Novel phenolic resin hollow microspheres: Flame retardancy and toxicity reduction in thermoplastic polyurethane elastomer

• Published in: Express polymer letters Vol. 15; no. 9; pp. 887 - 898
• Main Authors: Jiao, C. M., Zhang, Y. L., Dong, H. X., Chen, W. J., Liu, W., Li, S. X., Chen, X. L.
• Format: Journal Article
• Language: English
• Published: Budapest Budapest University of Technology and Economics, Faculty of Mechanical Engineering, Department of Polymer Engineering 01-09-2021; Budapest University of Technology
• Subjects: Cone calorimeters; Epoxy resins; flame retardancy; Flame retardants; Fourier transforms; Green chemistry; Heat release rate; Heat resistance; Infrared analysis; Infrared spectroscopy; Microspheres; Phenolic resins; Phenols; Polymers; Polyurethane resins; Raman spectroscopy; Reduction; Scanning electron microscopy; Scientific imaging; thermal properties; Thermogravimetric analysis; thermoplastic polyurethane elastomer; Toxicity; toxicity reduction; Urethane thermoplastic elastomers; China; Japan
• ISSN: 1788-618X; 1788-618X
• DOI: 10.3144/expresspolymlett.2021.71

In this paper, phenolic resin hollow microspheres (PHM) were prepared using in-situ polymerization and used as flame-retardants for TPU. The structure and composition of PHM were characterized by Scanning Electron Microscope (SEM). The potential of PHM as flame retardant was verified by thermogravimetric analysis (TG). Then, the flame retardancy and toxicity reduction of PHM in TPU/PHM composites were verified by cone calorimeter test (CCT) and Thermogravimetric Analysis-infrared Spectrometry (TG-IR). It has been found that comparing TPU/PHM-4 sample containing 4.0 wt% PHM with pure TPU, the peak heat release rate (pHRR) was reduced by 61.6%, the total smoke release (TSR) by 23.2%, and the CO production by 86.2%, respectively. The SEM, Laser Raman Spectroscopy Test (LRS), and other tests were carried out to test the char residues after CCT, and the mechanism of PHM in the process of flame retardant TPU was reasonably deduced. In a word, PHM is very effective as a flame retardant of TPU.