Phenylphosphine Oxide Research Articles

Phosphorus‐containing polyhedral oligomeric silsesquioxane/polyimides hybrid materials with low dielectric constant and low coefficients of thermal expansion

ABSTRACTNovel phosphorus‐containing polyhedral oligomeric silsesquioxane (POSS)/polyimides (PI) hybrid materials with low dielectric constant and low linear coefficients of thermal expansion (CTE) were prepared and characterized. The POSS/PI hybrid materials were synthesized with octa(aminopropyl)silsesquioxane (OAPS) and a series of phosphorus‐containing polyamide acids(PAA). The PAAs were synthesized with bis(4‐aminophenoxy) phenyl phosphine oxide (BAPPO), 4,4’‐diaminodiphenyl ether (ODA) and 3,3',4,4'‐biphenyl tetracarboxylic diandhydride (BPDA). The structures and properties of the hybrid materials were characterized. And the effect of the phosphorus‐containing structure on the POSS/PI hybrid materials was discussed. The dielectric constants and CTE of the hybrid materials were remarkably lower than that of the unmodified POSS/PI films. The lowest values of dielectric constant and CTE could achieve as low as 2.64 (1 MHz) and 27.45 ppm/K. Besides, the hybrid materials also had excellent thermal properties. The highest 5% weight loss temperature of the hybrid materials was as high as 580°C under air. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42611.

Thermal, mechanical and structural investigation of copolyimide–silica hybrids containing phosphine oxide

Abstract In this study, a novel hybrid copolyimide was synthesized from copolyamic acid solutions (PAAs) obtained by the reaction between bis(3-aminophenoxy-4-phenyl)phenylphosphine oxide ( m -BAPPO), 3,3′-diaminodiphenyl sulfone (DDS) and 3,3′,4,4′-benzophenone tetracarboxylic dianhydride (BTDA), followed by thermal imidization. Hybrid materials containing 5% SiO 2 were synthesized by sol–gel technique. The polyimide–silica hybrids were characterized by Fourier Transform Infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). Thermogravimetric analysis showed that the weight loss of hybrids is shifted to the higher temperature compared to the neat copolyimide. The contact angle measurements confirmed the hydrophobic surface of hybrids. Moreover, the gas permeability measurements were also done to take a step for forthcoming gas separation studies. The tensile modulus and strength of the copolyimides are good.

Structural effect of monomer type on properties of copolyimides and copolyimide-silica hybrid materials

In this work, the effect of two different diamine monomers, containing phosphine oxide, on thermal, mechanical and morphological properties of copolyimides and their hybrid materials was investigated. Gas separation properties of the synthesized copolyimides were also analysed. Two different diamine monomers with phosphine oxide were bis(3-aminophenyl) phenylphosphine oxide (BAPPO) and bis(3-aminophenoxy-4-phenyl) phenylphosphine oxide (m-BAPPO). In the synthesis of copolyimides 3,3?-diamino-diphenyl sulfone (DDS) was also used as the diamine, as well as 2,2?-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride (6FDA). Copolyimide films were prepared by thermal imidization. Hybrid materials containing 5 % SiO2 were synthesised further by sol-gel technique. The Fourier-transform infrared spectroscopy (FTIR), Nuclear magnetic resonance spectroscopy (NMR) confirmed the expected structure. Dynamic mechanical analysis (DMA) demonstrated that m-BAPPO based copolyimides had lower glass transition temperatures (Tg) than BAPPO based copolyimides. m-BAPPO containing copolyimide without silica shifted the thermal decomposition temperature to a higher value. The moduli and strength values of BAPPO diamine containing copolyimide and its hybrid were higher than those of m-BAPPO containing materials. The contact angle measurements showed the hydrophobicity. Scanning electron microscope (SEM) analysis exhibited the silica particles dispersion in the copolyimides. These copolyimides may be used in the coating industry. The CO2 permeability and the permselectivity were the highest among the other values in this study, when m-BAPPO containing copolyimide in the absence of silica was used. The gas permeabilities obtained from this work were in this decreasing order: PCO2 > PO2 > PN2.

Application of bis(glycidyloxy)phenylphosphine oxide as a chain extender for polyamide-6

Figure melt torque of PA6 mixed with different contents of chain extender BGPPO. The addition of small molecule diepoxide (BGPPO) greatly enhanced the melt torque, rheological and mechanical properties of polyamide-6 through chain extension reaction.

Atomic oxygen resistant phosphorus-containing copolyimides derived from bis[4-(3-aminophenoxy)phenyl] phenylphosphine oxide

Commercially available Kapton polyimide commonly used in various kinds of spacecrafts travelling in Low Earth Orbits (LEO) is severely degraded upon atomic oxygen (AO) exposure. An effective approach is to introduce the AO resistant component i.e., phenylphosphine oxide (PPO) in polymer. A series of copolyimide films has been successfully synthesized from random copolymerization of a PPO based monomer bis[4-(3-aminophenoxy)phenyl] phenylphosphine oxide (mBAPPO), 4,4′-diaminodiphenyl ether (4,4′-ODA) and 3,3′,4,4′-biphenyl tetracarboxylic dianhydride (sBPDA). The glass transition temperature (T g ) and mechanical properties were examined by differential scanning calorimetry and universal mechanical testing machine, respectively. The tensile strength, elongation, and T g of the copolyimide films decreased with the increase of PPO content. The effects of PPO content on the morphology and structure evolvement of copolyimide films were also studied. AO exposure tests were performed using a ground-based AO effects simulation facility. Phosphorus-containing polyimide composite films formed a layer of dense polyphosphate network on the PI film after AO exposure protecting the underlying polymers from further degradation. This layer decreased the mass loss rate and outstandingly improved the AO resistance of PI films. The results of all the studies indicate that these phosphorus-containing copolyimide films can achieve great potential as polymeric materials for potential space applications in LEO and a space durable replacement for Kapton.

Synthesis and fuel cell characterization of blend membranes from phenyl phosphine oxide containing flourinated novel polymers

Novel fluorinated poly(arylene ether)’s are synthesized from polycondensation of bis (p-hydroxy-tetrafluoro) phenyl) phenyl phosphine oxide (PFPPO–OH) with 4,4′-dichlorodiphenyl sulfone (DCDPS) and 2,2-bis(4-hydroxyphenyl)propane (Bisfenol A) (Copolymer 1a) or 2,2-bis(4-hydroxyphenyl) hexafluoropropane (Bisphenol AF) (Copolymer 1b). The fluorinated copolymers have been blended with sulphonated poly(ether ether ketone)-SPEEK by solvent casting method. The water uptake and proton conductivity of the blend membranes decreases with the increase of copolymer content as expected, but proton conductivity values are still comparable to that of Nafion117® membrane. Addition of hydrophobic copolymer 1b to the SPEEK caused increase in water vapor transmission. Methanol permeability of the membranes is decreased to 8.2 × 10−8 cm2 s−1 and 1.3 × 10−9 cm2 s−1 by addition of Copolymer 1a and 1b, respectively and they are much lower than that of Nafion® 117 (1.21E-06 (cm2 s−1). The blend membranes endure up to 6.5 h before it starts to dissolve. Hydrogen and oxygen permeability of the blend membranes is one-hundredth of the Nafion®. Fluorinated polymer improved chemical, mechanical, and hydrolytic stability and also phenyl phosphine oxide structure in the ionomer increased the thermal stability, gas and methanol permeability and overcomed the drawbacks of the Nafion® type membranes.

ChemInform Abstract: Consecutive Dynamic Resolutions of Phosphine Oxides.

A crystallization-induced asymmetric transformation (CIAT) involving a radical-mediated racemization provides access to enantiopure secondary phosphine oxides. A consecutive CIAT is used to prepare enantio- and diastereo-pure tert-butyl(hydroxyalkyl)phenylphosphine oxides.

Synthesis of a novel curing agent containing organophosphorus and its application in flame‐retarded epoxy resins

ABSTRACTA novel amine‐terminated and organophosphorus‐containing compound m‐aminophenylene phenyl phosphine oxide oligomer (APPPOO) was synthesized and used as curing and flame‐retarding agent for epoxy resins. Its chemical structure was characterized by Fourier transform infrared (FTIR) spectroscopy, 1H nuclear magnetic resonance (1H NMR), 13C nuclear magnetic resonance, and 31P nuclear magnetic resonance. The flame‐retardant properties, combusting performances, and thermal degradation behaviors of the cured epoxy resins were investigated by limiting oxygen index (LOI), vertical burning test (UL‐94), cone calorimeter test, and thermogravimetric analysis. The EPO/APPPOO thermosets passed V‐1 rating with the thickness of 3.0 mm and the LOI value reached 34.8%. The thermosets could pass V‐2 rating when the thickness of the samples was 1.6 mm. The cone calorimeter test demonstrated that the parameters of EPO/APPPOO thermosets including heat release rate and total heat release significantly decreased compared with EPO/PDA thermosets. Scanning electron microscopy revealed that the incorporation of APPPOO into epoxy resins obviously accelerated the formation of the compact and stronger char layer to improve flame‐retardant properties of the cured epoxy resins during combustion. The mechanical properties and water resistance of the cured epoxy resins were also measured. After the water‐resistance test, EPO/APPPOO thermosets still remained excellent flame retardant and the water uptake was only 0.4%. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 41159.

Preparation， Mechanical Properties and Flame Retardancy of Phosphorus-containing Polyimide Fibers

The phosphorus-containing diamine compound,bis( 3-aminophenyl) phenyl phosphine oxide( DAPPO),was synthesized with cheap triphenylphosphine oxide and nitro-sulfuric acid. The phosphoruscontaining polyimide( PI) fibers were prepared by introducing DAPPO into the polymer backbone of 4,4'-oxydianiline( ODA),pyromellitic dianhydride( PMDA) and 3,3',4,4'-biphenyl tertracarboxylic dianhydride( BPDA). The results of thermogravimetric analysis indicate that thermal stability of the PI fibers is obviously enhanced with increasing phosphorus content. When n( DAPPO) ∶ n( ODA) is 7 ∶ 93,the value of limiting oxygen index of the fiber has reached 43. These powerfully demonstrate that the flame retardant of PI fibers has been significantly enhanced.

Synthesis of a phosphorus and sulfur‐containing aromatic diamine curing agent and its application in flame retarded epoxy resins

SummaryA novel curing agent of epoxy resins (EPO), bis(3‐amino‐2‐thienyl) phenylphosphine oxide (ABTPPO), was synthesized and characterized by Fourier transform infrared spectroscopy, 1H nuclear magnetic resonance (NMR), 13C NMR, and 31P NMR. ABTPPO was used as a flame retardant curing agent, and a novel halogen‐free flame retardant EPO composite was prepared. The flame retardant properties of ABTPPO‐cured EPO were evaluated in terms of limiting oxygen index and vertical burning test (UL‐94), while the combustion and thermal degradation behaviors were investigated by cone calorimeter test (CONE) and thermogravimetric analysis, respectively. The cured EPO composite passed the UL‐94 V‐1 and V‐2 rating when the sample thickness is 3.0 and 1.6 mm, respectively, and the limiting oxygen index value reached 38.3%. The morphological structures of char residue tested by scanning electron microscopy demonstrated that ABTPPO benefited to the formation of a more compact and homogeneous char layer on the materials' surface during burning, which protected the underlying matrix from decomposition and enhanced the flame retardancy of materials. The cured EPO showed excellent fire performance after the water resistance test because of the low water uptake (0.6 wt%), which demonstrated that the flame retardant EPO composite possessed excellent water resistance property. Copyright © 2014 John Wiley & Sons, Ltd.

Bis(1-phenyl-1H-benzo[d]imidazole)phenylphosphine oxide interlayer for effective hole blocking in efficient phosphorescent organic light emitting diodes based on widely used charge transporting layers

We have developed the efficient phosphorescent organic light emitting diodes (PHOLEDs) based on green-emitting fac-tris(2-phenylpyridine)iridium [Ir(ppy)3] dopant with widely used charge transporting layers. PHOLEDs show the electroluminescence emission from the dopant emitter at 512nm with CIE color coordinates of (0.30, 0.59). We investigated the roll of a 10-nm-thick electron-transporting type bis(1-phenyl-1H-benzo[d]imidazole)-phenylphosphine oxide (BIPO) interlayer in the device efficiencies. BIPO with the deep HOMO energy level and higher electron transporting ability effectively blocks the holes from EML to ETL and improves the charge balance in the EML of the device, resulting in the higher device external quantum efficiency of 14.42%, current efficiency of 44.37cd/A, and power efficiency of 14.67lm/W with a maximum luminance of 75,080cd/m2. The results show that the BIPO interlayer can be very much useful for the efficient low-cost device fabrication.

Validating continuous digital light processing (cDLP) additive manufacturing accuracy and tissue engineering utility of a dye-initiator package

This study tested the accuracy of tissue engineering scaffold rendering via the continuous digital light processing (cDLP) light-based additive manufacturing technology. High accuracy (i.e., <50 µm) allows the designed performance of features relevant to three scale spaces: cell-scaffold, scaffold-tissue, and tissue-organ interactions. The biodegradable polymer poly (propylene fumarate) was used to render highly accurate scaffolds through the use of a dye-initiator package, TiO2 and bis (2,4,6-trimethylbenzoyl)phenylphosphine oxide. This dye-initiator package facilitates high accuracy in the Z dimension. Linear, round, and right-angle features were measured to gauge accuracy. Most features showed accuracies between 5.4–15% of the design. However, one feature, an 800 µm diameter circular pore, exhibited a 35.7% average reduction of patency. Light scattered in the x, y directions by the dye may have reduced this feature's accuracy. Our new fine-grained understanding of accuracy could be used to make further improvements by including corrections in the scaffold design software. Successful cell attachment occurred with both canine and human mesenchymal stem cells (MSCs). Highly accurate cDLP scaffold rendering is critical to the design of scaffolds that both guide bone regeneration and that fully resorb. Scaffold resorption must occur for regenerated bone to be remodeled and, thereby, achieve optimal strength.

Bio-based semi-aromatic polyamide/functional clay nanocomposites: preparation and properties

In this paper we first describe the design and synthesis of two novel cationic functional modifiers, i.e. a functionalized β-cyclodextrin (β-CD) derivative and tris(3-aminophenyl)phenyl phosphine oxide (TAP). Cloisite Na+ (clay-Na) and the modifiers were used for the preparation of the organoclay containing phosphine oxide (clay-PO) and of the organoclay containing β-cyclodextrin (clay-CD) via ion-exchange reaction. Biobased semi-aromatic polyamide (BPA)/functional clay (clay-PO and clay-CD) nanocomposites subsequently were prepared via solution blending. Effects of the two different types of organoclays on the flammable, thermal and mechanical properties of these biobased semi-aromatic polyamide nanocomposites were then studied. The properties of the nanocomposites were found to be strongly related to the nature of the modifiers. The clay-CD based nanocomposites (BPACD) showed more enhancements in thermal stability. The modifier containing the phosphine oxide moiety and triamine groups had stronger interactions with the polymer matrix, and exhibited superior mechanical properties, good flame retardancy and high thermal stability. Thus, we provide a new approach for comprehensive improvement of the properties of these bio-based semi-aromatic polyamide nanocomposite materials.

Innovative self-etching dental adhesives formulated using reactive nanogel additives

Purpose: Enzymatic degradation of poorly resin-infiltrated collagen and hydrolysis of the resin-based polymeric matrix are interfacial degradation mechanisms. However, since the depth of demineralization and resin infiltration in self-etching adhesives (SEAs) occurs simultaneously, the hydrolysis of the hydrophilicmonomers requires further investigation. The aim of this study was to evaluate the microtensile bond strength (mTBS) and the confocal interfacial ultra-morphology of innovative nanogel-modified two-step SEAs bonded to dentin. Methods and materials: Nanogel copolymers were synthesized using isobornyl-methacrylate, urethane-dimethacrylate (UDMA, Esstech, USA)in presence of 2-Mercaptoethanol as a chain-transfer agent and photo-polymerized (2h) in toluene solution with bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide (320-500nm, 2500 mW/cm(2)). A two-step self-etching adhesive was prepared using UDMA, 2-hydroxyethyl methacrylate and 10-methacryloxydecyldihydrogen-phosphate (40/25/15wt%). Camphorquinone and N,N-ethyl-dimethylaminobenzoate were added (0.3 and 0.7 wt%, respectively). Ethanol (14wt%) and water (5wt%) were also included to solvate the resin blend to create a control primer, while non-solvated resin was used as the adhesive. The nanogels were added to create an experimental primer (15wt%) and adhesive (25wt%). Clearfil SE-Bond (CSE; Kuraray, Japan) was also used as control SEA. Several bonding primer/adhesive combinations were applied on middle dentin (5 specimens each group), light cured (20s) and resin composite (N’Durance, Septodont, USA) build-ups (5mm) were created and light-cured (40s each 1-mm layer). The resin-bonded specimens beams (0.9mm(2)) were submitted to mTBS after 24h or 6 months of water aging. The results were statistically analysed by two-way ANOVA and Student–Newman–Keuls test used (p 0.05) after 24h. However, only the control nanogel-free primer/adhesive and the primer/adhesive both containing nanogels showed significant mTBS reduction (p<0.05) after 6 months. The greatest resistance to water aging was attained when the nanogels where present only in the adhesive. The CLSM analysis showed nanogels infiltration within the hybrid layer and low micropermeability both after 24h and 3 months of water aging. Conclusion: The use of nanogels within the composition of two-step SEAs improved their long-termdurability due to infiltration within the hybrid layer, so making the resin-dentine interface hydrophobic andmore resistant to hydrolytic degradation.

Solution-processed bipolar small molecular host materials for single-layer blue phosphorescent organic light-emitting diodes

Three new solution processable small molecular host materials based on the bis-[3,5-di(9H-carbazol-9-yl)phenyl] structural moiety have been developed for blue phosphorescent (FIrpic dopant) organic light-emitting diodes. All three host materials have been characterized as having high glass transition temperatures (Tgs), 155–175 °C, indicative of good morphological stability of their amorphous thin films prepared from the solution process. Whereas N,N-bis-[3,5-di(9H-carbazol-9-yl)phenyl]methylamine (CzPAMe) has the highest solid state triplet energy gap (ET) of 2.73 eV, tetrakis-[3,3′,5,5′-(9H-carbazol-9-yl)]triphenylphosphine oxide (CzPPO) and N,N-bis-[3,5-di(9H-carbazol-9-yl)phenyl]pyrimidin-2-amine (CzPAPm) are two host materials which are potentially bipolar for charge transport due to the electron deficient units of phenylphosphine oxide and pyrimidine, respectively. Due to the insufficient ET (2.56 eV) of CzPAPm, CzPPO or CzPAMe devices are significantly better than CzPAPm devices with or without a 1,3-bis[(4-tert-butylphenyl)-1,3,4-oxadiazolyl]phenylene (OXD-7) co-host. Particularly, having no OXD-7 co-host and no vacuum thermal-deposited extra electron transporting layer, single-layer devices of CzPPO surpass CzPAMe devices and reach current efficiencies as high as 9.32 cd A−1 (or power efficiency of 4.97 lm W−1), one of the highest efficiencies among small molecular devices with the same fabrication process and same device configuration.

Consecutive dynamic resolutions of phosphine oxides

A crystallization-induced asymmetric transformation (CIAT) involving a radical-mediated racemization provides access to enantiopure secondary phosphine oxides. A consecutive CIAT is used to prepare enantio- and diastereo-pure tert-butyl(hydroxyalkyl)phenylphosphine oxides.

An Approach to Benzophosphole Oxides through Silver‐ or Manganese‐Mediated Dehydrogenative Annulation Involving CC and CP Bond Formation

Benzophosphole construction was achieved through the Ag(I) -mediated dehydrogenative annulation of phenylphosphine oxides with internal alkynes in a process involving CC and CP bond formation. A wide range of asymmetrical phenylacetylenes could be employed and the reactions proceeded with perfect regioselectivity. Moreover, the annulation could be conducted even at room temperature when a Mn(III) promoter was used in place of Ag(I) .

New thermally stable nanocomposites reinforced silicate nanoparticles containing phosphine oxide moiety based on poly(amide-imide): synthesis, characterization and flame retardancy study

New type of nanocomposite materials were produced using a poly(amide-imide) (PAI) matrix and novel organoclay as a reinforcing agent by solution intercalation technique in N-methyl-2-pyrrolidone (NMP). The organoclay was prepared from Cloisite Na+ and protonated form of bis(3-amino phenyl)phenyl phosphine oxide via ion-exchange reaction. It was confirmed by Fourier transform infrared spectroscopy and X-ray powder diffraction techniques. A new PAI containing phenylacetic acid moiety was synthesized by direct polycondensation reaction of 2,2′-(5,5′-oxybis(1,3-dioxoisoindoline-5,2-diyl))bis(2-phenylacetic acid) as a new diacid and 4,4′-diaminodiphenylsulfone. Poly(amide-imide)/nanocomposites (PAIN)s containing 4 and 8 % of new organoclay were prepared via solution intercalation method through blending of organoclay with the PAI solution. The nanostructures and properties of the PAINs were investigated using different techniques. Transmission electron microscopy and XRD results revealed the good dispersion nano silicate layers in the polymer matrix. Thermal properties and flame retardancy of the resulting PAINs were investigated by thermal gravimetry analyses and microscale combustion calorimetry techniques. Organoclay shows a good effect on improving the flame retardancy of the PAI, reflecting the decrease in heat release rate (HRR) from 250 W/g for PAI to 185 and 157 W/g for PAINs, while the thermal stability of the PAI nanocomposites only increased slightly compared to the neat polymer.

Synthesis of VS-105: A novel and potent vitamin D receptor agonist with reduced hypercalcemic effects

We have synthesized a novel vitamin D receptor agonist VS-105 ((1R,3R)-5-((E)-2-((3αS,7αS)-1-((R)-1-((S)-3-hydroxy-2,3-dimethylbutoxy)ethyl)-7α-methyldihydro-1H-inden-4(2H,5H,6H,7H,7αH)-ylidene)ethylidene)-2-methylenecyclohexane-1,3-diol). Preparation of a-ring phenylphosphine oxide 11, followed by Wittig–Horner coupling of 11 with the protected 25-hydroxy Grundmann’s ketone 22 generated the precursor 12. Deprotection of the TBDMS groups of 12 produced the target compound VS-105. The biological profiles of VS-105 were evaluated using in vitro assays (VDR receptor binding, VDR reporter gene and HL-60 differentiation) in comparison to calcitriol (the endogenous hormone) or paricalcitol. Furthermore, the PTH suppressing potency and hypercalcemic side effects of VS-105 were evaluated in the 5/6 nephrectomized uremic rats in comparison to paricalcitol. Combining various changes at 20-epi, 22-oxa, 24-methyl, and 2-methylene yielded VS-105 that not only is highly potent in inducing functional responses in vitro, but also effectively suppresses PTH in a dose range that does not affect serum calcium in the 5/6 nephrectomized uremic rats.

Soluble polyarylates containing phosphorus in main chains with thermal stability

ABSTRACTA series of polyarylates containing phosphorus (pho‐PARs) were synthesized from bisphenol A with different molar ratios of bis‐(4‐carboxyphenyl) phenyl phosphine oxide (BCPPO) to terephthalic acid (TPA). When the contents of BCPPO are in the range of 0.4–1.0, the pho‐PARs are readily soluble in a wide range of organic solvents and have the glass transition temperatures of 243.0–260.4°C. The initial degradation temperatures of these pho‐PARs are all above 450°C and their char yields at 800°C under nitrogen atmosphere are in the range of 28.7–33.0%, suggesting they have excellent thermal stability. The results of TG‐FTIR and FT‐IR show the introduction of BCPPO change the decomposition model of the pho‐PARs. The limiting oxygen indexes are at a range of 30.7–34.5%, which suggests that the pho‐PARs are a kind of excellent inherent flame retardant materials. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 3521–3529, 2013