Polyurethane-2 is an inorganic chemical compound, a segmented block copolymer derived from urethane and synthesised from isocyanates.
Significant substances used in the production method:
hexylene glycol, neopentyl glycol, adipic acid, saturated methylene diphenyldiisocyanate, dimethylolpropanoic acid.
The name describes the structure of the molecule:
- "Polyurethane" is a term that describes a class of polymers widely used in various applications due to their versatility and desirable properties such as durability, flexibility and abrasion resistance and temperature variations.
- "-2" is a reference to the specific type or grade of polyurethane, which can be characterized by such factors as the types of isocyanates and polyols used, their relative amounts, and the presence of any additives. . This is a designation used to differentiate different molecular structures or variants of the polymer. In cosmetic chemistry, these numbers can help formulators identify specific characteristics or behaviors of a given ingredient, particularly when a chemical family has multiple derivatives or forms.
Description of raw materials used in production and their functions.
- Hexylene glycol. A polyol that provides hydroxyl groups for the formation of polyurethane.
- Neopentyl glycol. Another polyol used in the formation of polyurethane.
- Adipic acid. Provides carboxylic groups and increases the polymer's flexibility.
- Saturated methylene diphenyldiisocyanate. Provides isocyanate groups for the formation of polyurethane.
- Dimethylolpropanoic acid. Adds hydroxyl and carboxylic groups to the polymer.
Step-by-step summary of industrial chemical synthesis process.
- Hexylene glycol, neopentyl glycol, adipic acid, and dimethylolpropanoic acid are reacted with saturated methylene diphenyldiisocyanate to form the polyurethane.
- This reaction forms a cross-linked polymer structure, stabilizing and completing the polyurethane formation.
What it is used for and where
Polyurethanes can be used in a wide range of applications due to their versatility. They can be flexible or rigid and are used in products such as foams, coatings, adhesives, sealants and elastomers.
Cosmetics
Film-forming agent. It produces a continuous ultra-thin film with an optimal balance of cohesion, adhesion and stickiness on the skin or hair to counteract or limit damage from external phenomena such as chemicals, UV rays and pollution.
It appears as a white powder or colorless liquid.
Safety
Urethane (also called ethyl carbamate) is a by-product of fermentation and is considered a genotoxic agent.
Polyurethanes are rather complex, inert and biostable materials that are also used in biomedical applications. They are typically synthesised by the reaction of a glycol or polyol with polyisocyanate or diisocyanate. It is known that exposure to isocyanates can cause asthma, contact allergies, conjunctival and skin irritation. However, a study by the Cosmetic Ingredient Review Expert Panel in 2017 found that the rates of harmful residues are not significant for human health.
