164 research outputs found
Reduction of the formaldehyde content in leathers treated with formaldehyde resins by means of plant polyphenols
Formaldehyde has applications in many industrial processes, including synthesis of resins and syntans to be used in the retanning process of leather. When resins are employed, they can hydrolyse, releasing formaldehyde. Due to the carcinogenicity of formaldehyde, its presence in leather should be avoided or kept below allowable limits.
The aim of this study is to determine the effect of polyphenols contained in vegetable compounds (mimosa, quebracho and tara) in the reduction of the formaldehyde content in leathers treated with resins synthesized with formaldehyde (melamine-formaldehyde and dicyandiamide-formaldehyde). The formaldehyde content in leathers treated only with resin increases with time while the formaldehyde content in leathers treated additionally with vegetable compounds is reduced. The lower the formaldehyde content in the leather, the higher the ability of vegetable compounds to reduce such content. Mimosa shows the strongest ability to reduce the formaldehyde content, and this capacity increases with ageing. The addition of 4% (on shaved wet-blue weight) of mimosa gives rise to an 85% reduction in the formaldehyde content 140 days after leather processing of split hides treated with a formaldehyde resin of low formaldehyde content. However, this reduction is 68% in splits hides treated with a resin of high formaldehyde content. This is of great importance in baby’s leather articles, in which the formaldehyde content is low; therefore, the addition of a small amount (3%) of vegetable compounds (especially mimosa) guarantees that the formaldehyde content is below the allowed limits (16 mg/kg in the most restrictive regulation). Reducing the formaldehyde content using the polyphenols contained in vegetable compounds constitutes a good alternative not only in the leather sector but also in other industrial sectors (wood, textile, etc.) that use formaldehyde resins.Peer ReviewedPostprint (published version
Tinta curable y sus aplicaciones, en procedimientos de estampación
Tinta curable y sus aplicaciones, en procedimientos de
estampación.
La presente invención se refiere a una tinta curable útil para
inyección de chorro de tinta o para serigrafía, que tiene
una tensión superficial comprendida entre 30 y 55 mN/m
y una viscosidad comprendida entre 10 cps y 35 cps y
porque comprende los siguientes elementos: agua sin o
con un disolvente orgánico como vehículo, un colorante
y/o pigmento disueltos en agua, una resina fotocurable
por UV formadora de la película, entre 20-50% del peso
de la tinta, uno o más monómero como flexibilizante de la
película y diluyente, un fotoiniciador y un dispersante y/o
tensioactivo, opcionalmente para el caso de una tinta de
serigrafía, un espesante.Consejo Superior de Investigaciones Científicas (CEspaña), Consorci Escola Industrial de BarcelonaB1 Patente con informe sobre el estado de la ténic
Seam slippage and seam strength behavior of elastic woven fabrics under static loading
Effects of fabric extensibility and stitch density on seam slippage and strength behavior of elastic woven fabrics have been studied. Six fabric samples with different values of elasticity have been woven by changing the number of elastic core-spun cotton yarns and normal ring cotton yarns in the weft direction and then finished for sewing process. The samples are sewn with three stitch density levels (4, 5 and 6 stitches/cm) in warp direction and one stitch density level (5 stitches/cm) in weft direction. Fabric tensile properties, seam slippage load and seam strength have been measured and analyzed both in warp and weft directions. The results show that seam slippage and strength properties can be well explained in terms of fabric tensile properties. In general, increase in fabric extensibility leads to decrease in seam slippage load and seam strength in weft direction. In warp direction, seam slippage load also decreases with increase in fabric weft extensibility, whereas seam strength remains invariant. The results also reveal that the increase in stitch density results in a higher seam slippage load and strength value
Thermal Analysis of Healthy and Ecological Friendly Flame Retardants for Textiles
Flame Retardants (FR) are a group of anthropogenic environmental contaminants used at a relatively high concentration in many applications. Currently, the largest marked group of FRs is halogenated FR, and many of them are considered toxic, persistent and bio accumulative. Non-halogenated alternatives are a possible solution for the problem, but there is a lack of knowledge concerning environmental impact, health risks during the production process and final use. The main objective of the LIFE-FLAREX project that supports this work, is the mitigation of the environmental and human health impact of flame retardants used in textiles, looking for new efficient more ecological and healthy alternatives, able to replace the most common FR’s that include toxic compounds like halogens, formaldehyde and antimony. The aim of this work is to determine the effect of conventional and ecological flame retardants on cotton and polyester fabrics by the application of differential scanning calorimetry DSC and thermogravimetric analysis TGA. Results have been compared with those given by the best FR applied to cotton/polyester blended fabric. The application of DSC up to 550°Cand TGA up to 600°C in N2 and O2 atmospheres give results that are in accordance with those yielded by the micro-scale combustion calorimeter. Onset temperatures of decomposition, steps of loss of mass by temperature and final residues, enable to evaluate the thermal efficiency of the different flame retardants. Results have been compared with those given by the application of ammonium polyphosphate and guanidine phosphate on cotton/polyester 50/50 blend.
Keywords: Thermal Analysis, Flame retardant, Cotton, Polyeste
Effect of different dispersing agents in the non-isothermal kinetics and thermomechanical behavior of PET/TiO2 composites
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 productionPostprint (author's final draft
Aplicació de la microscòpia electrònica de rastreig a l'estudi d'algunes aigües potables a Catalunya
Hom analitza per Microscòpia Electrònica de Rastreig (S.E.M.) les aigües potables de diverses poblacions catalanes: Banyoles, Castelldefels, Molins de Rei, Reus, Tarragona, Valls, el Vendrell, Vilanova i la Geltrú, Sitges, Salou i Vilafranca del Penedès. La preparació de
les mostres fou duta a terme filtrant sota buit mig litre d'aigua a través d'un filtre Nuclepore de 47 mm de diàmetre i 0,2 μm de porus. En cap de les mostres no foren trobades fibres d'asbests. Hom procedí a l'estudi morfològic de les partícules presents en suspensió a l'aigua, i hi troba que les distribucions del nombre de partícules segons la grandària s'ajustaven a les d'una distribució de probabilitats discretes de Poisson. Hom també dugué a terme la caracterització elemental d'aquestes partícules en algunes de les mostres, per microanàlisi de raigs X dispersiva en energies (E.D.X.A.).
Hom analitza per Microscòpia Electrònica de Rastreig (S.E.M.) les aigües potables de diverses poblacions catalanes: Banyoles, Castelldefels, Molins de Rei, Reus, Tarragona, Valls, el Vendrell, Vilanova i la Geltrú, Sitges, Salou i Vilafranca del Penedès. La preparació de
les mostres fou duta a terme filtrant sota buit mig litre d'aigua a través d'un filtre Nuclepore de 47 mm de diàmetre i 0,2 μm de porus. En cap de les mostres no foren trobades fibres d'asbests. Hom procedí a l'estudi morfològic de les partícules presents en suspensió a l'aigua, i hi troba que les distribucions del nombre de partícules segons la grandària s'ajustaven a les d'una distribució de probabilitats discretes de Poisson. Hom també dugué a terme la caracterització elemental d'aquestes partícules en algunes de les mostres, per microanàlisi de raigs X dispersiva en energies (E.D.X.A.)
The Role of SeDeM Characterizing the Active Substance and Polyvynilpyrrolidone Eliminating Metastable Forms in an Oral Lyophilizate - A Preformulation Study.
A preformulation study of an oral lyophilisate with cetirizine dihydrochloride (CTZ) as active ingredient, mannitol and PVP K30 as bulking agents is presented. CTZ shown a humidity content of 0.150% and a spontaneous hygroscopicity of 0.200% (both determined by SeDeM diagram), demonstrating an adequate stability behavior in solid form. A design of experiments (DoE) performed with both mannitol and PVP K30, followed by a simple factorial design (32) has determined the optimum combination of excipients and CTZ, and showed that a higher proportion of PVP K30 was able to prevent metastable forms generated by mannitol
Effect of the presence of an ester of montanic acids with multifunctional alcohols in the composites of titanium dioxide nanoparticles with poly(ethylene terephthalate) in their non-isothermal crystallization
The effect of the addition of an ester of montanic acid with multifunctional alcohols in the effectiveness of the dispersion and compatibility of TiO2 nanoparticles when included as filler in poly(ethyleneterephthalate) for composite production is studied through the study of the non-isothermal crystallization by differential scanning calorimetry (DSC). The application of the Avrami method enables to evaluate the compatibility and the level of dispersion/aggregation of the nanofiller in the poly(ethylene terephthalate) by the analysis of the temperature and enthalpy of crystallization, the kinetic parameters and the half-crystallization timePostprint (author's final draft
Approach to design space from retrospective quality data
Context: Nowadays, the entire manufacturing process is based on the current GMPs, which emphasize the reproducibility of the process, and companies have a lot of recorded data about their processes. Objective: The establishment of the design space (DS) from retrospective data for a wet compression process. Materials and methods: A design of experiments (DoE) with historical data from 4 years of industrial production has been carried out using the experimental factors as the results of the previous risk analysis and eight key parameters (quality specifications) that encompassed process and quality control data. Results: Software Statgraphics 5.0 was applied, and data were processed to obtain eight DS as well as their safe and working ranges. Discussion and conclusion: Experience shows that it is possible to determine DS retrospectively, being the greatest difficulty in handling and processing of high amounts of data; however, the practicality of this study is very interesting as it let have the DS with minimal investment in experiments since actual production batch data are processed statistically
- …