Poor stability of 3D printed plastic objects in a number of solvents limits several important applications in engineering, chemistry and biology. Due to layered type of assembling, 3D-printed surfaces possess rather different properties as compared to bulk surfaces made by other methods. Here we study fundamental interactions at the solid-liquid interface and evaluate polymeric materials towards advanced additive manufacturing. A simple and universal stability test was developed for 3D printed parts and applied to a variety of thermoplastics. Specific modes of resistance/destruction were described for different plastics and their compatibility to a representative scope of solvents (aqueous and organic) was evaluated. Classification and characterization of destruction modes for a wide range of conditions (including geometry and 3D printing parameters) were carried out. Key factors of tolerance to solvent media were investigated by electron microscopy. We show that the overall stability and the mode of destruction depend on chemical properties of the polymer and the nature of interactions at the solid-liquid interface. Importantly, stability also depends on the layered microstructure of the sample, which is defined by 3D printing parameters. Developed solvent compatibility charts for a wide range of polymeric materials (ABS, PLA, PLA-Cu, PETG, SBS, Ceramo, HIPS, Primalloy, Photoresin, Nylon, Nylon-C, POM, PE, PP) and solvents represent an important benchmark for practical applications.

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The development of new drugs is accelerated by rapid access to functionalized and D-labeled molecules with improved activity and pharmacokinetic profiles. Diverse synthetic procedures often involve the usage of gaseous reagents, which can be a difficult task due to the requirement of a dedicated laboratory setup. Here, we developed a special reactor for the on-demand production of gases actively utilized in organic synthesis (C2H2, H2, C2D2, D2, and CO2) that completely eliminates the need for high-pressure equipment and allows for integrating gas generation into advanced laboratory practice. The reactor was developed by computer-aided design and manufactured using a conventional 3D printer with polypropylene and nylon filled with carbon fibers as materials. The implementation of the reactor was demonstrated in representative reactions with acetylene, such as atom-economic nucleophilic addition (conversions of 19–99%) and nickel-catalyzed S-functionalization (yields 74–99%). One of the most important advantages of the reactor is the ability to generate deuterated acetylene (C2D2) and deuterium gas (D2), which was used for highly significant, atom-economic and cost-efficient deuterium labeling of S,O-vinyl derivatives (yield 68–94%). Successful examples of their use in organic synthesis are provided to synthesize building blocks of heteroatom-functionalized and D-labeled biologically active organic molecules.

Visible light photocatalysis is a rapidly developing branch of chemical synthesis with outstanding sustainable potential and improved reaction design. However, the challenge is that many particular chemical reactions may require dedicated tuned photoreactors to achieve maximal efficiency. This is a critical stumbling block unless the possibility for reactor design becomes available directly in the laboratories. In this work, customized laboratory photoreactors were developed with temperature stabilization and the ability to adapt different LED light sources of various wavelengths. We explore two important concepts for the design of photoreactors: reactors for performing multiple parallel experiments and reactors suitable for scale-up synthesis, allowing a rapid increase in the product amount. Reactors of the first type were efficiently made of metal using metal laser sintering, and reactors of the second type were successfully manufactured from plastic using fused filament fabrication. Practical evaluation has shown good accuracy of the temperature stabilization in the range typically required for organic synthesis for both types of reactors. Synthetic application of 3D printed reactors has shown good utility in test reactions—furan C–H arylation and thiol-yne coupling. The critical effect of temperature stabilization was established for the furan arylation reaction: heating of the reaction mixture may lead to the total vanishing of photochemical effect.