMA and PSEMA favors the nucleating effect of the nanoparticles when are included in PET. Birefringence microscopy points out the good dispersing capacity of MAWMA and AW and the termomechanical analysis confirmed that the ester of montanic acids with multifunctional alcohols MAWMA shows the best dispersing properties and best promotes the nucleating effect of the TiO2 nanoparticles when used for PET/TiO2 nanocomposites production
2016-10-13T12:07:45ZCayuela Marín, DianaCot Valle, María AnaAlgaba Joaquín, Inés MaríaManich Bou, Albert M.This work is based on the analysis of the influence of dispersing agents on the non-isothermal kinetics, thermomechanical behavior and dispersing action of PET/TiO2 nanocomposites. The influence of two montanic waxes and an amide wax used as dispersing agents in the nucleating effect of the nanoparticles is studied. The dispersing agents are the following: a) a partly saponified ester of montanic acids (PSEMA), b) an ester of montanic acids with multifunctional alcohols (MAWMA) and c) an amide wax based on N,N '-Bisstearoyl ethylenediamine (AW). The non-isothermal kinetics based on the Avrami method revealed that MAWMA and PSEMA favors the nucleating effect of the nanoparticles when are included in PET. Birefringence microscopy points out the good dispersing capacity of MAWMA and AW and the termomechanical analysis confirmed that the ester of montanic acids with multifunctional alcohols MAWMA shows the best dispersing properties and best promotes the nucleating effect of the TiO2 nanoparticles when used for PET/TiO2 nanocomposites productionReuse of textile dyeing effluents treated with coupled nanofiltration and electrochemical processes
http://hdl.handle.net/2117/90621
Reuse of textile dyeing effluents treated with coupled nanofiltration and electrochemical processes
Buscio Olivera, Valentina; García Jiménez, María; Vilaseca Vallvé, M. Mercedes; López Grimau, Víctor; Crespi Rosell, Martin; Gutiérrez Bouzán, María Carmen
The reactive dye Cibacron Yellow S-3R was selected to evaluate the feasibility of combining nanofiltration membranes with electrochemical processes to treat textile wastewater. Synthetic dyeing effluents were treated by means of two nanofiltration membranes, Hydracore10 and Hydracore50. Up to 98% of dye removal was achieved. The influence of salt concentration and pH on membrane treatment was studied. The best dye removal yield was achieved at pH 3 in the presence of 60 g/L of NaCl. After the membrane filtration, the concentrate containing high dye concentration was treated by means of an electrochemical process at three different current densities: 33, 83, and 166 mA/cm2. Results showed a lineal relationship between treatment time and applied current density. Both permeates and electrochemically-decoloured effluents were reused in new dyeing processes (100% of permeate and 70% of decoloured concentrates). Dyed fabrics were evaluated with respect to original dyeing. Colour differences were found to be into the acceptance range
2016-10-10T10:04:47ZBuscio Olivera, ValentinaGarcía Jiménez, MaríaVilaseca Vallvé, M. MercedesLópez Grimau, VíctorCrespi Rosell, MartinGutiérrez Bouzán, María CarmenThe reactive dye Cibacron Yellow S-3R was selected to evaluate the feasibility of combining nanofiltration membranes with electrochemical processes to treat textile wastewater. Synthetic dyeing effluents were treated by means of two nanofiltration membranes, Hydracore10 and Hydracore50. Up to 98% of dye removal was achieved. The influence of salt concentration and pH on membrane treatment was studied. The best dye removal yield was achieved at pH 3 in the presence of 60 g/L of NaCl. After the membrane filtration, the concentrate containing high dye concentration was treated by means of an electrochemical process at three different current densities: 33, 83, and 166 mA/cm2. Results showed a lineal relationship between treatment time and applied current density. Both permeates and electrochemically-decoloured effluents were reused in new dyeing processes (100% of permeate and 70% of decoloured concentrates). Dyed fabrics were evaluated with respect to original dyeing. Colour differences were found to be into the acceptance range