A -vinylpyrrolidone

The formation of inter- and intrapolymer complexes has also been shown to affect the polymerization kinetics. For example, Ferguson and Shah (1968) investigated the influence of intrapolymer complexation on the kinetics of AA in the presence of copolymer matrices composed of either A-vinylpyrrolidone and acrylamide or A--vi nyl pyrrol idone and styrene. The polymerization rate reaches a maximum in the vicinity of AA to VP ratio equal to one for the VP/AAm matrix. This maximum in the polymerization rate is most pronounced in the presence of copolymer with the highest content of VP. When the hydrophilic acrylamide is replaced with the more hydrophobic styrene monomer in the copolymer matrix, the observed maximum in AA polymerization rate occurred at a lower than equimolar ratio of AA to VP. The hydrophilic groups of VP were interacting with the hydrophobic nucleus consisting of the styrene units in the VP/St copolymer, and were thus unable to participate in the formation of the complex unlike in the case of VP/AAm copolymer matrix. 

Grafting of functional monomers onto fluoropolymers produced a wide variety of permselective membranes. Grafting of styrene (with the following sulfonation), (meth)acrylic acids, 4-vinylpyridine, A-vinylpyrrolidone onto PTFE films gave membranes for reverse omosis,32-34 ion-exchange membrane,35-39 membranes for separating water from organic solvents by pervaporation,49-42 as well as other kinds of valuable membranes. 

Methoxy poly(ethyleneglycol) (mPEG) was the most frequently used semitelechelic polymer for over 2 decades. It has been successfully used for the modification of various proteins, biomedical surfaces and hydrophobic anticancer drugs (for reviews see References [3,9,10]. Recently, a number of new semitelechelic (ST) polymers, such as ST-poly(A -isopropylacry-lamide) (ST-PNIPAAM) [11-15], ST-poly(4-acryloylmorpholine) (ST-PAcM) [16], ST-poly(A-vinylpyrrolidone) (ST-PVP) [17], and ST-poly[A-(2-hydroxypropyl)methacrylamide] (ST-PHPMA) [18-21] have been prepared and shown to be effective in the modification of proteins or biomedical surfaces. 

A-Vinylpyrrolidone polymers are of special interest in medicine in the process of detoxification as well as for binding and removal of undesirable metallic ions and known as chelatotherapeutic agents [34]. Free radical copolymers of poly(lV-vinylpyrrolidone) and copolymer of JV-vinylpyrrolidone and vinylacetate, vinylamine, vinylamidosuceinic arid are known to bind Cu2+ and other transition metal ions, and the resultant complexes exhibit interesting physico-chemical properties. 

Synonyms-. Vinylbutyrolactam vinylpyrrolidinone 1-vinylpyrrolidinone iV-vinyl-pyrrolidinone l-vinyl-2-pyrrolidinone A-vinyl-2-pyrrolidinone vinylpyrrolidone A-vinylpyrrolidone 1 -vinyl-2-pyrrolidone... 

Hybrid organic-inorganic polymer-polymer composites were prepared by blending with poly(A-vinylpyrrolidone) (PVPr), poly(4-vinylpyridine) (PVPy) and poly(ethyl oxazoline) (PEOx). It was found that the properties of these hybrids depended strongly on the preparation conditions.14... 

During dispersion polymerization polymer particles are formed from an initially homogeneous reaction mixture by polymerization in the presence of a polymeric steric stabilizer. The process is applicable to monomers which yield polymers that are insoluble in a solvent for the monomer. Styrene has been polymerized in alcohols, with steric stabilizers such as poly(A -vinylpyrrolidone) (see Fig. 1-4 for monomer structure) or hydroxypropyl cellulose. Hydrocarbon... 

Some other interesting copolymers having properties of PVC thermal stabUizers, like poly[Af-(a-benzothiazolonylmethyl)methacrylate-co-methyl methacrylate] [45], of flame retardants like a terpolymer of styrene, acrylonitrile and a polymerizable perbrominated phenol [76] or poly[4-methacryloyloxy-2,3,5,6-tetrabromobenzyldi-phenyl phosphonate-co-methyl methacrylate] [104] (93), bioddes, mostly copolymers of monomers containing tris(n-butyl tin) or triphenyl tin moieties and alkyl acrylates, methacrylates, vinyl acetate, acrylonitrile, styrene or A-vinylpyrrolidone [105], e.g. a terpolymer of styrene, MMA and tri(n-butyl tin) itaconate [106] (94),... 

Indeed, photopolymerization of acrylamide in aqueous solution on cell-GEHMP gives cellulose with the surface covered by a poly acrylamide) gel. Similarly, UV initiated polymerization of 2-hydroxyethyl acrylate, 2-(dimethylamino) ethyl methacrylate and A -vinylpyrrolidone carried out with the above functionalized Si(>2 results in the formation of a surfece polymer coating. 

Bloor, D.M. HoUwarth, J.F. Wyn-Jones, E. Polymer/ surfactant interactions the use of isothermal titration calorimetry and EMF measurements in the sodium dodecyl sulphate/poly(A-vinylpyrrolidone) system. Langmuir 1995, 11, 2312-2313. 

Huglin, M.B. Rehab, M.M.A.M. Mechanical and thermodynamic properties of butyl acrylate-A-vinylpyrrolidone hydrogels. Polymer 1987, 28, 2200-2206. 

Being so attractive, efforts to confirm the photoregulation mechanism postulated by Lovrien were continued. In 1977, Negishi et al. [6] found a pronounced photo-stimulated viscosity change of an aqueous solution of 2-hydroxyethyl methacrylate (HEMA) — A-vinylpyrrolidone (VPy) copolymer a and CHP or acid yellow 38 (2). The reduced viscosity reversibly decreased as much as 12%, as shown in Figure 3. The interaction between the polymer and CHP was sucessfully controlled by photoirradiation. The result suggested that the mechanism should strongly depend on the pair of polymer and dyes [7]. 

International Sorbent Technology, SBD-1 from J. T. Baker, and the Oasis HLB poly(divinylbenzene-co-A-vinylpyrrolidone) polymer of Waters. All of these polymers contain some trace of hydrophilic character to improve their wetting characteristics for good mass transfer, but yet the polymers still have high capacities for polar organic compounds. 

The Oasis HLB sorbent by Waters is a high-surface-area copolymer of [poly(divinylbenzene-co-A-vinylpyrrolidone)] (Fig. 12.4) that has the property of conditioning with only water. Methanol is not needed This is the only... 

A -Vinylpyrrolidone 1 (1.00 g, 9.0 mmol) was spread on cylindric glass rings (Raschig coils) in a 500-mL flask and crystallized by cooling to 0 °C in a vacuum. HBr gas (1 bar) was applied for 2h at that temperature. Excess gas was pumped off to a recipient at -196 °C for further use and the solid reaction product 2 was left at room temperature with repeated evacuation for removal of the liberated HBr. The racemic product 3 was recrystallized from acetone to yield 650 mg (65%) of the pure compound (mp 70-73 °C) that was spectroscopically characterized. 

The water content in the PMAA gel contributes to the segmental motion of the network polymer as described above. On the other hand, the restraint of chain mobility in poly(A-vinylpyrrolidone) gel, caused by the presence of crosslinking and entanglement of polymer chains, was identified [35]. The Ti for the PMAA in the gel was also measured as a function of the degree of crosslinking with constant water content. The Ti values obtained for the main and side chain carbons of the network polymer in the PMAA gel (q = 3.4), as a function of the mole ratio of MBAA to MAA (F) and uncrosslinked PMAA solution (29.4 w%), are plotted in Fig. 20.12(a, b). 

In 1996, a new hydrophilic-lipopophilic balance (HLB) adsorbent was introduced. Oasis HLB (Waters Corporation, Millford, MA). This macroporous copolymer (poly[divinylbenzene-co-A-vinylpyrrolidone]) exhibits hydrophilic and lipophilic retention characteristics, its major features being the abilities to remain wetted with water and to retain a wide spectrum of polar and nonpolar compounds, among which are OCPs. ... 

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