A Study on Release Property through Self Coating in LSR Injection Process

Baeg-Soon  Cha; Yong-Jun  Jeon; Jeong-Won  Lee; Hyung-Pil  Park; Sang-Gweon  Kim

doi:10.4236/ampc.2015.57024

Sang-Gweon Kim, Hyung-Pil Park, Jeong-Won Lee, Yong-Jun Jeon, Baeg-Soon Cha^*

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.

Keywords: Multi-Component-Injection Molding (MCM) Method, Liquid-Silicone-Rubbers (LSRs), Peeling Test, Self Coating, Surface Analysis, Sessile Water Drop Contact Angle Tests

Cite this paper: Kim, S. , Park, H. , Lee, J. , Jeon, Y. and Cha, B. (2015) A Study on Release Property through Self Coating in LSR Injection Process. Advances in Materials Physics and Chemistry, 5, 229-243. doi: 10.4236/ampc.2015.57024.

References

[1] Siahkali, A.G., Mitra, S., Kingshott, P., Almdal, K., Bloch, C. and Rehmeier, H.-K. (2005) Investigation of the Hydro-thermal Stability of Cross-Linked Liquid Silicone Rubber (LSR). Polymer Degradation and Stability, 90, 471-480.
http://dx.doi.org/10.1016/j.polymdegradstab.2005.04.016

[2] Kühr, C., Sporrerand, A. and Altstadt, V. (2013) Determination of Adhesion between Thermoplastic and Liquid Silicone Rubbers in Hard-Soft-Combinations via Mechanical Peeling Test. Proceedings of the Polymer Processing Society 29th Annual Meeting, Nuremberg, 15-19 July 2013, S04-poster.

[3] Wang, F., Li, Y.N. and Wang, D. (2013) Adhesion Enhancement for Liquid Silicone Rubber and Different Surface by Organosilane and Pt Catalyst at Room Temperature. Bulletin of Materials Science, 36, 1013-1017.
http://dx.doi.org/10.1007/s12034-013-0575-8

[4] Roth, J., Albrecht, V., Nitschke, M., Bellmann, C., Simon, F., Zschoche, S., Michel, S., Luhmann, C., Grundke, K. and Voit, B. (2008) Surface Functionalization of Silicone Rubber for Permanent Adhesion Improvement. Langmuir, 24, 12603-12611,
http://dx.doi.org/10.1021/la801970s

[5] Jing, S.-Y. and Lee, H.-J. (2002) Chemical Bond Structure on Si-O-C Composite Films with a Low Dielectric Constant Deposited by Using Inductively Coupled Plasma Chemical Vapor Deposition. Journal of the Korean Physical Society, 41, 769-773.

[6] ASTM D 3163-01 (2001) Standard Test Method for Determining Strength of Adhesively Bonded Rigid Plastic Lap-Shear Joints in Shear by Tension Loading. Annual Book of ASTM Standards, Vol. 15.06.

[7] Kinloch, A.J. (1987) Adhesion and Adhesives: Science and Technology. Chapman and Hall, London.
http://dx.doi.org/10.1007/978-94-015-7764-9

[8] Charmeau, J.-Y., Chailly, M., Gilbert, V. and Béreaux, Y. (2008) Influence of Mold Surface Coatings in Injection Molding. Application to the Ejection Stage. International Journal of Material Forming, 1, 699-702.
http://dx.doi.org/10.1007/s12289-008-0311-x