Neutral-cluster implantation in polymers by computer experiments

TL;DR

This study uses advanced molecular dynamics simulations to investigate how gold nanoclusters implant into Polydimethylsiloxane, revealing significant surface modifications and effects on subsequent cluster penetration.

Contribution

It provides the first detailed atomistic simulation analysis of single nanocluster impacts on realistic polymer substrates, including temperature, pressure, and morphological changes.

Findings

Cluster impact alters local temperature and pressure.

Crater size correlates with cluster energy.

Surface modifications influence future cluster penetration.

Abstract

In this work we perform atomistic model potential molecular dynamics simulations by means of state-of-the art force-fields to study the implantation of a single Au nanocluster on a Polydimethylsiloxane substrate. All the simulations have ben performed on realistic substrate models containing up to 4.6 millions of atoms having depths up to 90 nm and lateral dimensions up to 25 nm. We consider both entangled-melt and cross-linked Polydimethylsiloxane amorphous structures. We show that even a single cluster impact on the Polydimethylsiloxane substrate remarkably changes the polymer local temperature and pressure. Moreover we observe the presence of craters created on the polymer surface having lateral dimensions comparable to the cluster radius and depths strongly dependent on the implantation energy. Present simulations suggest that the substrate morphology is largely affected by the cluster impact and that most-likely such modifications favor the the penetration of the next impinging clusters.