Chemistry name: Crospovidone; PVPP

CAS No.: 9003-39-8

EINECS No.: 1312995-182-4

Chemical formula:  [C6H9NO]n

Molecular mass: 111.14

Definition:

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EXCfiller®Crospovidone(PVPP) is an insoluble, three-dimensional, polymeric network that is formed through the cross-linking of N-vinylpyrrolidone (NVP) monomers. It lacks a defined repeating unit, with the pyrrolidone ring serving as the core functional group. PVPP has many applications in the food industry, including as a clarifying agent, food stabiliser and dietary fibre additive. In the pharmaceutical sector, its main uses are as a disintegrant for oral formulations, a drug carrier, a cosmetic stabiliser and a water treatment agent.

■ Source

The production of EXCfiller®Crospovidone typically involves a synthetic process using various raw materials. The polymerisation monomer is N-vinylpyrrolidone (NVP), which is obtained through industrial synthesis using either the acetylene or γ-butyrolactone method. The purity requirement is ≥99.5% (GC detection). The crosslinking agent comprises divinylbenzene (DVB) and ethylene glycol dimethacrylate, which are sourced as industrial-grade crosslinking agents with a purity requirement of ≥98.0% (GC analysis). The initiators are benzoyl peroxide (BPO) and azobisisobutyronitrile (AIBN), which are sourced as food-additive-grade initiators with a purity requirement of ≥98.5%. The solvents are deionised water and ethanol, with purity requirements of conductivity of ≤10 μS/cm for water and ≥95% for ethanol.

Particularities of EXCfiller®Crospovidone:

Product Specifications:

EXCfiller®Crospovidone is available in the following specification and contents:

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☑ EXCfiller®Crospovidone (40-130 μm)

Product quality standards:

● USP, EP, BP, CP, Food grade, In-house

EXCfiller®Crospovidone Applications:

In pharmaceutical applications, the core functions of EXCfiller®Crospovidone are disintegration, dissolution enhancement and stability improvement. It is primarily used as a disintegrant in oral formulations. Although it is insoluble in water, PVPP has exceptional water absorption and swelling properties, expanding 300-500 times its original volume upon hydration. Through capillary action, it rapidly absorbs moisture to form a porous structure within tablets and capsules. This generates internal stresses that disrupt the formulation's structure, promoting rapid disintegration. As a drug dissolution enhancer, PVPP's three-dimensional network structure adsorbs poorly soluble drug molecules, thereby increasing the drug's specific surface area and preventing particle aggregation. This facilitates rapid dissolution within the gastrointestinal tract. As a formulation stability enhancer, PVPP adsorbs trace impurities in the drug, such as metal ions and oxidation products, as well as irritants within the gastrointestinal tract. This reduces drug degradation and lowers the risk of adverse reactions. As a carrier for controlled-release formulations, it can regulate the release rate of drugs by adjusting the degree of crosslinking (85-90%) and the particle size (100-150 μm), thus enabling sustained-release administration.

​​​​​​​Core functions in food applications include clarification, stabilisation and supplementation with dietary fibre. As a beverage clarifier, PVPP is preferred in the beer and juice industries. Its pyrrolidone ring forms hydrogen bonds with polyphenolic compounds (such as tannins and anthocyanins) in beverages. These bonds absorb and remove the components that cause cloudiness and sedimentation, thereby enhancing clarity and stability. As a food stabiliser and quality enhancer, PVPP's three-dimensional network structure absorbs moisture and lipids within foodstuffs, improving texture and extending shelf life. As a dietary fibre supplement, PVPP is not digested by human enzymes and serves as a water-soluble dietary fibre with a dietary fibre content of at least 90%, promoting intestinal motility and increasing satiety. As an antioxidant adjuvant in food, PVPP adsorbs oxygen free radicals and oxidation products within foodstuffs, thereby delaying the oxidative deterioration of components such as fats and vitamins.

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■ Production technology characteristics

The core process in EXCfiller®Crospovidone production is the polymerisation reaction involving the cross-linking of N-vinylpyrrolidone (NVP) monomers. Crosslinking agents (such as divinylbenzene or ethylene glycol dimethacrylate) are introduced into the NVP polymerisation system to connect the linear PVPP molecular chains via covalent bonds, forming a three-dimensional insoluble polymer network. This is then processed to produce a powder with a specific particle size and degree of crosslinking. The reaction fundamentally involves free-radical polymerisation, which requires initiation by agents such as benzoyl peroxide or azobisisobutyronitrile. Strict control of polymerisation conditions is essential to ensure consistent product performance.

Solvent polymerisation is the preferred process for producing food-grade PVPP. When water or ethanol is used as the solvent, the NVP monomer, crosslinking agent and initiator are dissolved in it. Homogeneous polymerisation is then conducted under specific temperature and stirring conditions. After the reaction, the solvent and any soluble impurities are removed by filtration, washing and drying, yielding insoluble PVPP. Solid-phase polymerisation is the process used for producing pharmaceutical-grade, low-residue PVPP. This process requires no solvent and involves blending the NVP monomer, crosslinking agent and initiator in precise proportions. Polymerisation is initiated by heating the solid-phase mixture. The system exhibits no fluidity during the reaction and relies on mechanical stirring to ensure thorough material homogeneity.

​​​​​​​This yields high-purity, low-residue PVPP. Reverse suspension polymerisation is used to produce specialised forms of PVPP. An oil phase (e.g. paraffin oil or cyclohexane) is used as the dispersion medium and an aqueous solution of NVP monomer, crosslinking agent and initiator serves as the water phase. An emulsifier (e.g. Span 80) is then added to disperse the water phase into minute droplets (1-10 μm in size). Under stirring conditions, non-homogeneous polymerisation occurs to form spherical PVPP microspheres.

☑ EXCfiller®Crospovidone (10-50 μm)