抄録
1, 2-di (o-methylphenoxy) ethane-p, p′-dicarboxylic acid (A) was derived from o-cresol by our own procedure. The polyether-ester (I) having the following chemical formula was then prepared by the polycondensation of the dimethyl-ester of (A) with ethylene glycol.
The effects of the CH3-group in the benzene ring on the fiber-forming propertes of (I) were studied in comparisen with those of the H-atom of polyethylene 1, 2-diphenoxyethane-p, p′-dicarboxylate (II), as well as those of the CH3O-group of polyethylene 1, 2-di (o-methoxyphenoxy) ethane-p, p′-dicarboxylate (III) reported in the previous paper.
The crystallization rate was measured and it was found that the ease of crystallization is in the
order of H->CH3-_??_CH3O- with respect to the side groups. By differential thermal analysis, it was shown that the glass transition temperature, the melting point and the cold crystallization temperature are in the following order: H-=CH3-<CH3O-, H-=CH3->CH3O-and H-<CH3-, respctively. The fiber periods of (I), (II) and (III) calculated from X-ray fiber diagrams were slightly less than the length of a repeating unit required for fully extended planar zig-zag chains. In addition, the mechanical properties of the drawn and annealed fibers were investigated, and it was shown that the Young's modulus of (I) is as high as that of (II).
In conclusion, it may be said that the effect of the methyl side group in the ortho-position for the ethylene ether linkage is not very large and therefore (I) has the good fiber-forming properties similar to those of (II).
