Injection molding binder system

In 1997, Lenk et. al. described a thermoplastic binder system consisting of polyethylene, paraffin, wax and surfactants p enk 97]. Various binder components for injection molding, extrusion and hot molding were tested for the fabrication of bars, tubes, discs, rings and balls of SiC-platelet-reinforced SiC composites. Good alignment of the SiC platelets in the matrix made it possible to improve the densification of the composite. 

Ebe93] Ebenhdch, J ter Maat J (1993) Ceramic Injection Molding with a Polyacrylat Based Binder System. In Advances of Powder Metallurgy and Particulate Materials, vol 5, Powder Injection Molding. Metall Powder Industires Federation, Princeton, pp 73-89... 

Various binder systems have been used in ceramic injection molding, which can be classified into five types (i) thermoplastic compounds, (ii) thermosetting compounds, (iii) water-based systems, (iv) gelation systems, and (v) inorganics. Among these, thermoplastic compounds are the most widely used and understood, which are mainly commercial polymers. The ratio of powder to binder is a key parameter. 

Table 6.13 Thermoplastic Binder Systems for Ceramic Injection Molding...

Practical binder systems, particularly in the case of injection molding, consist of at least two components that diffa in their volatility and decomposition behavior. A key to efficient debinding is to select components that do not have a significant ovCTlap between the tempaature ranges for removal. In this case. 

Vector SBS, SIS, and SB styrenic block copolymers are produced as diblock-free and diblock copolymers. The company s process to make linear SBCs yields virtually no diblock residuals. Residual styrene butadiene and styrene isoprene require endblocks at both ends of the polymer to have a load-bearing segment in the elastomeric network. However, diblocks are blended into the copolymer for certain apphcations. Vector SBCs are injection molded, extruded, and formulated into pressure-sensitive adhesives for tapes and labels, hot-melt product-assembly adhesives, construction adhesives, mastics, sealants, and asphalt modifiers. The asphalts are used to make membranes for single-ply roofing and waterproofing systems, binders for pavement construction and repair, and... 

Preceramic polymers have the potential to improve traditional ceramic processing methods (2). In particular, ceramic injection molding may be enhanced by the replacement of organic binders with thermosetting polysilazanes. Table II compares the attributes of the two binder systems. 

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