Analysis of the Compression Behaviour of Reinforced Photocurable Materials Used in Additive Manufacturing Processes Based on a Mask Image Projection System

Mask image projection based on stereolithography is an additive manufactured technology based on a Frontal Photopolymerization Process. Therefore, photocurable resins are used to build-up parts layer by layer. In this paper, alumina particles have been used as a reinforcement filler in order to improve the material stress-strain behaviour. In addition, the increment of the photoconversion ratio is a key factor to enhance the mechanical properties. Consequently, a numerical model has been used to determine the optimal printing parameters to enhance the elastic mechanical properties of printed parts according to the characteristics of photocurable materials. Stable and homogeneous reinforced materials have been obtained with an alumina content ranging from 5 to 15 wt%. Furthermore, the compression behaviour of reinforced materials has been analysed by means of experimental tests. The results show an enhancement of mechanical properties after the addition of reinforcement fillers, obtaining a maximum improvement in 10 wt% of solid load content. Finally, the influence of the sample’s orientation on the construction platform has been discussed.

Effect of Ethanol Composition in Water Coagulation Bath on Structure and Performance of Homogeneous-Reinforced Polyvinyl Chloride Hollow Fiber Membranes

Homogeneous-reinforced (HR) polyvinyl chloride (PVC) hollow fiber membranes consisting of coating layer and matrix layer were fabricated via coating process. The mixtures of polymer solutions were uniformly coated on the homogeneous PVC matrix membrane which was prepared by melt-spinning method. The influences of ethanol composition in water coagulation bath on structure and performance of HR membranes were investigated. The results showed that the pure water flux of the HR PVC hollow fiber membranes increased with the increase of ethanol weight fraction in coagulation bath, while the porosity changed slightly. The increase of ethanol weight fraction in coagulation bath brought about the decrease of the protein permeation flux and rejection rate. The tensile strength of HR PVC hollow fiber membranes was about 9.5 MPa, while the elongation at break was higher than 97 %.