Optimising Photothermal Silver Nanoparticles for Efficient Light-Activated Shape Memory Response in AgNP-Polymer Composites

TL;DR

This paper reports on the synthesis of silver nanoparticles optimized for light-induced heating, integrated into a polymer to create a shape memory material activated by UV-blue light, with detailed characterization and performance evaluation.

Contribution

It introduces a microwave-assisted synthesis method for AgNPs with controlled size and distribution, enhancing photothermal response in shape memory composites.

Findings

Smaller AgNPs showed better photothermal efficiency.

Optimal PVP molecular weight and AgNO3/PVP ratio improved light absorption.

The composite demonstrated reliable light-activated shape memory behavior.

Abstract

The study presents the synthesis and integration of silver nanoparticles (AgNPs) into a polyurethane (PU) matrix to create a light-activated shape memory polymer (SMP). AgNPs were synthesized using a microwave-assisted solvothermal method with polyvinylpyrrolidone (PVP) as a stabilizer, where varying the molecular weight of PVP and the AgNO3/PVP ratio influenced nanoparticle size and distribution. Characterisation via scanning electron microscopy (SEM) and dynamic light scattering (DLS) confirmed the irregular morphology and size consistency of AgNPs, with smaller particles exhibiting narrow size distributions and enhanced photothermal response. Among the samples, PVP with an average molecular weight (Mn) of 10,000 and an AgNO3/PVP mole ratio of 14.7 demonstrated optimal UV-blue light absorption, which facilitated efficient local heating under irradiation. The AgNP-PU composite exhibited a reliable shape memory effect when exposed to UV-blue light.