Polyurethane-72 is an inorganic chemical compound, a segmented block copolymer derived from urethane and obtained by the synthesis process  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.
• "-72" 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:

Hydrogenated Acetophenone/Oxymethylene Copolymer, Isophorone Diisocyanate (IPDI), dimethylolpropanoic acid, Dimethyl MEA, water.

Description of the raw materials used in production and their functions:

• Hydrogenated Acetophenone/Oxymethylene Copolymer. Serves as the polyol base for the formation of polyurethane and determines the main properties of the polymer.
• Isophorone Diisocyanate (IPDI). Reactive component that forms urethane linkages in the polymer.
• Dimethylolpropanoic Acid. Provides hydroxyl functional groups that react with diisocyanates to form the polyurethane.
• Dimethyl MEA. Acts as a catalyst in the reaction.
• Water. Used to adjust viscosity and aid in the mixing of components.

Step-by-step industrial synthesis:

• The Hydrogenated Acetophenone/Oxymethylene Copolymer is mixed with dimethylolpropanoic acid in a reactor to prepare the polyol base.
• Isophorone Diisocyanate is added to the polyol mixture, initiating the formation of polyurethane.
• Dimethyl MEA is introduced as a catalyst to speed up the reaction between the polyols and the diisocyanate.
• Water is slowly added to reach the desired viscosity and ensure homogeneous mixing of the components.

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.

Nail Conditioning agent. It is an agent that creates protection against harmful or chemical substances by strengthening the nail structure against external elements and can repair any chipping, cracking or brittle nails. It helps keep the nail's outer layer and keratin protein in good condition. It can also prevent cracking and peeling of the nail.

CAS: 502761-95-7

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.