Table 2.

The most important features of siloxanes used in medicinal products, medical devices and cosmetics.

No.	Siloxanes properties
	General	Conditioning medical and cosmetic application	Conditioning medical application on skin (elastomers)
1	Low toxicity	No effect on the immune system	Biocompatibility
2	Stability-resistance to temperature (-100 to 250°C)	No carcinogenic effect	Highly non-toxic
3	Stability-resistance to atmospheric condition	Do not irritate skin or have low irritation	Ability to adhesion
4	Stability-aging resistance	Do not foster the growth of microorganisms	Anti-adhesion
5	Stability-resistance to oxidation	Safety of application due to the lack of penetration through cell membranes	Ability to permeation of water vapor and oxygen
6	Stability-resistance to moisture	Similar to hydrophilic/lipophilic properties of human skin	Ability to skin occlusion
7	Stability-resistance to UV radiation	Lack of reactivity with respect to the active pharmaceutical ingredient and excipients	Hydration of stratum corneum
8	Resistance to degradation	Similarity to biological membranes	Possibility of the diffusion of the active substance
9	Low chemical reactivity	Clearness, colorless, odorless	Transparency
10	Low surface energy	Easy spreading	Non-visible on the skin
11	Low surface tension	Low heat of vaporization	Resistance to extensibility and deformation
12	Smooth texture	Compatible with a wide range of solvents	Flexibility
13	Hydrophobicity	Imparts a soft-silky feel to the skin
14	Water repellent
15	Hydrophilicity