| Popis: |
Allylnadic anhydride can be easily imidized with aliphatic, acyclic and aromatic primary amines. A new class of heat resistant thermosets, bisallylnadimides, has been developed. The two double bonds (norbornene and allyl) present in the allylnadimides may behave differently towards the type of initiator employed for polymerization. N-Phenylallylnadimide (NPANI) had been polymerized thermally, radically and cationically. The polymers obtained were characterized using infrared spectroscopy (IR), thermogravimetric analysis (TGA) and thermal volatilization analysis (TVA). The remarkable difference observed in the IR spectra of the differently polymerized samples was the absorption peaks in the region 800–1100 cm−1 which were sharp in cationically polymerized sample. TGA showed the radically polymerized sample starts to evolve volatiles at lower temperature (160 °C) than the other two samples (268 and 212 °C for the thermally and cationically polymerized samples, respectively). TVA was carried out in high vacuum and both the volatile and cold ring fractions were analyzed in a GC–MS. The chemical structure of the products suggest the contribution of Diels–Alder, ene and cyclopolymerization reactions during polymerization. The formation of the degradation products had been explained as due to the presence of varying structural entities in the polymer. |
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