Curing-dependent thermo-viscoelastic and shrinkage behaviour of photopolymers. (April 2023)

• Record Type: Journal Article
• Authors: Sekmen, Kubra; Rehbein, Thomas; Johlitz, Michael; Lion, Alexander; Constantinescu, Andrei
• Is Part Of: Mechanics of materials. Volume 179(2023)
• Publication Date: 2023-04
• Subjects: Photopolymer -- Curing -- Viscoelastic constitutive law -- Shrinkage strain; Strength of materials -- Periodicals; Mechanics, Applied -- Periodicals; Résistance des matériaux -- Périodiques; Mécanique appliquée -- Périodiques; Mechanics, Applied; Strength of materials; Periodicals; Electronic journals; 620.11
• DOI: 10.1016/j.mechmat.2023.104566
• Languages: English
• ISSNs: 0167-6636

Abstract

Abstract: This study investigates the influence of curing on the thermo-viscoelastic properties and chemical shrinkage of a commercially available photopolymer resin used in SLA and DLP 3D printing and presents a modelling approach for predicting material properties. UV rheometer and DMA measurements were performed to investigate the viscoelastic properties of the photopolymer material as a function of temperature, degree of cure, and frequency. Time–temperature and time-cure superposition principles were applied to the experimental results. In addition, the chemical shrinkage behaviour was studied by the UV rheometer as a function of the degree of cure and temperature, and a model equation was proposed based on these parameters. Our experimental findings have led to the development of constitutive equations for the complete material behaviour. Highlights: Investigation of viscoelastic properties by UV rheometer and DMA tests. Viscoelastic model based on time-cure and time-temperature superpositions. Chemical shrinkage expressed as a function of curing and temperature. Prediction of final mechanical properties in terms of photocuring parameters.