Detection of the Difference in Local Chain Conformation Between Cyclic and Linear Oligomers in Solution: An X‐Ray Scattering Study on Oligo(dimethylsiloxane)s in Bromocyclohexane

ABSTRACT The particle scattering functions as functions of the magnitude of the scattering vector for cyclic and linear oligo(dimethylsiloxane)s were measured in bromocyclohexane at 29.5. A significant difference was observed in between the cyclic and linear samples, both with the degree of polymerization equal to 5, in the range of 0.4 , while for the cyclic and linear samples of almost coincide with each other in the range of 0.4 . The behavior of for the cyclic sample of is almost the same as that for the cyclic sample of for 0.4 . These results indicate that the difference in the local chain conformation between cyclic and linear chains is detectable by examining the behavior of even in the case of oligomers. However, the analysis of using either a coarse‐grained model or full‐atom molecular structures in vacuum, both having been commonly employed in literatures, was not effective for the present experimental data. This result suggests that solute–solvent interference must be considered for analysis of of such small cyclic chains.