Poly organophosphazene s

The volume of publication in the developing area of the poly(organophosphazene)s, is increasing rapidly across a broad area. The potential structures and properties of this class of polymers is extensive, and their commercial usefulness in a wide range of applications is expected to increase markedly. 

Molecular Structure.—Improved Af-ray diffraction data have been reported for highly purified poly(dichlorophosphazene). The results are consistent with a cis-trans planar chain conformation and with a chain-packing arrangement allowing appreciable rotational disorder between adjacent chains. Measurements of crystalline transitions and related physical properties of poly(dichloropho phazene) have also been described.  

A series of poly(aryloxyphosphazene)s has been prepared with phenoxy and p-ethylphenoxy substituents in varying ratios. The thermal, morphological, and rheological properties of this series were studied and the data were found to be consistent with the behaviour expected of a random copolymer composition. The thermal transition behaviour of blends of poly(aryloxyphosphazene) copolymers 

Care must be taken to avoid the formation of insoluble poly(dichlorophospha-zene) inorganic rubbers , and in the selection of the proper conditions for conversion into poly(organophosphazene)s. Although problems still exist in the synthetic area, work has progressed to where a wide variety of poly(organo-phosphazene) polymers are now available.  

Synthesis.—series of poly(arylaminophosphazene) copolymers have been prepared by allowing mixtures of two arylamines to react completely with poly(dichlorophosphazene). The substituent ratios of the copolymers formed, examined by high temperature proton n.m.r. spectroscopy, generally reflect the expected steric and electronic eifects on the relative reactivities of the aiylamines studied. The copolymers were found to have intrinsic viscosities of 0.64— 1.25 dl/g, Tg of 75 to 104 °C and decomposition temperatures of 220— 260 °C. A further series of catalysts for the polymerization of N3P3Q, including aluminium alkyls and alkoxy-derivatives of N3P3Cle, has been proposed. 

A new route to poly(organophosphazene)s has been reported in which the phosphazene cyclic trimer [NP(OCHjCF3)2J3 is copolymerized with (NPa )3 to yield a new series of rubbers. The copolymers have been characterized by means of substitution reactions and P n.m.r. analysis. The synthesis of resins by the 

Busulini, M. Osellame, S. Lora, and G. Pezzin, Macromol. Chem., 1977,178, 111. 

The poly(aminophosphazene)s are film-forming thermoplastics rather than rubbers. Their Tg values tend to be higher than those of related alkoxy- and 

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Originality Energetic poly(organophosphazene)s have not been prepared using the... 

Poly(organophosphazene)s Prepared by Macromolecular Substitution of [NPCbJn... 

Many poly(organophosphazene)s can be modified without chain scission. Thus, it is possible to carry out conventional organic reactions on the side groups (substituents) of the polyphosphazene backbone. This is an important feature that allows elaboration of polyphosphazenes into many new types of polymers. A few examples are given below to illustrate this principle. 

Fig. 3.54 Selected poly(organophosphazene)s in the order of their increasing Tg...

This Report continues to review those developments of significance in the area important in the context of this volume, i.e., polymers essentially linear in nature, and consisting of backbone structures made up of predominantly inorganic elements. The review is limited by size to polymers derived from the most important and active areas of the poly(organosiloxane)s, poly(organophosphazene)s and polythiazyls. 

Some Properties and Applications of Linear Poly(organophosphazene)s 500... 

The synthesis of poly(organophosphazene)s (101) with a variety of substituents was described in many books and review papers, as mentioned already in Section 4.18.6.1. For example, Allcock in his comprehensive reviews discussed various structures of polyphosphazenes and their diversity of properties. 

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