Inorganic polymer

Inorganic polymers are polymers with a skeletal structure that does not include carbon atoms^[1]. Polymers containing inorganic and organic components are named hybrid polymers^[2]. One of the best known examples is polydimethylsiloxane, otherwise known commonly as silicone rubber. It has a repeat unit based on silicon and oxygen:

—[O-Si(CH₃)₂]_n—

Silicon and oxygen also occur widely in a range of inorganic minerals, including silica, mica and feldspar with other elements.

The inorganic sulfur-nitrogen polymer polythiazyl, (SN)_x, is, highly unusually, a metallic superconducting polymer below 0.26 K.^[3]

Examples

• Homochain polymers with one kind of atom in the main chain:
  • Silicon-Silicon: Polysilanes;
  • Germanium-germanium: Polygermanes;
  • Tin-tin: Polystannanes.

• Heterochain polymers with more than one type of atom in the main chain, mostly two types of atoms alternate along the main chain:
  • Boron-nitrogen: Polyborazylenes;
  • Silicon-Oxygen: Polysiloxanes like the Polydimethylsiloxane (PDMS), Polymethylhydrosiloxane (PMHS) and polydiphenylsiloxane;
  • Silicon-nitrogen: Polysilazanes like Perhydridopolysilazane PHPS
  • Phosphorus-nitrogen: Polyphosphazenes and their precursor the Poly(dichlorophosphazene);
  • Sulfur-nitrogen: Polythiazyls.

• Sulfur: Polysulfides.

Polymerization

Inorganic polymers are formed, like organic polymers, by:

• Step-growth polymerization: Polysiloxanes;
• Chain-growth polymerization: Polysilanes;
• Ring-opening polymerization: Poly(dichlorophosphazene).

References

External links

• Polymer Structure