02166nas a2200241   4500008004100000022001400041245011300055210006900168260009900237300001600336490000700352520124300359653002501602653002301627653001501650100001701665700002301682700002501705700002801730700001501758700001901773856013201792       2005                        eng d  a0032-386100aSynthesis and swelling behaviour of hydrophobically modified responsive polymers in dilute aqueous solutions0 aSynthesis and swelling behaviour of hydrophobically modified res  aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLANDbELSEVIER SCI LTDcDEC  a12190-121990 v463 a<p>New series of associating polymers were synthesised in order to investigate opposite behaviours of hydrophobically modified water-soluble polymers and thermoresponsive water-soluble polymers carrying LCST stickers. On the basis of a poly(acrylic acid) backbone, amino-terminated poly(N-isopropylacrylamide), poly(ethylene oxide-co-propylene oxide) and/or dodecyl chains were grafted following a reaction of condensation activated by carbodiimide. Two homologous series of well-defined single grafted and double grafted copolymers were obtained, with double grafted chains containing both C12 and LCST grafts. The dilute solution properties of these copolymers were carefully studied by capillary viscometry. At low salt concentration and below the LCST of the grafts, the swelling properties of macromolecular chains are controlled either by intramolecular associations between hydrophobes, excluded volume effect exerted by hydrophilic grafts or by a balance between these opposite interactions. The deswelling of macromolecular chains, induced by hydrophobic interactions, is amplified at higher ionic strength and more particularly above the transition temperature of the side chains. (c) 2005 Elsevier Ltd. All rights reserved.</p>10aassociating polymers10apoly(acrylic acid)10aviscometry1 aIyer, N., P.1 aHourdet, Dominique1 aBadiger, Manohar, V.1 aChassenieux, Christophe1 aPerrin, P.1 aWadgaonkar, P.  uhttps://library.ncl.res.in/content/synthesis-and-swelling-behaviour-hydrophobically-modified-responsive-polymers-dilute-aqueous01761nas a2200181   4500008004100000022001400041245005500055210005500110260011000165300001400275490000700289520110400296100002301400700001801423700002801441700002101469856008901490       2010                        eng d  a1463-907600aStructure and gelation mechanism of silk hydrogels0 aStructure and gelation mechanism of silk hydrogels  aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcFEB  a3834-38440 v123 a<p>Silk fibroin was regenerated from cocoons produced by the silkworm Bombyx Mori. Light scattering showed that an aqueous solution of the regenerated silk fibroin (RSF) was made of individual proteins with a weight average molar mass of about 4 x 10(5) g mol(-1) and a hydrodynamic radius of about 10 nm. Gel formation of RSF in acidic solutions was investigated as a function of the pH (2-4), concentration (0.5-10 g L(-1)) and temperature (5-70 degrees C). The structure of the gels was studied using light scattering and confocal laser scanning microscopy. The structure was found to be self-similar from length scales of less than 15 nm up to length scales of about 1 mm, and characterized by a correlation length of a few microns. Gel formation was tracked using turbidity, rheology, light scattering and circular dichroism. Gelation involves the formation of self-similar aggregates with a growth rate that increases exponentially. The protein aggregation is correlated to, and perhaps caused by, the formation of beta-sheets, the fraction of which also increases exponentially with time.</p>1 aNagarkar, Shailesh1 aNicolai, Taco1 aChassenieux, Christophe1 aLele, Ashish, K.  uhttps://library.ncl.res.in/content/structure-and-gelation-mechanism-silk-hydrogels-0