Abstract
Elastic modulus of the crystal lattice parallel to the chain axis (El), for polyethylene oxide (PEO) was determined by an X-ray diffraction method. The modulus was found to be
PEO: Eι=10×104kg/cm2 (21±1°C).
The value is about twice as large as the value calculated by Enomoto et al.((4.6-4.9)×104kg/cm2). However, using the conformational model and the force constants of PEO reported recently by Tadokoro et al., we obtained Eι-value of (7.8-9.2)×104 kg/cm2 which showed good agreement with the observed value.
The observed Eι-value of PEO is the smallest among those so far found for polyethers. The elastic moduli of polyethers expressed by a general formula -[-(CH2) m-O-] n, were discussed in terms of the chain skeleton conformation in the crystalline state.
