There are two ways of manufacturing PVP from vinylpyrrolidone. The more common method involves polymerization in water and hydrogen peroxide as the initiator; the other makes use of polymerization in an organic solvent, such as isopropyl alcohol, with organic peroxides as initiators.

Both methods yield polymers in, solution form. In the isopropyl alcohol method, the alcoholic solution is subsequently converted to an aqueous solution by steaming. Since the pharmaceuticals industry prefers powders, the aqueous solution is then dried. Low or medium molecular weight polymers are spray dried but high-molecular weight polymers are only roller-dried.

Whereas spray drying yields powders with good flow properties, roll-drying affords flakes, which are converted into smaller particles at a later stage.

PVP K-30   USP/BP/ EP
Property	Specifications	Analysis
1. Appearance at 25 C	White to creamy white powder	Passes
2. Reaction with Potassium dichromate	Positive	Passes
3. Reaction with Cobalt nitrate and Ammonium thiocyanate	Positive	Passes
4. Reaction with iodine	Positive	Passes
5. Moisture	5% max	0.16%
6. pH	3.0-7.0	3.21
7. Residue on ignition	0.1% max.	0.04%
8. Vinyl pyrrolidone	10 ppm max.	1.31 ppm
9. K-value	27-34	33.02
10. Hydrazine	< 1 ppm	< 1 ppm
11. Nitrogen	11.5% - 12.8%	11.88%
12. Heavy metals	10 ppm max.	<10 ppm
13. Aldehydes ( Calculated as Acetaldehyde )	500 ppm max.	330 ppm