PLA/PHBV共混3D打印线材的制备及性能研究

Study on Preparation and Properties of PLA/PHBV 3D-Printing Filament

采用熔融共混法制备了聚乳酸/聚(3-羟基丁酸-co-3-羟基戊酸酯)(PLA/PHBV)共混物,用熔融沉积成型(FDM)技术制备了三维(3D)打印标准测试样条,研究了PLA/PHBV质量比对PLA/PHBV共混物及3D打印线材性能的影响。结果表明,PLA/PHBV共混材料是完全不相容的体系,随着PHBV含量的增加,PLA/PHBV共混物以及3D打印制品的拉伸强度下降,但断裂伸长率有所提高;弯曲强度及冲击强度均先上升后下降;注塑样品的拉伸强度最大可达43.31 MPa,断裂伸长率可达5.37%;3D打印制品的拉伸强度最大可达49.16 MPa,断裂伸长率可达7.41%;PLA/PHBV共混物以及3D打印制品淬断断面呈现典型的"海岛"分布,PHBV相均匀的分散在PLA基中;随着PHBV含量的增加,注塑样条的断面逐渐变得粗糙,打印制品层与层之间空隙减小,填充率上升,黏结性能提高。

Polylactic acid(PLA)/poly(3-hydroxybutyric acid-co-3-hydroxyvalerate)(PHBV) blends were prepared by melt blending, and then the 3 D printing standard samples were prepared by a fused deposition modeling(FDM) method. The effect of mass ratio of PLA and PHBV on the 3 D printing performance was investigated. The results indicated that the PLA/PHBV blends were completely incompatible. The tensile strength of the blends and their 3 D printed specimens decreased compared to pure resin, but their elongation at break increased with the addition of PHBV. The bending strength the impact strength of the blends were found to increase at first and then to decrease. The injection molded samples achieved the maximum tensile strength up to 43.31 MPa and the maximum elongation at break of 5.37 %. The 3 D printed specimens exhibited the maximum tensile strength up to 49.16 MPa and the elongation at break of 7.41 %. Scanning electron microscopy revealed that there was a typical ‘island’ distribution in the quenched sections of the blends and their 3 D printed specimens, in which the PHBV phase was uniformly dispersed in the PLA matrix. With the increase of PHBV content, the cross section of the injection molded samples became rougher and the gap between the layers of the 3 D printed specimens became smaller. This led to an increase in filling rate and an improvement in bonding performance.