@article { ISI:000283805600011,
	title = {Synthesis and characterization of thermo-sensitive graft copolymer of carboxymethyl guar and poly(N-isopropylacrylamide)},
	journal = {Carbohydrate Polymers},
	volume = {83},
	number = {1},
	year = {2011},
	month = {JAN},
	pages = {74-80},
	publisher = {ELSEVIER SCI LTD},
	address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND},
	abstract = {<p>Thermo-responsive graft copolymers of carboxymethyl guar [CMG] and semitelechelic poly(N-isopropylacrylamide) [PNIPAm] were synthesized by coupling reaction between them using a water-soluble coupling agent namely, 1-(3-(dimethylamino) propyl)-3-ethyl carbodiimide hydrochloride [EDC]. The incorporation of PNIPAm into CMG was confirmed by FT-IR and NMR spectroscopy. The graft copolymers, CMG-g-PNIPAm showed enhanced viscosity as compared to the unmodified CMG in the semi-dilute regime. Due to the presence of a LCST side chains [PNIPAm], the graft copolymers exhibited thermo-responsive nature with respect to temperature which was investigated using pyrene fluorescence probe studies. Although the thermo-responsive property was observed, the thermo-thickening behavior was not seen in these polymers. The graft copolymers in the semi-dilute regime (C(p) approximate to 10-20 g/L) showed viscoelastic properties and the relaxation time, tau, could be obtained from the crossover of frequency (oh) of storage modulus (G{\textquoteright}) and loss modulus (G {\textquoteleft}{\textquoteright}) in the oscillatory experiments. The activation energy {\textquoteleft}E(a){\textquoteright} of associations was investigated using the time temperature superpsition (TTS). These thermo-responsive polymers along with the biodegradability of CMG can have potential application as industrial thickening agent. (C) 2010 Elsevier Ltd. All rights reserved.</p>},
	keywords = {Carboxymethyl guar, Poly(N-isopropylacrylamide), Thermo-sensitivity and graft copolymer},
	issn = {0144-8617},
	doi = {10.1016/j.carbpol.2010.07.023},
	author = {Gupta, Nivika R. and Ghute, Pallavi P. and Badiger, Manohar V.}
}
