Frontal Conversion and Uniformity in 3D Printing by Photopolymerisation
File(s)
Published version
Author(s)
Vitale, A
Cabral, JT
Type
Journal Article
Abstract
We investigate the impact of the non-uniform spatio-temporal conversion, intrinsic to photopolymerisation, in the context of light-driven 3D printing of polymers. The polymerisation kinetics of a series of model acrylate and thiol-ene systems, both neat and doped with a light-absorbing dye, is investigated experimentally and analysed according to a descriptive coarse-grained model for photopolymerisation. In particular, we focus on the relative kinetics of polymerisation with those of 3D printing, by comparing the evolution of the position of the conversion profile (zf) to the sequential displacement of the object stage (∆z). After quantifying the characteristic sigmoidal monomer-to-polymer conversion of the various systems, with a combination of patterning experiments, FT-IR mapping, and modelling, we compute representative regimes for which zf is smaller, commensurate with, or larger than ∆z. While non-monotonic conversion can be detrimental to 3D printing, for instance in causing differential shrinkage of inhomogeneity in material properties, we identify opportunities for facile fabrication of modulated materials in the z-direction (i.e., along the illuminated axis). Our simple framework and model, based on directly measured parameters, can thus be employed in photopolymerisation-based 3D printing, both in process optimisation and in the precise design of complex, internally stratified materials by coupling the z-stage displacement and frontal polymerisation kinetics.
Date Issued
2016-09-07
Date Acceptance
2016-09-02
Citation
Materials, 2016, 9 (9)
ISSN
1996-1944
Publisher
MDPI
Journal / Book Title
Materials
Volume
9
Issue
9
Copyright Statement
© 2016 by the authors; licensee MDPI, Basel, Switzerland. This article is an open access
article distributed under the terms and conditions of the Creative Commons Attribution
(CC-BY) license (http://creativecommons.org/licenses/by/4.0/).
article distributed under the terms and conditions of the Creative Commons Attribution
(CC-BY) license (http://creativecommons.org/licenses/by/4.0/).
Sponsor
Engineering & Physical Science Research Council (E
Engineering & Physical Science Research Council (EPSRC)
Engineering & Physical Science Research Council (EPSRC)
Identifier
http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000384668700009&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=1ba7043ffcc86c417c072aa74d649202
Grant Number
EP/K503733/1
EP/L022176/1
EP/L020564/1
Subjects
Science & Technology
Technology
Materials Science, Multidisciplinary
Materials Science
3D printing
photopolymerisation
conversion profile
photopolymerisation model
UV curing
CHEMICAL-SYNTHESIS
POLYMERS
ARCHITECTURES
REACTIONWARE
LIGHT
WAVES
03 Chemical Sciences
09 Engineering
Publication Status
Published
Article Number
ARTN 760