Vinyl pyrollidone

In another study, uniform composite polymethyl-methacrylate/polystyrene (PMMA/PS) composite particles in the size range of 1-10 fim were prepared by the seeded emulsion polymerization of styrene [121]. The PMMA seed particles were initially prepared by the dispersion polymerization of MMA by using AIBN as the initiator. In this polymerization, poly(7V-vinyl pyrolli-done) and methyl tricaprylyl ammonium chloride were used as the stabilizer and the costabilizer, respectively, in the methanol medium. Seed particles were swollen with styrene monomer in a medium comprised of seed particles, styrene, water, poly(7V-vinyl pyrollidone), Polywet KX-3 and aeorosol MA emulsifiers, sodium bicarbonate, hydroquinone inhibitor, and azobis(2-methylbu-... 

The preceding results on polycarbonate are at variance with the ultrasonic degradation of poly(vinyl pyrollidone) prepared with peroxide linkages where the rate of chain cleavage was determined to be 5000 times faster at the — 0 — 0 — than the — C —C— bonds [164]. 

Cellulose disintegrants have been studied as insoluble matrices for sustained release tablets. Anionically charged carboxymethyl cellulose (sodium salt) was found to be inferior to methyl cellulose and poly(vinyl pyrollidone) as a binding agent for oxyphenbutazone tablets [291], However sodium carboxymethyl cellulose has found application as a dispersing agent for ibuprofen microspheres... 

Similarly comb-like copolymers of vinyl pyrollidone and vinyl alkyl amines were shown [446] to influence the permeability of negatively charged phospholipid liposomes containing encapsulated carboxyfluorescein. At a pH of approximately 7, the copolymers allowed permeability and solute release due to polymer/liposome complex formation and disruption of the phospholipid membrane. 

The polymeric dispersants included random copolymers of long chain alpha olefins or long chain methacrylates with acidic or basic co-monomers such as vinyl acetate, vinyl alcohol, vinyl pyridine, vinyl pyrollidone, hydroxyethyl methacrylate, etc. The alpha-olefin vinyl acetate copolymers had molecular weights in the 1-25,000 range and the methacrylates were in the 100,000 + range. All were oil soluble and reduced the oil-water interfacial tension appreciably. 

Tenax GC sorbent has a known upper temperature limit of350 °C. It is a commonly used adsobent because of its high upper temperature limit and low background on desorption. Tenax is a porous polymer of 2,6-diphenyl phenol and has a packed density of approximately 0.22 g/mL (60/80 mesh). Chromosorb 106 is a cross-linked polystyrene porous polymer. It has a published upper temperature limit of 250 °C and a packed density of approximately 0.39 g/mL (60/80 mesh). Porapak N sorbent is a styrene/divinyl benzene porous polymer in wich vinyl pyrollidone is added to increase its polarity. The published upper temperature limit of Porapak N is 190 °C. Porapak N has a packed density of approximately 0.42 g/mL (60/80 mesh). Carbosieve B sorbent is a synthetic carbon molecular sieve and is one of the most retentive solid adsorbents available. It has an upper temperature limit of at least 400 °C and a packed density of approximately 0.22 g/mL (60/80 mesh). 

Tunney MM, Gorman SP. Evaluation of a poly(vinyl pyrollidone)-coated biomaterial for urological use. Biomaterials December 2002 23(23) 4601-8. 

Porapak R Vinyl pyrollidone 250 Separation of ethCTS and esters ... 

The monomers which have been investigated include methyl methacrylate, ethyl acrylate ester, hydroxy acrylates and methacrylates, acrylonitrile, vinyl acetate, vinyl chloride, acrylamide, vinylidene chloride, acrylic acid, vinyl pyrollidone and styrenec Many copolymer latexes of these monomers have also been preparedc Undoubtedly the most amenable system for model studies is methyl methacrylate in aliphatic hydrocarbono... 

This section will cover blends of polymers, both exhibiting water solubihty. Many of the water soluble polymers have been noted in earher sections in this chapter to exhibit misci-bihty with non-water soluble polymers. These water soluble polymers include poly(ethylene oxide), poly(N-vinyl pyrollidone), poly(vinyl amine), polyacrylamide, poly(N,N-dimethyl acrylamide poly(acryhc acid), poly(methacrylic acid), poly(ethyl oxazohne), poly(styrene sulfonic acid), poly(vinyl pyridine), poly(vinyl alcohol), hydroxyl ethyl ceUulose, hydroxy propyl cellulose, carboxy methyl ceUulose, poly(itaconic acid) and poly(ethyleneimine) (several structures shown below). 

Modacryl ic fibers are formed from copolymers consisting of 35%85% acrylonitrile and a suitable vinyl comonomer or comonomers such as vinyl chloride, vinylidene chloride, vinyl acetate, vinyl pyrollidone, or methyl acrylate. The modacrylics generally resemble acrylics and have a warm pleasing hand and good drapability, resiliency and wrinkle resistance. They are more heat sensitive but more flame resistant than acrylics and have generally been used in specialty applications. Modacrylic fiber exhibits a more thermoplastic character than the related acrylic fibers. 

Polymeric drugs Poly(A vinyl pyrollidone co maleic acid), sulfonated polysaccharides [15,16]... 

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