- Telechelic polyphosphazenes: Reaction of living poly(dichlorophosphazene) chains with alkoxy and aryloxy phosphoranimines
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A modification of the method for synthesis of well-defined mono- and ditelechelic polyphosphazenes via the living, cationic polymerization of phosphoranimines has been developed. This process provides access to phosphazene block, comb, and graft copolymer
- Allcock, Harry R.,Powell, Eric S.,Maher, Andrew E.,Prange, Robbyn L.,De Denus, Christine R.
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- Controlled synthesis of polyphosphazenes with chain-capping agents
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N-alkyl phosphoranimines were synthesized via the Staudinger reaction of four different alkyl azides with tris(2,2,2-trifluoroethyl) phosphite. N-adamantyl, N-benzyl, N-t-butyl, and N-trityl phosphoranimines were thoroughly characterized and evaluated as
- Matyjaszewski, Krzysztof,Montague, Robert A.
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- NOVEL ENERGETIC POLYPHOSPHAZENES
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This invention describes the synthesis and use of novel energetic poly(phosphazene) materials suitable for binding high explosives. These materials may also be used as explosives in their own right. The materials possess high energy density and are highly amenable to chemical modification thereby allowing for modification to the physical properties of the material. In particular the tacky and rubbery nature of these materials makes them ideal for use as binder and co-binder materials.
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Page/Page column 6
(2012/03/12)
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- Synthesis of poly(alkyl/arylphosphazenes) via the ambient temperature phosphite-mediated chain-growth polycondensation of (N-Silyl) bromophosphoranimines
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The room temperature addition of stoichiometric amounts of trimethyl phosphite, P(OMe)3, to N-silyl(halogeno)organophosphoranimines BrRR'PdNSiMe3 in chlorinated solvents led to the direct formation of high molecular weight polyphosph
- Taylor, Thomas J.,Soto, Alejandro Presa,Huynh, Keith,Lough, Alan J.,Swain, Anthony C.,Norman, Nicholas C.,Russell, Christopher A.,Manners, Ian
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scheme or table
p. 7446 - 7452
(2011/11/01)
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- Synthesis and reactivity of phosphine-stabilized phosphoranimine cations, [R3P·PR′2=NSiMe3]+
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A series of phosphine-stabilized phosphoranimine cations [R 3 P·PR′ 2 =NSiMe 3 ] + , which canbe regarded as derivatives of the proposed transient reactive intermedi ate [PR′ 2 =NSiMe 3 ] + in the thermalcondensation polymerization of phosphoranimines (R″O) PR′2 =NSiMe 3 to form poly(alkyl/arylphosphazenes) [PR′ 2 =N] n at 180-200°C, have been prepared. The bromide salts [R 3 P·PR′ 2 =NSiMe 3 ]Br [R′ = Me ([6] + ), OCH 2 CF 3 ([8] + ); R 3 P = Me 3 P (a), Et 3 P (b), n Bu 3 P (c), dmpm (d, dmpm = dimethylphosphinomethane), dmpe (e, dmpe = dimethylphosphinoethane)] were prepared from the direct reactions between BrMe 2 P=NSiMe 3 (5) and Br(CF 3 CH 2 O) 2 P=NSiMe 3 (7)and the corresponding tertiary phosphines R 3 P or the diphosp hines Me 2 P(CH 2 ) n PMe 2 (n = 1, 2). Cations of the type [6] + and [8] + , with electron-donating and -withdrawing groups at the phosphoranimine phosphorus center, respectively, undergo facile phosphine ligand substitution with the strong N-donor 4-dimethylaminopyridine (DMAP) to yield the corresponding DMAP-stabilized salts [DMAP·PR 2 =NSiMe 3 ]Br [R = Me ([9] + ), OCH 2 CF 3 ([10] + )]. Cations [6] + with Br - anions are particularly labile: for example, [6a]Br slowly releases PMe 3 , BrSiMe 3 , and forms cyclic phosphazenes such as [Me 2 P=N] 4 . Anion exchange reactions between the salts [6b]Br or [8c]Br and AgOTf (OTf = CF 3 SO 3 ) quantitatively afforded the corresponding and more stable triflate salts [6b]OTf and [8c]OTf.Phosphine ligand abstraction reactions with B(C 6 F 5) 3 were observed for the bromide salts [6b]Br and [8c]Br, which regenerated the phosphoranimines 5 and 7, respectively, and formed the adduct R 3 P·B(C 6 F 5 ) 3 . In contrast, the triflate salts [6b]OTf and [8c]OTf were unreactive under the same conditions. X-ray structural analysis of the P-donor stabilized cations revealed longer P-P and P-N bond lengths and smaller P-N-Si bond angles for cations [6] + compared to analogs [8] + . These structural differences were rationalized using the negative hyperconjugation bonding model. In addition, the ...
- Huynh, Keith,Lough, Alan J.,Forgeron, Michelle A. M.,Bendle, Martin,Soto, Alejandro Presa,et al.
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experimental part
p. 7905 - 7916
(2009/10/16)
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- New amphiphilic poly[bis(2,2,2-trifluoroethoxy)phosphazene]/ poly(propylene glycol) triblock copolymers: Synthesis and micellar characteristics
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Amphiphilic triblock copolymers were synthesized with two hydrophobic poly[bis(2,2,2-trifluoroethoxy)phosphazene] blocks linked to a central poly(propylene glycol) block. These were synthesized via the cationic polymerization of chlorophosphoranimines and
- Allcock, Harry R.,Song, Yun Cho,Steely, Lee B.
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p. 8334 - 8338
(2007/10/03)
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- (ALKYLIDENEAMINO)PHOSPHORANES
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phosphoranes react with polyfluorinated aliphatic alcohols in presence of triethylamine with the formation of phosphoranes or (alkylideneamino)tetrakis(polyfluoroalkoxy)phosphoranes.The latter course is re
- Shermolovich, Yu. G.,Abramov, V. Yu.,Markovskii, L. N.
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p. 1588 - 1594
(2007/10/02)
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- Synthesis and Structure of Carborane-Substituted Cyclic and Polymeric Phosphazenes
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The synthesis of the first carborane-substituted cyclophosphazenes together with the preparation, by two different approaches, of the first carborane-substituted phosphazene linear polymers is reported.The cyclic derivatives IV are both precursors and model compounds for the analogous polymeric derivatives VI.The crystal and molecular structure of IV (R = phenyl) has been investigated by single-crystal X-ray diffraction techniques.The molecule contains a planar phosphazene trimer ring bound directly to the phenyl carboranyl group through a P-C bond.The absence of steric and electronic influences by the phosphazene and carboranyl units on each other is discussed.The crystal of IV (R = phenyl) are monoclinic with the space group P21/n and with a = 9.476 (3) Angstroem, b = 12.984 (2) Angstroem, c = 18.726 (3) Angstroem and β = 100.11 (3) deg with V = 2268.2 (3) Angstroem3 and Z = 4.The P-N bond distances are all similar and average 1.574 Angstroem.The P-C bond length is 1.820 Angstroem, and the Cl-P-C angle was found to be 102.4 deg.The reaction between high molecular weight poly(dichlorophosphazene), (NPCl2)n, and methyl- or phenyl-1-lithio-o-carborane was also studied.Chlorine substitution is a slow process, and is accompanied by chain cleavage.The nucleophilic replacement of the halogen atoms yielded high polymers of structure IX that contain up to 15percent of the side groups as carboranyl units.The remaining chlorine atoms were replaced by treatment with sodium trifluoroethoxide.The properties and structure of the macromolecules are discussed.
- Allcock, H. R.,Scopelianos, A. G.,O'Brien, J. P.,Bernheim, M. Y.
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p. 350 - 357
(2007/10/02)
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