Thermal evaluation of composites from coffee capsules residue with sugarcane bagasse by TG/DTA and DMA

  • PDF / 2,386,093 Bytes
  • 10 Pages / 595.276 x 790.866 pts Page_size
  • 25 Downloads / 170 Views



Thermal evaluation of composites from coffee capsules residue with sugarcane bagasse by TG/DTA and DMA Ana Paula S. Soares1 · Jaqueline S. de Freitas1,2 · Michelle G. Mothé1   · Cheila G. Mothé1 Received: 5 August 2019 / Accepted: 29 June 2020 © Akadémiai Kiadó, Budapest, Hungary 2020

Abstract In this study, new composites were prepared with coffee capsule residue as polymeric matrix reinforced with amounts of 5 or 10% m/m sugarcane bagasse fibers (untreated and treated with 4% NaOH solution). The influence of the bagasse fibers on the thermal properties as well as on the dynamic mechanical behavior of composites was evaluated by Thermogravimetric Analysis (TG), Derivative Thermogravimetry (DTG), Differential Thermal Analysis (DTA) and Dynamic Mechanical Analysis (DMA). TG results of the composites indicated that the thermal stability was influenced by the fiber content. In addition, the alkali fiber treatment decreased the thermal stability of the composites. By the DTA curves, it was possible to assume that polypropylene was the main polymer that constitutes the capsule through the appearance of the melting temperature event. It could be also observed that the samples showed different thermal behavior in the range of 300 and 410 °C due to the fiber content and the use or not of compatibilizer. Based on the results of thermomechanical analysis, it was found that the viscoelastic properties were also influenced by the addition of fiber (untreated or treated) and the presence or absence of compatibilizer. Furthermore, the scanning electron microscopy images of the samples revealed greater adherence between fiber and matrix in the composites that were used compatibilizer. Keywords  Coffee Capsule Residue · Composite · Sugarcane Bagasse · Thermal Analysis

Introduction According to the Brazilian Association of the Coffee Industry (ABIC), the Brazilian consumption of coffee capsules was around 11,000 tons in 2018, and the trend is for this number to grow to 14,000 tons by 2021. Diversity of flavors options, ease of preparation and quality of the product are main factors that stimulated the growth of coffee capsule consumption in the last five years. Therefore, there is a great concern about the management of these residues and consequently, the reduction of the environmental impact.

Cheila G. Mothé in memoriam * Michelle G. Mothé [email protected] 1

Department of Organic Processes, School of Chemistry, Federal University of Rio de Janeiro, Rio De Janeiro, RJ 21941909, Brazil

Federal Institute of Education, Science and Technology of Rio de Janeiro, Rio De Janeiro, RJ 21715000, Brazil


In Brazil, the recycling of coffee capsules reached in 2018, 17.6% of total capsules used [1]. The scientific community has been searching sustainable options for synthetic polymers residues by adding natural fibers, as sugarcane bagasse, in the polymeric matrix in order to generate high value-added products. Karim et al. [2] performed a study about the effect of the bagasse fiber loading on physical and mechanical propertie