Fig 1.
Objects of various shapes made of PLA by 3D printing.
(A) cylinder, (B) cone, (C) sphere, (D) joined cylinder/cone, (E) pyramid, (F) cube.
Fig 2.
Evaluation of quality of 3D-printed shapes.
(A) cylindrical test tube, (B) hollow entity of cubical shape, (C) spherical flask. In the top view, arrows indicate outgassing.
Fig 3.
Experimental demonstration of sealing properties of 3D-printed tube at different k-values.
(A-F)–Evaluation of the of the number of pores in the wall of the tubes manufactured at different k-values; (G-I)–schematic representation of the effect of k-value on the porosity; (J, K)–electron microscopy image of the outer surface of an object printed at k = 0.85 showing a perforating pore (K); (L, M)—electron microscopy image of the outer surface of an object printed at k = 0.98 showing a smaller pore filled with polymer (M).
Fig 4.
Functional assessment of 3D printing quality for objects of different shapes.
All objects are printed with identical parameters at k = 0.9 from PLA: (A) cylinder, (B) cone, (C) sphere, (D) compound shape, (E) pyramid, (F) cube. The diagrams below show the distribution/densities of the pores. Red areas have maximal porosity/permeability; green areas are relatively impermeable; blue color designates junctions with the air compressor.
Fig 5.
Printed cylindrical tubes of different wall thickness (l, mm).
For each l value the corresponding wall structure and printing quality are displayed (all items were printed at k = 0.98).
Fig 6.
Operational reliability of 3D printed polypropylene tubes.
PP tubes as chemical reaction vessels in comparison with conventional glass test tubes. Values of k are given below for each 3D-printed tube. Performance in the studied chemical transformation is illustrated by product yield (in %) in each studied case, where ≥ 90% efficiency corresponds to excellent performance.
Fig 7.
Suzuki-Miyaura reaction.
Fig 8.
Heck reaction.
Fig 9.
Protons in the molecules of reagents and products for conversion calculation by NMR study.