Interfaces during multi-polymer injection moulding
Injection molding techniques are increasingly applied to produce plastics components. This fact is mainly boosted by newly developed technical variants, or so-called special technologies. In this respect, multicomponent techniques are of major importance. Applying these techniques, a polymer is linked to another polymer (i.e. by multi-polymer injection molding), or to another type of material, for instance metal. One of the targets here is to combine properties, so that component requirements are best fulfilled. The quality of the joint is determined as early as during selection of the appropriate material combinations. It is therefore crucial to know the character of the interfaces resulting from processing, and the mechanisms involved, as well the interaction that takes place between influencing factors.
This Ph.D. thesis therefore presents a detailed analysis of the major influencing factors. The investigations were conducted on the basis of standard and multi-polymer injection molding techniques, as well as the two types of interface (hot: weld line, cold: two-shot interface). Material and process parameters were varied and their impact on adhesion bonding examined. Additionally, the complex interaction between shape variations and the resulting changes in heat transport conditions were investigated. The paper’s theoretical section eventually uses the findings obtained from the experiments to define the initial and boundary conditions of a two-dimensional mathematical model. As a result, the courses of cooling and temperature equalization relevant for the interface could be determined. The major focus is on the locally different heat transition conditions adjusting during the individual process stages. This analysis of influencing factors will help optimize process control in a well-aimed way, thus improving the strength of the bond.Lesen Sie die deutsche Zusammenfassung auf Kunststoffe.de
Thermoplast, Multi-component injection molding, Multi-polymer injection molding, Interface, Weld line, Adhesion, Bonding strength, Thermal conductivity, Heat transfer
Institute / chair: Fakultät für Maschinenbau der Technischen Universität Chemnitz
Technical consultant for expert services: Prof. Dr.-Ing. Günter Mennig (Betreuer), Prof. Dr.-Ing. Ernst Schmachtenberg, Prof. Dr.-Ing. Bernd Platzer
Publication year: 2005
Provider: Wissenschaftlicher Arbeitskreis Kunststofftechnik (WAK) / Kunststoffe.de
About the PhD Dissertation Data Base
In cooperation with the Wissenschaftlicher Arbeitskreis Kunststofftechnik (WAK), we provide free access to current dissertations in the field of plastics technology.