1,721,014 research outputs found
ORGANOMETALLIC AND COORDINATION CHEMISTRY ON PHOSPHAZENES .1. ZN(II), PD(II) AND PT(II) COMPLEXES ON SCHIFF BASE-CONTAINING CYCLOPHOSPHAZENES
No full textFluorinated polyphosphazenes : a survey
No full textA general survey of fluorinated phosphazene polymers starting from their synthesis in 1965 to recent times is presented. Various types of fluorinated phosphazenes are described depending on the way fluorine atoms are connected to the polyphosphazene skeleton. The characterization, properties and practical utilization of these compounds in different domains are critically discussed
Functionalized poly(organophosphazenes)
No full textIn this paper we highlight the general strategies established over the time for the functionalization of poly(organophosphazenes) in order to modify both the chemical structures and the chemicophysical properties of these substances. These modifications have been obtained by reacting poly(dichlorophosphazene) with difunctional nucleophiles thus introducing selected chemical functions into the polyphosphazene substrates or by carrying out suitable functionalization processes on pre-synthesized phosphazene macromolecules. Particular attention has been paid to the chemical modification of polyphosphazenes containing 2,2,2-trifluoroethoxy, phenoxy, 4-ethylphenoxy, 4-sec-butylphonoxy and 4-methoxyphenoxy substituents as these groups were attached to phosphazene homopolymers and copolymers that have been considered in the past for industrial development
Fluorine containing phosphazene polymers
No full textIn this paper we highlighted the synthesis, characterization, and practical exploitation of different types of polyphosphazenes substituted with fluorinated groups. There are several ways in which fluorine atoms can be inserted into polyphosphazenes, all of which leading to different polymers showing a wide range of characteristics. In general it is true that the insertion of fluorine atoms into phosphazene macromolecules leads to an enhancement of the thermal stability, flame resistance, low-temperature elastomericity, and chemical inertness of the phosphazenes obtained. The contribution of Italian research groups to the preparation and exploitation of organic commercial macromolecules grafted onto fluorinated polyphosphazenes is also reviewed
cyclic phosphazene derivatives containing benzene groups on the substituents at the phosphorus
No full textCyclic aryloxy- or arylamino-substituted phosphazine derivatives containing photoinitiator groups substituted at the phosphorus formed from benzene derivatives of different types so as to give rise to radical polymerisation reactions for vinyl monomers under light or induce photo-crosslinking phenomena in both preformed polymers which include particularly reactive centres and unsaturated acrylic resins of various kinds
Aryloxy-substituted cyclo- and poly-phosphazenes containing epoxy functions
No full textThe present invention relates to aryloxy-substituted cyclic and polymeric phosphazenes of general formula: in which X, X', w, y and z have the meaning defined in the text, containing epoxy functions. The preparation of these products is effected by reaction between cyclo- and poly-phosphazenes having free hydroxyl functions with compounds which possess methylenic [alpha]-chloro or [alpha]-bromo groups and simultaneously contain epoxy functions, or by a reaction of epoxidation of cyclo- or poly-phosphazenes containing olefinic double bonds in the side substituent groups with organic peracids of various types
Cyclic and polymeric phosphazenes containing Bengal Red or other colouring agents suitable for use as sensitizers for photooxidation
No full textCyclic and polymeric phosphazenes suitable for the photosensitized production of singlet oxygen having the general formula: in which X, X', (w + y + z) have the meanings defined in the text, containing Bengal Red or other colouring agents of the 9-phenyl-xanthene series which are bound to the cyclic or polyphosphazene matrix by reaction between the carboxylate group present in the dye and an [alpha]- bromomethylene group introduced into the phosphazene substrate
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