Modeling the Enhanced Efficacy and Curing Depth of Photo-Thermal Dual Polymerization in Metal (Fe) Polymer Composites for 3D Printing.

Jui-Teng Lin,Kuan-Han Lin,Jacques Lalevee,Yi-Ze Lee,Da-Chuan Cheng,Chia-Hung Kao

doi:10.3390/polym14061158

Abstract

This article presents, for the first time, the efficacy and curing depth analysis of photo-thermal dual polymerization in metal (Fe) polymer composites for 3D printing of a three-component (A/B/M) system based on the proposed mechanism of our group, in which the co initiators A and B are Irgacure-369 and charge–transfer complexes (CTC), respectively, and the monomer M is filled by Fe. Our formulas show the depth of curing (Zc) is an increasing function of the light intensity, but a decreasing function of the Fe and photoinitiator concentrations. Zc is enhanced by the additive [B], which produces extra thermal radical for polymerization under high temperature. The heat (or temperature) increase in the system has two components: (i) due to the light absorption of Fe filler and (ii) heat released from the exothermic photopolymerization of the monomer. The heat is transported to the additive (or co-initiator) [B] to produce extra radicals and enhance the monomer conversion function (CF). The Fe filler leads to a temperature increase but also limits the light penetration, leading to lower CF and Zc, which could be overcome by the additive initiator [B] in thick polymers. Optimal Fe for maximal CF and Zc are explored theoretically. Measured data are analyzed based on our derived formulas.

Highlights

In supporting our recent measured data, Bonardi et al [17] and Ma et al [18,19], this article will present the kinetics, the conversion profiles features, and the depth of curing of a three-component (A/B/M) system based on the proposed mechanism of our group [19]
H is the heat in the monomer due to two components: (i) the aFI(z,t) term, due to light absorption of iron filler given by the absorption constant (a), light intensity (I), and iron concentration (F); and (ii) the heat released from the exothermic photopolymerization of the monomer and (iii) the heat transport to the co-initiator, B
We will focus on comprehensive analysis for special features and the key factors of dual radical enhancement for efficient conversion related to the measured data of Ma et al [19], based on the analytic formulas to be derived as follows

Summary

Introduction

This article presents, for the first time, the efficacy and curing depth analysis of photothermal dual polymerization in metal (Fe) polymer composites for 3D printing of a three-component (A/B/M) system based on the proposed mechanism of our group, in which the co initiators A and B are Irgacure-369 and charge–transfer complexes (CTC), respectively, and the monomer M is filled by. Zc is enhanced by the additive [B], which produces extra thermal radical for polymerization under high temperature. The heat is transported to the additive (or co-initiator) [B] to produce extra radicals and enhance the monomer conversion function (CF). The Fe filler leads to a temperature increase and limits the light penetration, leading to lower CF and Zc, which could be overcome by the additive initiator [B] in thick polymers.

Methods

Results

Conclusion