Materiales provenientes del reciclamiento de envases de Tetra Pak y su uso en concreto

Son escasos los estudios que involucran el uso de los materiales de reciclo de envases de Tetra Pak. No obstante, se ha estudiado la viabilidad del uso de polietleno de baja densidad (LDPE) y el aluminio reciclados de envases Tetra Pak para la fabricación de tableros rígidos utlizando una prensa caliente. En este capítulo se evaluó el efecto de las partículas de Tetra Pak en concretos poliméricos. Se realizaron ensayos de compresión y fexión, así como el cálculo del módulo de Young; con la finalidad de conocer el efecto de las partículas en la deformación

Aplicación de radiación gamma, como fuente alternativa ambientalmente amigable, sobre películas de aluminio-polietileno para lograr la separación de las mismas

Una de las tantas ventajas que ofrece la radiación gamma, es ser una tecnología ambientalmente amigable, basada en la desintegración de isótopos radiactivos con tiempos de vida de años. Con este tipo de energía ionizante se han podido modificar estructuralmente diferentes tipos de materiales, incluidos los polímeros y los metales. Modificaciones que han permitido tener un uso final tecnológico. En la presente investigación se trabajo con envases de Tetra Pak, los cuales constan de seis capas, constituidas por cuatro de polietileno, una de aluminio y una de papel (celulosa). Siendo 70% de celulosa, 25% de polietileno y 5% de aluminio. En la etapa inicial se separó la celulosa del polietileno-aluminio mediante el proceso de hidropulpado, al material polietileno-aluminio se le conoce como “polialuminio”: Posteriormente se lavo y seco el polialuminio. Este material junto con la celulosa reciclada fueron puestos en diferentes viales por separado, y etiquetados con las diferentes dosis de radiación a los cuales fueron sometidos. Se emplearon dosis entre 50 y 400 kGy

Waste and recycling materials used in concrete

Materials with higher strength and high performanceprovide excellent benefits. But after a very short useful-life become waste and contribute to environmental degradation. Some investigations are focused on recycling by using innovative and clean technologies. In this work, waste and recycled materials as well as gamma radiation are proposed as tools for improving mechanical properties of concrete; polyethylene terephthalate of bottles, automotive tire rubber as well as cellulose of Tetra Pak packages are studied as materials.Autonomous University of the State of Mexico (UAEM), Grant 3886/2015F

Waste materials from Tetra Pak packages as reinforcement of polymer concrete

In this work, different concentrations (from 1 to 6 wt%) and sizes (0.85, 1.40 and 2.36 mm) of waste Tetra Pak particles replaced partially silica sand in polymer concrete. As is well known Tetra Pak packages are made up of three raw materials: cellulose (75%), low-density polyethylene (20%) and aluminum (5%). The polymer concrete specimens were elaborated with unsaturated polyester resin (20%) and silica sand (80%), and irradiated by using gamma rays at 100 and 200 kGy. The obtained results shown that compressive and flexural strength as well as modulus of elasticity decrease gradually, when either Tetra Pak particle concentration or particle size is increased, as regularly occurs in composite materials. Nevertheless, improvements of 14% on both compressive strength and flexural strength, as well as 5% for modulus of elasticity were obtained when polymer concrete is irradiated

Materiales reciclados de llantas automotrices y la radiacion gamma en el mejoramiento del concreto

El concreto es uno de los materiales más importantes dentro de la industria de la construcción, esto se debe no solo a su costo sino a las propiedades que presenta como su fácil colocación antes del fraguado, su resistencia al intemperismo, su durabilidad y resistencia. En aras de reducir el impacto ecológico que genera la producción de cemento, se han hecho esfuerzos por disminuir el consumo de recursos naturales no renovables en la fabricación del concreto. En este capítulo se presenta como opción viable para la solución al problema causado por llantas de desecho su reuso en el concreto como sustituto del agregado fino o grueso, procurando la calidad del producto e incrementando las propiedades deseables como la resistencia, el módulo de elasticidad y la durabilidad

Waste tire particles and gamma radiation as modifiers of the mechanical properties of concrete

In polymer reinforced concrete, the Young’s modulus of both polymers and cement matrix is responsible for the detrimental properties of the concrete, including compressive and tensile strength, as well as stiffness. A novel methodology for solving such problems is based on use of ionizing radiation, which has proven to be a good tool for improvement on physical and chemical properties of several materials including polymers, ceramics, and composites. In this work, particles of 0.85mm and 2.80 mm obtained from waste tire were submitted at 250 kGy of gamma radiation in order to modify their physicochemical properties and then used as reinforcement in Portland cement concrete for improving mechanical properties. The results show diminution on mechanical properties in both kinds of concrete without (or with) irradiated tire particles with respect to plain concrete. Nevertheless such diminutions (from 2 to 16%) are compensated with the use of high concentration of waste tire particles (30%), which ensures that the concrete will not significantly increase the cost

Effects on mechanical properties of recycled PET in cement-based composites

Concretes consisting of portland cement (OPC), silica sand, gravel, water, and recycled PET particles were developed. Specimens without PET particles were prepared for comparison. Curing times, PET particle sizes, and aggregate concentrations were varied. The compressive strength, compressive strain at yield point, and Young modulus were determined. Morphological and chemical compositions of recycled PET particles were seen in a scanning electron microscopy. Results show that smaller PET particle sizes in lower concentrations generate improvements on compressive strength and strain, and Young’s modulus decreases when the size of PET particles used was increased

Characterization of recycled polycarbonate from electronic waste and its use in hydraulic concrete: improvement of compressive performance

Artículo asociado a un proyecto de Doctorado en Ciencia de MaterialesTransparency, excellent toughness, thermal stability and a very good dimensional stability make Polycarbonate (PC) one of the most widely used engineering thermoplastics. Polycarbonate market include electronics, automotive, construction, optical media and packaging. One alternative for reducing the environmental pollution caused by polycarbonate from electronic waste (e-waste), is to use it in cement concretes. In this work, physical and chemical characterization of recycled polycarbonate from electronic waste was made, through the analysis by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), energy dispersive spectroscopy (EDS) and scanning electron microscope (SEM). Then cement concrete was made with Portland cement, sand, gravel, water, and this recycled polycarbonate. Specimens without polycarbonate were produced for comparison purposes. The effect of the particle sizes and concentrations of recycled polycarbonate within the concrete, on the compressive strength and density was studied. Results show that compressive strength values and equilibrium density of concrete depend on the polycarbonate particle sizes and its concentrations; particularly the highest compressive strength values were 20% higher than that for concrete without polycarbonate particles. Moreover, morphological, structural and crystallinity characteristics of recycled polycarbonate, are suitable for to be mixed into concret

Recovery and modification of waste tire particles and their use as reinforcements of concrete

Environmental pollution caused by solid wastes is increasing in the last decades; one of these is referred to automotive tires, which are recycled by differentmethods, includingmechanical grinding. One of the most recurrent applications is to use recycled particles as fillers in building materials, as hydraulic concrete. Nevertheless, detrimental values on the mechanical properties are obtained when they are added. For solving these problems, in this work, a novel proposal is to modify the physicochemical properties of the waste automotive tire particles, previously obtained by grinding process, by using gamma irradiation in order to use them as reinforcements of hydraulic concrete. The results show that improvements on the mechanical properties depend of gamma irradiation as well as concentration and size of waste tire particles. Moreover, SEMimages are related to mechanical properties; for instance, rough surface of the tire particles changes when applying irradiation; more smooth surfaces are created, due to the crosslinking of polymer chains.Nevertheless, for higher doses, cracks are observedwhich are produced by scission of the polymer chains

Waste and recycled textiles as reinforcements of building materials

Se describe el panorama del impacto provocado por las fibras textiles provenientes de los pantalones de mezclilla, así como sus diferentes usos una vez recicladas, en particular en los materiales de construcción.Currently the use of composite materials in the construction areas has had a great impact on the society. Mainly, those related with sustainability and environment aspects. Daily proposals aimed at overcoming the properties of traditional materials arise; which includes emergent materials either from waste or recycled products. One of them is related to textile materials, which including fibers such as wool, hemp, linen and cotton. In the last decade, special attention has been focused on the used clothes, which represent a source of raw materials environmentally responsible and economically profitable. Textile materials are discarded daily around the world, representing approximately 1.5% of the generated waste. Blue-jeans are the most used clothing in the world, they are elaborated by one of the most commonly used natural textile fibers, cotton. Textile materials have been reused in different applications, for example, in the production of poor quality wires, crushed to manufacture insulating materials noise and temperature, and as fillers or reinforcements of concrete. In this chapter, different topics are describing, including: a) Environmental impact of textile waste a result of massive consumption of clothing; b) Recycling and resuse of textile waste, and c) Waste and recycled textile materials used as building materials