Poly(ethylene oxide) (PEO) is a polymer of great interest due to its prevalence in biomedical, pharmaceutical, and ion conductive systems. In this study, the crystallization behaviors of a PEO with 22 monomer units (PEO22) and a PEO having the same degree of polymerization but with an additional 1,4-disubstituted 1,2,3-triazole ring in central position of the chain (PEO11-TR-PEO11) are investigated. PEO11-TR-PEO11, shows one type of lamella crystal, after cooling to T = 0 degrees C, but structural changes during heating below their final melting ate detected by WAXS, DSC, POM, and solid-state NMR spectroscopy. The lamella thickness increases, but simultaneously the helix helix distance decreases and an additional Bragg reflection appears at 2 theta = 22.1 degrees. A model is proposed, which explains these structural changes by incorporation of the TR ring into the crystals which are additionally stabilized by attractive C-H center dot center dot center dot pi interactions of:the TR rings. Additionally, two different types of extended chain lamella crystals are found in PEO22 by SAXS which are discussed in the context of fractionation caused by the molar mass distribution obtained from MALDI-ToF data.