A facile and green method to prepare highly luminescent and mechanically robust polylactide-based composites for three-dimensional printing

Polylactide (PLA), a bio-based polymer that is usually derived from renewable crops (e.g., corn and rice), is widely used in three-dimensional (3D) printing. New functional materials based on PLA for 3D printing are highly desirable; however, the traditional routes for preparing functional printable materials were either time-consuming or environmentally unfriendly. Here, we demonstrate for the first time a simple and environmentally friendly method to homogenously disperse functional filler within PLA matrix, by which mechanically robust and highly luminescent SrAl2O4:Eu2+, Dy3+ (SAO)/PLA composite filaments for 3D printing were readily achieved. This method involves the incorporation of only 1% of glycerol (based on the weight of PLA) as a dispersion agent and compatibility agent between hydrophilic SAO and hydrophobic PLA. Consequently, the luminescence intensity of composites increased linearly with SAO content, while 5% of SAO could obtain the maximum strength (60.2 ± 4.9 MPa), 50% higher than that of pure PLA. Moreover, the green method can be used to prepare other kinds of composite functional filaments for 3D printing. •The article was the first to report on a simple and environmentally friendly method to create luminescent filaments.•A good interfacial compatibility between PLA and functional filler was achieved.•Highly luminescent and mechanically robust composites can be printed by FDM using the luminescent filaments.•The 3D-printed parts can be potentially utilized in diverse fields.