01840nas 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-mcnf01772nas a2200265 4500008004100000022001400041245007500055210006900130260000900199300001400208490000700222520099600229653000801225653001601233653001401249653002001263653000901283100001901292700001701311700001501328700002001343700001701363700001901380856010701399 2020 eng d a1861-472800aAmidinato germylene-zinc complexes: synthesis, bonding, and reactivity0 aAmidinato germylenezinc complexes synthesis bonding and reactivi cOCT  a3116-31210 v153 a

Despite the explosive growth of germylene compounds as ligands in transition metal complexes, there is a modicum of precedence for the germylene zinc complexes. In this work, the synthesis and characterization of new germylene zinc complexes [PhC(NtBu)(2)Ge{N(SiMe3)(2)}-> ZnX2](2)(X= Br (2) and I (3)) supported by (benz)-amidinato germylene ligands are reported. The solid-state structures of2and3have been validated by single-crystal X-ray diffraction studies, which revealed the dimeric nature of the complexes, with distorted tetrahedral geometries around the Ge and Zn center. DFT calculations reveal that the Ge-Zn bonds in2and3are dative in nature. The reaction of2with elemental sulfur resulted in the first structurally characterized germathione stabilized ZnBr(2)complexes PhC(NtBu)(2)Ge(=S){N(SiMe3)(2)}-> ZnBr2(5). Therefore, the Ge=S in5is in-between Ge-S single and Ge=S double bond length, owing to the coordination of a sulfur lone pair of electrons to ZnBr2.

10aDFT10aGermathione10aGermylene10aX-ray Structure10azinc1 aYadav, Sandeep1 aKumar, Rohit1 aRaj, Vipin1 aYadav, Prashant1 aVanka, Kumar1 aSen, Sakya, S. uhttps://library.ncl.res.in/content/amidinato-germylene-zinc-complexes-synthesis-bonding-and-reactivity02205nas a2200289 4500008004100000022001400041245008700055210006900142260000800211300001100219490000800230520126600238653001601504653001301520653003101533653001701564653003601581653003301617100002001650700002101670700002001691700002101711700001801732700001701750700003101767856011701798 2020 eng d a0927-775700aDual responsive cellulose microspheres with high solid-state fluorescence emission0 aDual responsive cellulose microspheres with high solidstate fluo cAPR a1245100 v5913 a

Materials that respond to multiple stimuli such as magnetic field and light are attractive for security and medical diagnostic applications. One of the major challenges in dual functional microspheres is that the presence of magnetic nanoparticles can quench fluorescence emission. Also, there is a probability of solid-state quenching due to the proximity of the fluorophore. We report here a facile approach to prepare cellulose microspheres with high solid-state fluorescence using 40 % tetrabutylammonium hydroxide (TBAH). The fluorescence quenching effect due to the presence of Fe3O4 nanoparticles and solid-state quenching due to aggregation of fluorophore was systematically investigated. Microspheres with the detectable magnetic response and fluorescence quantum yield as high as 0.57 (FMB 414) was obtained by optimizing the reaction conditions. Such a high quantum yield has not been reported before for dual stimuli-responsive fluorescent microspheres. The magnetic and fluorescent properties were found to be durable even after multiple washing cycles. These dual responsive cellulose microspheres can be added as security features to authenticate documents such as passports, degree certificates, currency notes, financial documents etc.

10aFluorescent10aMagnetic10aMicrocrystalline cellulose10amicrospheres10aStimuli responsive microspheres10aTetrabutylammonium hydroxide1 aYadav, Prashant1 aPrajitha, K., P.1 aDhaware, Vinita1 aSubramani, Mohan1 aJoy, Pattayil1 aAsha, S., K.1 aShanmuganathan, Kadhiravan uhttps://library.ncl.res.in/content/dual-responsive-cellulose-microspheres-high-solid-state-fluorescence-emission01762nas a2200169 4500008004100000022001400041245009600055210006900151260000800220300001600228490000700244520115100251100001501402700002001417700003101437856012401468 2022 eng d a0022-246100aNanocellulose/melanin-based composites for energy, environment, and biological applications0 aNanocellulosemelaninbased composites for energy environment and  cAUG a14188-142160 v573 a

Melanins, a class of brown-black pigments present in many natural sources, exhibit unique physical and chemical properties such as photoprotection, photoconductivity, metal ion chelation, free radical quenching, proton conductivity, and significant antimicrobial properties. These properties could be leveraged in various environmental and energy applications. However, their limited solubility makes them less amenable to processing. Over the last decade, there has been tremendous interest in developing synthetic analogs of melanin that are easy to dissolve and process. Nonetheless, melanins or their synthetic analogs cannot form mechanically robust free-standing films and fibers. This drawback could be partly circumvented by creating composites of melanin with nanocellulose, a nanomaterial derived from cellulosic biomass. Composites of melanins and nanocellulose offer an opportunity to utilize the functional aspects of melanin-like polymers in a mechanically stable nanocellulose network. This review attempts to capture the recent developments on this topic with special emphasis on technologically relevant applications.

1 aRam, Farsa1 aYadav, Prashant1 aShanmuganathan, Kadhiravan uhttps://library.ncl.res.in/content/nanocellulosemelanin-based-composites-energy-environment-and-biological-applications02309nas a2200313 4500008004100000022001400041245009600055210006900151260000800220300001400228490000700242520130500249653001601554653001401570653001701584653001801601653002201619653001401641100003101655700002001686700002601706700001701732700002301749700001901772700002001791700002901811700003101840856012401871 2023 eng d a0032-388800aLuminescent 3D printed poly(lactic acid) nanocomposites with enhanced mechanical properties0 aLuminescent 3D printed polylactic acid nanocomposites with enhan cJUL a2059-20720 v633 a

The three-dimensional (3D) printing of functional composite materials has gained tremendous interest in recent years. Nevertheless, research on 3D printing of luminescent composite materials is very limited, and the mechanical properties of such 3D-printed composites are poor. Herein, we report the preparation and characterization of a poly(lactic acid) (PLA) composite that, when 3D printed, exhibits enhanced toughness and high solid-state fluorescence quantum yield. Incorporation of only 1 wt% pyrene butyric acid modified cellulose nanofibers (PBA-m-CNF) and l0 wt% thermoplastic polyurethane (TPU) into PLA led to 223% increase in toughness and 21% increase in tensile modulus of PLA. Scanning electron microscopy (SEM) and X-ray microcomputed tomography (mu-CT) analysis of the fractured cross-sections of 3D printed composites revealed a ductile failure mode. The PLA/PBA-m-CNF1/TPU10 3D printed composite also exhibited a high solid-state fluorescence quantum yield of 38.35%. To the best of our knowledge, this is the first report to show both enhanced mechanical properties and high solid-state fluorescence emission for 3D printable PLA. Such functional PLA composites could have potential applications in the fabrication of complex-shaped sensors, optical light pipes, etc.

10a3D printing10aComposite10afluorescence10aNanocellulose10apoly(lactic acid)10atoughness1 aKothavade, Premkumar, Anil1 aYadav, Prashant1 aNidhankar, Aakash, D.1 aTorris, Arun1 aPol, Harshawardhan1 aKafi, Abdullah1 aBateman, Stuart1 aSukumaran, Santosh, Babu1 aShanmuganathan, Kadhiravan uhttps://library.ncl.res.in/content/luminescent-3d-printed-polylactic-acid-nanocomposites-enhanced-mechanical-properties02487nas a2200277 4500008004100000022001400041245012500055210006900180260000900249300001400258490000600272520153800278653002001816653002001836653003501856653002101891653001401912100002501926700002001951700001901971700002301990700001902013700002002032700003102052856012602083 2024 eng d a2637-610500aEnhancing the crystallization kinetics and mechanical properties of poly(lactic acid) blends for 3D printing application0 aEnhancing the crystallization kinetics and mechanical properties cMAY  a5754-57620 v63 a

3D printing of poly(lactic acid) (PLA) blends has been attempted to resolve issues such as inherent brittleness and slow crystallization rate of PLA. However, a persistent challenge remains in the form of phase separation or gradual migration of the blended soft polymer or plasticizers. To simultaneously enhance the miscibility of the blends and toughness of 3D-printed parts, a triblock copolymer PLA-PEG-PLA was synthesized and blended with PLA in varying proportions (5, 10, 15, and 20 wt %). Blending only 10-20 wt % low molecular weight PLA-PEG-PLA into PLA yielded a miscible blend that showed a 45-fold increase in elongation at break and a 23-fold enhancement in toughness over neat PLA. Scanning electron microscopy (SEM) images of fractured cross sections revealed a brittle to ductile transition in 3D-printed PLA/PLA-PEG-PLA samples. Isothermal crystallization studies and data analysis using the Avrami equation showed an enhancement in the crystal growth rate and overall rate of crystallization. The blends achieved half of their crystallinity in approximately 3 min, a significant improvement over the 9 min required by PLA alone. This underscores the efficiency of our approach. This was also evident in the spherulite growth of 3D-printed PLA and mPLA blends when examined using polarized optical microscopy (POM). To the best of our knowledge, this is the first report exploring the use of blends that include PLA and low molecular weight PLA-PEG-PLA triblock copolymers for 3D printing applications.

10aCrystallization10aFFF 3D printing10aPLA-PEG-PLA triblock copolymer10apoly(lacticacid)10atoughness1 aKothavade, Premkumar1 aYadav, Prashant1 aGopal, Animesh1 aPol, Harshawardhan1 aKafi, Abdullah1 aBateman, Stuart1 aShanmuganathan, Kadhiravan uhttps://library.ncl.res.in/content/enhancing-crystallization-kinetics-and-mechanical-properties-polylactic-acid-blends-3d02343nas a2200277 4500008004100000022001400041245015600055210006900211260000900280300001400289490000700303520134000310653005801650653002101708653002801729653002601757653001701783100001701800700002001817700001901837700001801856700001801874700003101892700002001923856012201943 2025 eng d a1060-132500aAn improved one-pot synthesis of polydichlorophosphazene from ammonium sulfate and phosphorus pentachloride and assessment of its stability in solution0 aimproved onepot synthesis of polydichlorophosphazene from ammoni cNOV  a1016-10260 v623 a

Polyphosphazenes, with their synthetic flexibilities, can be tailored to achieve various desirable properties. The synthesis of basic linear polymer polydichlorophosphazene (PDCP) free of branching and crosslinking is the most challenging step, and its extreme sensitivity to moisture makes storage and handling difficult. In the reaction of (NH4)2SO4and PCl5 (1:4.5 mole ratio) via one-pot two-step method, the monomer [Cl3PNP(O)Cl2] synthesized from the 1st step directly undergoes bulk polycondensation (2nd step) to produce PDCP. Due to impurities, the produced PDCP is afflicted by frequent branching, cyclic oligomers, and crosslinking. We are reporting an improved one-pot synthesis coupled with an in-situ purification step of the monomer (as confirmed by 31P NMR) with little excess PCl5 in mole ratio (1:4.6-1:4.8). Further, the stability of PDCP and its solutions in toluene and THF have been examined under an inert atmosphere at three different temperatures: room temperature, 0 degrees C-4 degrees C, and -25 degrees C. These stored samples were monitored for cross-linking, gelling, or any other degradation by characterizing through 31P NMR for the appearance of additional peaks. The PDCP can be stored at -25 degrees C for 2 months (pure) and 4 months (toluene) without any deterioration in its structure.

10aP-trichloro-N-(dichloromonophosphoryl)monophosphazene10aPolycondensation10aPolydichlorophosphazene10astability in solution10astorage life1 aYadav, Abhay1 aYadav, Prashant1 aNewale, S., P.1 aSrivastav, V.1 aSingh, A., P.1 aShanmuganathan, Kadhiravan1 aSikder, Nirmala uhttps://library.ncl.res.in/content/improved-one-pot-synthesis-polydichlorophosphazene-ammonium-sulfate-and-phosphorus02214nas 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-aromatic