Organizing Nanoparticles in Semicrystalline Polymers by Modifying Particle Diffusivity.

We have previously shown that semicrystalline polymers can be reinforced by adding nanoparticles (NPs) and then ordering them into specific motifs using the crystallization process. A key result we have found is that when the spherulite growth rate is slowed below a critical value, then, NPs can order into the amorphous interlamellar regions of the semicrystalline structure. The effects of spherulite growth rate in this context have previously been examined, and here we focus on the role of NP diffusivity.

Atomic Force Microscopy Tracking of Nanoparticle Migration in Semicrystalline Polymers.

We present tracking of silica nanoparticle (NP) migration from a poly(ethylene oxide) (PEO) melt into interlamellar region using 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 imaging on the large (50 nm) NPs helps track the migration into the amorphous zones.