Thermal analysis and combustion behavior of polyester nonwoven insulation materials for energy-efficient applications

¹ Technical University of Varna, Department of Thermal Engineering, 9010 Varna, Bulgaria
² Varna Free University “Chernorizets Hrabar”, Dep. of Civil Engineering, 9007 Varna, Bulgaria

^* Corresponding author: This email address is being protected from spambots. You need JavaScript enabled to view it.

Abstract

This study examines the thermal behavior and combustion performance of polyester nonwoven insulation materials with different structural characteristics. Three samples, differing in density, bonding technology, and fiber composition, were analyzed using thermogravimetric and differential thermal analysis (TG/DTG/DTA) combined with controlled flame exposure tests. The results show that thermal decomposition occurs within 380-460 °C. Quantitative combustion indicators, including ignition time, flame duration, and residual mass behavior, were additionally evaluated in order to establish a clearer relationship between thermoanalytical characteristics and actual fire performance. Sample 1 exhibits a multi-stage degradation process with DTG peaks at 389 °C and 423 °C, while Samples 2 and 3 show single peaks at 428 °C and 429 °C, indicating faster and more uniform decomposition. Endothermic effects related to melting are observed at 248–261 °C, followed by exothermic reactions associated with oxidative degradation between 361 and 496 °C. Combustion tests confirm that materials with sharper degradation peaks exhibit more intensive burning and faster structural collapse. A clear relationship between thermal analysis and fire behavior is established, supporting the use of thermoanalytical methods for predicting fire performance of insulation materials. The results further demonstrate that bonding technology and structural density significantly influence degradation mechanisms, flame propagation, and structural stability during thermal exposure.