Dr. Dmitri Kopeliovich
Polymer Infiltration and Pyrolysis (PIP) is the method of fabrication of Ceramic Matrix Composites comprising an infiltration of a low viscosity polymer into the reinforcing ceramic structure (e.g. fabric) followed by pyrolysis: heating the polymer precursor in the absence of oxygen when it decomposes and converts into a ceramic.
The Ceramics produced from polymers by pyrolysis are called polymer derived ceramics.
Preceramic polymers (polymer precursors) are the Polymers, which can be converted into Ceramics by pyrolysis.
Molecules of preceramic polymers are commonly contain carbon (C) and/or silicon (Si) but may also contain nitrogen (N), oxygen (O), boron (B), aluminum (Al), titanium (Ti).
Polymer Infiltration and Pyrolysis (PIP) technique is used mainly for fabrication Composites with silicon carbide (SiC) matrices from polycarbosilanes (silicon derived polymer precursors): polymethylsilane (PMS) and allhydridopolycarbosilane. The yield of SiC of the precursors is about 65%.
Polysilazane may be converted into SiCN or Si3N4 with ceramic yield up to 90%.
Carbon matrices composites are fabricated by pyrolysis of either carbon thermosetting resins (phenolics, ruran resin, oxidized polystyrene, polyvinyl alcohol) or thermoplastic resins (pitches or coal tar). The carbon yield of these resins is 50-60%.
Advantages of Polymer Infiltration and Pyrolysis (PIP):
The disadvantages of the Polymer Infiltration and Pyrolysis (PIP):