Povidone is a linear polymer of 1-vinyl-2-pyrrolidinone monomer with different degrees of polymerization, which results in polymers of a wide range of molecular weights (2,500–3,000,000 Da), usually expressed as K value (K30, K60, K85, K90, K120), Povidone is white or yellowish-white, hygroscopic powder or flakes, freely soluble in water, in ethanol (95 per cent) and in chloroform, practically insoluble in ethercan be used in many industries. Nowadays, Povidone can be used in a variety of different fields, like Pharma, Cosmetics, Food, Watertreatment, Solid gule, Oral Care.
Povidone is a water-soluble polymer product based on N-vinyl pyrrolidone. Due to its unique properties, it has been widely used in various fields. The current global application volume of PVP in various fields, as well as its functions and advantages are shown in the following graph:
Usage | Advantages | Representative drugs |
Tablet Binder | Hard, good fluidity, no dust, strong adhesion, reduced fragility, and reduced peeling | Vitamin D, paracetamol, ibuprofen granules |
Solub ilization | Solub ilizers, d ispersants, crystallization inhibitors, stabilizers for antibiotic suspensions | Acetaminophen (paracetamol), allopurinol, reserpine |
Co-precipitation and grinding | The active ingredients of drugs that are poorly soluble in water can form powder or co-precipitate with PVPK series and dissolve very quickly, thereby improving biological effectiveness. | Nitropyridine, trimethoprim, reserpine |
Hydrophilic agent, lubricant | Since PVP is hydrophilic and has a lubricating effect, it can also be used as artificial tears (the amount added is (2-10%) | Eye drops, artificial tears, contact lens solution |
Usage | Advantages | Representative Product |
Have Strong Styling Effect | When K90 is used alone, a concentration of 3% can achieve a strong styling effect | Hair styling products |
Lubrication Moisturizer | Lubricate, moisturize, and form films (masks) in emulsions and sunscreens | Skin care products |
Complexing ability and dispersing ability | Increase the decontamination ability of toothpaste | Toothpaste |
Usage | Advantages | Representative industry |
Pore-Forming Agent | Control the membrane pore size and pore distribution, increase the density of membrane pores | Membrane Materials |
Natural Gas Hydration Inhibitor | Efficient natural gas hydration inhibitor, adding 1-2% of K90 can inhibit the formation of hydrate within nearly 20 hours. | Natural Gas Extraction |
Binder | Strong bonding ability, good initial adhesion, good coating performance, thin and uniform coating | Solid Glue Sticks |
Adhesion For Glass | Polishing agent for glass fiber to make the surface smoother, also can reduce wear during stretching, and increase fiber bundle cohesion. | Glass fiber |
Film-forming and hygroscopic properties of Polyvidone
PVP can be cast or coated into a film from a solution of water, methanol, ethanol, chloroform or dichloroethane. The PVP film is colorless, transparent, hard and bright. The solvent has no effect on the resulting film. PVP has strong hygroscopicity. When the PVP film absorbs moisture from air with a relative humidity of 70%, it will have a certain degree of viscosity.
Complexation of Polyvidone
PVP is a polymer with high "solubility". This "solubility" ability is due to the fact that its molecular structure has advanced properties and amide groups that can accept hydrogen chains, as well as non-polar genes. Both groups have the ability to "dissolve" the corresponding groups on small molecular components. This ability enables PVP to react with many substances, especially polymers with static "solubility". This "solubility" ability is due to the fact that its molecular structure has advanced properties and amide groups that can accept hydrogen chains, as well as non-polar genes. Both groups have the ability to "dissolve" the corresponding groups on small molecular components. This ability enables PVP to produce solid complexes with many substances, especially compounds containing hydroxyl, carboxyl, amino and other active hydrogen atoms.
Biological characteristics of polyvidone
PVP has excellent physiological inertness and does not participate in human metabolism. It also has excellent biocompatibility and does not cause any irritation to the skin, mucous membranes, eyes, etc., so that PVP is widely used as an excipient for pharmaceutical preparations and was even used as a plasma substitute during the war, saving many lives.
Safety of Polyvidone
PVP has excellent physiological inertness and biocompatibility, so it is widely used in food, cosmetics, and pharmaceutical industries. In the pharmaceutical industry, it is mainly used as an auxiliary material. For all application methods, its acute toxicity is low, and long-term use at normal doses does not cause significant tissue damage. It is not antigenic to the human body and does not inhibit the production of antibodies. The human body can be accepted through the digestive tract, subabdominal, subcutaneous and intravenous routes, and no carcinogenic effect on humans has been found.
PVP can be used as a dispersant for lithium battery cathode materials,In the field of new energy batteries, the amount of PVP used is about 15 tons for 1GWh, mainly using industrial grade PVP K30 and PVP K90,Due to the rise of new energy vehicles, the global annual demand for PVP for lithium batteries is expected to reach 33,100 tons in 2025.
Hollow fiber membrane material is the core technology of kidney dialysis membrane. As a porogen, PVP has stable chemical properties and can effectively control the size and distribution of membrane pores; increase the density of membrane pores, improve the permeability of the
membrane; and improve the surface of the membrane. Hydrophilic and good biocompatibility, our company won the bid for the national project "Polymer PVP materials for kidney dialysis".
In terms of natural gas extraction, PVP, as the preferred natural gas hydrate inhibitor, plays a very important role in reducing the formation of crystallization and blockage in natural gas pipelines.
N-vinyl pyrrolidone (NVP) can be homopolymerized, copolymerized or grafted with many vinyl monomers to generate various homopolymers and copolymers, each with different properties and uses, and each with its own characteristics. PVP is its homopolymerized product, with a molecular weight ranging from 1000-1000000, and can form a series of products with different specifications to meet different application requirements. The main methods are as follows:
Bulk polymerization
NVP can be thermally initiated polymerization at 140°C and higher. When NVP and peroxide are heated to 110 degrees Celsius, polymerization occurs quickly, and the reaction temperature rises to 110-190°C by itself, generating a molten polymer. After cooling, it is crushed to form a hygroscopic polymer powder. However, the polymer obtained by this method has the disadvantages of yellow color, low K value, and high residual monomer content due to the increase in viscosity during the polymerization process, the diffusion of the polymer, and local overheating, so it is rarely used in industry.
Solution polymerization
PVP obtained by bulk polymerization must be purified, otherwise it cannot meet the requirements of commercial products. Therefore, solution polymerization of NVP was developed. NVP can be polymerized in many solvents, such as isopropanol, methanol, ethyl acetate, benzene, water and other solvents. Since water is the cheapest and safest solvent, aqueous solution polymerization is generally used more. NVP can be polymerized in aqueous solution using peroxide alone as an initiator and ammonium or amine as an activator. This system is generally used to prepare PVP with lower molecular weight, such as K30. To prepare high molecular weight PVP, azo initiators can also be used.
Suspension polymerization
Add a dispersant called Gentexv-516 to heptane, disperse NVP and a small amount of water together into oil drops, suspend them in heptane, and then use AIBN to initiate polymerization at 25°C to obtain PVP with an average molecular weight of up to 670,000.