02097nas a2200265 4500008004100000022001400041245011800055210006900173260009900242300001200341490000700353520112100360653001701481653002001498653001801518653002101536653002601557653001301583100002501596700001601621700002601637700002101663700001701684856013001701 2010 eng d a0144-861700aFree radical graft copolymerization of N-vinyl-2-pyrrolidone onto k-carrageenan in aqueous media and applications0 aFree radical graft copolymerization of Nvinyl2pyrrolidone onto k aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLANDbELSEVIER SCI LTDcSEP a424-4310 v823 a

In the present article, the graft copolymer of k-carrageenan with N-vinyl-2-pyrrolidone (NVP) has been synthesized using PMS/maleic acid as a redox initiator in aqueous medium and reaction conditions have been optimized to obtain maximum % grafting ratio (%G). The optimum conditions of maximum grafting have been found by varying the different parameters. On increasing the concentration of maleic acid and peroxymonosulphate from 1.6 x 10(-3) to 4.8 x 10(-3) mol dm(-3) and 0.6 x 10(-2) to 2.2 x 10(-2) mol dm(-3) respectively, the initially grafting parameters increased and after a certain range of concentration grafting parameters showed decreasing trend. The small increment of concentration in hydrogen ion causes increment in percentage grafting. It was observed that the grafting parameters increase as the concentration of N-vinyl-2-pyrrolidone increases up to 16 x 10(-2) mol dm(-3) after that it decreased. The optimum condition for maximum grafting has obtained at concentration 1.0 g dm(-3) of k-carrageenan at 40 degrees C and 120 min, respectively. (C) 2010 Elsevier Ltd. All rights reserved.

10aflocculation10aGraft copolymer10ak-Carrageenan10aMetal ion uptake10aN-vinyl-2-pyrrolidone10aswelling1 aMishra, Madan, Mohan1 aSand, Arpit1 aMishra, Dinesh, Kumar1 aYadav, Mithilesh1 aBehari, Kunj uhttp://library.ncl.res.in/content/free-radical-graft-copolymerization-n-vinyl-2-pyrrolidone-k-carrageenan-aqueous-media-and-002195nas a2200241 4500008004100000022001400041245012300055210006900178260007600247300001400323490000800337520130900345653001701654653001701671653002001688653002101708653001301729100001601742700002101758700002601779700001701805856013101822 2011 eng d a0021-899500aAlginic acid-g-poly(N-vinylformamide) graft copolymer: synthesis, characerization, swelling, and flocculation property0 aAlginic acidgpolyNvinylformamide graft copolymer synthesis chara aCOMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USAbWILEY-BLACKWELLcAUG a1400-14070 v1213 a

The graft copolymer of N-vinylformamide with alginic acid was synthesized by free radical polymerization using potassium peroxymonosulphate and thiourea as redox pair in inert atmosphere. The optimum conditions for maximum grafting have been determined by varying the concentrations of N-vinylformamide, potassium peroxymonosulphate, thiourea, sulfuric acid, alginic acid as well as time duration and temperature. The grafting parameters increase up to the certain concentrations of N-vinylformamide, potassium peroxymonosulhate, thiourea, and hydrogen ion while thereafter grafting parameters decrease. The effect of alginic acid concentration on grafting parameters has been observed to decrease continuously. It has also been found that grafting parameters increase up to certain time and temperature, respectively, and thereafter decrease. The swelling properties of graft copolymer in terms of swelling ratio and percent swelling are investigated. Flocculation property of pure and grafted sample for both coking and noncoking coals is also investigated for the treatment of coal mine waste water. The graft copolymer has been characterized by Fourier transform infrared spectroscopy as well as thermogravimetic analysis. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci 121: 1400-1407, 2011

10aalginic acid10aflocculation10aGraft copolymer10aN-vinylformamide10aswelling1 aSand, Arpit1 aYadav, Mithilesh1 aMishra, Dinesh, Kumar1 aBehari, Kunj uhttp://library.ncl.res.in/content/alginic-acid-g-polyn-vinylformamide-graft-copolymer-synthesis-characerization-swelling-and-002012nas a2200241 4500008004100000022001400041245008600055210006900141260009000210300001000300490000700310520116100317653001401478653001201492653002001504653001901524653001901543653001701562653002201579100002201601700003201623856011501655 2012 eng d a0363-904500apH Sensitive graft copolymers for zero order drug release: a mechanistic analysis0 apH Sensitive graft copolymers for zero order drug release a mech aTELEPHONE HOUSE, 69-77 PAUL STREET, LONDON EC2A 4LQ, ENGLANDbINFORMA HEALTHCAREcJAN a73-830 v383 a

Aliphatic polyesters containing pendent unsaturation were synthesized by the polycondensation of a diol, dicarboxylic acid and glycidyl methacrylate. Grafting methacrylic acid (MAA) resulted in graft copolymers containing polyester backbone and MAA grafts. Depending on composition, the polymers swelled extensively and eroded or dissolved at near neutral pH but remained in collapsed state at acidic pH. Three representative drugs differing in solubility, viz., Diltiazem hydrochloride (DH), Indomethacin (IM) and Verapamil hydrochloride (VH) were released at constant rate from tablets made by compressing spray-dried microparticles. The release of DH at constant rate has been attributed to increase in diffusion coefficient of the drug from the swollen layer of matrix. The release of IM and VH at constant rate was governed by erosion and was enhanced in matrices which undergo dissolution. The release rate was enhanced with increasing MAA content and the frequency of grafts along the polyester backbone. Once a day dosage forms for drugs differing in solubility have been developed using a single polymer matrix which is easy to manufacture.

10aDiffusion10aerosion10aGraft copolymer10amatrix tablets10amicroparticles10aspray drying10asustained release1 aMuthusamy, Ramesh1 aKulkarni, Mohan, Gopalkrish uhttp://library.ncl.res.in/content/ph-sensitive-graft-copolymers-zero-order-drug-release-mechanistic-analysis-0