01757nas a2200157 4500008004100000245005800041210005700099260000800156490000600164520124600170100001501416700002201431700002301453700003101476856009201507 2017 eng d00aSolution processed cellulose/melanin films and fibres0 aSolution processed cellulosemelanin films and fibres cJUN0 v53 aMelanins constitute a class of biomacromolecules that are abundant in nature. Although they exhibit a unique range of physical and chemical properties, their intractable nature has precluded their dissolution in common solvents and facile processing into functional materials. The authors found that commercially available 40 wt% tetrabutylammonium hydroxide (Tbah) solution could yield stable solutions of synthetic and natural melanins at ambient conditions and the dissolution rate could be accelerated by microwave radiation. Transmission electron microscopy images clearly show the disruption of the aggregated structure of melanins in Tbah. Scanning electron microscopy images of melanin/Tbah solutions precipitated in acetone revealed that melanins are dissolved and regenerated and not merely dispersed. To the best of the authors’ knowledge, this is the first report demonstrating a facile approach to solution processing melanins with other biopolymers, which allows leverage of many unique properties of melanins. As an illustrative example, the authors demonstrate here the successful fabrication of cellulose/melanin composite films and fibers and their significant dye absorption capacity (62% reduction) with methylene blue.1 aFarsa, Ram1 aPimpalkar, Nikhil1 aShete, Abhijit, P.1 aShanmuganathan, Kadhiravan uhttps://library.ncl.res.in/content/solution-processed-cellulosemelanin-films-and-fibres01840nas a2200277 4500008004100000022001400041245012000055210006900175260000900244300002600253490000800279520088000287653002401167653002301191653001801214653001801232653001701250653002301267100002201290700002001312700002201332700002201354700002601376700003101402856012901433 2019 eng d a0927-775700aSustained release insect repellent microcapsules using modified cellulose nanofibers (mCNF) as pickering emulsifier0 aSustained release insect repellent microcapsules using modified  cDEC  aArticle Number:1238830 v5823 a

We report here an approach to encapsulate N, N-diethyl-3-methylbenzamide (DEET), an insect repellent, through interfacial polycondensation using modified cellulose nanofiber (CNF) as pickering emulsifier. We found that stearic acid functionalized CNF (mCNF) can be used to form stable pickering emulsions (oil-in-oil and water-in-oil), and further encapsulate DEET using interfacial polycondensation with very high encapsulation efficiency of about 98%. Another major advantage of this approach is that mCNF can act both as pickering emulsifier and also strengthen the barrier properties of microcapsules resulting in significant reduction in release rate of DEET. Interpretation of the release profiles using standard mathematical models proposed by Ritger-Peppas show a factor of three reduction in release rate constant for the microcapsules reinforced with mCNF.

10aCellulose nanofiber10aControlled release10aMicrocapsules10aNanocomposite10ananoparticle10aPickering emulsion1 aKadam, Sandip, L.1 aYadav, Prashant1 aBhutkar, Siddhant1 aPatil, Vishal, D.1 aShukla, Parshuram, G.1 aShanmuganathan, Kadhiravan uhttps://library.ncl.res.in/content/sustained-release-insect-repellent-microcapsules-using-modified-cellulose-nanofibers-mcnf02508nas a2200253 4500008004100000022001400041245012300055210006900178260000800247300001100255490000700266520164100273653002201914653002601936653002101962653002601983653001302009653001602022100001902038700001802057700002402075700003102099856012402130 2023 eng d a0969-023900aSynthesis of N-oxyethylene substituted imidazolium-based zwitterions as a recyclable solvent for cellulose dissolution0 aSynthesis of Noxyethylene substituted imidazoliumbased zwitterio cJAN a87-1090 v303 a

Cellulose is a readily available, renewable, and natural biomaterial that has the potential to replace synthetic fibres. However, their processing to shaped materials such as fibre or film is still complex and restricted due to its insolubility in most conventional solvents. Herein, we present the synthesis and cellulose dissolution characteristics of a new class of recyclable zwitterions composed of tethered N-oxyethylene substituted imidazolium cation and alkyl carboxylate anion. Investigations on cellulose dissolution showed that increasing the alkyl chain length of carboxylate anion and introduction of oxyethylene unit on imidazolium ring led to better cellulose dissolution ability, and up to 12% (w/w) cellulose could be dissolved in aqueous zwitterions at 105 degrees C. The thermal behavior of zwitterions and their cellulose solutions was characterized by TGA and found to be more stable than the NMMO and Lyocell solutions. Rheological characterization of cellulose solutions revealed viscoelastic behavior and zero shear viscosity of 6-12% (w/w) cellulose solution in hexanoate containing aqueous zwitterion was 555 to 5900 Pa.s at 120 degrees C. The characteristics of cellulose solution indicate its potential for processing to cellulose fibre by extrusion through a tiny spinneret. Physico-chemical analysis of regenerated cellulose indicates that zwitterions cause no adverse effect on cellulose structure and morphology during dissolution. The zwitterions are recovered after the cellulose regeneration process, and the recovery was found to be 99.6% after purification using the ion-exchange method.

10aCarboxylate anion10aCellulose dissolution10aOxyethylene unit10aRegenerated cellulose10aRheology10azwitterions1 aJadhav, Sachin1 aGanvir, Vivek1 aSingh, Madan, Kumar1 aShanmuganathan, Kadhiravan uhttps://library.ncl.res.in/content/synthesis-n-oxyethylene-substituted-imidazolium-based-zwitterions-recyclable-solvent00811nas a2200217 4500008004100000022001400041245012800055210006900183260000900252490000800261653001400269653002300283653002400306100001900330700002100349700001900370700001800389700002400407700003100431856013100462 2025 eng d a0144-861700aStructure and properties of the cellulose fibres spun from imidazolium-based carboxylate functionalized zwitterionic liquid0 aStructure and properties of the cellulose fibres spun from imida cJAN 0 v34810acellulose10aDirect dissolution10aZwitterionic liquid1 aJadhav, Sachin1 aSingh, Dhirendra1 aGupta, Deepika1 aGanvir, Vivek1 aSingh, Madan, Kumar1 aShanmuganathan, Kadhiravan uhttps://library.ncl.res.in/content/structure-and-properties-cellulose-fibres-spun-imidazolium-based-carboxylate-functionalized02214nas a2200229 4500008004100000022001400041245010200055210006900157260000800226300001100234490000800245520141200253653003101665653002301696653001701719653002201736100002001758700002501778700002201803700003101825856012801856 2025 eng d a1381-514800aSustained release polyurethane microcapsules by interfacial polycondensation using aromatic diols0 aSustained release polyurethane microcapsules by interfacial poly cNOV a1064600 v2163 a

Polyurea-urethane (PUU) microcapsules prepared via interfacial polymerization have gained significant interest due to their tunable size and membrane thickness, high loading efficiency, and scalability. Although several aromatic and aliphatic diols and polyols have been used to produce PU foams and films, the use of aromatic diols to synthesize PUU MICs via interfacial polymerization is an unexplored domain due to the restricted solubility of aromatic diols in water. This report highlights the successful preparation of PUU microcapsules using an aromatic diol (benzene-1,4-dimethanol, BDM) to encapsulate dimethyl phthalate (DMP), a model insect repellent. The developed PUU microcapsules exhibited a high % encapsulation efficiency of 92 % and a size range of 1-20 mu m. Differential scanning calorimetry (DSC) thermograms revealed a significantly high glass transition temperature (Tg) of 143 degrees C as compared to 108 degrees C in the case of PUU MICs with aliphatic diols. Release studies confirm enhanced barrier properties for aromatic diol-based MICs as compared to aliphatic ethylene glycol-based PUU MICs, and interpretation of the release profile using the Weibull Model reveals that Fickian diffusion is the dominant mechanism in the release of DMP. These microcapsules can be used in high-performance applications such as composites, coatings, electronics, and construction.

10ainterfacial polymerization10aMicroencapsulation10apolyurethane10asustained release1 aYadav, Prashant1 aRavikumar, Aniruddha1 aAmbade, Ashootosh1 aShanmuganathan, Kadhiravan uhttps://library.ncl.res.in/content/sustained-release-polyurethane-microcapsules-interfacial-polycondensation-using-aromatic02056nas a2200241 4500008004100000022001400041245009200055210006900147260000800216300001400224490000700238520127500245653001601520653002801536653001401564653000901578100001801587700001601605700001901621700001901640700003101659856012401690 2026 eng d a0969-023900aSimple two-step gelation process to strengthen 3D printed carboxy methyl cellulose gels0 aSimple twostep gelation process to strengthen 3D printed carboxy cMAR a2015-20300 v333 a

Carboxymethyl cellulose (CMC) is a water-soluble cellulose ether that is widely utilized in hydrogel applications due to its exceptional water absorption and biocompatibility. This study reports a simple two step strategy to make mechanically robust CMC gels without any additional chemical crosslinkers and how it could be leveraged to strengthen 3D printed CMC gels. These hydrogels, prepared through acid-induced gelation followed by freeze-thawing, exhibited a compressive modulus of 12.4 +/- 0.92 kPa and a compressive strength of 491.0 +/- 18.1 kPa. They could be leveraged for strengthening 3D printing hydrogels of intricate shapes by direct ink writing. Small amplitude oscillatory shear (SAOS) tests indicated an order of magnitude higher storage modulus for freeze-thawed gels (FC) as compared to only acid-induced CMC gels (HCMC). Nonetheless, stress relaxation experiments revealed that FC, as well as HCMC gels, relax at similar time scales. FC gels exhibited clear birefringence under crossed polarizers, indicating molecular ordering that is consistent with the presence of ordered/crystalline domains. Such ordered domains likely contribute to the higher elastic modulus and compressive strength observed in FC gels as compared to HCMC gels.

10a3D printing10aCarboxymethyl cellulose10acellulose10aGels1 aRajput, Tejas1 aSathe, Asmi1 aGopal, Animesh1 aSharma, Aakash1 aShanmuganathan, Kadhiravan uhttps://library.ncl.res.in/content/simple-two-step-gelation-process-strengthen-3d-printed-carboxy-methyl-cellulose-gels