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Diglycidyl ether of bisphenol A (DGEBA) was cured with a new phosphorus-containing diamine, 1,4-bis(3-aminobenzoyloxy)-2-(6-oxido-6H-dibenz͗c,e͗͘1,2͘oxa-phosphorin-6-yl)phenylene II, which was derived from 2-(6-oxido-6H-dibenz͗c,e͗͘1,2͘-oxaphosphorin-6-yl)-1,4-dihydroxy phenylene and 3-nitrobenzoyl chloride followed by hydrogenation. The structure of the synthesized phosphorus-containing curing agent II was confirmed through EA, IR, 1 H-NMR, and 31 P-NMR. The curing kinetics of the DGEBA/II system were studied by the dynamic and isothermal DSC method. Dynamic kinetic parameters were calculated by using the Kissinger and Ozawa's methods, respectively. Isothermal kinetic parameters, including k 1 , k 2 , m, and n, were determined by an autocatalytic mechanism proposed by Kamal. The model gives a good description of curing kinetics up to the onset of vitrification. The glass transition temperatures of cured epoxy (DGEBA/II) were 180°C based on DMA and 170°C by DSC, respectively. The onset decomposition temperatures (T d onset) were 376 and 367°C under nitrogen and air, respectively. Char yields at 700°C were 38 and 18% under nitrogen and air, respectively. Limiting oxygen index (LOI) was 30, thus the phosphorus-containing diamine curing agent II was found to impart flame retardancy to the cured epoxy resin.

A series of phosphorous‐containing aliphatic polyesters were synthesized by high‐temperature solution condensation of 2‐(6‐oxido‐6H‐dibenz〈c,e〉〈1,2〉oxaphosphorin‐6‐yl)‐1,4‐hydroxyethoxy phenylene (III) with various aromatic acid chlorides in o‐dichlorobenzene. All polyesters are amorphous and readily soluble in many organic solvents such as DMAc, NMP, DMSO, and o‐dichlorobenzene at room temperature or upon heating. These polyesters are thermally quite stable. The glass transition temperatures of these aliphatic polyesters ranged from 126.6 to 162.2°C. The degradation temperatures (Td onset) in nitrogen ranged from 424 to 448°C, and the char yields at 700°C are 20–32%. The activation energies of degradation ranged from 160.9 to 226.0 kJ/mol. The LOIs of these polyesters ranged from 36 to 43. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 3051–3061, 1998

A series of advanced epoxy resins with various epoxy equivalent weights were synthesized from a reactive phosphorus-containing diol, 2-(6-oxido-6H-dibenz[c,e][1,2]oxaphosphorin-6-yl)-1,4-dihydroxy phenylene and diglycidyl ether of bisphenol A and then cured with 4,4Ј-diaminodiphenyl sulfone, phenol novolac, or dicyandiamide. The parameters of the polymerization reaction (such as reaction time, catalyst) are discussed in this article. Thermal properties of cured epoxy resins were studied using differential scanning calorimetry, dynamic mechanical analysis, and thermal gravimetric analysis. The flame retardancy of cured epoxy resins was tested by limiting oxygen index. The relations between thermal properties, flame retardancy, and epoxy equivalent weights were also studied.