Polyurethane-74 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.
- "-74" 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:
Isophorone Diisocyanate, neopenyl glycol mono(hydroxypivalate), diethyl carbonate, Hexanediol, Glycol, epsilon-caprolactone, 2-hydroxyethyl acrylate.
Description of raw materials used in production and their functions.
- Isophorone Diisocyanate. A diisocyanate that reacts with polyols to form the urethane linkage.
- Neopenyl glycol mono(hydroxypivalate). Serves as a polyol, providing flexibility and structure to the polyurethane.
- Diethyl carbonate. A solvent and reagent in polyurethane production.
- Hexanediol and Glycol. Other polyols that help modulate the properties of the polyurethane.
- Epsilon-caprolactone. A monomer that can be used to extend chains and modify polymer properties.
- 2-hydroxyethyl acrylate. Provides additional functionality and improves reactivity with other compounds during synthesis.
Step-by-step summary of industrial chemical synthesis process.
- Preparation. Neopenyl glycol mono(hydroxypivalate), Hexanediol, Glycol, and epsilon-caprolactone are introduced into a reactor and heated to a specified temperature.
- Addition. Isophorone Diisocyanate is slowly added to the reactor while stirring.
- Reaction. The urethane linkage forms between the polyols and the diisocyanate.
- Incorporation of 2-hydroxyethyl acrylate. 2-hydroxyethyl acrylate is added to enhance the properties of the polyurethane.
- Purification. Any unreacted components are removed, and the polyurethane is purified.
- Finalization. The resulting polyurethane is cooled and prepared for end applications.
What it is used for and where
Cosmetics
Binder agent. Ingredient that is used in cosmetic, food and pharmaceutical products as an anti-caking agent with the function of making the product in which it is incorporated silky, compact and homogenous. The binder, either natural such as mucilage, gums and starches or chemical, may be in the form of a powder or liquid.
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.
