A new selective agent for poly(tetrahydrofuran) degradation as a tool for the determination of the crystallite core size

The method formerly used to determine the crystallite core size of polyethylene was applied to poly(tetrahydrofuran) (PTHF). This method is based on the different diffusivity of a chaincleaving agent in crystalline and amorphous parts of the polymer. Butyllithium was used as a cleaving agent of PTHF. The degree of polymerization of the undecomposed part of the polymer (PTHF crystallites) was determined by gel permeation chromatography. This value agrees well with the value to be expected from the size of the crystallites determined small-angle X-ray scattering.