Polyurethane-99 is an inorganic chemical compound, a segmented block copolymer derived from urethane and synthesised from isocyanates.
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.
- "-99" 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.
Significant substances used in the production method:
Succinic Acid, 1,4-Butanediol, Neopentyl Glyco, Saturated Methylene Diphenyl Diisocyanate, sodium salt of 2-((2-aminoethyl)amino ethanesulfonic acid, Ethylenediamine.
Description of the raw materials used in production and their functions.
- Succinic Acid. A dicarboxylic acid used as a polyol component for polyurethane preparation, providing functional groups that react with diisocyanates.
- 1,4-Butanediol. A diol used as a chain extender and to provide soft segments to the polyurethane, enhancing flexibility.
- Neopentyl Glycol. A heat-stable diol used to improve the thermal resistance of the polyurethane.
- Saturated Methylene Diphenyl Diisocyanate. An aromatic diisocyanate used as a cross-linking agent to form the polyurethane backbone through isocyanate reactions.
- Sodium salt of 2-((2-aminoethyl)amino)ethanesulfonic acid. Used as a catalyst or modifier to influence the kinetics of polyurethane formation.
- Ethylenediamine. A diamine used as a curing agent or chain extender in the polyurethane formation process.
Step-by-step industrial synthesis.
- Preparation. Succinic Acid, 1,4-Butanediol, and Neopentyl Glycol are mixed to create a polyol base.
- Reaction. Saturated Methylene Diphenyl Diisocyanate is added, initiating the formation of polyurethane prepolymers.
- Modification. The sodium salt of 2-((2-aminoethyl)amino)ethanesulfonic acid is introduced as a catalyst.
- Chain Extension. Ethylenediamine is added to extend the polymer chains and further cure the polyurethane.
- Curing. The mixture is left to cure to ensure complete reaction and obtain the desired polyurethane.
What it is used for and where
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.
