Belfast School of Architecture and the Built Environment, Ulster University, 2-24 York Street, Belfast BT15 1AP, Northern Ireland, UK.
Institute for Sustainable Industries and Liveable Cities, College of Engineering and Science, Werribee West Campus, Victoria University, P.O. Box 14428, Melbourne, VIC 8001, Australia.
Molecules. 2022 Dec 29;28(1):278. doi: 10.3390/molecules28010278.
Polystyrene (PS) was modified by covalently binding P-, P-N- and/or N- containing fire-retardant moieties through co- or ter-polymerization reactions of styrene with diethyl(acryloyloxymethyl)phosphonate (DEAMP), diethyl--vinylbenzyl phosphonate (DEpVBP), acrylic acid-2-[(diethoxyphosphoryl)methylamino]ethyl ester (ADEPMAE) and maleimide (MI). In the present study, the condensed-phase and the gaseous-phase activities of the abovementioned fire retardants within the prepared co- and ter-polymers were evaluated for the first time. Pyrolysis-Gas Chromatography/Mass Spectrometry was employed to identify the volatile products formed during the thermal decomposition of the modified polymers. Benzaldehyde, α-methylstyrene, acetophenone, triethyl phosphate and styrene (monomer, dimer and trimer) were detected in the gaseous phase following the thermal cracking of fire-retardant groups and through main chain scissions. In the case of PS modified with ADEPMAE, the evolution of pyrolysis gases was suppressed by possible inhibitory actions of triethyl phosphate in the gaseous phase. The reactive modification of PS by simultaneously incorporating P- (DEAMP or DEpVBP) and N- (MI) monomeric units, in the chains of ter-polymers, resulted in a predominantly condensed-phase mode of action owing to synergistic P and N interactions. The solid-state P NMR spectroscopy, Scanning Electron Microscopy/Energy Dispersive Spectroscopy, Inductively-Coupled Plasma/Optical Emission Spectroscopy and X-ray Photoelectron Spectroscopy of char residues, obtained from ter-polymers, confirmed the retention of the phosphorus species in their structures.
聚苯乙烯（PS）通过与二乙基（丙烯酰氧甲基）膦酸酯（DEAMP）、二乙基--乙烯基苯膦酸酯（DEpVBP）、丙烯酸-2-[(二乙氧基膦酰基)甲基氨基]乙酯（ADEPMAE）和马来酰亚胺（MI）的共聚或共-三聚合反应，将 P、P-N-和/或 N-含有的阻燃部分共价键合到 PS 上进行改性。在本研究中，首次评估了上述阻燃剂在制备的共聚物和三聚物中的凝聚相和气相活性。热解气相色谱/质谱法用于鉴定热分解过程中形成的挥发性产物。在阻燃基团的热裂解和主链断裂过程中，在气相中检测到苯甲醛、α-甲基苯乙烯、苯乙酮、三乙基磷酸酯和苯乙烯（单体、二聚体和三聚体）。在 ADEPMAE 改性的 PS 中，由于气相中三乙基磷酸酯可能存在抑制作用，抑制了热解气体的演化。通过在三聚物的链中同时引入 P-（DEAMP 或 DEpVBP）和 N-（MI）单体单元，对 PS 进行反应性改性，由于 P 和 N 的协同相互作用，导致主要为凝聚相作用模式。从三聚物得到的残渣的固态磷 NMR 光谱、扫描电子显微镜/能量色散光谱、电感耦合等离子体/发射光谱和 X 射线光电子能谱证实了磷物种在其结构中的保留。
