KUI , Chengyu. Research Progress in Halogen-Free Flame Retardant Rigid Polyurethane Foam. Transactions on Engineering and Technology Research, [S. l.], v. 2, p. 117–133, 2024. DOI: 10.62051/180pmr30. Disponível em: https://wepub.org/index.php/TETR/article/view/2719. Acesso em: 24 may. 2026.