Polyurethane-1  is an inorganic chemical compound, a segmented block copolymer derived from urethane and synthesised from isocyanates. Significant substances used in the production method: isophthalic acid, adipic acid, hexylene glycol, neopentyl glycol, dimethylolpropanoic acid and isophorone diisocyanate

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.
• "-1" 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.

• Isophthalic acid. Acid component used to provide the baseline structure of the polymer.
• Adipic acid. Another acid component contributing to the flexibility and break resistance of the polymer.
• Hexylene glycol. Alcohol monomer used to extend the chain of the polymer and enhance its resilience.
• Neopentyl glycol. Acts as a chain extender component to improve the thermal properties of the polymer.
• Dimethylolpropanoic acid (DMPA). Acts as a crosslinking agent and provides hydrophilic functional sites to the polymer.
• Isophorone Diisocyanate. Crosslinking agent providing the necessary reactivity for urethane polymer formation.

Step-by-step summary of industrial chemical synthesis process.

• The acids (isophthalic and adipic) are reacted with the glycols (hexylene and neopentyl) to form a polyester prepolymer.
• Dimethylolpropanoic acid (DMPA) is then added as a hydrophilic component and crosslinking agent.
• Isophorone Diisocyanate is introduced, and the reaction proceeds to form the urethane polymer.
• The end result is Polyurethane-1.

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.

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.

Hair fixative. This ingredient has the ability to create, with its protective film, stiffness and hold in the hair, and also has the ability to form, with its hydrophilic and elastic properties, bonds between the hair fibres, to keep the hair in a particular shape for a certain time.

Si presenta sotto forma di polvere bianca o liquido incolore.

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.