PTeOX lamellar crystals

The SAXS patterns of the melt-crystallized PTeOX shows only a ring-like diffuse scattering to indicate no preferential orientation of the lamellar crystal formed from the molten phase. 

Therefore, it is suspected that the fine structure of the as-polymerized PTeOX is different from the melt-crystallized (the lamellar crystal), since the rearrangemoit of the polymer chains of the as-polymerized by annealing takes place even above the starting temperature (TJ of the melting. 

Figure 4.22 shows the 009 reflection profiles of PTeOX as-polymerized at 105 °C and aimealed. Armealing of the sample leads to the same behavior as in the case of PTOX. A slight shifted peak also was observed in the PT OX atmealed even at 135 °C for 40 min. The 009 and 0018 reflections of PT X were obtained at 80 °C (this polymer having no lamellar crystal as mentioned above) and annealed at 160 °C for 30 min. 

Recent studies in the fine structures of radiation polymerized PTOX show that they are disordered crystals in which maln-crystal-lites and sub-crystallites are arranged in series (7)- The fine structures of PTEOX are even more disordered and complex than those of PTOX, and are believed to possess an oriented lamellar morphology. However, when the post-polymerization is carried out at temperatures above 90 C, the sub-crystallites disappear. WAXS studies indicate that the (009) and (0018) reflections of PTEOX have an asymmetrical profile, suggesting the existence of two different lattice spacings along the fiber axis. Odajima, et al. (8) suggested that there may be two kinds of crystallites present, namely those with the extended fibrillar and the folded lamellar morphologies. 

In their recent publication, Odajima and his coworkers (11) have shown that the rather broad and asymmetric (009) and (0018) WAXS profiles of PTEOX polymerized above 80 C by radiation initiation may be resolved into two curves. One can be attributed to the extended chain crystals (the only kind present in sample PTEOX-12), and the other is the lamellar type crystals with thicknesses of about 100 X. Figure 7 shows that the line shape of the (009) profile of the plasma sample PTEOX-5P is rather sharp and similar to that of the radiation sample PTEOX-25. The half width (A20)1 = 1.72° or 0.012 X ) of the (0018) profile is narrower than those of PTEOX-25 (2.50° or 0.017 A ) and PTEOX-80 (2.25° or... 

In conclusion of the melting behavior of PTeOX, the endothamic profiles of PTeOX prepared below 90 °C is different from that prepared above 90 °C. From the results of the X-ray diffraction, mentioned in Section 2, can be seen that the polymerization of T OX in the solid state produces the main and sub-crystals below 90 °C, while the main crystal and a aystal corresponding to 100 A scattering in SAXS are formed above 90 °C. Chatani et al. used PT OX prepared at 62 C to show main and sub-crystals from WAXS study, and Amano et al. used PTeOX prepared at 100 °C to w only lamellar type crystals from SAXS and EM studies. Both results seem to be somewhat similar, but we can not compare their data since the characteristics of PTeOX prepared at different temperatures are different. PTeOX prepared at 100 °C contains the main crystals beside lamellar type crystals as mentioned later. 

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