5.2. POVIDONE78, 79:
Nonproprietary Names: BP: Povidone, USP: Povidone
Synonyms: E1201; Kollidon; Plasdone; poly[1-(2-oxo-1-pyrrolidinyl)ethylene]; polyvidone; polyvinylpyrrolidone; PVP; 1-vinyl-2-pyrrolidinone polymer.
Chemical Name and CAS Registry Number: 1-Ethenyl-2-pyrrolidinone homopolymer [9003-39-8]
Empirical Formula and Molecular Weight: (C6H9NO)n 2500–3 000 000
The USP 28 describes povidone as a synthetic polymer consisting essentially of linear 1- vinyl-2-pyrrolidinone groups, the differing degree of polymerization of which results in polymers of various molecular weights.
Structural Formula: Functional Category: Disintegrant; dissolution aid; suspending agent; tablet binder.
Applications in Pharmaceutical Formulation or Technology:
…show more content…
Particle size distribution: Kollidon 25/30: 90% >50 μm, 50% >100 μm, 5% >200 μm; Kollidon 90: 90% >200 μm, 95% >250 μm
Viscosity (dynamic) : The viscosity of aqueous povidone solutions depends on both the concentration and the molecular weight of the polymer employed
Solubility: Freely soluble in acids, chloroform, ethanol (95%), ketones, methanol, and water; practically insoluble in ether, hydrocarbons, and mineral oil. In water, the concentration of a solution is limited only by the viscosity of the resulting solution, which is a function of the K-value.
Stability and Storage Conditions: Povidone darkens to some extent on heating at 150°C, with a reduction in aqueous solubility. It is stable to a short cycle of heat exposure around 110–130°C; steam sterilization of an aqueous solution does not alter its properties. Aqueous solutions are susceptible to mold growth and consequently require the addition of suitable preservatives. Povidone may be stored under ordinary conditions without undergoing decomposition or degradation. However, since the powder is hygroscopic, it should be stored in an airtight container in a cool, dry
…show more content…
Stability and Storage Conditions:
Hypromellose powder is a stable material, although it is hygroscopic after drying. Solutions are stable at pH 3–11. Aqueous solutions are comparatively enzyme-resistant, providing good viscosity stability during long-term storage. However, aqueous solutions are liable to microbial spoilage and should be preserved with an antimicrobial.
5.4. EUDRAGIT NE 40 D81-82:
Nonproprietary Names: Polyacrylate Dispersion 40 Per Cent Ph. Eur.
Chemical structure: Eudragit NE 40 D is the aqueous dispersion of a neutral copolymer based on ethyl acrylate and methyl methacrylate. The average molar mass is approx. 750,000 g/mol.
Description:
Milky-white liquid of low viscosity with a faint characteristic odour. It is highly permeable polymer and is very flexible polymer. It is available in the 40% dispersion form and it already contains plasticizer, so there is no need to add plasticizer in the formulation containing Eudragit NE 40