Novel Poly(Caprolactone)/Epoxy Blends by Additive Manufacturing
Novel Poly(Caprolactone)/Epoxy Blends by Additive Manufacturing
复制标题
DOI：
10.3390/ma13040819
复制
发表时间：
2020-02-02
期刊：
影响因子：
3.4
通讯作者：
Pegoretti, Alessandro
中科院分区：
文献类型：
--
作者：
Dorigato, Andrea;Rigotti, Daniele;Pegoretti, Alessandro
这项工作的目的是开发一种具有新型生产技术的热塑性/热固性组合系统。聚（己内酯）（PCL）结构已被设计和生产的熔融长丝制造，并浸渍与环氧树脂基体。将该共混物（EP-PCL（3D））的机械性能、断裂韧性和热愈合能力与常规熔融混合的聚（己内酯）/环氧共混物（EP-PCL）的机械性能、断裂韧性和热愈合能力进行比较。在EP-PCL样品中的环氧树脂内的PCL域的精细分散是负责的一个显着的增韧效果，而在EP-PCL（3D）结构中的两相表现出独立的行为，并在环氧树脂中的断裂扩展是由PCL域的逐步屈服。EP-PCL（3D）系统的这种特殊行为允许PCL相在冲击条件下表现出其作为能量吸收剂的全部潜力。EP-PCL（3D）样品的断裂表面上的光学显微镜图像显示，在断裂韧性测试过程中，裂纹主要在环氧相内传播，而PCL通过塑性变形促进能量吸收。由于共混物中选定的PCL浓度（35体积%）以及成分机械性能之间的差异，两种系统的愈合效率值相当有限。
The aim of this work was the development of a thermoplastic/thermosetting combined system with a novel production technique. A poly(caprolactone) (PCL) structure has been designed and produced by fused filament fabrication, and impregnated with an epoxy matrix. The mechanical properties, fracture toughness, and thermal healing capacities of this blend (EP-PCL(3D)) were compared with those of a conventional melt mixed poly(caprolactone)/epoxy blend (EP-PCL). The fine dispersion of the PCL domains within the epoxy in the EP-PCL samples was responsible of a noticeable toughening effect, while in the EP-PCL(3D) structure the two phases showed an independent behavior, and fracture propagation in the epoxy was followed by the progressive yielding of the PCL domains. This peculiar behavior of EP-PCL(3D) system allowed the PCL phase to express its full potential as energy absorber under impact conditions. Optical microscope images on the fracture surfaces of the EP-PCL(3D) samples revealed that during fracture toughness tests the crack mainly propagated within the epoxy phase, while PCL contributed to energy absorption through plastic deformation. Due to the selected PCL concentration in the blends (35 vol %) and to the discrepancy between the mechanical properties of the constituents, the healing efficiency values of the two systems were rather limited.