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Polyvinylpyrrolidone
Polyvinylpyrrolidone
Polyvinylpyrrolidone
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Polyvinylpyrrolidone
150pxc
150pxc
Names
IUPAC name
1-Ethenylpyrrolidin-2-one
Other names
PVP, PNVP, povidone, polyvidone, kollidon
Poly[1-(2-oxo-1-pyrrolidinyl)ethylen]
1-Ethenyl-2-pyrrolidon homopolymer
1-Vinyl-2-pyrrolidinon-polymere
Poly-N-vinylpyrrolidine
Identifiers
3D model (JSmol)
Abbreviations PVP, NVP, PNVP
ChEMBL
ChemSpider
  • none
ECHA InfoCard 100.111.937 Edit this at Wikidata
E number E1201 (additional chemicals)
UNII
  • N1(C(CCC1)=O)[C@@H](C*)*
Properties
(C6H9NO)n
Molar mass 2,500–2,500,000 g·mol−1
Appearance white to light yellow, hygroscopic, amorphous powder
Density 1.2 g/cm3
Melting point 150 to 180 °C (302 to 356 °F; 423 to 453 K) (glass temperature)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Polyvinylpyrrolidone (PVP), also commonly called povidone, is a water-soluble polymer compound made from the monomer N-vinylpyrrolidone.[1] PVP is available in a range of molecular weights and related viscosities, and can be selected according to the desired application properties.[2]

Uses

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Medical

[edit]
Structure of povidone-iodine complex, a common antiseptic[3]

There are high-purity injectable grades of PVP available on the market, for specific use in intravenous, intramuscular, and subcutaneous applications.[4]

PVP is a frequently used binder in pharmaceutical tablet formulations.[5] Pharmacokinetic studies in humans and various laboratory animal models indicate no to very little systemic absorption of PVP following oral administration.[6]

PVP added to iodine forms a complex called povidone-iodine that possesses disinfectant properties.[7] This complex is used in various products such as solutions, ointment, pessaries, liquid soaps, and surgical scrubs. It is sold under the trade names Pyodine and Betadine, among others.

It is used in pleurodesis (fusion of the pleura because of incessant pleural effusions). For this purpose, povidone-iodine is as effective and safe as talc, and may be preferred because of its easy availability and low cost.[8]

PVP is used in some contact lenses and their packaging solutions. It reduces friction, thus acting as a lubricant, or wetting agent, built into the lens. Examples of this use include Bausch & Lomb's Ultra contact lenses with MoistureSeal Technology,[9] Air Optix contact lens packaging solution (as an ingredient called "copolymer 845"),[10] and Johnson & Johnson's Acuvue contact lenses.[11]

PVP is used as a lubricant in some eye drops, e.g. Bausch & Lomb's Soothe.[12]

PVP was used as a plasma volume expander for trauma victims after the 1950s. It is not preferred as a volume expander due to its ability to provoke histamine release and also interfere with blood grouping.[citation needed]

Technical

[edit]

PVP is also used in many technical applications:

Other uses

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PVP binds to polar molecules exceptionally well, owing to its polarity. This has led to its application in coatings for photo-quality ink-jet papers and transparencies, as well as in inks for inkjet printers.

PVP is also used in personal care products, such as shampoos and toothpastes, in paints, and adhesives that must be moistened, such as old-style postage stamps and envelopes. It has also been used in contact lens solutions and in steel-quenching solutions.[19][20] PVP is the basis of the early formulas for hair sprays and hair gels, and still continues to be a component of some.

As a food additive, PVP is a stabilizer and has E number E1201. PVPP (crospovidone) is E1202. It is also used in the wine industry as a fining agent for white wine and some beers.

In in-vitro fertilisation laboratories, polyvinylpyrrolidone is used to slow down spermatozoa in order to capture them for e.g. ICSI.

In molecular biology, PVP can be used as a blocking agent during Southern blot analysis as a component of Denhardt's buffer. It is also exceptionally good at absorbing polyphenols during DNA purification. Polyphenols are common in many plant tissues and can deactivate proteins if not removed and therefore inhibit many downstream reactions like PCR.

In microscopy, PVP is useful for making an aqueous mounting medium.[21]

PVP can be used to screen for phenolic properties, as referenced in a 2000 study on the effect of plant extracts on insulin production.[22]

Safety

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The U.S. Food and Drug Administration (FDA) has approved this chemical for many uses,[23] and it is generally recognized as safe (GRAS). PVP is included in the Inactive Ingredient Database for use in oral, topical, and injectable formulations.

However, there have been documented cases of allergic reactions to PVP/povidone, particularly regarding subcutaneous (applied under the skin) use and situations where the PVP has come in contact with autologous serum (internal blood fluids) and mucous membranes.

Examples of documented allergic reactions:

Additionally, Povidone is commonly used in conjunction with other chemicals. Some of these, such as iodine and penicillin[27], for example, are blamed for allergic responses. Yet subsequent testing results in some patients show no signs of allergy to the suspect chemical. Allergies attributed to these other chemicals may possibly be caused by the PVP instead.[28][29]

Properties

[edit]

PVP is soluble in water and other polar solvents. For example, it is soluble in various alcohols, such as methanol and ethanol,[30] as well as in more exotic solvents like the deep eutectic solvent formed by choline chloride and urea (Relin).[31] When dry it is a light flaky hygroscopic powder, readily absorbing up to 40% of its weight in atmospheric water. In solution, it has excellent wetting properties and readily forms films. This makes it good as a coating or an additive to coatings.

A 2014 study found fluorescent properties of PVP and its oxidized hydrolyzate.[32]

History

[edit]

Povidone was first synthesized by BASF chemist Walter Reppe, and a patent was filed in 1939 for one of the derivatives of acetylene chemistry. PVP was initially used as a blood plasma substitute and later in a wide variety of applications in medicine, pharmacy, cosmetics and industrial production.[33][34] BASF continues to make PVP, including a pharmaceutical portfolio under the brand name of Kollidon.[35]

Cross-linked derivatives

[edit]
Main article: Polyvinylpolypyrrolidone

See also

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References

[edit]
Revisions and contributorsEdit on WikipediaRead on Wikipedia

Polyvinylpyrrolidone

View on Grokipedia
from Grokipedia
Polyvinylpyrrolidone (PVP), also known as povidone or polyvidone, is a synthetic, water-soluble consisting of repeating units of 1-vinyl-2-pyrrolidone, with the (C₆H₉NO)ₙ and a molecular weight ranging from 2,500 to 3,000,000 Da. It is characterized by its high solubility in water and many organic solvents, , non-toxicity, chemical inertness, stability, and hygroscopic nature, making it a versatile material for diverse industrial and biomedical applications. Discovered in 1938 by Walter Reppe at through acetylene-based chemistry and patented in 1939, PVP was initially developed via the Reppe process and later produced through free radical polymerization of N-vinylpyrrolidone monomer in bulk, solution, or suspension methods. During , it served as a plasma due to its ability to mimic colloidal properties of , though this use was discontinued post-war due to concerns about its accumulation and storage in internal organs. In pharmaceuticals, PVP functions primarily as an , acting as a binder in tablets, a solubilizer and stabilizer in solid dispersions for poorly soluble drugs, a film-former in coatings, and a carrier in controlled-release systems such as nanoparticles and hydrogels. It is also a key component in (PVP-I), an complex that slowly releases iodine for effects, including potential applications in inhibiting viral infections like COVID-19. Beyond , PVP finds uses in as a hair fixative and film-former, in textiles for stripping, in for its film-forming and adhesive properties, and in as a . Its tunable properties, such as the K-value (10–120) indicating and molecular weight, allow customization for specific formulations.

Chemical Structure and Synthesis

Monomer Composition

N-Vinylpyrrolidone (NVP), the primary monomer used in the synthesis of polyvinylpyrrolidone, has the molecular formula C₆H₉NO and a of 111.14 g/mol. Its structure features a five-membered ring derived from 2-pyrrolidone, with a (–CH=CH₂) attached to the nitrogen atom at the 1-position, enabling its role as a reactive olefin in processes. NVP is a colorless to pale yellow liquid at , with a of 13–14 °C and a of 217 °C at standard . It exhibits high , being fully miscible with and readily soluble in common organic solvents such as , acetone, , , and . The monomer's chemical reactivity stems from the conjugated vinyl , which is electron-rich due to with the carbonyl, making NVP highly susceptible to addition reactions, including free radical-initiated . The synthesis of N-vinylpyrrolidone was pioneered in 1939 by Walter Reppe through -based vinylation of 2-pyrrolidone under high pressure and temperature with a basic catalyst. Modern industrial production follows this Reppe process, involving the direct reaction of 2-pyrrolidone with gas, where the precursor 2-pyrrolidone is often derived from a chain starting with and to form 1,4-butynediol, followed by and cyclization steps. Impurities arising during NVP production, such as unreacted 2-pyrrolidone, water, or trace aldehydes from the route, can significantly compromise the quality of the resulting polyvinylpyrrolidone if not adequately removed through or other purification methods. These contaminants often act as polymerization retarders or agents, leading to lower molecular weights, incomplete conversions, or inconsistent properties like and . Standard purification techniques may be insufficient for complete removal, necessitating advanced analytical methods like gas chromatography-mass spectrometry for impurity profiling.

Polymerization Mechanisms

Polyvinylpyrrolidone (PVP) is primarily synthesized through free radical of N-vinylpyrrolidone (NVP) , a process that links the vinyl groups to form long polymer chains. This method dominates industrial and laboratory production due to its versatility and ability to yield polymers with molecular weights ranging from 2,500 to over 1,000,000 g/mol. The reaction typically proceeds in solution, employing thermal initiators such as (e.g., di-tertiary-butyl peroxide or ) or azo compounds (e.g., 2,2'-azobisisobutyronitrile), which decompose to generate radicals that initiate chain growth. The overall polymerization can be represented by the equation: n \ceCH2=CH−N(C4H6O)→\ce[−CH2−CH(NC4H6O)−]nn \ \ce{CH2=CH-N(C4H6O)} \rightarrow \ce{[-CH2-CH(NC4H6O)-]_n} where the repeating unit incorporates the pyrrolidone ring pendant to the backbone. Alternative polymerization mechanisms, though less common, include anionic and cationic routes, each requiring specific conditions to mitigate the reactivity of the amide group in NVP. Anionic polymerization employs strong bases like alkali metal amides or alkoxides at low temperatures (typically below 0°C) in aprotic solvents such as tetrahydrofuran, enabling better control over molecular weight distribution compared to free radical methods; however, it is challenging due to potential side reactions with the polar carbonyl. Cationic polymerization, initiated by Lewis acids like boron trifluoride, proceeds at even lower temperatures but yields only low-molecular-weight oligomers (degree of polymerization up to 100), limiting its practical utility. Several factors influence the chain length and molecular weight in free radical polymerization of NVP. Higher monomer concentrations generally promote longer chains by favoring propagation over termination, while temperatures in the range of 50–80°C optimize initiation rates without excessive chain transfer. Solvent choice is critical: polar protic media like water or alcohols (e.g., isopropanol) enhance solubility and rate constants but can introduce transfer reactions, whereas non-polar solvents like toluene may slow the process due to poorer solvation of the growing chain. The atactic nature of PVP arises predominantly from the free radical mechanism, which lacks stereocontrol, resulting in a random configuration of the chiral centers along the chain as confirmed by 13C NMR analysis showing comparable isotactic, syndiotactic, and heterotactic triad populations. End-group analysis, often via NMR or , reveals initiator-derived fragments (e.g., cyanoisopropyl from azo initiators) at one terminus and or solvent-derived groups at the other, influencing functionality such as reactivity in further modifications. In aqueous or alcoholic media, hydroxyl or carbonyl end groups may predominate due to transfer to .

Physical and Chemical Properties

Solubility and Rheological Behavior

Polyvinylpyrrolidone (PVP) is highly soluble in across a broad range of molecular weights, from low values around Da up to approximately 10^6 Da, forming clear, viscous solutions even at concentrations exceeding 270 g/L for high-molecular-weight grades like K90. in decreases modestly with increasing molecular weight due to higher solution , but remains excellent owing to the polar groups in the structure. The (δ) for PVP falls within 22-25 MPa^{1/2}, facilitating its dissolution in polar media, including , primarily through hydrogen bonding interactions despite the parameter difference from (47.9 MPa^{1/2}). In organic solvents, PVP dissolves readily in polar options such as lower alcohols (e.g., , , isopropanol) and , attributed to its amphiphilic nature from the ring. Conversely, it is insoluble in non-polar solvents like ethers, acetone, and aliphatic hydrocarbons, limiting its use in such media. The rheological behavior of PVP solutions is characterized by increasing with higher concentration and molecular weight, often exhibiting non-Newtonian (pseudoplastic) flow at elevated levels due to chain entanglement and . This is quantified using the K-value from the Fikentscher equation, which correlates with relative in and serves as a standard for grading PVP; low-molecular-weight variants typically have K-values of 15-30, while high-molecular-weight ones reach 85-120. PVP is notably hygroscopic, absorbing up to 40% of its weight in under humid conditions, which enhances its processability in aqueous formulations. This property supports its ability to form clear, flexible, and films upon of from solutions, with film strength increasing with molecular weight.

Thermal Stability and Degradation

Polyvinylpyrrolidone (PVP) has a temperature (Tg) of approximately 150–180 °C, depending on molecular weight, marking the transition from glassy to rubbery state. PVP exhibits good thermal stability up to moderate temperatures, with the onset of typically occurring between 250°C and 300°C under inert atmospheres, as determined by (TGA). This initial degradation involves chain scission and opening of the ring within the pyrrolidone side groups, leading to progressive breakdown of the polymer backbone. Full degradation is generally achieved above 400°C, where nearly complete mass loss is observed, resulting in volatile fragments and residual char in some cases. The primary degradation pathway proceeds via , yielding N-vinylpyrrolidone (C₆H₉NO) as the main volatile product, along with byproducts such as (NH₃), (CO), and (CO₂). This mechanism is supported by coupled TG-FTIR studies, which identify vinylpyrrolidone as the dominant evolved gas during heating. The simplified reaction can be represented as: [−\ceCH2−CH(NC4H6O)−]n→n\ceC6H9NO+byproducts\left[ -\ce{CH2-CH(NC4H6O)-} \right]_n \rightarrow n \ce{C6H9NO} + \text{byproducts} TGA profiles of PVP often show approximately 5% weight loss by 200°C, primarily due to residual or minor side-chain elimination, prior to the major decomposition stage. PVP demonstrates enhanced oxidative stability when formulated with antioxidants, which mitigate radical formation during exposure to air at elevated temperatures. However, the polymer is sensitive to ultraviolet (UV) radiation, which can induce photo-oxidation and result in yellowing through formation of chromophoric degradation products. This UV-induced discoloration is particularly relevant for applications requiring long-term light exposure, where stabilizers are employed to preserve optical clarity.

Manufacturing and Commercial Aspects

Industrial Production Processes

Polyvinylpyrrolidone (PVP) is industrially produced via free radical polymerization of the , a originally developed by using Reppe acetylene chemistry for monomer preparation, though the focus here is on the polymerization stage. The reaction is typically conducted in aqueous media with as the initiator, or in alcoholic solvents such as 2-propanol or for broader molecular weight control ranging from 2,500 to 1,000,000 Da. Both batch and continuous es are employed to achieve high efficiency at scale, with the continuous mode facilitating steady-state operation in large reactors. Scale-up considerations are critical for maintaining reaction uniformity, including optimized through jacketed reactors to manage the exothermic , precise initiator dosing to control reaction kinetics, and the use of agents like thiols (e.g., mercaptoethanol) to regulate molecular weight and polydispersity. These agents terminate growing chains, allowing producers to tailor PVP grades for specific applications while minimizing unwanted side reactions. Post-polymerization, the product is isolated by in non-solvents such as acetone, which effectively separates the water-soluble from the reaction mixture. Purification follows to remove unreacted monomers, initiators, and low-molecular-weight impurities, often involving or dialysis for residual elimination, particularly in pharmaceutical-grade production. The purified solution is then dried—via for low- to medium-molecular-weight grades or drying for higher ones—to yield a free-flowing powder. Major global producers include BASF SE, Holdings Inc., and Boai NKY Pharmaceuticals Ltd., with total worldwide capacity reaching approximately 82,000 tons per year as of 2023, driven largely by demand in pharmaceuticals and personal care.

Grades, Specifications, and Purity

Polyvinylpyrrolidone (PVP) is commercially available in various grades differentiated primarily by their K-value, which correlates with molecular weight and , allowing tailoring to specific applications. Pharmaceutical grades, such as PVP K30 with a molecular weight of approximately 40,000–50,000 Da and K-value range of 25–35, are commonly used in formulations due to their and binding properties. Technical grades, like PVP K90 with a molecular weight around 1,000,000 Da and K-value of 85–97, offer higher for industrial uses such as adhesives and coatings. Purity standards for PVP are stringent, particularly for pharmaceutical applications, as outlined in the United States Pharmacopeia/National Formulary (USP/NF) and (Ph. Eur.) monographs. These require ash content not exceeding 0.1% and heavy metals limited to less than 10 ppm to ensure safety and efficacy in drug products. Technical grades maintain high purity, typically above 99%, but may have slightly relaxed limits on impurities compared to pharmaceutical variants. Due to its hygroscopic nature, PVP is packaged in moisture-proof materials such as multi-layered plastic bags or fiber drums lined with to prevent absorption of atmospheric and subsequent clumping. Storage recommendations include cool, dry conditions below 25°C and relative humidity under 60% to maintain flowability and stability. Commercial pricing for PVP ranges from $5 to $15 per kg, influenced by grade purity and molecular weight, with pharmaceutical grades commanding higher costs due to rigorous testing. The global is dominated by production in , particularly and , and , with major suppliers including and Ashland facilitating distribution.

Applications

Pharmaceutical and Medical Uses

Polyvinylpyrrolidone (PVP) serves as a versatile in pharmaceutical formulations, particularly as a binder and disintegrant in oral tablets. In wet granulation processes, PVP, often in grades like K30, is incorporated at concentrations of 2-5% to enhance tablet cohesion and mechanical strength while promoting rapid disintegration upon ingestion. This dual functionality improves drug release profiles, as demonstrated in formulations of drugs such as , where PVP K30 at 4-10% w/w contributed to optimal hardness and disintegration times without compromising . Additionally, PVP acts as a solubilizer for poorly water-soluble drugs through the formation of inclusion complexes and dispersions, such as indomethacin and . A prominent medical application of PVP is in antiseptics, where it complexes with iodine at a 10% PVP to 1% available iodine ratio to form a stable, broad-spectrum agent for topical use in wound care and surgical scrubs. Historically, PVP was employed as a plasma volume expander during the 1940s, particularly in military medical contexts, but its use has been largely discontinued due to tissue retention issues, especially with high-molecular-weight grades that accumulate in the . In modern , PVP is incorporated into as a and viscosity enhancer, such as in products like Soothe Hydration, and into hydrogel-based contact lenses to improve wettability and comfort, reducing friction and protein deposition. For wound management, PVP-based hydrogels and dressings, often combined with , facilitate sustained antiseptic release and promote healing by maintaining a moist environment. Recent advancements leverage PVP in drug carriers for targeted delivery, enhancing and stability. For instance, PVP-coated s loaded with have shown controlled release and improved efficacy in tissue-specific applications, with 2023 studies demonstrating their integration into 3D scaffolds for localized . PVP's enables such systems to minimize off-target effects while boosting drug and circulation time. The U.S. Food and Drug Administration (FDA) classifies PVP as (GRAS) for oral and topical administration, supported by pharmacokinetic data indicating low systemic absorption—typically less than 1% following oral intake—and minimal due to its large molecular size and poor gastrointestinal uptake.

Industrial and Technical Applications

Polyvinylpyrrolidone (PVP) functions as a key in slurries, where it stabilizes suspensions by adsorbing onto particle surfaces to prevent agglomeration through steric hindrance. This role is particularly vital in additive manufacturing processes, such as vat photopolymerization, enabling the production of high-density components with uniform microstructures. In synthesis for industrial inks, PVP serves as a capping and dispersing agent, stabilizing metal particles like silver and gold to maintain colloidal stability and control . For instance, in formulating conductive inks, PVP reduces , ensuring reliable jetting and deposition in applications. As an adhesive component, is incorporated into photo-quality papers and protective coatings, where its film-forming capabilities provide strong interfacial bonding and . In inkjet printing on photo paper, PVP not only stabilizes suspensions but also enhances adhesion to substrates, improving print resolution and longevity. In battery manufacturing, PVP acts as a binder in formulations, promoting uniform dispersion of active materials and enhancing mechanical cohesion during cycling. Research demonstrates that PVP-based binders in lithium-ion and sodium-ion batteries improve electrode integrity and electrochemical efficiency by mitigating volume changes in active materials. PVP contributes to oil drilling fluids as a viscosifier, elevating and to support efficient cuttings transport and wellbore stability under extreme conditions. When combined with polymers like , PVP exhibits synergistic effects that amplify fluid thickening, reducing fluid loss and enhancing overall performance in high-temperature environments. Its rheological behavior further aids in maintaining suspension stability in these dynamic systems. In recent developments as of 2024, PVP has been integrated into resins for industrial applications, where its supports the fabrication of functional prototypes and components requiring material safety. Hybrid PVP formulations in photopolymerizable resins improve dispersion of fillers and enhance print fidelity, particularly in processes like direct ink writing for .

Consumer and Food Products

Polyvinylpyrrolidone (PVP) serves as a film-forming agent in products such as sprays and shampoos, where it provides hold and structure to styled at concentrations typically ranging from 0.5% to 2%. This property arises from its ability to form flexible, transparent films upon drying, enhancing product performance without compromising flexibility. In addition, PVP acts as a stabilizer in toothpastes, where it increases and prevents separation, and in deodorants, where it aids in stability and conditioning. As a food additive designated E1201, PVP functions as a thickener in syrups and other liquid formulations, improving texture and stability. The Joint FAO/WHO Expert Committee on Food Additives (JECFA) has established an acceptable daily intake (ADI) for PVP of 0-50 mg/kg body weight, reflecting its low toxicity profile. In household detergents, PVP is incorporated as a dye transfer inhibitor, complexing with loose dyes during laundering to prevent color bleeding onto fabrics. Recent advancements as of 2025 include eco-friendly PVP formulations in natural cosmetics, such as bio-based variants that reduce environmental impact while maintaining film-forming efficacy in hair and skin products. PVP's sensory benefits stem from its non-toxic, odorless nature and ability to enhance product texture, providing a smooth, non-greasy feel in creams, gels, and oral care items.

Safety, Toxicology, and Environmental Impact

Human Health Effects

Polyvinylpyrrolidone (PVP) demonstrates low across multiple exposure routes. The oral LD50 in rats exceeds 100 g/kg body weight, indicating minimal risk from , while dermal and exposures show no significant adverse effects at tested doses. PVP is generally non-irritating to skin and eyes, with studies confirming no corrosive or sensitizing potential under standard conditions. Chronic exposure to PVP is associated with rare reactions, including , particularly in formulations combined with iodine such as , where PVP itself may act as the rather than iodine. These immediate-type reactions occur infrequently, with reported cases often overlooked due to diagnostic challenges, and true incidence remains below 1% in susceptible individuals. Occupational exposure primarily occurs via of dust or aerosols, with recommended limits including an ACGIH of 3 mg/m³ (8-hour time-weighted average, respirable fraction) to prevent respiratory irritation. Following intravenous administration, PVP exhibits in the , including the liver, spleen, and lymph nodes, due to its high molecular weight and poor renal clearance. The in humans involves gradual elimination primarily via over months for retained fractions, though trace amounts may persist long-term without evident toxicity in most cases. PVP is not classified as carcinogenic to humans by the International Agency for Research on Cancer (IARC Group 3), based on limited evidence from showing no systemic tumors at high doses. PVP shows no genotoxic potential, with negative results in and assays for DNA damage or mutagenicity across various molecular weights, as per the EFSA re-evaluation. However, investigations into long-term retention highlight the need for monitoring in the kidneys, where low-molecular-weight PVP may cause transient functional changes without overt after acute infusion, emphasizing clearance pathways in pharmaceutical applications.

Environmental Fate and Regulations

Polyvinylpyrrolidone (PVP) exhibits low biodegradability in aquatic environments, with biodegradation rates below 10% after 28 days in standardized tests such as 301D, 301F, and extended 42-day assays using or secondary effluent. This limited degradation is attributed to the stability of its bonds, which resist microbial breakdown under typical environmental conditions. PVP demonstrates slow in and , contributing to its persistence with estimated half-lives ranging from several months to years, though specific quantitative data for the polymer remain limited compared to its . Ecotoxicological assessments indicate low of PVP to aquatic organisms. For , such as juvenile , the LC50 exceeds 1000 mg/L over 96 hours, while for marine algae, the surpasses 1000 mg/L over 72 hours. PVP shows no significant potential, as its (log Kow) is negative or below 1 (e.g., approximately -0.71), favoring in over partitioning into . PVP is regulated under major chemical frameworks to manage environmental releases. In the , it is registered under REACH (EC/List no. 618-363-4, CAS 9003-39-8), requiring notification of environmental hazards and risk assessments for uses. In the United States, PVP is listed as an active substance on the TSCA inventory, subjecting it to reporting for significant new uses that could impact the environment. In , PVP can be effectively removed through adsorption processes, achieving efficiencies of 70-90% using materials like acidic clays or , which bind the polymer via hydrogen bonding and electrostatic interactions. This removal prevents downstream ecological exposure, though incomplete treatment may lead to persistence in receiving waters. Recent efforts address PVP's environmental persistence, particularly its contribution to microplastic-like pollution. Initiatives in 2024-2025 focus on developing bio-based alternatives, such as plant-derived pyrrolidone polymers, to replace petroleum-sourced PVP and enhance degradability while maintaining functionality in applications.

History and Development

Discovery and Early Synthesis

The groundwork for polyvinylpyrrolidone (PVP) was laid by advances in vinyl chemistry during the 1930s, particularly through Walter Reppe's pioneering high-pressure reactions involving at in , . These developments enabled the synthesis of the key monomer, N-vinylpyrrolidone, from , , and 2-pyrrolidone derivatives. In late 1938 or early 1939, Reppe succeeded in polymerizing N-vinylpyrrolidone via free-radical initiation to produce PVP, a water-soluble, non-ionic with unique binding and solubilizing properties. This breakthrough was patented, filed on May 28, 1940, and issued on December 9, 1941 (US Patent 2,265,450), marking the formal invention of the as part of Reppe's broader chemistry research. The primary motivation for PVP's development stemmed from the urgent demand for synthetic substitutes amid , when shortages of human plasma threatened military medical care. BASF researchers targeted a biocompatible that could expand without triggering immune responses, leveraging PVP's physiological inertness and ability to mimic plasma proteins. Initial medical trials began in 1943–1944, primarily in , where PVP solutions were administered intravenously to wounded soldiers, demonstrating efficacy in maintaining circulation and reducing shock. These early applications confirmed PVP's potential as a temporary plasma expander, though long-term accumulation concerns later limited its routine use. Early synthesis efforts faced significant hurdles, including side reactions and incomplete conversion in the nascent . Purification was particularly challenging, as the highly hygroscopic product required meticulous removal of unreacted and initiators to prevent contamination, often involving repeated precipitation from organic solvents or dialysis. These issues necessitated iterative refinements in reaction conditions, such as controlled temperature and initiator concentrations, to improve scalability before wartime deployment.

Commercialization and Recent Advances

Following , initiated commercial production of polyvinylpyrrolidone (PVP) in 1951 at its Ludwigshafen facility in , marking the polymer's entry into industrial-scale manufacturing after its initial synthesis in the late 1930s. This launch capitalized on PVP's and , quickly positioning it as a key ingredient in pharmaceutical formulations, such as binders and solubilizers, during the 1950s. By the 1960s, expanded PVP's commercialization into , where it served as a film-former in hair sprays and styling products, driving broader market adoption beyond medical uses. Key milestones in PVP's commercialization included its approval as a in the under the designation E1201 in the late , enabling its use as a stabilizer in dietary supplements and beverages. In the , PVP gained traction in emerging applications, particularly as a stabilizing agent in the synthesis of metal nanoparticles for biomedical imaging and systems. The saw further innovation with PVP's incorporation into biotech formulations, including microneedle patches for thermostable mRNA , enhancing delivery efficiency and shelf-life in immunization technologies. These developments were supported by foundational patents, such as those filed by BASF's Walter Reppe in the for PVP synthesis processes. PVP's global market has expanded dramatically since its post-war inception, from modest production volumes in the early to approximately 18,000 metric tons annually by 2024, with projections reaching around 20,000-25,000 tons by 2025. This growth has been propelled by rising demand in , which accounted for the largest regional share in 2024 due to expanding pharmaceutical and personal care sectors in countries like and . Recent advances from 2023 to 2025 emphasize sustainable production, with industry leaders investing in methods to reduce energy use and incorporate renewable feedstocks, aligning with global environmental regulations.

Derivatives and Modifications

Cross-linked Variants

Cross-linked variants of polyvinylpyrrolidone (PVP), commonly known as crospovidone, are insoluble homopolymers produced by modifying linear PVP through cross-linking processes. These variants are synthesized either by incorporating divinyl compounds, such as N,N'-divinylimidazolidinone or divinyl glycol, during the of N-vinylpyrrolidone (NVP), or by applying , such as gamma or beam , to pre-formed linear PVP chains. The chemical cross-linking method involves heating mixtures of NVP, water, the divinyl agent (typically 0.1-2% by weight), and a initiator like dibenzoyl peroxide at temperatures rising from 35°C to 102°C, followed by washing and drying to yield a white, porous powder with yields around 90%. cross-linking, on the other hand, exposes aqueous solutions of linear PVP (concentrations of 1.5-10 wt%) to doses of 25-75 kGy, generating radicals that form covalent bonds between polymer chains without additional agents, resulting in gel-like structures that are then processed into powders. Commercial examples include Polyplasdone™ from Ashland, which employs proprietary cross-linking to achieve controlled particle morphologies. The primary properties of cross-linked PVP stem from the three-dimensional network formed by s, rendering it completely insoluble in and most organic solvents, in contrast to the soluble linear PVP. This insolubility enables unique applications reliant on hydrophilicity without dissolution. Upon , crospovidone exhibits rapid swelling due to water ingress into its porous matrix, achieving expansions up to 300%, with reported as high as 5 mL per gram of dry material depending on cross-link density and . The structure features intra-particle pores typically ranging from 10-100 nm, which facilitate high adsorption capacity by allowing efficient trapping of molecules and ions through and surface interactions, while the overall (25-100 µm) influences water uptake rates. Unlike linear PVP, which dissolves readily, the cross-linked form maintains structural integrity, providing mechanical stability during swelling without forming viscous gels. The extent of cross-linking is quantified by the degree of cross-linking, defined as the of moles of divinyl cross-linker to the total moles of vinyl monomers in the feed: Degree of cross-linking=moles of divinyl cross-linkertotal moles of vinyl monomers\text{Degree of cross-linking} = \frac{\text{moles of divinyl cross-linker}}{\text{total moles of vinyl monomers}} This metric directly correlates with swelling ; higher ratios (e.g., 1.6 mol%) reduce and pore by tightening the network, while lower ratios enhance flexibility and retention. Cross-linking can also be derived post-formation using the , where νx=1/(vˉMc)\nu_x = 1 / (\bar{v} M_c), with νx\nu_x as cross-link , vˉ\bar{v} as specific , and McM_c as average molecular weight between cross-links, often determined via swelling equilibrium measurements. A key limitation of cross-linked PVP is its complete loss of solubility compared to linear PVP, which restricts its use in applications requiring dissolution, such as solubilizing agents in aqueous formulations. This insolubility, while advantageous for swelling-based functions, can complicate processing in high-humidity environments due to hygroscopicity and potential agglomeration, necessitating controlled manufacturing conditions.

Copolymers and Functionalized Forms

Polyvinylpyrrolidone (PVP) forms various copolymers through free-radical with other monomers, enabling tailored properties such as adjusted and film-forming capabilities. A prominent example is the of vinylpyrrolidone (VP) and (VA), known as PVP/VA, which is synthesized in ratios ranging from 70:30 to 30:70 VP:VA to balance hydrophilicity and hydrophobicity. The 50:50 VP:VA ratio is particularly valued in hair fixatives for its ability to form hard, glossy, oxygen-permeable films with strong to , providing hold while maintaining flexibility and moisture resistance. In this composition, the VP units enhance and film gloss, while VA units improve water resistance and thermoplasticity, with temperatures around 100–110°C. Another common copolymer is poly(1-vinylpyrrolidone-co-styrene), produced as a stable 38% aqueous with particle sizes below 0.5 μm, offering high acid and salt tolerance. This , containing approximately 64 wt.% styrene on a dry basis, forms strong, light-stable films with excellent water resistance, making it suitable for emulsion-based applications requiring durable coatings. Functionalization of PVP often involves quaternization to introduce cationic properties, as seen in polyquaternium-11, a quaternized of VP and dimethylaminoethyl . This derivative acts as an by reducing static buildup on hair and fabrics through its polymeric quaternary ammonium structure, while also serving as a film-former and conditioner in cosmetic formulations. Graft copolymers, such as those combining PVP with (PEG), are prepared via of N-vinyl-2-pyrrolidone onto PEG chains, confirmed by FTIR showing hydrogen-bonding interactions. These PVP-PEG grafts enhance and control release profiles, with applications in systems like hydrogels modified with cyclodextrins for sustained release of water-soluble drugs, where PEG improves swelling and PVP provides matrix stability. Copolymerization ratios significantly influence properties; for instance, a 60:40 VP:VA ratio achieves an optimal solubility balance for hydrophobic actives, increasing their solubility up to 30-fold compared to alone, as VP content drives hydrophilic interactions while VA moderates it. Emerging developments include biodegradable PVP-chitosan composites for , formed as hydrogels incorporating bimetallic metal-organic framework nanocages (30–50 nm). These matrices, leveraging chitosan's natural degradability and PVP's , promote rapid —up to 69% in 7 days—by reducing (e.g., lowering IL-1β), upregulating TGF-β and deposition, and providing antibacterial moisture balance, with full closure in 10 days in preclinical models.

References

  1. https://pmc.ncbi.nlm.nih.gov/articles/PMC7462970/
  2. https://www.researchgate.net/publication/278377732_Polyvinylpyrrolidone_-_A_Versatile_Polymer_for_Biomedical_and_Beyond_Medical_Applications
  3. https://pubmed.ncbi.nlm.nih.gov/12376866/
  4. https://pubchem.ncbi.nlm.nih.gov/compound/N-vinyl-2-pyrrolidone
  5. https://www.chemicalbook.com/article/what-are-the-synthesis-methods-of-n-vinyl-2-pyrrolidone.htm
  6. https://www.nature.com/articles/pj198512.pdf
  7. https://www.sciencedirect.com/science/article/abs/pii/0032386185901430
  8. https://www.nature.com/articles/pj198512
  9. https://doi.org/10.1295/polymj.17.143
  10. https://pubs.acs.org/doi/10.1021/acs.macromol.8b01627
  11. https://onlinelibrary.wiley.com/doi/10.1002/9781119468769.hpcbm006
  12. https://www.sciencedirect.com/science/article/abs/pii/0032395078903349
  13. https://onlinelibrary.wiley.com/doi/10.1002/pol.1981.130190106
  14. https://pubs.acs.org/doi/abs/10.1021/jacs.0c08528
  15. https://www.carlroth.com/medias/SDB-CP15-MT-EN.pdf
  16. https://www.sciencedirect.com/science/article/pii/S2772421223000247
  17. https://www.chemicalbook.com/article/chemical-properties-of-polyvinylpyrrolidone.htm
  18. https://www.mdpi.com/2411-5134/6/4/61
  19. https://www.shokubai.co.jp/en/products/detail/pvp/
  20. https://pmc.ncbi.nlm.nih.gov/articles/PMC4766119/
  21. https://link.springer.com/article/10.1007/s10973-019-08030-0
  22. https://pdfs.semanticscholar.org/3c09/f25aee3e1b7b9c71cfe11f7a4fe1dd2c5c7e.pdf
  23. https://www.researchgate.net/publication/251304852_A_TGFTIR_study_on_the_thermal_degradation_of_polyvinyl_pyrrolidone
  24. https://pubs.rsc.org/en/content/articlelanding/2017/en/c7en00411g
  25. https://pubs.acs.org/doi/10.1021/acsapm.2c00796
  26. https://onlinelibrary.wiley.com/doi/abs/10.1002/pol.1952.120080508
  27. https://www.chemanalyst.com/industry-report/povidone-market-4186
  28. https://www.reanin.com/reports/polyvinylpyrrolidone-market
  29. https://www.ashland.com/industries/personal-and-home-care/home-i-and-i/pvp-k-series
  30. https://www.usp.org/
  31. https://www.atamanchemicals.com/polyvinylpyrrolidone-k90-povidone-pvp-k-90_u34505/
  32. https://datasheets.scbt.com/sc-203204.pdf
  33. https://www.accio.com/plp/pvp-polyvinylpyrrolidone
  34. https://www.factmr.com/report/3500/polyvinylpyrrolidones-pvp-market
  35. https://www.made-in-china.com/manufacturers/polyvinylpyrrolidone-pvp.html
  36. https://www.pharmaexcipients.com/news/reworking-potential-polyvinylpyrrolidone/
  37. https://pmc.ncbi.nlm.nih.gov/articles/PMC7285361/
  38. https://www.sciencedirect.com/topics/nursing-and-health-professions/povidone-iodine
  39. https://pubmed.ncbi.nlm.nih.gov/38036066/
  40. https://pmc.ncbi.nlm.nih.gov/articles/PMC10820039/
  41. https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?fr=173.55
  42. https://www.sciencedirect.com/science/article/pii/S000186862400174X
  43. https://pubs.acs.org/doi/10.1021/acsomega.0c04010
  44. https://www.sciencedirect.com/science/article/abs/pii/S0360319912019556
  45. https://pmc.ncbi.nlm.nih.gov/articles/PMC7997470/
  46. https://www.sciencedirect.com/science/article/pii/S0378775324011297
  47. https://pubs.acs.org/doi/10.1021/acsaem.5c00251
  48. https://www.sciencedirect.com/science/article/abs/pii/S2213397616000161
  49. https://www.sciencedirect.com/science/article/abs/pii/S0377025720301567
  50. https://www.sciencedirect.com/science/article/abs/pii/S0141813024053339
  51. https://www.nature.com/articles/s41467-024-46532-0
  52. https://www.cir-safety.org/sites/default/files/PVP_RR.pdf
  53. https://www.specialchem.com/cosmetics/inci-ingredients/pvp
  54. https://www.eschemy.com/news/what-is-polyvinyl-pyrrolidone-pvp-in-toothpaste
  55. https://www.yearnintl.com/problems/the-application-of-pvp-in-cosmetics-industry/
  56. https://www.fao.org/gsfaonline/additives/details.html?id=266
  57. https://www.inchem.org/documents/jecfa/jeceval/jec_1957.htm
  58. https://www.ashland.com/industries/personal-and-home-care/home-i-and-i/pvp-k30-30-solution
  59. https://www.eschemy.com/news/innovative-applications-and-trends-of-polyvinylpyrrolidone-pvp-in-the-korean-cosmetics-industry
  60. https://www.fishersci.com/store/msds?partNumber=BP431100&productDescription=PVP%2B100G&vendorId=VN00033897&countryCode=US&language=en
  61. https://cdn.gbiosciences.com/pdfs/msds/RC-085_msds.pdf
  62. https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/polyvinylpyrrolidone
  63. https://pubmed.ncbi.nlm.nih.gov/18204285/
  64. https://www.ncbi.nlm.nih.gov/books/NBK498761/
  65. https://publications.iarc.who.int/_publications/media/download/2337/b1742948f09b78a4af350feb39bfee70dec7ac2b.pdf
  66. https://monographs.iarc.who.int/wp-content/uploads/2018/06/Supplement7.pdf
  67. https://pmc.ncbi.nlm.nih.gov/articles/PMC7416752/
  68. https://pmc.ncbi.nlm.nih.gov/articles/PMC11953058/
  69. https://www.researchgate.net/publication/390286157_Changes_in_kidney_functions_following_acute_infusion_of_low_molecular_weight_polyvinylpyrrolidone_in_male_rats
  70. https://doi.org/10.1016/j.chemosphere.2024.143739
  71. https://www.cosmeticsandtoiletries.com/testing/safety-stability/article/21837310/getting-the-breakdown-testing-the-biodegradation-and-styling-performance-of-polyurethane-film-formers
  72. https://echa.europa.eu/substance-information/-/substanceinfo/100.111.937
  73. https://www.sigmaaldrich.com/sds/sial/pvp40
  74. https://link.springer.com/article/10.1346/CCMN.2018.064079
  75. https://www.towardschemandmaterials.com/insights/polyvinylpyrrolidone-market
  76. https://patents.google.com/patent/US2265450A/en
  77. https://www.sciencedirect.com/science/article/pii/S2666821120300181
  78. https://www.btc-europe.com/en/newsroom/article/polyvinylpyrrolidone-pvp-a-multi-talent-turns-seventy
  79. https://efsa.onlinelibrary.wiley.com/doi/10.2903/j.efsa.2020.6215
  80. https://www.nature.com/articles/s41587-023-01774-z
  81. https://www.grandviewresearch.com/industry-analysis/polyvinylpyrrolidone-market
  82. https://www.mordorintelligence.com/industry-reports/polyvinylpyrrolidone-market
  83. https://www.researchgate.net/publication/251464903_Crospovidone
  84. https://www.ashland.com/industries/pharmaceutical/oral-solid-dose/polyplasdone-crospovidone
  85. https://pmc.ncbi.nlm.nih.gov/articles/PMC8774647/
  86. https://www.sciencedirect.com/topics/pharmacology-toxicology-and-pharmaceutical-science/crospovidone
  87. https://www.pharmaexcipients.com/wp-content/uploads/attachments/PC_11319_Polyplasdone_Overview.pdf
  88. http://repositorio.ipen.br/bitstream/handle/123456789/5798/10424.pdf?sequence=1
  89. https://www.ashland.com/file_source/Ashland/images/PHA19-021.1%20Agrimer%20VA%20Ag%20Brochure.pdf
  90. https://pubmed.ncbi.nlm.nih.gov/26826280/
  91. https://www.sigmaaldrich.com/US/en/product/aldrich/434450
  92. https://www.cosmeticsinfo.org/ingredient/polyquaternium-11/
  93. https://www.researchgate.net/publication/257593432_Preparation_and_Application_of_PEGPVP_Copolymers
  94. https://www.tandfonline.com/doi/full/10.1080/10717540802605129
  95. https://www.sciencedirect.com/science/article/abs/pii/S0141813024094832
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