Group Q - Thermoplastic polymers, elastomers and additives

Polysiloxane "serious is the real name of the silicones, but when they were discovered it was thought that they only had the" silicon "atoms in the skeleton of the chain, from which they took their name.When the real structure was discovered it was too late and the name remained: the silicones are inorganic polymers without carbon atoms in the main chain, their skeleton is a chain of silicon atoms that alternate with oxygen atoms, each silicon atom has two groups attached, and can be organic. they are composed mainly of methyl, vinyl and phenyl groups.

Perfect behavior at high and low temperatures: the main peculiarity of silicone is to maintain a good elasticity throughout the range of temperature of use (even at extremely low temperatures). The characteristics of purity and non-toxicity make it especially suitable for applications in the food and biomedical sector. Silicone is also the only flexible insulating material that together with excellent heat resistance, good at high flame resistance, and has a high resistance to radiation (gamma and UV rays).

Excellent resistance to oxidation, ozone and atmospheric agents. Good resistance to water and water. Dilute salt solutions, with hot water up to 100 ° C and for short periods with steam up to 120 ° C. Compatible with diluted acids and bases, aliphatic oils, motor oils, animal and vegetable oils, transformer oils, Brake fluids based of glycols and hydraulic fluids HFD-R and HFD-S, aromatic and chlorinated solvents is not compatible with mineral and silicone oils and fats, aromatic hydrocarbons, polar solvents and concentrated alkali acids.

Low gas impermeability, with hardness 10 ÷ 90 Sh. Working temperature -60 +200 ° C (also +270 ° C with peaks of more than 300 ° C for the VMQ, up to -110 ° C for the PVMQ). Glass transition temperature -120 ° C.

Silicones allow good elastomers to be obtained because their main chain is very flexible, the bonds between a silicon atom and the two oxygen bonded to it are very flexible: the angle formed by these loops can be easily opened and closed like a scissors that makes that the chain is flexible. depending on the requirements, highly electro-conductive and highly insulating compounds can be used.

Good at high flame resistance.