UV assisted photo reactive polyether‐polyesteramide resin for future applications in 3D printing

Abstract

Among additive manufacturing, photocuring 3D printing technologies are very relevant because of its high printing speed and high precision. However, the limited performance of photosensitive thermoset polymers is the bottleneck for the application of photocuring 3D printing in some fields, particularly in the biomedical sector. Thus, the development of biodegradable and biocompatible materials is highly desirable and of utmost importance. In this work, a biodegradable and non-cytotoxic thermoset polymer for photocuring 3D printing is reported. It consists of an unsaturated polyesteramide bearing phenylalanine, 2-butene-1,4-diol and fumarate building blocks, which is photocured under UV irradiation using a low molecular weight poly(ethylene glycol) diacrylate as crosslinker. The main characteristics of the new thermoset are:(1) very high volumetric and mechanical integrity stabilities, comparable to that of photocured epoxides; (2) very high degradation temperature; (3) very low water absorption capacity; (4) relatively fast enzymatic degradation, reaching 16.5% after 3 months; and (5) non-cytotoxic response in presence of epithelial cells, even when soluble molecular fragments coming from biodegradation are considered. These properties favor the future utilization of the new polyether-polyesteramide resin in the manufacturing of more sustainable products via 3D printing methods, such as stereolithography, that uses UV sources.

Fumarate‐co‐PEG‐co‐sebacate photopolymer and its evaluation as a drug release system

“…This is not surprising given the difference in reactivity expected for FA and SA. For instance, similar results were observed for the synthesis of polyesters derived from FA and succinic acid 9,10 . Given that SA is more reactive than FA, it is reasonable to expect that FA–PEG–SA copolymer has a higher SA content, at least at the beginning of the polyesterification reaction.…”

“…For instance, similar results were observed for the synthesis of polyesters derived from FA and succinic acid. 9,10 Given that SA is more reactive than FA, it is reasonable to expect that FA-PEG-SA copolymer has a higher SA content, at least at the beginning of the polyesterification reaction. On other hand, oligomers with FA-PEG-FA structure, could be eliminated during the washes with dichloromethane, previous to NMR analysis.…”

“…Other well-known approaches for crosslinking of polyesters involve the (met)acrylation of free hydroxyl groups and the inclusion of unsaturated α,β-carboxylic monomers, such as fumaric acid (FA), which allows crosslinking by radical reactions at the level of the double bonds, yielding new and stable C C linkages. 9 This second approach probed to be useful for crosslinking linear unsaturated polyesters, such as poly(1,n-diol fumarate) and itaconate polyesters. 10,11 In these cases crosslinking occur by thermal or light induced radical reactions, which usually require the use of appropriate initiators.…”

“…This procedure often requires the exposure to high temperature (120°C) and long periods of time (even days), to achieve networks which have better mechanical properties and degradation profiles compared with the un‐crosslinked precursors. Other well‐known approaches for crosslinking of polyesters involve the (met)acrylation of free hydroxyl groups and the inclusion of unsaturated α,β‐carboxylic monomers, such as fumaric acid (FA), which allows crosslinking by radical reactions at the level of the double bonds, yielding new and stable CC linkages 9 . This second approach probed to be useful for crosslinking linear unsaturated polyesters, such as poly(1,n‐diol fumarate) and itaconate polyesters 10,11 .…”

Itaconic-Acid-Based Sustainable Poly(ester amide) Resin for Stereolithography

“…The resulting photocurable ink, obtained after the combination of the prepolymer with photopolymerization initiators/inhibitors, cross-linkers, and dyes, showed a good printability resolution in reasonable time scales, together with a total biobased content of as high as 96.5%. In the same way, several studies focused on the synthesis and application of poly­(ester amide)­s for additive manufacturing. − The introduction of diamines into the synthetic pathway results in the formation of amide moieties in the polymer backbone, that can confer to the 3D printed material an improved biodegradation rate and processability, together with the desired mechanical properties . In particular, itaconic-acid-based poly­(ester amide)­s have not been widely investigated yet due to the possible occurrence of an aza-Michael attack of the diamine to the α,β-unsaturated double bond of the acid.…”