Citation: Dawan, F.; Givens, M.;
Williams, L.; Mensah, P. Carbonated
3D-Printable Polymer Composite for
Thermo-Mechanically Stable
Applications. J. Manuf. Mater. Process.
2022, 6, 66. https://doi.org/10.3390/
jmmp6030066
Academic Editors: Ludwig Cardon
and Clemens Holzer
Received: 10 May 2022
Accepted: 13 June 2022
Published: 15 June 2022
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Manufacturing and
Materials Processing
Journal of
Article
Carbonated 3D-Printable Polymer Composite for
Thermo-Mechanically Stable Applications
Fareed Dawan * , Melvin Givens, Lakeira Williams and Patrick Mensah
Department of Mechanical Engineering, Southern University and A&M College, Baton Rouge, LA 70813, USA;
melvin.givens@sus.edu (M.G.); lakeira.williams@sus.edu (L.W.); patrick_mensah@subr.edu (P.M.)
* Correspondence: fareed_dawan@subr.edu; Tel.: +1-225-771-2207
Abstract:
In this report, we investigate the infusion of carbon dioxide into a 3D-printable photosen-
sitive polymer. The result is a carbonated polymer composite material. In use, polymer composite
materials expect to succeed where ordinary polymers and metals fail. This is due to the tailorability
of composite materials for specific applications. Usually, micro/nano-particulates are embedded as
fillers within a polymer matrix, enhancing the overall material properties. Here, carbon dioxide (CO
2
)
microbubbles serve as the filler within a nylon-like polymer matrix. Additive manufacturing by
stereolithography (SLA) of the carbonated polymer composite proved possible using the digital light
projection (DLP) 3D printing technique. Post-heat treatment using thermogravimetric analysis of the
samples at elevated temperatures resulted in a 33% mass reduction, indicative of nearly complete
solvent removal and curing. An initial increase in polymer carbonation duration showed a 16%
increase in porosity, more stable thermal profiles, and a 40% decrease in specific heat capacity. Thermo-
mechanical compressive tests on an optimal carbonated sample revealed a 70% increase in compressive
strength over its neat counterpart and a peak modulus at 50
◦
C of 60 MPa. Such 3D-printable carbonated
polymer composites may find use in applications requiring high
strength-to-weight
ratio thermally
stable polymers and applications requiring a versatile and convenient storage medium for on-demand
CO
2
deposition or supercritical fluid phase transformation.
Keywords:
thermomechanical properties; carbonated polymers; additive manufacturing; multi-
functional composites; differential scanning calorimetry (DSC)
1. Introduction
As engineering requirements for materials become stricter, it is imperative that material
selection and processability become more expansive. Composites serve as an effective
approach to this demand since they are tailorable to a myriad of applications. Furthermore,
the option of creating complex shapes from a composite provides an additional expansion
of its use. The intent of this work is to address this material requirement by introducing a
new polymer composite material that can be additively manufactured by 3D printing.
Fundamentally, polymer composites are comprised of two parts: the lightweight
polymer matrix, which constitutes the bulk of the material and functions as the major
load bearer, and the filler, which functions as an enhancement to the matrix. The effective
composition of these materials provides solutions to problems where ordinary polymers
and metals fail. Imparting useful properties such as increased surface area, conductivity,
and the high strength of metal or nonmetal micro- or nano-particulates as fillers into a
polymer matrix creates a versatile, lightweight, easily formable, multifunctional polymer
composite material [
1
–
6
]. In this work, it is suggested that gas molecules can also serve as a
filler within a polymer matrix. This suggestion is largely counter-intuitive since, generally,
pockets of air (gas) or voids in composites and in materials are categorized as defects and
cause adverse effects on the overall material property and performance [
7
,
8
]. Extensive
work goes into the detection of voids and their formation [
9
–
13
]. Even more research is
J. Manuf. Mater. Process. 2022, 6, 66. https://doi.org/10.3390/jmmp6030066 https://www.mdpi.com/journal/jmmp
