TY - JOUR
T1 - Behavior and mechanism of flame retardant epoxy resins with intrinsic phosphorus-nitrogen phenolic resin curing agents
AU - Yuan, Lailai
AU - Yang, Zhi
AU - Zeng, Panjin
AU - Gao, Tong
AU - Lv, Yuelin
AU - Liu, Xiaochen
AU - Ou, Ye
AU - Chen, Lixin
N1 - Publisher Copyright:
© 2024 Elsevier Ltd
PY - 2024/4/24
Y1 - 2024/4/24
N2 - In this paper, two phosphorus-nitrogen phenolic resins (DPO-PR, DOPO-PR) were synthesized from phenol, paraformaldehyde, dicyandiamide, DOPO, and diphenylphosphine oxide (DPO) as raw materials as curing agents and were applied in epoxy resins. The structures of DPO-PR and DOPO-PR were characterized by FTIR, 1H NMR and 31P NMR. In the TGA test, the decomposition temperature of DPO-PR/EP and DOPO-PR/EP decreased, but the residue yield increased substantially. DPO-PR/EP had a higher LOI value than DOPO-PR/EP at the same addition amount. Compared with PR/EP, DPO-PR/EP showed that pk-HRR decreased by 41.5 %, THR decreased by 29.4 %, and a slight increase in residue yield. DPO-PR/EP and DOPO-PR/EP were analyzed by TG-MS, and the results showed that both DPO-PR/EP and DOPO-PR/EP can decompose phosphorus free radicals to exert quenching effects. Characterization of the char layer by SEM and XPS showed that DPO-PR and DOPO-PR were able to produce phosphoric acid substances to promote the dehydration of the epoxy resin into char layer, enhance the integrity of the char layer of the epoxy resin, and effectively exert the shielding and barrier effect.
AB - In this paper, two phosphorus-nitrogen phenolic resins (DPO-PR, DOPO-PR) were synthesized from phenol, paraformaldehyde, dicyandiamide, DOPO, and diphenylphosphine oxide (DPO) as raw materials as curing agents and were applied in epoxy resins. The structures of DPO-PR and DOPO-PR were characterized by FTIR, 1H NMR and 31P NMR. In the TGA test, the decomposition temperature of DPO-PR/EP and DOPO-PR/EP decreased, but the residue yield increased substantially. DPO-PR/EP had a higher LOI value than DOPO-PR/EP at the same addition amount. Compared with PR/EP, DPO-PR/EP showed that pk-HRR decreased by 41.5 %, THR decreased by 29.4 %, and a slight increase in residue yield. DPO-PR/EP and DOPO-PR/EP were analyzed by TG-MS, and the results showed that both DPO-PR/EP and DOPO-PR/EP can decompose phosphorus free radicals to exert quenching effects. Characterization of the char layer by SEM and XPS showed that DPO-PR and DOPO-PR were able to produce phosphoric acid substances to promote the dehydration of the epoxy resin into char layer, enhance the integrity of the char layer of the epoxy resin, and effectively exert the shielding and barrier effect.
KW - Epoxy resin
KW - Flame retardant
KW - Quenching effect
KW - Shielding and blocking effect
UR - http://www.scopus.com/inward/record.url?scp=85189015166&partnerID=8YFLogxK
U2 - 10.1016/j.eurpolymj.2024.112959
DO - 10.1016/j.eurpolymj.2024.112959
M3 - 文章
AN - SCOPUS:85189015166
SN - 0014-3057
VL - 210
JO - European Polymer Journal
JF - European Polymer Journal
M1 - 112959
ER -