6533b7ddfe1ef96bd127535a
RESEARCH PRODUCT
Absorption kinetics and swelling stresses in hydrothermally aged epoxies investigated by photoelastic image analysis
Michele ScafidiGiuseppe SpadaroMaria Di FilippoGiuseppe PitarresiSabina AlessiClaude Billaudsubject
Absorption of waterMaterials sciencePhotoelastic stress analysiPolymers and PlasticsThermosetting polymerSwelling stresseSettore ING-IND/14 - Progettazione Meccanica E Costruzione Di MacchineDesorptionMaterials ChemistrymedicineComposite materialSettore ING-IND/15 - Disegno E Metodi Dell'Ingegneria IndustrialeCuring (chemistry)chemistry.chemical_classificationHydrothermal ageingPolymerEpoxyCondensed Matter PhysicschemistryMechanics of Materialsvisual_artThermosetting resinvisual_art.visual_art_mediumGravimetric analysisSettore CHIM/07 - Fondamenti Chimici Delle TecnologieSwellingmedicine.symptomdescription
Abstract The present work proposes an experimental optical methodology able to measure the transient swelling stresses induced by the water uptake ageing of polymers. In particular, the work describes the implementation of a Photoelastic technique to quantify internal stresses arising during the hydrothermal ageing of cast epoxy samples. The material investigated is a model DGEBA/DDS epoxy system. Curing and post-curing cycles have been optimised in order to obtain a fully cured, high T g , and completely stress free initial condition. Rectangular beam samples were then left in a hydrothermal bath at 90 °C, and regularly monitored by gravimetric and photoelastic analyses. The quantitative evolution of stresses induced by water ingress was obtained by a Photoelastic Stress Analysis technique applied during water absorption, and successive desorption in controlled conditions. The evolution of stresses is correlated with gravimetric data, allowing to gain a new insight to investigate the complex swelling and diffusion kinetics of water ingress into thermoset polymer networks.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2015-01-01 |