Chain Tilt and Crystallization of Ethylene Oxide Oligomers with Midchain Defects.

Many text books and publications do not focus on the necessity of chain tilting in crystalline lamellae of oligomers and polymers, a fundamental aspect of their crystallization already discussed by Flory. Herein we investigate the chain tilt of ethylene oxide oligomers (EOs) containing various midchain defects by WAXS, SAXS and solid state C MAS NMR spectroscopy. At low temperatures, one out of the two EO chains of EO--EO and EO-TR-EO containing a 1,3-disubstituted benzene or a 1,4-disubstituted 1,2,3-triazole defect in central position of the oligomer chain forms crystals and the other EO chain as well as the defect remain in the amorphous phase.