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The reaction of a mixture of [NPCl2]n and Cs2CO3 first with (R)-(+)-1,1′-binaphthyl-2,2′diol (HO-C10H6-C10H6-OH) (binaphthol) and subsequently with phenol (HO-C6H5) in refluxing 1,4dioxane gave the series of the optically active random copolymers {[NP(O2C20H12)]x[NP(OC6H5)2]1-x}n (2). Absolute molecular weight distributions and radius of gyration have been determined by size exclusion chromatography, using simultaneously multiangle light scattering and differential refractive index detectors. The dependence of the dimensions of the polymers on the molecular weight through the corresponding scaling laws is studied. In addition, a stereochemical study of homopolymers [NP(O 2C20H12)]n 1 and copolymers 2 based on the CD exciton chirality method is also included. The reaction of the partially substituted polymer [NP(R-O2C20H12)0.4(Cl2)0.6]n with the stoichiometric amount of racemic binaphthol, or with a large excess of the latter, in the presence of Cs2CO3 gave the same polymer [NP(R-O2C20H12)0.4-(rac-O2C20H12)0.4]n [(-)-3] irrespective of the amount of racemic binaphthol used, showing no enantiomeric induction by the R-binaphthoxy units already present in the polymer.

Polydichlorophosphazene [NPCl 2 ] n reacts with the diphenol 2,2Ј-(HO)C 6 H 4 -C 6 H 4 (OH) in THF in the presence of K 2 CO 3 to give the polymers [NP(O 2 C 12 H 8 ) ⅐ x(OC 4 H 8 )] n (1) that contain variable ammouts of polytetrahydrofuran (PTHF) with x ranging from 0.05 to 0.8. This PTHF content (x) depends on the method followed to prepare the THF solutions of [NPCl 2 ] n used for the reactions with the biphenol and can be made negligibly small, forming these solutions in the presence of K 2 CO 3 . This reveals the presence in the [NPCl 2 ] n of acidic species capable of catalyzing the ring opening polymerization of THF. Polyphosphazene [NP(O 2 C 12 H 8 )] n (2) was prepared completely free of PTHF using dioxane as solvent. A comparison of the thermal behavior and morphological data of the polymers 1, 2, PTHF (5), and mixtures of [NP(O 2 C 12 H 8 )] n ϩ x(OC 4 H 8 ) m (4) revealed that the products 1 are strongly interacting polymer blends and ruled out the possibility of block copolymers.

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SYNOPSISA very convenient synthetic method is described for the known cyclic aryloxyphosphazenes [N3P3(OC6H4-R)6] (R = Br, CN, CHO, COCH3, COC6H5, and NO,). The method is based on the direct reaction of [N3P3C16] with six equivalents of the para-substituted phenols HOC6H4-R and K&03 in refluxing acetone and is characterized by very short reaction times and very simple workups, leading directly to the analytically and spectroscopically pure products in very high yields. In the cases where R = H, But, or OCH3, the reactions were much slower, but the time could be shortened by using [Bu4N]Br as the phase-transfer catalyst. Similarly, the polymers [NP(OC6H4-R),], can be conveniently obtained in ca. 70% and good analytical purity from polydichlorophosphazene [NPCl,], and the parasubstituted phenols HOC6H4-R (R = Br, CN, COCH3, COC6H5, and NO2) in the presence of K2C03 using THF as the solvent.