α,ω-Di(glycerol carbonate) telechelic polyesters and polyolefins as precursors to polyhydroxyurethanes: an isocyanate-free approach

alpha , omega -Di(glycerol carbonate) telechelic poly(propylene glycol) (PPG), poly(ethylene glycol) (PEG), poly(ester ether) (PEE), and poly(butadiene) (PBD) have been synthesized through chemical modification of the corresponding alpha , omega -dihydroxy telechelic polymers (PPG-OH sub(2), PEG-OH sub(2), PEE-OH sub(2) and PBD-OH sub(2), respectively). Tosylation of the polymer diols with 4-tosylmethyl-1,3-dioxolan-2-one (GC-OTs) afforded, in high yields, the desired PPG, PEG, PEE and PBD end-capped at both termini with a five-membered ring cyclic glycerol carbonate (4-hydroxymethyl-1,3-dioxolan-2-one, GC). The GC-functionalization of the polymers at both chain-ends has been confirmed by NMR ( super(1)H, super(13)C, 1D and 2D) and FTIR spectroscopies. Using PPG-GC sub(2) to demonstrate the concept, the corresponding polyhydroxyurethanes (PHUs/non-isocyanate polyurethanes (NIPUs)) have been subsequently prepared following a non-isocyanate method upon ring-opening catalyst-free polyaddition of the PPG-GC sub(2) with JEFFAMINEs (M sub(n) = 230-2000 g mol super(-1)). The effect of various additives introduced during the polyaddition reaction has been studied at different temperatures. In particular, addition of LiBr (5 mol%) to the reaction medium was found to slightly promote the cyclocarbonate/amine reaction. The polymerization process was supported by FTIR and SEC analyses.