Polyurethane-36 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.
- "-36" 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:
PPG-17, isophorone diisocyanate (IPDI), dimethylol propionic acid, water, triethylamine, hydrazine.
Description of raw materials used in production with their functions.
- PPG-17. Polypropylene glycol. A polyol used as a primary component in forming polyurethanes. Provides flexibility to the final product.
- Isophorone diisocyanate (IPDI). A diisocyanate used to react with polyols to form urethane linkages.
- Dimethylol propionic acid. An acid with two alcohol functional groups, which is used as a stabilizer for aqueous dispersions and provides reactive sites for urethane bond formation.
- Water. Acts as a dispersion agent and can also react with IPDI to form urea bonds.
- Triethylamine. Used to neutralize the dimethylol propionic acid, enabling stable aqueous dispersions to form.
- Hydrazine. A chain extender agent used to help form the polymer.
Step-by-step summary of industrial chemical synthesis process.
- PPG-17 is reacted with IPDI to form a prepolymer.
- Dimethylol propionic acid is added and reacted to form reactive sites in the prepolymer.
- Triethylamine is added to neutralize the acid groups, forming a dispersion.
- Water is added to form an aqueous dispersion of the prepolymer.
- Hydrazine is finally added as a chain-extending agent to form the final 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.
