Obtención de nanoestructuras de celulosa por electrospinning a partir del papel tissue no conforme

Abstract

La celulosa es la biomolécula orgánica más abundante en el planeta. Este biopolí- mero compuesto por largas cadenas de 𝜷−𝒈𝒍𝒖𝒄𝒐𝒔𝒂 hace parte fundamental de los procesos productivos de la industria del papel, ya que mediante su transformación desde fibra virgen o reciclada se obtiene una amplia variedad de productos del mer- cado conocidos como papel tissue: papel higiénico, toallas, servilletas, pañuelos fa- ciales, entre otros. Una empresa local de la zona dedicada a la fabricación de estos productos durante los últimos años ha presentado un significativo rechazo diario de papel tissue (alrededor de 2 toneladas) debido a condiciones fuera de especifica- ciones o de proceso. En consecuencia, se obtienen grandes cantidades de papel sin otro destino que ser reintegrado al proceso como materia prima. Si se tiene en cuenta que este material de rechazo actualmente es usado como componente fibroso, y que su costo oscila entre 2 y 5 veces el de la materia prima tradicional, nace la necesidad de evaluar nuevas formas de aprovechamiento para este rechazo con alto contenido de celulosa, en búsqueda de materiales con importantes propiedades fisicoquímicas y mecánicas, que puedan ser usados en aplicaciones de mayor valor para la compañía.

Cellulose is the most abundant organic biomolecule on the planet. This biopolymer composed of long chains of 𝜷 − 𝒈𝒍𝒖𝒄𝒐𝒔𝒂 is a fundamental part of the production processes of the paper industry, since through its transformation from virgin or recycled fiber, a wide variety of market products known as tissue paper is obtained: toilet paper, towels, napkins, facial tissues, among others. A local company in the area dedicated to the manufacture of these products presents a significant daily re jection of tissue paper (around 2 tons) due to out of specification or process condi tions. Consequently, large quantities of paper are obtained with no other destination than to be reintegrated into the process as raw material. If it is taken into account that this rejection material is currently used as a fibrous component, and that its cost ranges between 2 and 5 times that of the traditional raw material, the need arises to evaluate new forms of use for this rejection with a high content of cellulose, in search of materials with important physicochemical and mechanical properties that can be used in applications of greater value to the company. Now, obtaining cellulose nanostructures is an interesting alternative: they are biopolymers with characteristics and properties that are particularly useful for this industry, due to their structure, high porosity, surface area, low weight and increases in tensile strength. One method of obtaining these nanostructures is electrospinning, a versatile technique, and widely used today, in which from a polymeric solution, fine materials of different sizes are obtained. However, to obtain satisfactory results, the solution should show specific properties, including high solubility and low viscosity. This has been an important challenge for obtaining cellulose nanostructures in industry for several years, since the direct processing of cellulose is difficult due to its strong intermolecular hydrogen bonding, which affects the solubility in conventional solvents and low environmental impact. In this study, a methodology for the manipulation of the cellulose of the tissue paper was implemented. Different solvents were tested, resulting as the best one aqueous type at 7 wt% NaOH and 12 wt% urea with a low toxic level compared to other conventional solvents, allowing the obtaining of cellulose nanostructures in electrospinning, these nanostructures were incorporated into recycled paper manu factured at the laboratory level, allowing a increase in tensile strengths between 18 and 44%. This valorization allowed obtaining a material with better mechanical char acteristics, when 1 to 4% cellulose nanostructure was applied, generating a contri bution to knowledge in the paper industry.