TITLE:
A Study on Release Property through Self Coating in LSR Injection Process
AUTHORS:
Sang-Gweon Kim, Hyung-Pil Park, Jeong-Won Lee, Yong-Jun Jeon, Baeg-Soon Cha
KEYWORDS:
Multi-Component-Injection Molding (MCM) Method, Liquid-Silicone-Rubbers (LSRs), Peeling Test, Self Coating, Surface Analysis, Sessile Water Drop Contact Angle Tests
JOURNAL NAME:
Advances in Materials Physics and Chemistry,
Vol.5 No.7,
July
31,
2015
ABSTRACT: This study explores the molding processes by using the Multi-component-injection molding (MCM) method, in which monolithic products are molded by attaching mixed liquid-silicone-rubbers (LSRs) to polybutylene terephthalate (PBT) that has the characteristic of self-binding while burning due to Pt catalysts. It is seen that this method increases the binding force between LSR and PBT. The surfaces coated with Polytetrafluoroethylene (PTFE), Cr, Ni, etc. have excellent peeling with plastic and such surfaces are compared with those treated with hot forging die and micro blasting without coating. When peeling tests are performed at the specified polymerization temperature and molding time after LSR molding on these surfaces of hot working die molds without coating, these surfaces show excellent peeling of molds and LSR products. In particular, they show better peeling after micro blasting than surfaces with Cr and Ni coating as well as surfaces without coating, and the peeling strength also decreases. The results of contact angle and XPS analysis indicate that the LSR binding force is enhanced as an effect of catalysts, though it is not found by SEM. According to the XPS analysis, the structures of the surfaces are close to methyl and vinyl materials that are produced while LSR molding.