ESR and NIR-FT-raman study of potential molecular ferromagnetics - poly(diacetylenes) substituted with nitroxyl radicals

Summary form only given. Nitroxyl radicals substituted diacetylenic (DA) monomers, exemplified by the formulas: have been synthesized having in mind the preparation of corresponding poly(diacetylenes) (PDA) by the solid state topochemical polymerization. Such polymers should contain a system of topologically ordered unpaired spins in the vicinity of main p-conjugated chain of PDA. Accordingly, they are useful models for probing ways to, e.g., polymer ferromagnetics or Self doped PDAs. All the monomers were characterised using EA, TGA, DSC, ESR, FTK UVNIS/NIR, FT-Raman, X-ray analysis and magnetometry methods. The monomers turned out to be inactive to UV- or g-initiation, while heating did led to the solid state polymerization. The polymerization kinetics measurements by means of DSC have been paralleled by using optical (UV/VIS/NIR-, FTIR- and NIR-FT-Raman spectroscopy) and magnetic (ESR) methods. The potency and peculiarities of the NIR-FT-Raman (Nd:YAG 1.064 mm excitation) technique during analysis of conjugated polymers are discussed by using the results for both nitroxyl-substituted and classic PDAs.