The Relation Between an Irregular Molecular Structure of a High-Polymeric Substance and its Upper Limit of the Degree of Crystallinity

Kazuo Nagai, Eiichi Nagai
1958 Kobunshi Kagaku  
Mathematical evaluation was made about the effect of an irregular molecular structure of a high-polymeric substance on the decrease of its degree of crystallinity. The assumptions in volved are as follows. A high polymer having irregularity not at all in its chain skeleton may crystallize perfectly up to 100%. In order that a polymer can anyhow crystallize to some extent, it would be necessary for the molecular chain to be intervened by sequences composed of crystallizable chain elements, where
more » ... not the whole i but (i-i0) members of these elements could participate in the crystallite formation. io is the number of the elements made incompetent by the interruption of the sequences of not crystallizable other elements adjoining to them. The derived expression is : (Upper limit of the degree of crystallinity)=(Fraction of the crystallizable elements for the total numbers of the elements) x pi°, where p denotes the probability that a crystallizable element is followed by another idenical to it in the course of polymerization. * The Osaka Industrial Research Institute (Daini-Nishi-2 chome Oyodo-ku Osaka)
doi:10.1295/koron1944.15.778 fatcat:gbgqa6yuqzb4ncp7tei2bmrwdm