Polyurethane-93 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.
- "-93" 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 Glycol, Isophorone Diisocyanate, sodium N-(2-aminoethyl)-2-aminoethanesulfonate, Isophorone Diamine.
Description of the raw materials used in production and their functions:
- Succinic Acid. Used as an acid component to form esters and impart specific properties to the polymer.
- 1,4-Butanediol. A diol used as a primary building block in the formation of polyurethane, providing flexibility to the polymer.
- Neopentyl Glycol. Diol used to enhance the thermal and chemical stability of the polyurethane.
- Isophorone Diisocyanate. Reactive component that forms urethane linkages in the polymer.
- Sodium N-(2-aminoethyl)-2-aminoethanesulfonate. A salt that can act as a catalyst or modulator in the reaction.
- Isophorone Diamine. Acts as a cross-linking agent in the formation of polyurethane.
Step-by-step industrial synthesis:
- Succinic Acid, 1,4-Butanediol, and Neopentyl Glycol are mixed in a reactor to form a polyol base.
- Isophorone Diisocyanate is added to the polyol mixture, initiating the formation of polyurethane.
- Sodium N-(2-aminoethyl)-2-aminoethanesulfonate is introduced as a catalyst or modulator in the reaction.
- Isophorone Diamine is added to facilitate cross-linking and form a more resilient polymer.
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.
Hair conditioning agent. A large number of ingredients with specific purposes can co-exist in a hair shampoo: cleansers, conditioners, thickeners, mattifying agents, sequestering agents, fragrances, preservatives, special additives. However, the indispensable ingredients are the cleansers and conditioners as they are necessary and sufficient for hair cleansing and manageability. The others act as commercial and non-essential auxiliaries such as: appearance, fragrance, colouring, etc. Hair conditioning agents have the task of increasing shine, manageability and volume, and reducing static electricity, especially after treatments such as colouring, ironing, waving, drying and brushing. They are, in practice, dispersing agents that may contain cationic surfactants, thickeners, emollients, polymers. The typology of hair conditioners includes: intensive conditioners, instant conditioners, thickening conditioners, drying conditioners.
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.
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.
