Page 91 - MSAM-3-2

Materials Science in Additive Manufacturing Sustainable resin for coral restoration

object. In this study, the AESO and HDDA diluent ratio carbon-carbon double bond stretching in the acrylic acid
of 4:1 was found to achieve an optimal combination of within AESO. These signals display a significant reduction
improved flow, reinforced strength of the print, and cost- after the reaction, indicating the successful polymerization
efficient resin utilization, ensuring successful 3D printing of the carbon-carbon double bonds. Moreover, the
outcomes. reduction in peaks at 1406 and 810 cm further confirms
-1
the reduction of double bonds. These signals are associated
3.2. FTIR analysis with the bending of the double bonds. Another noteworthy
-1
The FTIR analysis provides conclusive evidence of the observation is the shift in signals from 1186 to 1159 cm
polymerization of AESO resin after printing (Figure 7). The after the polymerization, corresponding to the C-O-C
observed signals at 1635 to 1618 cm correspond to the oscillation in the ester group. Given the proximity of the
-1
C-O-C group to the double bond, any decrease in the
presence of double bonds would influence the oscillation
pattern of the C-O-C group. 47

3.3. TGA analysis
According to the TGA spectra of the printed AESO and
CCP scaffold shown in Figure 8, it can be observed from the
left spectrum that cured AESO resin starts to decompose
at approximately 350°C and completely burns away at
800°C. The right spectrum shows a 70% weight loss at
48
approximately 400°C. This weight loss corresponds to the
Figure 5. Coral plugs printed in acrylated epoxidized soybean oil resin decomposition of the organic part of the modified CCP
(left) and modified calcium carbonate-photoinitiated resin (right).
resin. On the other hand, calcium carbonate decomposes
at 750 °C, producing carbon dioxide and calcium oxide.
49
The weight loss observed corresponds to 12.6% carbon
dioxide, indicating that calcium carbonate accounts for
approximately 28.7% of the sample’s composition.

3.4. Differential scanning calorimetric analysis
The differential scanning calorimetric spectrum (Figure 9)
reveals that the glass transition temperature of the printed
AESO resin is 48°C. The absence of a distinct sharp
melting peak indicates the high degree of crosslinking in
Figure 6. Resin with diacrylate diluent printed coral plug (on the left) and the printed AESO scaffold and shows the lack of crystalline
resin without diacrylate diluent printed (on the right). domains. 50

Figure 7. Fourier transform infrared spectra of acrylated epoxidized soybean oil (AESO) resin (top) and printed AESO scaffold (bottom).

Volume 3 Issue 2 (2024) 7 doi: 10.36922/msam.3125