Polyvinylpyrrolidone (PVP K-30)

Polyvinylpyrrolidone (PVP, also called povidone) is a synthetic polymer made from the monomer N-vinylpyrrolidone. The "K-30" is its K-value, a number based on solution viscosity that indicates the chain length. K-30 is a mid-range grade, the one most often used in cosmetics and tablets.

• Formula: (C6H9NO)n
• CAS number: 9003-39-8
• Molecular weight: a range rather than one figure; K-30 is a medium grade in the tens of thousands g/mol
• Appearance: white to off-white, free-flowing powder
• Solubility: dissolves readily in water and in alcohols such as ethanol

It's hygroscopic, so it picks up moisture from the air and can cake if left open. As a solution dries, it leaves a clear, slightly stiff film.

Azlok lists Polyvinyl Pyrrolidone (PVP K-30) as a cosmetic raw ingredient. The listing name doesn't give a pack size, so check the product page. Higher K-values (K-60, K-90) give thicker solutions and stiffer films; lower ones give thinner solutions. See today's price per kg.

• Hair styling: the film former in hair gels, styling sprays and mousses that hold hair in place.
• Cosmetics: a film former and dispersant in makeup, mascara and some creams.
• Pharma and nutraceuticals: a binder that holds tablet granules together, made to pharmacopoeia grade.
• Industry: adhesives and glue sticks, inks, paper and textile coatings, and in laundry detergents to help keep dyes from transferring.

• Dissolving: sprinkle the powder slowly into the vortex of stirred water at room temperature. Adding it all at once makes sticky lumps that take hours to dissolve.
• Hair gel: PVP is typically used at a few percent, around 2 to 5%, usually with a thickener such as carbomer to give the gel body. More PVP means firmer hold but more flaking.
• Alcohol-based sprays: it also dissolves in ethanol, so it can be used in quick-drying styling sprays.
• Humidity: PVP films soften in humid weather. Formulators often add a little glycerine or a plasticiser to cut flaking.

These are typical ranges. Patch test any finished product on the inner arm for 24 hours before regular use. Finished cosmetics sold in India also need to meet the applicable BIS and CDSCO rules.

• The fine powder can irritate the eyes and throat. Weigh it gently and wear a dust mask for large amounts.
• Spilled powder becomes very slippery when wet. Sweep it up dry first.
• Store in a tightly closed container in a cool, dry place. Damp storage makes it cake into hard lumps.
• Keep away from strong oxidisers.
• Keep out of reach of children. Small amounts can go in normal waste.

For hair gel recipes and small trials, a small pack lasts a while since you use only a few percent. Gel and styling product makers producing every week should buy at least 1 kg. Tablet makers need pharmacopoeia grade with full documentation, so mention that when you ask. For 25 kg or more, use the bulk inquiry form.