In Situ Atomic Force Microscopy Tracking of Nanoparticle Migration in Semicrystalline Polymers

Abstract

We present in situ tracking of silica nanoparticle (NP) migration from a poly­(ethylene oxide) (PEO) melt into interlamellar region using in situ atomic force microscopy (AFM). Our results confirm the previous hypothesis that NPs migrate into the interlamellar regions at crystallization growth rates smaller than a critical value under isothermal conditions. Under these slow crystallization conditions, bare silica NPs are rejected as defects by the growing crystal of PEO, and the in situ imaging on the large (50 nm) NPs helps track the migration into the amorphous zones. We extend this AFM technique to estimate lamellar growth rates that correlate with spherulite growth rates determined by polarized light optical microscopy (PLOM) but at smaller undercoolings than are typical for PLOM.

Crystallization and molecular mobility in renewable semicrystalline copolymers based on polycaprolactone and polyisosorbide

“…This is due to the isothermal stay for some minutes at T where the polymer chains have become mobile (rubbery state) and most probably annealing of crystallization or additional cold crystallization take place. 48 Thus, crystal rearrangements 97,98 and/or additional growth is expected. This occurs in all cases of PCL-based samples.…”

Revolutionizing the structural design and determination of covalent–organic frameworks: principles, methods, and techniques

“…The development of diverse in situ SPM technologies allows researchers to characterize individual molecules on the substrate and in gas and liquid environments. When operated in a liquid environment, SPM techniques have been widely applied in studying dynamic processes or events in liquids, such as migration, 280 aggregation 316 and crystal growth. 317 For instance, S. Schadler et al utilized in situ AFM to track the migration of silica nanoparticles (NPs) from a poly(ethylene oxide) (PEO) melt into the interlamellar region.…”

“…12m). 280 As another example, the tip of STM can desorb individual hydrogen atoms from a hydrogen-saturated silicon surface and induce synthesis steps of a biphenyl molecule in a liquid environment, indicating the capability of SPM in repairing or manipulating COF structures and studying their interactions with molecules in liquids. 318 For measurements in a gas environment, Suzuki et al devised an apparatus including STM and AFM to investigate highly oriented pyrolytic graphite (HOPG), revealing that STM captured atomic-resolution images across hydrogen, helium, neon, and argon atmospheres.…”

“…Reproduced with permission. 280 Copyright 2022, American Chemical Society. (n) Monitoring reversible trans-cis isomerization and electric field-induced manipulation of azobenzene derivatives on the Au (111) surface using in situ STM.…”

“…(m) Dynamics of NP migration and its impact on crystallization mechanisms monitored by in situ AFM. Reproduced with permission 280. Copyright 2022, American Chemical Society.…”