Investigation on the Folding Mode of a Polymer Chain in a Spiral Crystal by Single Molecule Force Spectroscopy  

作　　者：Yu Song Wei Feng 张文科 

机构地区：[1]State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University [2]Institute of Atomic and Molecular Physics, Jilin University

出　　处：《Chinese Journal of Polymer Science》2014年第9期1149-1157,共9页高分子科学（英文版）

基　　金：financially supported by the National Natural Science Foundation of China(Nos.20974039,21221063 and 91127031);the National Basic Research Program(2013CB834503);the Program for New Century Excellent Talents in Universities(NCET-11-0205)

摘　　要：Investigation on the folding mode of a single polymer chain in its crystal is significant to the understanding of the mechanism of the fundamental crystallization as well as the engineering of new polymer crystal-based materials. Herein, we use the combined techniques of atomic force microscopy （AFM） imaging and force spectroscopy to pull a single polyethylene oxide （PEO） chain out of its spiral crystal in amyl acetate. From these data, the folding mode of polymer chains in the spiral crystal has been reconstructed. We find that the stems tilt in the typical flat area, leading to the decrease in the apparent lamellar height. While in the area of screw dislocation, the lamellar height gradually increases in the range of several nanometers. These results indicate that the combined techniques present a novel tool to directly unravel the chain folding mode of spiral crystals at single-molecule level.Investigation on the folding mode of a single polymer chain in its crystal is significant to the understanding of the mechanism of the fundamental crystallization as well as the engineering of new polymer crystal-based materials. Herein, we use the combined techniques of atomic force microscopy （AFM） imaging and force spectroscopy to pull a single polyethylene oxide （PEO） chain out of its spiral crystal in amyl acetate. From these data, the folding mode of polymer chains in the spiral crystal has been reconstructed. We find that the stems tilt in the typical flat area, leading to the decrease in the apparent lamellar height. While in the area of screw dislocation, the lamellar height gradually increases in the range of several nanometers. These results indicate that the combined techniques present a novel tool to directly unravel the chain folding mode of spiral crystals at single-molecule level.

关 键 词：Folding mode Spiral crystal Single molecule force spectroscopy Atomic force microscopy. 

分 类 号：O631.12[理学—高分子化学]