The crystal structure of poly[oxy-l,3-(2-cyanophenylene)-oxy-l,3-phenyleneJ was determined by X-ray diffraction. The structure belongs to the monoclinic system with the space group P21/a, and has unit cell constants of a=8.62A, b=13.07/~, c (chain axis)=9.03 A and fl=99.0 ° (second setting). There are four monomer units (i.e. four chains) in the unit cell. The molecules in the crystal are constricted by 0.5 A per monomeric unit from the fully extended conformation, and the planes of the adjacent benzene rings lie at an angle of ~ 90 ° to each other. The longitudinal elastic modulus of the crystalline component was estimated to be 44 GPa from the X-ray diffraction measurements. Because the polymer is not fully extended, this elastic modulus is not very high.
Посилання на статтю:
Molecular and crystal structure of a polycyanoarylether: poly[oxy-1,3-(2- cya nophenylene) -oxy- 1,3- phenylene] / Yasushi Ichikawa and Yozo Chatani // Polymer. – 1994. – Vol 35. – P. 18-22.