Manipulating Semicrystalline Polymers in Confinement

TL;DR

This paper introduces processing strategies to manipulate the microstructure of nanoscale confined polymers, enabling control over crystallization and orientation to tailor properties like ferroelectricity.

Contribution

It presents novel methods adapted from bulk processing to control solidification and microstructure of confined polymer nanostructures, including nucleating agents and temperature tuning.

Findings

Nucleating agents modify crystallization kinetics of confined PVDF.

Crystallization temperature influences crystal orientation.

High temperatures induce ferroelectric nanostructures.

Abstract

Because final properties of nanoscale polymeric structures are largely determined by the solid-state microstructure of the confined polymer, it is imperative not only to understand how the microstructure of polymers develops under nanoscale confinement but also to establish means to manipulate it. Here we present a series of processing strategies, adapted from methods used in bulk polymer processing, that allow to control the solidification of polymer nanostructures. Firstly, we show that supramolecular nucleating agents can be readily used to modify the crystallization kinetics of confined poly(vinylidene fluoride) (PVDF). In addition, we demonstrate that microstructural features that are not traditionally affected by nucleating agents, such as the orientation of crystals, can be tuned with the crystallization temperature applied. Interestingly, we also show that high crystallization temperatures and long annealing periods induce the formation of the modification of PVDF, hence enabling the simple production of ferro/piezoelectric nanostructures. We anticipate that the approaches presented here can open up a plethora of new possibilities for the processing of polymer-based nanostructures with tailored properties and functionalities.