熔融沉积成型参数对改性聚乳酸冲击性能的影响

Influence of Fused Deposition Modeling Processing Parameters on Impact Properties of Modified Poly(lactic acid)

以聚乳酸(PLA)为基体、热塑性聚氨酯(TPU)和甲基丙烯酸甲酯-有机硅-苯乙烯共聚物(S-2001)为增韧剂,通过熔融共混法制备了改性PLA 3D打印线材,采用正交试验探索了底板温度、打印温度、沉积方式、打印层厚和打印速度等熔融沉积成型(FDM)参数对改性PLA冲击性能的影响。结果表明,当底板温度为90℃,喷嘴温度为190℃,沉积方式为45°/45°,打印层厚为0.4 mm和打印速度为45 mm/s时,FDM试样的冲击强度达到最大值,而且打印层厚和沉积方式对改性PLA FDM试样的冲击性能影响显著;扫描电镜分析表明增加打印层厚有利于材料吸收冲击功,奇数层与偶数层之间的不同沉积角度对试样冲击强度的提高影响不一,45°/45°为宜;同时,最优工艺的FDM试样的冲击强度比注塑试样低,为注塑试样的71.4%。

The modified poly(lactic acid)(PLA)filaments were prepared by melt mixing.The influence of fused deposition modeling(FDM)processing parameters on the impact properties of modified PLA were investigated by orthogonal test,including bed temperature,nozzle temperature,deposition style,layer thickness and printing speed.The results indicate that the impact strength of FDM specimen is the greatest with the processing parameters as follows:bed temperature of 90℃,nozzle temperature of 190℃,deposition style of 45°/45°,layer thickness of 0.4 mm and printing speed of 45 mm/s.Furthermore,the layer thickness and the deposition style have a significant effect on the impact properties of modified PLA FDM specimen.The SEM images show that increasing layer thickness is favor of absorbing energy when the materials were impacted.Different deposition angles between odd and even number layers have different effects on the increase of impact strength,and 45°/45°is appropriate.Meanwhile,compared with injection molding,the impact strength of FDM specimen is lower,just 71.4%as high as that of injection molding specimen.