Tris 3-aminophenyl Phosphine Oxide Research Articles

Flame-retardant halogen-free polymers using phosphorylated hexaglycidyl epoxy resin

Flame-retardant halogen-free epoxy resin, containing phosphorus and nitrogen atoms in the main chain, was synthesized through the curing of tris(3-(bis(oxiran-2-ylmethyl)amino)phenyl)phosphine oxide (HGE, hexaglycidyl epoxy monomer), starting from tris(3-aminophenyl) phosphine oxide (TAPO) and epichlorohydrin. The molecular structure of HGE with molecular weight 660 was confirmed using Fourier transform infrared, nuclear magnetic resonance, and liquid chromatography–mass spectrometry techniques. Epoxy equivalent weight determined by titration method was 120. The thermal curing behavior of the HGE/TAPO was investigated by differential scanning calorimetry. An intense exotherm due to curing reaction was observed in the temperature range from 123°C to 215°C. The HGE cured with TAPO, 4,4′-diaminodiphenylsulfone (DDS), and 1,5-diaminonaphthalene (DAN) and the thermal behaviors were studied by thermogravimetric analysis. The flame retardancy properties of the HGE/TAPO, DDS, and DAN were evaluated by vertical burning test (UL-94 V). The high performance cured epoxy resins showed high thermal stability and UL-94 V-0 flame retardancy rating.

Synthesis, characterization of phosphorus containing diamide-diimide-tetraamines based on L-tryptophan amino acid and their effect on flame retardancy of epoxy resins

The curing behavior of diglycidyl ether of bisphenol-A (DGEBA) with different phosphorus containing diamide-diimide-tetraamines (DADITAs) was studied by DSC. Eight DADITAs of varying structures were synthesized by reacting 1 mole of pyromellitic anhydride (PMDA)/3,3′-benzophenone tetracarboxylic dianhydride (BTDA)/1,4,5,8-naphthalene tetracarboxylic dianhydride (NTDA)/4,4′-oxydiphthalic anhydride (ODPA) with 2 mole of L-tryptophan (T) in a mixture of acetic acid and pyridine (3:2 V/V) followed by activaton with thionyl chloride and then condensation with excess of phosphorus containing triamines tris(3-aminophenyl) phosphine (TAP) and tris(3-aminophenyl) phosphine oxide (TAPO). DADITAs obtained by reacting PMDA/BTDA/NTDA/ODPA with L-tryptophan followed by condensation with TAP/TAPO were designated as PTAP, PTAPO, BTAP, BTAPO, NTAP, NTAPO, OTAP and OTAPO respectively. The structural characterization of synthesized DADITAs was done by FTIR, 1H-NMR, 13C-NMR, 31P-NMR spectroscopic techniques and elemental analysis. Thermal stability of the isothermally cured epoxy was investigated using dynamic thermogravimetry analysis. The glass transition temperature (T g) was highest in DGEBA cured using PTAP. All epoxy thermosets exhibited excellent flame retardancy, moderate changes in T g and thermal stability. Due to presence of phosphorus in curing agents, all epoxy resin systems met the UL-94 V-0 classification and the limiting oxygen index (LOI) reached up to 38.5, probably because of the nitrogen-phosphorus synergistic effect.

Curing and thermal behaviour of a flame retardant cycloaliphatic epoxy resin based on phosphorus containing poly(amide–imide)s

The curing behaviour of 3,4-epoxycyclohexylmethyl 3,4-epoxycyclohexane carboxylate was investigated by the dynamic differential scanning calorimetry (DSC) using phosphorus-containing poly(amide–imide)s (PAIs) having free amine groups, 4,4′-diaminodiphenylmethane (PM) and p-phenylenediamine (PA), in the ratio of 1:1. The PAIs were prepared by co-polymerization of diimide–diacid (DIDA) and phosphorus-containing triamines having phenylene moiety. l-Tryptophan and pyromellitic anhydride were used to synthesize DIDA. Triamines used in the synthesis PAIs were tris(3-aminophenyl) phosphine (TAP), tris(3-aminophenyl) phosphine oxide (TAPO) and bis(3-aminophenyl) aminotolyl phosphine (BAP). TAP-, TAPO- and BAP-containing PAIs were designated as PTAP, PTAPO and PBAP, respectively. These PAIs with free amine groups were characterized by FTIR, 1H NMR, 13C NMR spectroscopic techniques and elemental analysis. The mixture of PAIs and PM or/and PA in the ratios of 0:1, 1:0 and 0.5:0.5 was used for investigation. DSC was used to study the curing of epoxy by recording the DSC scans at heating rates of 10 °C min−1. Thermal stability of epoxy resin cured isothermally was evaluated by recording thermo gravimetric traces in nitrogen atmosphere at the heating rate of 20 °C min−1. All samples are highly stable, and the 10 % mass loss found was in the range of 335–520 °C. The percent char yield was highest in case of resin sample E/PM/PTAPO. The flame-retardant properties of cured epoxy resins were investigated by the limiting oxygen index test (LOI) and UL94 test. When phosphorus was incorporated in epoxy resin, the epoxy resin system met the UL94 V-0 classification and the LOI reached at 37.8, because of nitrogen–phosphorus synergistic effect.

Preparation and characterization of hyperbranched polyaspartimides from bismaleimides and triamines

AbstractHyperbranched polyaspartimides were successfully prepared from bismaleimides (A2) and triamines (B3) through the Michael addition reaction. Two bismaleimides of 4,4′‐bismaleimidodiphenylmethane (BMDM) and bis(3‐ethyl‐5‐methyl‐4‐ maleimidophenyl)methane (BEMM) and two triamines of tris(3‐aminophenyl)phosphine oxide (TAPPO) and tris(4‐aminophenyl)amine (TAPA) were employed in the preparation of these hyperbranched polyaspartimides. The chemical structures of the polymers were characterized with Fourier transform infrared (FTIR), 1H and 31P NMR, and elemental analysis. Degrees of branching ranging from 0.51 to 0.69 were found with the polyaspartimides, ensuring their hyperbranched structure. The polymers also showed good solubility in common solvents, high glass‐transition temperatures of 256 °C, and excellent thermal stability above 370 °C. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 5921–5928, 2004

Syntheses, structure, reactivity, and thermal properties of epoxy–imide resin cured by phosphorylated triamine

A new phosphorylated epoxy–imide polymer was obtained using diimide–diepoxide (DIDE) cured with tris(3-aminophenyl)phosphine oxide (TAPO). In addition, compositions of the synthesized diimide diepoxide (DIDE), Epon 828, and DEN 438 with common curing agents, e.g., 4,4′-diaminodiphenyl ether (DDE) and 4,4′-diaminodiphenylsulfone (DDS), were compared as to curing reactivity and heat and flame retardation with that of tris(3-aminophenyl)phosphine oxide. The reactivities of those curing agent toward the three kinds of epoxy resins, as measured by differential scanning calorimetry (DSC), were in the order DDE > TAPO > DDS. Through thermal gravimetric analysis (TGA), the thermal and flame resistances of epoxy were confirmed in this study as capable of being significantly improved through introduction of imide and phosphorus groups into the epoxide structure. © 1996 John Wiley & Sons, Inc.

Phosphorus-containing crosslinkable polymers for fire- and heat-resistant applications

New phosphorus-containing polyimides, polyamides and polyureas with saturated and unsaturated imide pendant groups were synthesized and characterized. Their synthesis was based on the monoamic acid derived from the reaction of tris(3-aminophenyl)phosphine oxide (TAPO) with an equimolar amount of succinic/maleic/nadic/itaconic anhydride. It was reacted subsequently with an equimolar amount of pyromellitic dianhydride (PMDA) or terephthaloyl chloride or tolylene diisocyanate. The crosslinkable polymers gave a network structure by curing at 230–260°C for 2.5 hr. Their thermal behaviour was investigated by DTA and TGA. All cured resins were stable up to 302–377 and 302–375°C in nitrogen and air, respectively. The char yield at 800°C in nitrogen was 51–75%. The physical and thermal properties depended on chemical structure.