01728nas a2200277 4500008004100000022001400041245009200055210006900147260000800216300001200224490000700236520085900243653002001102653001401122653001701136653000801153653001301161100002001174700002301194700001801217700002801235700001701263700002601280700002301306856012101329 2021 eng d a2062-249X00aDesign and scale-up of continuous di-nitration reaction using pinched tube flow reactor0 aDesign and scaleup of continuous dinitration reaction using pinc cSEP a611-6240 v113 aScale-up of the di-nitration reaction for synthesis of selective herbicide pendimethalin using only nitric acid in continuous flow is presented in this work. This work showcases an approach for smooth scale-up for an herbicide for a production capacity of 50 kg/day using a pinched tube reactor. The approach begins with the batch experiments followed by flow synthesis using a 1/8-inchSS316 helical coil tube where kinetics of the di-nitration was determined, and process optimization was done. Systematic approach was followed for quantification of heat transfer, mass transfer and residence time distribution and scale-up. Detailed scale-up methodology is presented with effect of relevant parameters for successful scale-up. Modular pilot plant with inline quenching, extraction and separation are some of the salient features presented in this work.10acontinuous flow10anitration10aPinched tube10aRTD10ascale-up1 aHussain, Arshad1 aSharma, Mrityunjay1 aPatil, Suneha1 aAcharya, Roopashree, B.1 aKute, Mahesh1 aWaghchaure, Aishwarya1 aKulkarni, Amol, A. uhttps://library.ncl.res.in/content/design-and-scale-continuous-di-nitration-reaction-using-pinched-tube-flow-reactor01964nas a2200181 4500008004100000022001400041245014500055210006900200260000900269300001200278490000600290520127700296100002201573700001801595700001701613700002301630856012901653 2021 eng d a2516-023000aInkjet printing of silver nanowires on flexible surfaces and methodologies to improve the conductivity and stability of the printed patterns0 aInkjet printing of silver nanowires on flexible surfaces and met cJAN  a240-2480 v33 a

Silver nanowires (AgNWs) are known to be used for printing on rigid as well as flexible surfaces. Here we have developed a systematic approach for using AgNWs synthesized by the polyol method for printing on flexible surfaces using a simple inkjet printing method. Optimized ink formulation used in this work comprises a mixture of Ag NWs suspended in ethylene glycol directly taken after synthesis and isopropyl alcohol. Using such formulation saves time and loss of material while transferring to other solvents, which is the usual practice. The printed patterns demonstrate high conductivity and stability over many months, which can revolutionize the applications of functional nanomaterials in low-cost printed electronics. The importance of fragmentation of nanowires only to achieve specific aspect ratios, to facilitate easy jetting and to prevent clogging is demonstrated. Varied concentrations (10 mg mL(-1) to 50 mg mL(-1)) of Ag NWs are used in ink formulations in order to print highly conductive patterns (resistance < 50 Omega sq(-1)) in a minimal number of passes. The same composition was also seen to facilitate simple and time-efficient nano-welding at room temperature, which improves the conductivity and stability of the printed patterns.

1 aPatil, Prathamesh1 aPatil, Suneha1 aKate, Prachi1 aKulkarni, Amol, A. uhttps://library.ncl.res.in/content/inkjet-printing-silver-nanowires-flexible-surfaces-and-methodologies-improve-conductivity02210nas a2200253 4500008004100000022001400041245008500055210006900140260000800209300001100217490000800228520140200236653002001638653001101658653001501669653002201684653002601706653002101732100001801753700002101771700002701792700002301819856011401842 2021 eng d a1385-894700aQuantitative understanding of nucleation and growth kinetics of silver nanowires0 aQuantitative understanding of nucleation and growth kinetics of  cJUN a1287110 v4143 a

We have demonstrated that using polyol synthesis, it is possible to prepare high aspect ratio silver nanowires by controlling the experiments for process related issues which are usually ignored, viz. the overhead space in the batch reactor. It is found that by controlling the presence/absence of NOx gases with refluxing of nitric acid in the batch reactor with an overhead space of 80% volume, near complete conversion (-99%) of high aspect ratio NWs (-1000) can be attained. We provide a detailed understanding of other factors assisting in rapid polyol synthesis like temperature, stirring rate, Chloride ion concentration, optimal PVP weight ratios and PVP/AgNO3 ratio that can lead to high aspect ratio NWs. Besides the process parameters and reagent concentration effects, kinetic studies based on our nucleation and R-C Model evaluate the overall reaction rate constants for silver nanowires and the JMAK approach is used to theoretically validate our experimental results of the reactor headspace having strongest effect on the aspect ratios. Our study highlights the importance of various complications in the polyol synthesis, through detailed kinetic modelling and affixes values of temperature, reactor headspace, stirring rate and residence time in order to achieve reproducible synthesis of nanowires with complete conversion along with a method to separate these nanowires.

10aConducting inks10agrowth10aNucleation10aReaction kinetics10aRedox-crystallization10aSilver Nanowires1 aPatil, Suneha1 aKate, Prachi, R.1 aDeshpande, Jaydeep, B.1 aKulkarni, Amol, A. uhttps://library.ncl.res.in/content/quantitative-understanding-nucleation-and-growth-kinetics-silver-nanowires03504nas a2200253 4500008004100000022001400041245018200055210006900237260000800306300001600314490000700330520257000337100002302907700002502930700002902955700001602984700001803000700002503018700001703043700002303060700001903083700001703102856013103119 2022 eng d a2050-752600aDirect (hetero)arylation (DHAP) polymerization of conjugated polymers - new A-B-A monomer design for P(NDI2OD-T2) & the challenges of adopting DHAP for continuous flow processes0 aDirect heteroarylation DHAP polymerization of conjugated polymer cSEP a13025-130390 v103 a

P(NDI2OD-T2), also known as Polyera ActivInk N2200, was synthesized by the atom-economic direct hetero arylation polymerization (DHAP) route using a newly designed A-B-A monomer. The new monomer design involved flanking naphthalene diimide with bithiophene units in the bay position, which was further polymerized with bay substituted 1,4-dibromo naphthalene diimide, to afford the same polymer structure as P(NDI2OD-T2). The new monomer design resulted in a very high molecular weight (M-n: 99.5 kDa, D-M: 2.8) defect-free polymer in a quantitative yield by the DHAP batch process using 1,2,4-trichlorobenzene (TCB) as the solvent. DFT studies revealed that the abstraction of the alpha-proton from the naphthalene diimide substituted 2,2 `-bithiophene was favorable by 2.6 kcal mol(-1) (Delta Delta G) as compared to that from 2,2 `-bithiophene. The reason for this improved C-H activation at the alpha position can be attributed to the presence of C-HMIDLINE HORIZONTAL ELLIPSIS pi stabilizing interactions in naphthalene diimide substituted 2,2 `-bithiophene, which strengthens upon the extended charge delocalization throughout the ring, thus stabilizing the conjugate base generated after the proton abstraction. Continuous flow polymerization was carried out by pumping the DHAP reaction mixture including the monomers, catalyst, and additive (pivalic acid) solubilized in degassed TCB through a pre-heated glass condenser packed with K2CO3 and Celite under aerobic conditions. Reproducible molecular weights of M-n: 29.5 kDa, D-M: 1.7 were obtained at much lower concentrations of reactant mixture compared to that for batch polymerization. This is the first report of the synthesis of P(NDI2OD-T2) by a Continuous Flow Process adopting the DHAP route to obtain a defect-free polymer with reasonable molecular weights. P(NDI2OD-T2) was also synthesized by Stille polymerization as a reference control sample to compare the thermal and charge carrier transport properties of the DHAP polymers. Organic field-effect (OFET) mobility measurements indicated mobility values in the order of 10(-3) cm(2) V-1 s(-1) for the DHAP batch polymer (using the novel monomer design). The P(NDI2OD-T2) synthesized by DHAP batch using the commonly used starting materials - bisbromo naphthalene diimide and bithiophene, exhibited OFET mobilities which were one order less, similar to 10(-4) cm(2) V-1 s(-1). This observation highlights the importance of structural design in the monomer to enhance reactivity and thereby the bulk properties using the DHAP route.

1 aKakde, Navnath, R.1 aBharathkumar, H., J.1 aWavhal, Bhaiyyasaheb, A.1 aNikam, Arun1 aPatil, Suneha1 aDash, Soumya, Ranjan1 aVanka, Kumar1 aKrishnamoorthy, K.1 aKulkarni, Amol1 aAsha, S., K. uhttps://library.ncl.res.in/content/direct-heteroarylation-dhap-polymerization-conjugated-polymers-new-b-monomer-design-pndi2od01882nas a2200169 4500008004100000022001400041245010900055210006900164260000900233300001600242490000700258520125100265100002501516700001801541700002301559856013001582 2023 eng d a0888-588500aUnderstanding the nucleation and growth kinetics of the microwave-assisted synthesis of silver nanowires0 aUnderstanding the nucleation and growth kinetics of the microwav cSEP  a14199-142110 v623 a

Here, we present a detailed study of understanding the nucleation and growth kinetics of silver nanowire synthesis under microwave irradiation. The approach includes studying the effect of various parameters (viz., microwave power, reaction temperature, reaction time, substrate concentration, etc.) on the rate of nucleation and growth, as well as on the yield and morphology of silver nanowires. It is found that microwave power is the most important factor in leading to almost complete conversion of the substrate along with high aspect ratio nanowires in a short reaction time. Based on the observations, here, we have proposed a three-step growth kinetics mechanism for the synthesis of silver nanowires under the influence of microwaves. The approach comprises the autocatalytic growth of stable multiple twin particles after the nucleation process and their unidirectional growth to form nanowires. The FW autocatalytic model and the JMAK Avrami model were used to validate the proposed mechanism of AgNW formation based on our experimental results. The model predictions match very well with the conversion and yield of AgNWs. At the optimized conditions, wires with a 42 nm diameter and 94% yield were achieved within 4 min.

1 aSonawane, Jayesh, R.1 aPatil, Suneha1 aKulkarni, Amol, A. uhttps://library.ncl.res.in/content/understanding-nucleation-and-growth-kinetics-microwave-assisted-synthesis-silver-nanowires