Synthesis and flame-retardant properties of phosphorus-containing polymers based on poly(4-hydroxystyrene)

Abstract

SYNOPSISPhosphorus-containing polystyrene was obtained through incorporating phosphate groups onto poly(4-hydroxystyrene). This was achieved by esterification with diethylchlorophosphate. The phosphorylation was confirmed by IR, 'H-NMR, and 31P-NMR analysis. By varying the feeding ratios of the reactants, the phosphorus content in the polymers could be successfully tailored and gave values of 12.8 to 4.9% by weight. This was further corroborated by elemental analysis. Thermal characteristics and temporal stability of the phosphorylated polymers were evaluated by DSC and TGA. High char yields (64% by weight) and LO1 values of 41 were found for these polymers. Such properties make these polymers useful in flame retardants.

Preparation, flame retardancy, and thermal degradation of epoxy thermosets modified with phosphorous/nitrogen‐containing glycidyl derivative

“…The neat EP is highly combustible, and its LOI value is only 22.0%. It is clear that the higher is the phosphorus content, the higher is the LOI value, which agrees well with previous reports 19. The LOI value of EP/TGICP composite with 10 wt% TGICP is as high as 35.0%, and it can obtain the V‐0 rating in the UL‐94 protocol.…”

“…However, the phosphorus content of these compounds is not very high, so efforts have been made to develop new flame retardant systems for epoxy resins with higher flame retardant efficiency. Some studies indicate that a significant development of flame retardant efficiency is observed when phosphorus and nitrogen are present together in the epoxy resin system 15–19. Therefore, compositions containing two or more flame retardant elements are of interest.…”

A renewable waste material for the synthesis of a novel non-halogenated flame retardant polymer

“…Previous efforts dedicated for the synthesis of non-halogenated FRs were primarily on compounds containing phosphorus (Weil et al, 1999), silicon (Zaikov andLomakin, 1998) and boron (Armitage et al, 1996). Simple co-polymerization of epoxies (Lin et al, 2000), vinyls (Liu et al, 1996) and acrylics (Banks et al, 1994) with phosphate monomers, linear polyphosphazenes and aromatic cyclic phosphazenes (Allen, 1994) are the broad categories of phosphorous containing non-halogenated FRs. Among silicon containing compounds, polymers based on linear silanes/siloxanes (Masatoshi and Serizawa, 1998) and silsesquioxanes (Provatas and Matisons, 1997) are being extensively investigated.…”

Synthesis and properties of a phosphorus-containing flame retardant epoxy resin based on bis-phenoxy (3-hydroxy) phenyl phosphine oxide

“…The cured BPHPPO-EP produced much less fumes than the cured TBBA-EP during combustion. So the flame retardance could be enhanced remarkably by raising the content of phosphorus in the epoxy resins, and when at a similar molar proportion in the compound, the phosphorus element also exhibited much better flame retardancy than the bromine element did [14,17].…”