Polymer nitrile N-oxides directed toward catalyst- and solvent-free click grafting

Wang, Chen‐Gang; Koyama, Yasuhito; Yonekawa, Morio; Uchida, Satoshi; Takata, Toshikazu

doi:10.1039/c3cc42992j

Cited by 31 publications

(30 citation statements)

References 31 publications

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“…1,3-dipolar cycloaddition reaction between an organic Nitrile N-Oxides and an alkene resulting in the formation of isoxazoline is a versatile tool in polymer chemistry for realizing cross-linked networks [9,10]. Nitrile N-Oxide containing energetic RC NO structure is the more active 1,3-dipole than azide, which can react with the unsaturated bond at room temperature or lower temperature [11][12][13].…”

Section: Introductionmentioning

confidence: 99%

Hydroxyl‐terminated Polybutadiene Curing by 1,3‐dipolar Cycloaddition of Energetic Nitrile N‐Oxides: Room Temperature Curing Property, Kinetics, Thermodynamics, and Propellant Combustion Characteristics

Lei

Fan

Huo

2018

Propellants Explo Pyrotec

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5‐nitro‐1,3‐benzenedichloroaldehyde oxime was designed and synthesized to achieve room temperature curing of HTPB binders, and its structures were characterized. A new kind of 1,3‐dipolar cycloaddition reaction system was formed by HTPB as main resin, 5‐nitro‐1,3‐benzenedichloroaldehyde oxime and triethylamine as curing agent. The results revealed that the formation of isoxazoline ring in cured HTPB elastomers mainly derived form the reaction of Nitrile N‐Oxide with cis alkene of HTPB, and the cured HTPB elastomers underwent three stages decomposition. The kinetic parameters and thermodynamic parameters for the 14 % curing agent's sample were obtained from the DSC data. The activation energy was computed to be 204.75 kJ mol−1 and pre‐exponential factor was 1.38×1023 s−1.The burning rate of the propellant showed that the propellant with HTPB cured by containing −NO2 Nitrile N‐Oxides (100 % HTPB, 14 % Nitrile N‐Oxides, 2 % Aluminum and 77 % Ammonium perchlorate, Curing at 25 °C for 5 days ) had a higher burning rate and pressure exponent compared to conventional HTPB propellant (100 % HTPB, 14 % toluene diisocyanate, Nitrile N‐Oxides, 2 % Aluminum and 77 % Ammonium perchlorate, Curing at 60 °C for 5 days). Therefore, the containing −NO2 Nitrile N‐Oxides curing system could be used as a novel promising curing system for HTPB‐based solid composite propellants.

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Section: Introductionmentioning

confidence: 99%

Hydroxyl‐terminated Polybutadiene Curing by 1,3‐dipolar Cycloaddition of Energetic Nitrile N‐Oxides: Room Temperature Curing Property, Kinetics, Thermodynamics, and Propellant Combustion Characteristics

Lei

Fan

Huo

2018

Propellants Explo Pyrotec

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“…The utilization of functional monomers possessing clickable groups for polymer synthesis is an interesting approach for designing functional polymers. Several types of click reactions such as copper‐catalyzed azide‐alkyne cycloaddition (CuAAC), thiol‐ene, thiol‐yne, Michael thiol‐ene, Diels‐Alder, nucleophilic substitution on pentaflurophenyl ester group, [2 + 3] cycloaddition involving nitrile N‐oxide, and so forth have been exploited to synthesize chemically modified polyurethanes …”

Section: Introductionmentioning

confidence: 99%

Clickable polyurethanes based on s‐triazine ring containing aromatic diisocyanate bearing pendent alkyne group: Synthesis and postmodification

Garg

Chatterjee

Wadgaonkar

2017

J. Polym. Sci. Part A: Polym. Chem.

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A new s-triazine ring containing aromatic diisocyanate bearing a pendent alkyne group, namely, 2,4-bis(4-isocyanatophenoxy)26-(prop-2-yn-1-yloxy)21,3,5-triazine was synthesized and reacted with various diols viz., 1,10-decanediol, tetraethylene glycol and polyethylene glycols in the presence of dibutyltin dilaurate as the catalyst to obtain a series of linear polyurethanes. The selected polyurethanes possessing pendent alkyne groups were postmodified with chemically diverse azides viz., 1-(azidomethyl)benzene, 1-(azidomethyl)pyrene, and methoxy end-caped poly(ethylene glycol) azide via coppercatalysed azide-alkyne Huisgen 1,3-dipolar cycloaddition. FTIR and 1 H NMR spectra indicated quantitative click reaction. UVvis and fluorescence spectroscopic analysis confirmed complete incorporation of pyrenyl groups indicating the formation of fluorescence active polyurethane by postmodification with 1-(azidomethyl)pyrene. TG analysis of polyurethanes indicated two stage weight loss and their thermal stability, as judged by T 10 values, was governed by weight percent of urethane linkages. The water contact angle measurements revealed improved wettability with increased content of PEG either in the backbone of polyurethanes or as grafted chains. DLS and TEM studies confirmed that certain polyurethanes possessing PEG segments displayed self-assembly in aqueous solution, which was further supported by pyrene encapsulation studies using UV-vis spectroscopy.

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“…25 The identi¯ed weak peaks at 2289 cm À1 and 1202 cm À1 correspond to the C-N stretching vibration. 26 The peak at 1651 cm À1 belongs to the PDR stretch of the carboxylic (ÀC¼O) group. 27 The peak at 1589 cm À1 is based on the N-H stretching of primary amide, 28 which indicates the existence of the amino groups.…”

Section: -5mentioning

confidence: 99%

Two Types of Immunoassay Based on Nile Blue Labeling Polydopamine Nanospheres

Liu

et al. 2017

NANO

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The sandwich-type immunoassays have been developed by using electrochemical and surfaceenhanced Raman scattering (SERS) techniques for the detection of carcinoembryonic antigen (CEA). Nile blue as a kind of Raman dye has been decorated on nanospheres with polydopamine resin (PDR) via -stacking interaction. The Nile blue displays the strong SERS signals as well as a characteristic electrochemical reduction peak at À0.33 V (versus Ag/AgCl). The implementation of the PDR nanospheres mixing with Au nanoparticles (AuNPs/PDR) exhibits a better electrical conductivity and large SERS enhancement. The immunoassays based on Nile bluelabeled AuNPs/PDR nanospheres have been fabricated by using electrochemical and SERS techniques for the detection of CEA. The proposed immunoassay shows higher sensitivity, high selectivity, lower detection limit and long-term stability. The performances of the electrochemical immunoassay are better than that of SERS immunoassay. For the electrochemical immunoassay, the linear range occurs from 1 pg/mL to 100 ng/mL (R ¼ 0:995) with a detection limit of 0.68 pg/ mL and signal-to-noise ratio of 3 in the detection of CEA. The data for the analysis of human serum samples by using the electrochemical method are acceptably consistent with those obtained from the enzyme-linked immunosorbent assay (ELISA). The proposed immunoassay exhibits a promising potential for application in clinical diagnosis.

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Polymer nitrile N-oxides directed toward catalyst- and solvent-free click grafting

Cited by 31 publications

References 31 publications

Hydroxyl‐terminated Polybutadiene Curing by 1,3‐dipolar Cycloaddition of Energetic Nitrile N‐Oxides: Room Temperature Curing Property, Kinetics, Thermodynamics, and Propellant Combustion Characteristics

Hydroxyl‐terminated Polybutadiene Curing by 1,3‐dipolar Cycloaddition of Energetic Nitrile N‐Oxides: Room Temperature Curing Property, Kinetics, Thermodynamics, and Propellant Combustion Characteristics

Clickable polyurethanes based on s‐triazine ring containing aromatic diisocyanate bearing pendent alkyne group: Synthesis and postmodification

Two Types of Immunoassay Based on Nile Blue Labeling Polydopamine Nanospheres

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