Cross-linked polyvinylpyrrolidone

Table 11. Swelling of Cross-linked Polyvinylpyrrolidone in Various Liquids at 20°C...

Cross-linked polyvinylpyrrolidone the high molecular weight and cross-linking render the material insoluble in water... 

Crospovidone is a cross-linked homopolymer of A-vinyl-2-pyrrolidone. Acetylene and formaldehyde react to form butynediol. Hydrogenation and subsequent cyclodehydrogenation gives butyrolactone. The reaction of butyrolactone with ammonia produces pyrrolidone, which is vinylated with acetylene under pressure. The linear polymerization of the vinylpyrrolidone yields polyvinylpyrrolidone, a soluble binder, whereas the popcorn (branched) polymerization yields crospovidone, an insoluble... 

Cross-linked polyvinylpyrrolidone (PolyplasdoneXL GAF Corp., New York, USA). Castor oil (USP XXI grade C.Erba, Milano, Italy). 

Henke A, Kadlubowski S, Ulanski P, Rosiak JM, Arndt KF (2005) Radiation-induced cross-linking of polyvinylpyrrolidone-poly(acrylic acid) complexes. Nucl Instrum Methods Phys Res B 236 391-398... 

Study of Ternary Tablets Percolation theory has been developed for binary systems, however, drug delivery systems usually contain more than two components. The existence and behavior of the percolation thresholds in ternary pharmaceutical dosage forms have been studied [39] employing mixtures of three substances with very different hydrophilicity and aqueous solubility (Polyvinylpyrrolidone (PVP) cross-linked, Eudragit RS-PM, and potassium chloride). 

These dressings are sheets of three-dimensional networks of cross-linked hydrophilic polymers (polyethylene oxide, polyacrylamides, polyvinylpyrrolidone, carboxymethylcellulose, modified corn starch). Their formulation may incorporate up to 96% bound water, but they are insoluble in water and they interact by three-dimensional swelling with aqueous solutions. The polymer physically entraps water to form a solid sheet and they have a thermal capacity that provides initial cooling to the wound surface. A secondary dressing is required. 

The activating effect of cross-linked polyvinylpyrrolidone (CPVP) in reactions of bimolecular nucleophilic substitution has been studied in the interaction of BuBr with... 

Bharali, D.J. Sahoo, S.K. Mozumdar, S. Maitra, A. Cross-linked polyvinylpyrrolidone nanoparticles A potential carrier for hydrophilic drugs. J. Colloid Interface Sci. 2003, 258 (2), 415-423. 

Disintegrants encourage the rapid breakup of the granules back to their primary particle size. The compounds used are often highly water-soluble polymers and inorganic salts. Disintegrants generally absorb water quickly, swell, and break the particles apart. Cross-linked polyvinylpyrrolidones... 

Freudenberg has several technologies developed for use in LIB. One patent covers two-layer separators with differing fiber sizes. Another includes a ceramic component similar to its product offering. One talks about cross-linked polyvinylpyrrolidone particles, while another cites thermally bonded nonwovens as carrier materials for lithium battery separators. ... 

The resulting polyester is typically water soluble except when it is cross-linked through the double bonds with A-vinylpyrrolidone. Hydrolysis of the ester linkages leads to water-soluble fragments consisting of PEG and short chains of polyvinylpyrrolidone attached to fumaric acid. 

Various polymers have been successfully electrospun from solution, sol-gel suspension, or melt into ultrafine nanotibers. For example, as listed in Table 13.2, these polymers included nylon-6 [20, 21], polyacrylonitrile (PAN) [22, 23], polyethylene terephthalate (PET) [24], polyvinyl alcohol (PVA) [25], polystyrene (PS) [26, 27], polyvinylidene fluoride (PVDF) [28, 29], polyethersulfone (PES) [30], polyimides (PI) [31, 32], polyethylene oxide (PEO) [33], polyurethanes (PU) [34], polycarbonates (PC) [35], polycaprolactone (PCL) [36], polybenzimidazole (PBI) [37, 38], polyvinylpyrrolidone (PVP) [39], polytrimethylene terephthalate (PTT) [40], polyvinyl chloride (PVC) [41], polymethylmethacrylate (PMMA) [42], hydrox-ypropyl cellulose (HPC) [43], polyglycolic acid (PGA) [44], polyhydroxybutyrate (PHB) [45], cellulose acetate (CA) [46,47] and many more. To be used as filtration membranes, nanoflbers made of water-soluble polymers have to be further cross-linked after the electrospinning process. As polymers having different physical and... 

Photolithography can also give enzymatic membranes for use with ISFET. Polyvinylpyrrolidone is cross-linked with a photo-reticulating agent, 2,S-bis-(4 -azido-2 -sulfonbenzal)cyclopentanone, which traps the enzyme in the polymer upon the action of ultraviolet light [S3]. 

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