The term preceramic polymer refers to one of various polymeric compounds, which through

pyrolysis The pyrolysis (or devolatilization) process is the thermal decomposition of materials at elevated temperatures, often in an inert atmosphere. It involves a change of chemical composition. The word is coined from the Greek-derived elements ''py ...

under appropriate conditions (generally in the absence of oxygen) are converted to ceramic compounds, having high thermal and chemical stability. Ceramics resulting from the

of preceramic polymers are known as

polymer derived ceramics Polymer derived ceramics (PDCs) are ceramic materials formed by the pyrolysis of preceramic polymers, usually under inert atmosphere. The compositions of PDCs most commonly include silicon carbide (SiC), silicon oxycarbide (SiOxCy), silicon nitrid ...

, or PDCs. Polymer derived ceramics are most often

silicon Silicon is a chemical element with the symbol Si and atomic number 14. It is a hard, brittle crystalline solid with a blue-grey metallic luster, and is a tetravalent metalloid and semiconductor. It is a member of group 14 in the periodic ta ...

based and include

silicon carbide Silicon carbide (SiC), also known as carborundum (), is a hard chemical compound containing silicon and carbon. A semiconductor, it occurs in nature as the extremely rare mineral moissanite, but has been mass-produced as a powder and crystal s ...

, silicon oxycarbide,

silicon nitride Silicon nitride is a chemical compound of the elements silicon and nitrogen. is the most thermodynamically stable and commercially important of the silicon nitrides, and the term "silicon nitride" commonly refers to this specific composition. It ...

and silicon oxynitride. Such PDCs are most commonly amorphous, lacking long-range crystalline order. Kizhakke Veettil et al

A versatile stereolithographic approach assisted by thiol-ene click chemistry, ''Additive Manufacturing 2019, volume 27 pages 80-90'' The field of preceramic polymers and polymer derived ceramics in general emerged from the requirements in aerospace industries for heat shield materials such as fiber reinforced ceramic / ceramic composite materials. The use of preceramic polymers allows for diverse processing techniques relative to conventional ceramic processing. For example, the spinning of fibres, casting of thin films and the molding of complex shapes. Commonly used preceramic polymers include polycarbosilanes and polysiloxanes, which transform through

to SiC and SiOC type ceramics respectively. {{Cite web, title=Ceramic Forming Polymers, url=https://www.starfiresystems.com/ceramic-forming-polymers/, access-date=2021-08-18, website=Starfire Systems, language=en-US Through photopolymerization methods, preceramic polymers can be used in stereolithography approaches, enabling the

additive manufacturing 3D printing or additive manufacturing is the construction of a three-dimensional object from a CAD model or a digital 3D model. It can be done in a variety of processes in which material is deposited, joined or solidified under computer co ...

of complex shaped ceramic objects. In such methods, by means of irradiation-driven cross-linking, liquid preceramic polymers transform into rigid thermoset polymers that preserve their shape through the following polymer-to-ceramic transformation that takes place in pyrolysis. In this transformation, polymers transform into glassy ceramic products.

References

Polymers Ceramics