Study of the Thermomechanical Properties of Photocured Resins Based on Curable Monomers from PLA and PHB for SLA 3D Printing

Abstract

Biobased curable structures were synthesized from polymers poly(lactic acid) (PLA) and poly(3-hydroxybutyrate) (PHB). The curability of synthesized products and their thermomechanical properties were studied using numerous methods: FT-IR, DSC, DMA, or TGA. The reactivity of all methacrylated esters of lactic and 3-hydroxybutanoic acid was studied via DSC, and the results confirmed that all structures could be cured. The highest activation energy (E a ) was calculated for methacrylated methyl lactate, reaching 134.3 kJ•mol −1 . It was also found that all calculated activation energies had very similar values. Infrared spectroscopy was used for the study of the degrees of cure. Curable alkyl lactates exhibited significantly higher degrees of cure (approximately 95% or more) than curable 3-hydroxybutarytes (around 70%). DMA analysis confirmed that methacrylated lactates showed higher glass transition temperatures (67.1 and 49.4 °C) and storage modulus values at 40 °C (1840 and 1110 MPa) compared to methacrylated 3-hydroxybutyrates (T g of 44.4 °C and lower, and storage modules E′ around 600 MPa). The heat-resistant index calculated for all products proved the same trend: curable lactates exhibited higher heat resistivity (T S of 148.0 and 146.3) than curable 3-hydroxybutyrates (T S of 129.9 and 125.1). Synthesized and studied precursors can serve their particular purposes in fields of curable systems, and the application potential was performed via SLA 3D printing.

Improvements in the Production of Isosorbide Monomethacrylate Using a Biobased Catalyst and Liquid–Liquid Extraction Isolation for Modifications of Oil-Based Resins

“…The graphical illustration of the performed TGA analysis is also shown in Figure c,d. The calculated heat-resistant index is comparable to the previously mentioned methacrylated esters described in a previous article …”

“…The calculated MISD’s activation energy exhibits 94.6 kJ/mol, and the pre-exponential factor (ln­( A ) = 28.78) confirms that synthesized MISD is a reactive monomer. Both mentioned parameters can be compared to synthesized curable monomers from our previous study, which reached considerably higher values . The comparison uncovers that the reactivity of MISD is higher than those of previously introduced and described precursors.…”

“…Both mentioned parameters can be compared to synthesized curable monomers from our previous study, which reached considerably higher values. 56 The comparison uncovers that the reactivity of MISD is higher than those of previously introduced and described precursors.…”

“…The calculated heat-resistant index is comparable to the previously mentioned methacrylated esters described in a previous article. 56 …”

Synthesis and Characterization of Silicon-Modified Polyurethane Acrylate for UV-Thermal Dual Curing in Three Dimensional Printing

“…The evolution of 3D printing technology has made significant strides since Charles Hull introduced early stereolithography (SLA) systems for manufacturing in the 1980s . Currently, SLA and DLP are the two most commonly used 3D printing technologies, representing approximately 43% of the market. , UV-curing 3D printing technology utilizes ultraviolet lasers to scan photosensitive resins layer by layer, enabling the gradual construction of objects. , This technology allows for the independent design and production of intricate parts with high precision and high material efficiency. The photosensitive resin reacts with UV light, triggering a rapid curing process.…”