Effect of Aluminum Flakes on Mechanical and Optical Properties of Foam Injection Molded Parts

• Published in: Polymers Vol. 13; no. 17; p. 2930
• Main Authors: Kim, Donghwi, Ryu, Youngjae, Lee, Ju-Heon, Cha, Sung Woon
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 30.08.2021; MDPI
• Subjects: Aluminum; Aluminum flakes; conventional injection molding; foam injection molding; Gases; Gloss; Impact strength; Injection molding; Mechanical properties; metallic texture; Methods; Modulus of rupture in bending; Nitrogen; Optical properties; Orientation effects; Pigments; Polymers; Rare gases; reflectance; Silver; Weight reduction; Japan
• ISSN: 2073-4360; 2073-4360
• DOI: 10.3390/polym13172930

Injection research using aluminum flakes has been conducted to realize metallic textures on the surface of plastic products. Several studies have focused on the effect of the orientation and quality of the flakes when using conventional injection molding methods; however, limited studies have focused on the foam injection molding method. In this study, we examined the orientation of aluminum flakes through foam injection with an inert gas and observed the changes in texture using a spectrophotometer and a gloss meter. The mechanical properties were also studied because the rigidity of the product, which is affected by the weight reduction that occurs during foaming, is an important factor. The results demonstrate that under foam injection molding, reflectance and gloss increased by 6% and 7 GU, respectively, compared to those obtained using conventional injection molding; furthermore, impact strength and flexural modulus increased by 62% and 15%, respectively. The results of this research can be applied to incorporate esthetic improvements to products and to develop functional parts.