02186naa a2200253 a 450000100080000000500110000800800410001902200140006002400270007410000160010124501300011726000090024730000140025652014160027065300290168665300420171565300220175770000200177970000210179970000220182070000200184270000240186277300460188621358882022-11-22       2021    bl uuuu     u00u1 u    #d  a1548-26347 a10.1002/pen.257372DOI1 aREIS, I. A.  aAnnealing and crystallization kinetics of poly(lactic acid) pieces obtained by additive manufacturing.h[electronic resource]  c2021  a2097-2104  aIn this study, we investigated the influence of isothermal treatment of poly(lactic acid) (PLA) 3D printed samples at different crystallization temperatures. In this case, we analyzed the effect of each crystallization temperature on spherulites formation in printed PLA, affecting the final mechanical properties of pieces. For such, the thermomechanical properties, morphological structure, and crystallization kinetics were analyzed before and after thermal treatment. The 3D printed samples were heat treated at 80C, 90C, 100C, 110C, and 119C. With annealing, we observed an improvement in the mechanical PLA properties; however, the exothermic crystallization peak was different for the samples. Pieces before annealing were found to have a low crystallinity index (Ic) of 2%–7%, and the pieces after annealing presented a considerable Ic (27%–34%). Annealing temperatures of 100C, 110C, and 119C produced the fastest crystallization kinetics, while annealing temperatures of 80C and 90C resulted in the lowest crystallization kinetics for complete crystallization. After annealing, improvement in the flexural strength (34%–47%) and Young's modulus (26%–51%) for all annealed pieces occurred. The appropriate condition was observed at 100C, which was the onset temperature of crystallization, owing to the combination of the shorter time of crystallization with the increased mechanical properties  aCrystallization kinetics  aFilament structure-property relations  aThermal annealing1 aCLARO, P. I. C.1 aMARCOMINI, A. L.1 aMATTOSO, L. H. C.1 aSILVA, S. P. da1 aSENA NETO, A. R. de  tPolymer Engineering Sciencegv. 61, 2021.