摘要
Tapping mode atomic force microscope has been applied to observe single-chain PMMA particles which were stored for six months at room temperature after sprayed hom very dilute solutions in good solvents, good/poor mixed solvents, and a theta solvent. Monodisperse PMMA standards of molecular weights ranging from 7.90 x 10(4) to 1.3 x 10(6) were used to investigate the effect of molecular weight on the size of the single-chain PMMA particles. These single-chain particles showed close to spherical shapes. The morphology of single-chain PMMA particles of a given molecular weight was found to be identical in spite of different solvents used for solution spraying. Molecular weight dependence of the particle dimension was also found. The diameters of single-chain PMMA particles after correction of tip-geometry effect were compared to the values estimated from molecular weight and density.
Tapping mode atomic force microscope has been applied to observe single-chain PMMA particles which were stored for six months at room temperature after sprayed hom very dilute solutions in good solvents, good/poor mixed solvents, and a theta solvent. Monodisperse PMMA standards of molecular weights ranging from 7.90 x 10(4) to 1.3 x 10(6) were used to investigate the effect of molecular weight on the size of the single-chain PMMA particles. These single-chain particles showed close to spherical shapes. The morphology of single-chain PMMA particles of a given molecular weight was found to be identical in spite of different solvents used for solution spraying. Molecular weight dependence of the particle dimension was also found. The diameters of single-chain PMMA particles after correction of tip-geometry effect were compared to the values estimated from molecular weight and density.
基金
This work was supported by The National Key Project for Fundamental Research"Macromolecular Condensed State".
