This work reveals a facile, one-pot synthesis of phosphinated bisphenols (1–2) from a nucleophilic addition of 9,10-dihydro-9-oxa-10-phosphaphenanthrene 10-oxide (DOPO) to diaminophenylmethane- and diaminophenylether-based benzoxazines (P-ddm and P-oda). A reaction mechanism including active hydrogen abstraction, ring-opening, and nucleophilic addition was proposed for the synthesis. Phosphinated dicyanate esters (3–4) were prepared based on bisphenols (1–2), and were copolymerized with a commercially available dicyanate ester of bisphenol A (BACY). The properties such as glass transition temperature, coefficient of thermal expansion, thermal decomposition temperature, water absorption, and flame retardancy of the resulting thermosets were evaluated. Experimental data show that incorporating (3–4) into BACY enhances the flame retardancy, dimensional stability and dielectric properties with small penalty to the thermal properties. A thermoset with Tg 241 C, CTE 50 ppm per C, Dk 3.01 (1 GHz), Td (5%), N2: 407 C, and UL-94 V-0 rating can be achieved via this approach

Three aromatic diamine‐based, phosphinated benzoxazines (7–9) were prepared from three typical aromatic diamines—4,4′‐diamino diphenyl methane (1), 4,4′‐diamino diphenyl sulfone (2), and 4,4′‐diamino diphenyl ether (3) by a one‐pot procedure. To clarify the reaction mechanism, a two‐pot procedure was applied, in which the reaction intermediates (4–6) were isolated for characterization. The structures of intermediates and benzoxazines were confirmed by high resolution mass, IR, and 1D and 2D‐NMR spectra. In addition to self‐polymerization, (7–9) were copolymerized with cresol novolac epoxy (CNE). After curing, the homopolymers of P(7–9) are brittle while the copolymers of (7–9)/CNE are tough. Dynamic mechanical analysis shows the Tgs of (7–9)/CNE copolymers are 187, 190, and 171 °C, respectively. Thermal mechanical analysis shows the CTEs of (7–9)/CNE copolymers are 46, 38, and 46 ppm, respectively. All the (7–9)/CNE copolymers belong to an UL‐94 V‐0 grade, demonstrating good flame retardancy. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010

Generally, protection and deprotection procedures of amino groups are required in preparing propargyl ether-containing benzoxazines. In this study, we report a facile, deprotection-free preparation of a propargyl ether-containing phosphinated benzoxazine (2) from the nucleophilic substitution of a phenolic OH-containing phosphinated benzoxazine (1) and propargyl bromide in the catalysis of potassium carbonate. The structure of (2) was characterized and confirmed by a high-resolution mass spectrum, 1H, 13C, 1H-1H, 1H-13C nuclear magnetic resonance (NMR) spectra, and X-ray single crystal diffractogram. infrared (IR) and differential scanning calorimetry were used to monitor the ring-opening of benzoxazine and crosslinking of propargyl ether. The microstructure and the structureproperty relationship of the resulting homopolymers and copolymers are discussed. The Tg of homopolymer of (2) is 208 degrees C by dynamic mechanical analysis, the coefficient of thermal expansion is 43 ppm/degrees C, and Td 5% (N2) is 393 degrees C, respectively, which are higher than those of the homopolymer of (1). Similar trends were observed in the copolymerization system. The results demonstrate the beneficial effect of crosslinking afforded by the propargyl ether group is higher than that by the phenolic OH group. (C) 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 201

We reveal a route for the preparation of phosphinated bisphenol, 1,1-bis(4-hydroxyphenyl)-1-(6-oxido-6H-dibenz <1,2> oxaphosphorin-6-yl)ethane (2), via a one-pot reaction of 1,1,1-tris(4-hydroxyphenyl)ethane and 9,10-dihydro-9oxa-10-phosphaphenanthrene 10-oxide (DOPO) in the catalysis of p-toluenesulfonic acid. A two-step reaction mechanism, acid-fragmentation of 1,1,1-tris(4-hydroxyphenyl)ethane followed by nucleophilic addition of DOPO, is proposed for the synthesis. Based on (2), a dicyanate ester derivative, 1,1-bis(4cyanatophenyl)-1-(6-oxido-6H-dibenz <1,2> oxaphosphorin-6-yl)ethane (3) was prepared and co-cured with a commercially available dicyanate ester, the dicyanate ester of bisphenol A (BACY). Experimental data show that incorporating (3) into BACY enhances the flame retardancy and dielectric properties with little penalty to the thermal properties. A thermoset with T g 274 C, coefficient of thermal expansion (CTE) 49 ppm/ C, D k 3.04 (1 GHz), T d (5%,) N 2 : 435 C, air: 424 C, and UL-94 V-0 rating can be achieved via this approach.

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