01561nas a2200145 4500008004100000245009600041210006900137260000800206490000600214520099000220100002601210700002401236700003001260856012501290 2020 eng d00aIsothermal cold crystallization kinetics of borassus powder/poly(lactic acid) biocomposites0 aIsothermal cold crystallization kinetics of borassus powderpolyl cFEB0 v33 a

Poly(lactic acid) (PLA) is an important bioplastic which is semicrystalline with very slow crystallization rate. Therefore, the processed PLA products are usually amorphous and transparent with low mechanical properties. Currently, research efforts are focused on enhancing the crystallization rate of PLA. In this work, natural borassus fibers are incorporated into PLA and the isothermal cold crystallization kinetics is investigated using differential scanning calorimetry and Avrami equation. The isothermal cold crystallization studies revealed that, the relative crystallinity increases with the increasing content of borassus. The Avrami exponent “n” was determined ~2.0 indicated the one‐dimensional crystal growth with rod‐like geometry. The overall crystallization rate increased due to the borassus content and was expressed by crystallization halftime (t1/2). This study clearly showed that borassus fibers act as nucleating agent.

1 aMarathe, Yogesh, Nana1 aChellaswamy, Ramesh1 aBadiger, Manohar, Virupax uhttps://library.ncl.res.in/content/isothermal-cold-crystallization-kinetics-borassus-powderpolylactic-acid-biocomposites01933nas a2200253 4500008004100000022001400041245014900055210006900204260000800273300001200281490000700293520097800300653002501278653003801303653002601341653001301367653002301380653003001403100001701433700003001450700004301480700002601523856013001549 2022 eng d a0959-810300aInvestigation of domain structures in monomethoxy poly(ethylene glycol)-b-poly(caprolactone) grafted poly(acrylic acid) by NMR diffusion studies0 aInvestigation of domain structures in monomethoxy polyethylene g cAUG a976-9840 v713 a

Associating polymers developed by grafting a block copolymer of monomethoxy poly(ethylene glycol)-b-poly(caprolactone) (MPEG-b-PCL) onto poly(acrylic acid) undergo an irreversible sol-gel transition on heating. The influence of various physicochemical parameters on the thermoresponsive behaviour was examined by rheology and NMR studies. Pulsed field gradient NMR diffusion studies were performed to probe the mechanism of thermally induced gelation. Analysis of the diffusion data reveals the presence of loosely and strongly associated structures which respond differently to variation in temperature. It is observed that the polymer solution, which is visibly homogeneous, is heterogeneous on a mesoscopic scale with a distribution of domains. Detailed investigation of the thermally induced sol-gel transition shows that the mechanism of gelation involves irreversible alterations in the domain structure and size. (c) 2022 Society of Industrial Chemistry.

10aassociating polymers10ahydrophobically modified polymers10aNMR diffusion studies10aRheology10asol-gel transition10athermoresponsive polymers1 aTiwari, Neha1 aBadiger, Manohar, Virupax1 aRajamohanan, Pattuparambil, Ramanpilla1 aRavindranathan, Sapna uhttps://library.ncl.res.in/content/investigation-domain-structures-monomethoxy-polyethylene-glycol-b-polycaprolactone-grafted