# Protocol to perform pressurized blister tests on thin elastic films

## TL;DR

This paper presents a practical protocol for performing pressurized blister tests on thin elastic films, addressing common fabrication challenges and providing a reliable method to measure adhesion energy.

## Contribution

It introduces an easy-to-implement fabrication process for blister test devices and validates the method by measuring adhesion energy of polystyrene on glass.

## Key findings

- Measured adhesion energy of polystyrene on glass: 18 ± 2 mJ/m²
- Validated the blister test method against cleavage test results
- Provided a step-by-step guide for device fabrication and testing

## Abstract

This work aims to identify common challenges in the preparation of the blister test devices designed for measurement of energy release rate for brittle thin films and to propose easy-to-implement solutions accordingly. To this end, we provide a step-by-step guide for fabricating a blister test device comprised of thin polystyrene films adhered to glass substrates. Thin films are first transferred from donor substrates to an air-water interface, which is then used as a platform to locate them on a receiver substrate. We embed a microchannel at the back of the device to evacuate the air trapped in the opening, through which the pressure is applied. We quantify the height and the radius of the blister to estimate the adhesion energy using the available expressions correlating the normal force and the moment with the shape of the blister. The present blister test provided adhesion energy per unit area of $G = 18 \pm 2$ $ \mbox{mJ}/{\mbox m}^2$ for polystyrene on glass, which is in good agreement with the measurement of $G = 14 \pm 2$ $ \mbox{mJ}/{\mbox m}^2$ found in our independent cleavage test.