Phosphinated phenols from acid‐fragmentation of bisphenols and their unsymmetrical diamine derivatives for copolyimides

Abstract

Four novel diamines (9–12) were prepared by a two‐step procedure from phosphinated phenols (1–4) that were prepared from acid‐fragmentation of four bisphenols, including bisphenol A, 4,4′‐isopropylidenebis(2,6‐dimethylphenol), cis(4‐hydroxyphenyl)cyclohexane, and 9,9′‐bis(4‐hydroxyphenyl)fluorene, followed by nucleophilic addition of 9,10‐dihydro‐oxa‐10‐phosphaphenanthrene‐10‐oxide (DOPO). Copolyimides based on (9–12)/4,4′‐diaminodiphenyl ether (ODA)/dianhydride were prepared. The structure‐property relationship on the copolyimides was discussed. Due to the structural similarity, (9)/ODA‐based copolyimides were compared with (10)/ODA‐based copolyimides, while (11)/ODA‐based copolyimides were compared with (12)/ODA‐based copolyimides. The dimethyl substitutents cause (10)/ODA‐based copolyimides to display higher Tg, modulus, dimensional stability, contact angle, and better solubility than (9)/ODA‐based copolyimides. (12)/ODA‐based copolyimides that exhibit fluorene moieties display higher Tg and thermal stability, but a lower contact angle and poorer solubility than (11)/ODA‐based copolyimides that exhibit cyclohexane moieties. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 390–400

Synthesis of a heat‐resistant DOPO derivative and its application as flame‐retardant in engineering plastics

“…DOPO derivatives are often used as reactive flame retardants and the resulted resins are called intrinsically flame‐retardant materials. The common means to introduce DOPO structure into polymer chains was using DOPO derivatives as a hardener in epoxy resin or as a co‐monomer in polyester . Xie and Gao synthesized a curing agent through DOPO, aniline, and 4‐hydroxybenzaldehyde, used it in combination with 4,4′‐diaminodiphenylmethane to co‐cure epoxy resin, and got an improvement of char yield from 21% to 27% and LOI from 24.5% to 33.5%.…”

Phosphorus-containing polymers from THPS.I. Design, synthesis, and characterization of novel monomer and polyureas

“…[25,26] However, white phosphorus is toxic and pyrophoric, and in fact, it is not available through standard chemical suppliers and is typically converted on site into other compounds. Part of phosphorus-containing monomers and polymers rely on PCl 3 , such as DOPO and its derivatives, [25][26][27] arylphosphoric dichloride [20,28] and phosphorus-containing acylchloride. [29][30][31] Since reactive phosphorus-chlorine bond is not necessary in most polymers, it is desirable to avoid the use of chlorine altogether.…”