Crystal structure of optically active poly(isopropylethylene oxide)

The crystal structure of optically active poly(isopropylethylene oxide) was analyzed by x-ray diffraction. Two molecular chains having twofold screw symmetry pass through an orthorhombic unit cell with parameters a = 12.85 Å, b = 7.52 Å, and c (fiber period) = 5.55 Å and space group P2₁2₁2₁-D. The crystal structure was refined by the constrained least-squares method. The molecular structure consists mainly of ?TG sequences and is very similar to the (9/4) helical structure in poly(tert-butylethylene oxide).