Journal articles: 'Alkyl amine based naphthoxazine'

1

Uyar, Tamer, Zeynep Koyuncu, Hatsuo Ishida, and Jale Hacaloglu. "Polymerisation and degradation of an aromatic amine-based naphthoxazine." Polymer Degradation and Stability 93, no. 12 (December 2008): 2096–103. http://dx.doi.org/10.1016/j.polymdegradstab.2008.09.003.

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Asadov, Z. H., S. M. Nasibova, T. A. Poladova, R. A. Rahimov, and A. Z. Asadova. "Petroleum collecting and petroleum dispersing reagents based on alkyl amine and alkyl iodides." Materials Research Innovations 16, no. 3 (June 2012): 175–78. http://dx.doi.org/10.1179/1433075x11y.0000000055.

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Zhang, Guanran, Alex S. Loch, Jos C. M. Kistemaker, Paul L. Burn, and Paul E. Shaw. "Dicyanovinyl-based fluorescent sensors for dual mechanism amine sensing." Journal of Materials Chemistry C 8, no. 39 (2020): 13723–32. http://dx.doi.org/10.1039/d0tc03974h.

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Wang, Chen, Na Wu, Daniel L. Jacobs, Miao Xu, Xiaomei Yang, and Ling Zang. "Discrimination of alkyl and aromatic amine vapors using TTF–TCNQ based chemiresistive sensors." Chemical Communications 53, no. 6 (2017): 1132–35. http://dx.doi.org/10.1039/c6cc08237h.

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Ishida, Hatsuo, and Daniel P. Sanders. "Regioselectivity and Network Structure of Difunctional Alkyl-Substituted Aromatic Amine-Based Polybenzoxazines." Macromolecules 33, no. 22 (October 2000): 8149–57. http://dx.doi.org/10.1021/ma991836t.

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Muchan, Pailin, Jessica Narku-Tetteh, Teeradet Supap, and Raphael Idem. "Amine Structure-Foam Behavior Relationship and Its Predictive Foam Model Used for Amine Selection for Design of Amine-based Carbon Dioxide (CO2) Capture Process." Current Chinese Science 1, no. 1 (December 23, 2020): 43–57. http://dx.doi.org/10.2174/2210298101999201002094601.

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Background: The use of an amine solution to capture CO2 from flue gases is one of the methods applied commercially to clean up the exhaust gas stream of a power plant. One of the issues in this process is foaming which should be known in order to select a suitable amine for design. Objectives: In this work, all possible types of amines used for CO2 capture, namely, alkanolamines, sterically hindered alkanolamines, multi-alkylamines and cyclic amines, were investigated to elucidate their chemical structure–foaming relationships. Methods: Foam volume produced by each type of 2M amine solution with its equilibrium CO2 loading was measured at 40°C using 94 mL/min of N2 flow. Results: Amines with a higher number or a longer chain of the alkyl group exhibited higher foam volume because of alkyl group’s ability to decrease the surface tension while increasing the viscosity of the solution. An increase in the number of hydroxyl or amino groups in the amine led to the reduction of foam formation due to the increase in surface tension and a decrease in viscosity of the solution. The predictive foam models for non-cyclic and cyclic-amines developed based on the structural variations, surface tension and viscosity of 29 amines predicted the foam volume very well with average absolute deviations (AAD) of 12.7 and 0.001%, respectively. The model accurately predicted the foam volume of BDEA, which was not used in model development with 13.3 %AD. Conclusion: This foam model is, therefore, indispensable in selecting a suitable amine for an amine-based CO2 capture plant design and operation.

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Bae, Sa-Rang, Tae Won Lee, Kwangyong Park, and Soo Young Kim. "Tuning of Graphene Work Function by Alkyl Chain Length in Amine-Based Compounds." Electronic Materials Letters 15, no. 2 (December 12, 2018): 141–48. http://dx.doi.org/10.1007/s13391-018-00109-4.

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Ishida, H., and D. P. Sanders. "Regioselectivity of the ring-opening polymerization of monofunctional alkyl-substituted aromatic amine-based benzoxazines." Polymer 42, no. 7 (March 2001): 3115–25. http://dx.doi.org/10.1016/s0032-3861(00)00498-5.

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Zeng, Weili, Yujie Song, Jianning Zhang, Hong Chen, Ming Liu, and Wangqiao Chen. "Insights into the Intrinsic Factors Affecting the NIR Reflectance Based on Rylene Diimide Molecules." Materials 14, no. 18 (September 13, 2021): 5269. http://dx.doi.org/10.3390/ma14185269.

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A clear understanding of the relationships between molecular structure and NIR reflectance (700–2500 nm) behavior is important and highly desirable for developing appropriate NIR-reflective materials to combat NIR heat radiation from sunlight. In this research, three groups of imide-based compounds have been adopted to investigate the influence of the intrinsic molecular structures on the NIR-reflective properties. It is found out that for the compounds with alkyl groups, the NIR reflectance will increase as the degree of the conjugated backbone increases, especially for the reflectance from 1750 nm to 2500 nm. In addition, despite that the alkyl or amine groups deteriorate the NIR reflectance, the NIR reflectance varies within a certain interval and the isomers with branched alkyl groups show identical or smaller NIR reflectance than those of isomers with linear alkyl groups. For different compounds, crystallinity seems to almost have no relationship with their NIR reflectance.

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Mora, Tayouo, Boutevin, David, and Caillol. "Synthesis of Pluri-Functional Amine Hardeners from Bio-Based Aromatic Aldehydes for Epoxy Amine Thermosets." Molecules 24, no. 18 (September 9, 2019): 3285. http://dx.doi.org/10.3390/molecules24183285.

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Most of the current amine hardeners are petro-sourced and only a few studies have focused on the research of bio-based substitutes. Hence, in an eco-friendly context, our team proposed the design of bio-based amine monomers with aromatic structures. This work described the use of the reductive amination with imine intermediate in order to obtain bio-based pluri-functional amines exhibiting low viscosity. The effect of the nature of initial aldehyde reactant on the hardener properties was studied, as well as the reaction conditions. Then, these pluri-functional amines were added to petro-sourced (diglycidyl ether of bisphenol A, DGEBA) or bio-based (diglycidyl ether of vanillin alcohol, DGEVA) epoxy monomers to form thermosets by step growth polymerization. Due to their low viscosity, the epoxy-amine mixtures were easily homogenized and cured more rapidly compared to the use of more viscous hardeners (<0.6 Pa s at 22 °C). After curing, the thermo-mechanical properties of the epoxy thermosets were determined and compared. The isophthalatetetramine (IPTA) hardener, with a higher number of amine active H, led to thermosets with higher thermo-mechanical properties (glass transition temperatures (Tg and Tα) were around 95 °C for DGEBA-based thermosets against 60 °C for DGEVA-based thermosets) than materials from benzylamine (BDA) or furfurylamine (FDA) that contained less active hydrogens (Tg and Tα around 77 °C for DGEBA-based thermosets and Tg and Tα around 45 °C for DGEVA-based thermosets). By comparing to industrial hardener references, IPTA possesses six active hydrogens which obtain high cross-linked systems, similar to industrial references, and longer molecular length due to the presence of two alkyl chains, leading respectively to high mechanical strength with lower Tg.

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Jadhav, Manoj, Jayraj V. Vaghasiya, Dinesh Patil, Saurabh S. Soni, and Nagaiyan Sekar. "Effect of donor modification on the photo-physical and photo-voltaic properties of N-alkyl/aryl amine based chromophores." New Journal of Chemistry 43, no. 23 (2019): 8970–81. http://dx.doi.org/10.1039/c8nj06196c.

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Six push–pull sensitizers (MD1 to MD6) having rhodanine-3-acetic acid acting as an electron withdrawing group and N-alkyl/aryl amine as a donor moiety were planned and prepared to rationalize the influence of donor alteration on absorption/emission properties and photon to current conversion efficiency (η).

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Kalendova, A., M. Pospisil, L. Kovarova, D. Merinska, M. Valaskova, H. Vlkova, J. Simonik, and P. Capkova. "Influence of chain length on intercalation process of polyvinylchloride/clay nanocomposites based on alkyl-amine." Plastics, Rubber and Composites 33, no. 7 (September 2004): 279–86. http://dx.doi.org/10.1179/174328904x19967.

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Abu Tahari, Maratun Najiha, Azizul Hakim Lahuri, Zaitun Ghazali, Salma Samidin, Siti Sarahah Sulhadi, Norliza Dzakaria, and Mohd Ambar Yarmo. "Application of Octadecylamine-Based Adsorbent on Carbon Dioxide Capture." Materials Science Forum 1010 (September 2020): 367–72. http://dx.doi.org/10.4028/www.scientific.net/msf.1010.367.

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Porous surface of silica gel (SG) have been modified with alkyl fatty amine compounds (octadecylamine, ODA) via wet impregnation process. The ODA-based adsorbents were physically characterized by XRD. The presence of crystalline peaks on ODA/SG diffractograms were ascertained the well-dispersion of ODA on the SG surface. XRD analysis displayed the increasing intensity of crystalline ODA with higher percent amine loaded and shifting of the several crystalline peaks of ODA verified the interaction of SG600-ODA. Capacity of CO2 capture by prepared solid adsorbents were evaluated using CO2 adsorption-desorption isotherms. This study shows that increasing percentage of ODA were improved the amount of CO2 uptake by following this trend: 35ODA/SG > 25ODA/SG > 15ODA/SG > SG > 5ODA/SG. However, promotion of 5 wt.% ODA unabled to enhance the capacity of CO2 captured due to pore blockage and reduction in SG pore surface, thus hindered the physisorption between CO2 and SG.

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Qian, Yuqing, Xiaowei An, Xiaofei Huang, Xiangqiang Pan, Jian Zhu, and Xiulin Zhu. "Recyclable Self-Healing Polyurethane Cross-Linked by Alkyl Diselenide with Enhanced Mechanical Properties." Polymers 11, no. 5 (May 1, 2019): 773. http://dx.doi.org/10.3390/polym11050773.

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Dynamic structures containing polymers can behave as thermosets at room temperature while maintaining good mechanical properties, showing good reprocessability, repairability, and recyclability. In this work, alkyl diselenide is effectively used as a dynamic cross-linker for the design of self-healing poly(urea–urethane) elastomers, which show quantitative healing efficiency at room temperature, without the need for any catalysts or external interventions. Due to the combined action of the urea bond and amide bond, the material has better mechanical properties. We also compared the self-healing effect of alkyl diselenide-based polyurethanes and alkyl disulfide-based polyurethanes. The alkyl diselenide has been incorporated into polyurethane networks using a para-substituted amine diphenyl alkyl diselenide. The resulting materials not only exhibit faster self-healing properties than the corresponding disulfide-based materials, but also show the ability to be processed at temperatures as low as 60 °C.

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Shawabkeh, Reyad, Rihan Rihan, and Nawaf AL‐Baker. "Effect of an alkyl amine‐based corrosion inhibitor for 1018 carbon steel pipeline in sea water." Anti-Corrosion Methods and Materials 60, no. 5 (September 9, 2013): 259–70. http://dx.doi.org/10.1108/acmm-06-2013-1270.

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Arderne, Charmaine, Kyle Fraser Batchelor, Bhawna Uprety, Rahul Chandran, and Heidi Abrahamse. "Reactivity trends of cobalt(III) complexes towards various amino acids based on the properties of the amino acid alkyl chains." Acta Crystallographica Section C Structural Chemistry 76, no. 7 (June 5, 2020): 663–72. http://dx.doi.org/10.1107/s2053229620007123.

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The reactivity of the cobalt(III) complexes dichlorido[tris(2-aminoethyl)amine]cobalt(III) chloride, [CoCl2(tren)]Cl, and dichlorido(triethylenetetramine)cobalt(III) chloride, [CoCl2(trien)]Cl, towards different amino acids (L-proline, L-asparagine, L-histidine and L-aspartic acid) was explored in detail. This study presents the crystal structures of three amino acidate cobalt(III) complexes, namely, (L-prolinato-κ2 N,O)[tris(2-aminoethyl)amine-κ4 N,N′,N′′,N′′′]cobalt(III) diiodide monohydrate, [Co(C5H8NO2)(C6H18N4)]I2·H2O, I, (L-asparaginato-κ2 N,O)[tris(2-aminoethyl)amine-κ4 N,N′,N′′,N′′′]cobalt(III) chloride perchlorate, [Co(C4H7N2O3)(C6H18N4)](Cl)(ClO4), II, and (L-prolinato-κ2 N,O)(triethylenetetramine-κ4 N,N′,N′′,N′′′)cobalt(III) chloride perchlorate, [Co(C4H7N2O3)(C6H18N4)](Cl)(ClO4), V. The syntheses of the complexes were followed by characterization using UV–Vis spectroscopy of the reaction mixtures and the initial rates of reaction were obtained by calculating the slopes of absorbance versus time plots. The initial rates suggest a stronger reactivity and hence greater affinity of the cobalt(III) complexes towards basic amino acids. The biocompatibility of the complexes was also assessed by evaluating the cytotoxicity of the complexes on cultured normal human fibroblast cells (WS1) in vitro. The compounds were found to be nontoxic after 24 h of incubation at concentrations up to 25 mM.

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Zhong, Di-Chang, Lie-Qiang Liao, Ke-Jun Wang, Hui-Jin Liu, and Xu-Zhong Luo. "Heat-set gels formed from easily accessible gelators of a succinamic acid derivative (SAD) and a primary alkyl amine (R-NH2)." Soft Matter 11, no. 32 (2015): 6386–92. http://dx.doi.org/10.1039/c5sm01305d.

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We report here a gel system based on two-component gelators containing a succinamic acid derivative (SAD) and a primary alkyl amine (R-NH₂), from which the formation of heat-set gels, conventional gels and irreversible heat-set gels can be achieved in aromatic solvents.

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Wang, Maohuai, Shuxian Wei, Zhonghua Wu, Sainan Zhou, Zhaojie Wang, Jiahui Wang, and Xiaoqing Lu. "Alkyl amine functionalized triphenylamine-based covalent organic frameworks for high-efficiency CO2 capture and separation over N2." Materials Letters 230 (November 2018): 28–31. http://dx.doi.org/10.1016/j.matlet.2018.07.071.

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Pineschi, Mauro, Federica Del Moro, Paolo Crotti, and Franco Macchia. "Catalytic asymmetric ring-opening of cyclopentadiene - heterodienophile cycloadducts with organometallic reagents." Pure and Applied Chemistry 78, no. 2 (January 1, 2006): 463–67. http://dx.doi.org/10.1351/pac200678020463.

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An unprecedented catalytic asymmetric ring-opening of easily accessible 2,3-heterosubstituted norbornenes with hard alkyl metals (R-M), is able to give a practical regio- and stereoselective access to hetero-functionalized alkyl cyclopentenes in an enantioenriched form. The copper-catalyzed desymmetrization reaction with trialkylaluminums of sterically hindered and rigid, tri- or tetracyclic Diels-Alder adducts, easily available by cycloaddition reaction of cyclopentadiene with 4-phenyl-urazole and 2,3-phthalazine-1,4-dione, proved to be particularly efficient. Interestingly, the chirality of the amine part of the BINOL-based phosphoramidite is able to impose the absolute stereochemistry of the corresponding adducts.

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Trivedi, Jaladhi S., Anupam Bera, and Suresh K. Jewrajka. "Alkyl amine functional dextran macromonomer-based thin film composite loose nanofiltration membranes for separation of charged and neutral solutes." Journal of Applied Polymer Science 134, no. 37 (May 28, 2017): 45301. http://dx.doi.org/10.1002/app.45301.

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Cheng, Hong-Jian, Ya-Li Shen, Yi-Feng Lu, Ji Ma, Hong-Wei Ji, Wen-Yu Yin, Xiao-Yan Tang, Yun-Sheng Ma, and Rong-Xin Yuan. "Alkyl group-directed assembly of coordination polymers based on bis-(4-imidazol-1-yl-phenyl)-amine and their photocatalytic properties." New Journal of Chemistry 40, no. 3 (2016): 2479–88. http://dx.doi.org/10.1039/c5nj02760h.

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Kumari, Kavitha, and Sanjeev Maken. "Optical Properties, Excess Volume Prediction from Refractive Index and Intermolecular Interactions in Dibutylamine + Isomeric Butanol." Asian Journal of Chemistry 33, no. 6 (2021): 1287–93. http://dx.doi.org/10.14233/ajchem.2021.23000.

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The alkyl or alkanol amines are widely used as absorbent for CO2 capture owing to interaction between amines and CO2. In order to increase the CO2 loading in amine based absorbents, blending of amine with alkanol may be one option. As thermophysical properties of of utmost importance in designing, in present work, the refractive index of dibutylamine (DBA) and isomeric butanol as well as their binary mixtures at 298.15 K to 308.15 K were measured. The Δn are found positive for DBA + isomeric butanol mixtures. The Δn values were correlated with Redlich-Kister polynomial. The refractive index data were also predicted by various correlations and results were expressed in terms of standard deviation. The Δn values were also employed to calculate the excess molar volume of the present binary mixtures. Further Δn data analysed in terms of intermolecular interaction among DBA (1) + isomeric butanol (2) mixtures.

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Pankow, J. F., and W. E. Asher. "SIMPOL.1: a simple group contribution method for predicting vapor pressures and enthalpies of vaporization of multifunctional organic compounds." Atmospheric Chemistry and Physics 8, no. 10 (May 29, 2008): 2773–96. http://dx.doi.org/10.5194/acp-8-2773-2008.

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Abstract. The SIMPOL.1 group contribution method is developed for predicting the liquid vapor pressure poL (atm) and enthalpy of vaporization Δ Hvap (kJ mol-1) of organic compounds as functions of temperature (T). For each compound i, the method assumes log10poL,i (T)=∑kνk,ibk(T) where νk,i is the number of groups of type k, and bk (T) is the contribution to log10poL,i (T) by each group of type k. A zeroeth group is included that uses b0 (T) with ν0,i=1 for all i. A total of 30 structural groups are considered: molecular carbon, alkyl hydroxyl, aromatic hydroxyl, alkyl ether, alkyl ring ether, aromatic ether, aldehyde, ketone, carboxylic acid, ester, nitrate, nitro, alkyl amine (primary, secondary, and tertiary), aromatic amine, amide (primary, secondary, and tertiary), peroxide, hydroperoxide, peroxy acid, C=C, carbonylperoxynitrate, nitro-phenol, nitro-ester, aromatic rings, non-aromatic rings, C=C–C=O in a non-aromatic ring, and carbon on the acid-side of an amide. The T dependence in each of the bk (T) is assumed to follow b(T)=B1/T+B2+B3T+B4ln T. Values of the B coefficients are fit using an initial basis set of 272 compounds for which experimentally based functions po L,i=fi (T) are available. The range of vapor pressure considered spans fourteen orders of magnitude. The ability of the initially fitted B coefficients to predict poL values is examined using a test set of 184 compounds and a T range that is as wide as 273.15 to 393.15 K for some compounds. σFIT is defined as the average over all points of the absolute value of the difference between experimental and predicted values of log10poL,i (T). After consideration of σFIT for the test set, the initial basis set and test set compounds are combined, and the B coefficients re-optimized. For all compounds and temperatures, σFIT=0.34: on average, poL,i (T) values are predicted to within a factor of 2. Because d(log10 poL,i (T))d(1/T) is related to the enthalpy of vaporization ΔHvap,i, the fitted B provide predictions of ΔHvap,i based on structure.

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Pankow, J. F., and W. E. Asher. "SIMPOL.1: A simple group contribution method for predicting vapor pressures and enthalpies of vaporization of multifunctional organic compounds." Atmospheric Chemistry and Physics Discussions 7, no. 4 (August 13, 2007): 11839–94. http://dx.doi.org/10.5194/acpd-7-11839-2007.

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Abstract. The SIMPOL.1 group contribution method is developed for predicting the liquid vapor pressure pLo (atm) and enthalpy of vaporization ΔHvap (kJ mol-1) of organic compounds as functions of temperature (T). For each compound i, the method assumes log10pL,io(T)=Σkνk,ibk(T) where νk,i is the number of groups of type k, and bk(T) is the contribution to log10 pL,io(T) by each group of type k. A zeroeth group is included that uses b0(T) with ν0,i=1 for all i. A total of 30 structural groups are considered: molecular carbon, alkyl hydroxyl, aromatic hydroxyl, alkyl ether, alkyl ring ether, aromatic ether, aldehyde, ketone, carboxylic acid, ester, nitrate, nitro, alkyl amine (primary, secondary, and tertiary), aromatic amine, amide (primary, secondary, and tertiary), peroxide, hydroperoxide, peroxy acid, C=C, carbonylperoxynitrate, nitro-phenol, nitro-ester, aromatic rings, non-aromatic rings, C=C–C=O in a non-aromatic ring, and carbon on the acid-side of an amide. The T dependence in each of the bk(T) is assumed to follow b(T)=B1/T+B2+B3T+B4lnT. Values of the B coefficients are fit using an initial basis set of 272 compounds for which experimentally based functions pL,io=fi(T) are available. The range of vapor pressure considered spans fourteen orders of magnitude. The ability of the initially fitted B coefficients to predict pLo values is examined using a test set of 161 compounds and a T range that is as wide as 273.15 to 393.15 K for some compounds. σFIT is defined as the average over all points of the absolute value of the difference between experimental and predicted values of log10pL,io(T). After consideration of σFIT for the test set, the initial basis set and test set compounds are combined, and the B coefficients re-optimized. For all compounds and temperatures, σFIT=0.34: on average, pL,io(T) values are predicted to within a factor of 2. Because d(log10pL,io(T))/d(1/T) is related to the enthalpy of vaporization ΔHvap,i, the fitted B provide predictions of ΔHvap,i based on structure.

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Macuvele, Domingos Lusitâneo Pier, Janaína Nones, Jonas V. Matsinhe, A. T. Bezerra, M. M. Lima, E. S. W. Santos, Márcio Antônio Fiori, and Humberto Gracher Riella. "Simultaneous Effect of Reaction Temperature and Concentration of Surfactant in Organo-Bentonite Synthesis." Materials Science Forum 899 (July 2017): 42–47. http://dx.doi.org/10.4028/www.scientific.net/msf.899.42.

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Transmission infrared spectroscopy (FTIR) was used to study the effect of the temperature and concentration of octadecylamine (surfactant) in the conformation state of amine chains incorporated in a bentonite matrix by organophilization process. The temperature is the most important factor in conformational changes-gauche/trans. Whereas the simultaneous increase of the temperature and concentration of surfactant favors the disordered conformation-gauche. This result is very important in the development of organo-bentonite based polymeric nanocomposites because the intercalation of the polymer in the galleries of the organo-bentonite is dependent on the conformation of the alkyl chains.

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Jabbour, Adel, Reem Smoum, Khuloud Takrouri, Eli Shalom, Batia Zaks, Doron Steinberg, Abraham Rubinstein, Israel Goldberg, Jehoshua Katzhendler, and Morris Srebnik. "Pharmacologically active boranes." Pure and Applied Chemistry 78, no. 7 (January 1, 2006): 1425–53. http://dx.doi.org/10.1351/pac200678071425.

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Novel methods are described for the preparation of alkyldimethylamine cyanoboranes and β-hydroxylalkyldimethylamine cyanoboranes by C-lithiation of trimethylamine cyanoboranes followed by reaction with alkyl halides, aldehydes, and ketones. Lithiation of the monobromo derivatives of amine cyanoboranes led to the synthesis of the first examples of diborane derivatives of amine cyanoboranes. Bromo derivatives of amine cyanoboranes and amine carboxyboranes have been synthesized by new simple and efficient methods. Amine fluorocyanoboranes and amine fluorocarboxyboranes, new classes of compounds, have been prepared from the bromo precursors by fluorine/bromine exchange using fluorinating reagents such as AgF and Et3N.3HF. Eight different derivatives of oxazaborolidines were synthesized and evaluated for their affect on Streptococcus mutans viability, adhesion, and biofilm formation using 3[H]-thymidine labeled bacteria, and fluorescent stained bacteria. This is the first reported antibacterial activity of this class of compounds. The minimal inhibitory concentration (MIC) values ranged from 0.26 to 10 mM. Structure-activity relationship was observed. The B-butyl moiety of the oxazaborolidines contributed an anti-adhesion effect for all derivatives, while its effect diminished when the boron atom was incorporated in a fused heterocyclic ring. The B-phenyl group induced bacterial adhesion in all tested compounds. In a separate study for boronated saccahrides and enzymatic inhibition, the complex formation between N-butylboronic acid and a series of monosaccharides was investigated by 1H, 13C, and 11B NMR spectroscopy and gas chromatography-mass spectrometry (GC-MS). Then, a series of boronic acid compounds with protease inhibition properties were prepared. The effect of added mono-, di-, and polysaccharides on the inhibitory activity of these compounds was studied. Potassium organotrifluoroborates were found to be reversible competitive inhibitors of α-chymotrypsin and trypsin. Based on 19F NMR, it was speculated that they inactivate the enzymes as a result of the formation of hydrogen bonds between fluorine atoms of the inhibitors and the serine protease.

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Schmidt and Eschig. "Hydrophobilization of Furan-Containing Polyurethanes via Diels–Alder Reaction with Fatty Maleimides." Polymers 11, no. 8 (July 31, 2019): 1274. http://dx.doi.org/10.3390/polym11081274.

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We describe new hydrophobic functionalized linear polyurethane resins by combining N-alkyl maleimides via the Diels–Alder reaction with linear furan-modified polyurethanes. This procedure provides the opportunity for the post-polymerization-functionalizing of polyurethanes. Access to furan-bearing polyurethanes is achieved via the reaction of a furan-containing diol, polyethylenglycol (PEG), and different diisocyanates. The furan-containing diol is obtained from the reaction of furfurylamine and two equivalents of hydroxyalkyl acrylate. The resulting furan-bearing polyurethanes are reacted with fatty amine-based N-alkyl maleimides. The maleimide and furan functionalities undergo a Diels–Alder reaction, which allows for the covalent bonding of the hydrophobic side chains to the polyurethane backbone. The covalent bonding of the hydrophobic maleimides to the polyurethane backbone is proven by means of NMR. The influence of the functionalization on the surface properties of the resulting polyurethane films is analyzed via the determination of surface energy via the sessile drop method.

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Tamura, Kenji, Hikaru Uno, and Hirohisa Yamada. "Synthesis and Characterization of Exfoliated Natural Mica/Polymer Nanocomposites." Materials Science Forum 539-543 (March 2007): 948–55. http://dx.doi.org/10.4028/www.scientific.net/msf.539-543.948.

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The effect of natural mica on the morphology and properties of polyamide 6 (PA-6) nanocomposites was examined. Natural mica (sericite) acquired from a well-known mine in Shimane, Japan was ion-exchanged with an alkyl amine hydrochloride compound. The resulting organomica was extruded with PA-6 using a twin-screw extruder. Quantitative analysis of TEM photomicrographs of the nanocomposite reveal a fairly large average particle length and a higher degree of platelet exfoliation for the natural mica-based nanocomposite compared to the clay version, thus translating into a higher particle aspect ratio. The resulting nanomica/PA-6 composite exhibits a high degree of mica exfoliation and improved thermal mechanical properties.

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Pacia, Rose Mardie, Clinton Manianglung, and Young Soo Ko. "In Situ IR Study on Effect of Alkyl Chain Length between Amines on Its Stability against Acidic Gases." Catalysts 9, no. 11 (October 30, 2019): 910. http://dx.doi.org/10.3390/catal9110910.

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For the CO2 capture process via the cyclic adsorption/desorption method, one emerging catalyst is the use of amine-functionalized silica. This study focused on comparing the CO2 capture performance of diamines with ethyl and propyl spacers and the degradation species formed after long-term exposure to various acidic gases such as SO2 and NO2 at elevated temperatures. Adsorbents were prepared via the incipient wetness technique and then subjected to thermogravimetric measurements and in situ FT-IR analyses. 2NS-P/Kona95, which contains a propyl spacer, showed fewer degradation species formed based on its IR spectra and better stability with its long-term exposure to various acidic gases. Thus, the incorporation of amines with a large number of nitrogen groups of propyl or longer spacer length could be a promising CO2 capture material.

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Ma, Shuchao, Ben Ouyang, Linan Wang, and Lei Yao. "Design and Biological Evaluation of 3-Aryl-4-alkylpyrazol-5-amines Based on the Target Fishing." Current Computer-Aided Drug Design 16, no. 5 (November 9, 2020): 564–70. http://dx.doi.org/10.2174/1573409915666191003123900.

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Background: Pyrazol-5-amine derivatives are an important class of heterocyclic compounds. However, there are less 4-alkyl substituted pyrazoles reported. Objective: Here reported are the design, synthesis and biological evaluation of 3-aryl-4- alkylpyrazol-5-amines derivatives. Methods: A serials of 3-aryl-4-alkylpyrazol-5-amines were designed and the biological action targets were screened by target fishing function of Discovery Studio software. The synthesis route involved 3-oxo-3-arylpropanenitrile formation, alkylation, pyrazole formation, and amides formation. The antitumor activities of these compounds were carried out by thiazolyl blue tetrazolium bromide (MTT) method using U-2 OS (osteosarcoma) and A549 (lung cancer) tumor cells. Results: Eight 3-aryl-4-alkylpyrazol-5-amines were synthesized, and their structures were verified by 1H NMR, 13C NMR, and HRMS. Thirteen pharmacophores were mapped out by target fishing. Compound 5h showed anti-proliferation activities against U-2 OS and A549 tumor cell with IC50 value of 0.9 μM and 1.2 μM, respectively. Conclusion: Compound 5h might represent a promising scaffold for the further development of novel antitumor drugs.

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Ran, De Long, Jian Jun Xie, Kai Huang, Shui Ping Yin, Sheng Ming Chen, and Ying She Luo. "High Temperature Resistance of Epoxy Adhesives under the Room-Temperature Curing." Advanced Materials Research 284-286 (July 2011): 1804–7. http://dx.doi.org/10.4028/www.scientific.net/amr.284-286.1804.

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High-temperature resistant epoxy adhesives cured under room-temperature becomes more and more important in many industries such as aerospace and aviation, the locomotive and diesel, etc. In this paper three self-made amine-based mannich-amide was mixed with E-44 epoxy resin under the same technological parameters, and the epoxy adhesives cured by the three amine-based mannich-amides under room-temperature are tested by FTIR, TGA and DMA. Results of TGA show a quicker drop in weight occurrence within 150-250°C for epoxy networks cured by multiamine-based mannich amides than the long-chain alkyl one. Results of FTIR show completely curing of epoxy adhesives cured by mannich amides under room temperature and the height of absorption band 1502cm-1(C-N) is much lower after 12h under 150°C,200°C atmosphere than 25°C. Results of DMA show that the Tg determined by DMA has an order EP AN2(89.9°C) >EP AN1(89.7°C)>EP AN3(80.8°C). In the rest results of DMA, the EP-AN3 system has the biggest storage modulus (E’) within 100-150°C while the EP-AN3 system has the smallest loss modulus(E”) within 100-150°C. As a whole, the epoxy adhesives cured by AN3 under room-temperature have the best high temperature resistance.

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Hou, Mingyue, Zhaohua Zhou, Ao Xu, Kening Xiao, Jiakun Li, Donghuan Qin, Wei Xu, and Lintao Hou. "Synthesis of Group II-VI Semiconductor Nanocrystals via Phosphine Free Method and Their Application in Solution Processed Photovoltaic Devices." Nanomaterials 11, no. 8 (August 15, 2021): 2071. http://dx.doi.org/10.3390/nano11082071.

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Solution-processed CdTe semiconductor nanocrystals (NCs) have exhibited astonishing potential in fabricating low-cost, low materials consumption and highly efficient photovoltaic devices. However, most of the conventional CdTe NCs reported are synthesized through high temperature microemulsion method with high toxic trioctylphosphine tellurite (TOP-Te) or tributylphosphine tellurite (TBP-Te) as tellurium precursor. These hazardous substances used in the fabrication process of CdTe NCs are drawing them back from further application. Herein, we report a phosphine-free method for synthesizing group II-VI semiconductor NCs with alkyl amine and alkyl acid as ligands. Based on various characterizations like UV-vis absorption (UV), transmission electron microscope (TEM), and X-ray diffraction (XRD), among others, the properties of the as-synthesized CdS, CdSe, and CdTe NCs are determined. High-quality semiconductor NCs with easily controlled size and morphology could be fabricated through this phosphine-free method. To further investigate its potential to industrial application, NCs solar cells with device configuration of ITO/ZnO/CdSe/CdTe/Au and ITO/ZnO/CdS/CdTe/Au are fabricated based on NCs synthesized by this method. By optimizing the device fabrication conditions, the champion device exhibited power conversion efficiency (PCE) of 2.28%. This research paves the way for industrial production of low-cost and environmentally friendly NCs photovoltaic devices.

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HAN, Won-Sik, Su-Jung YOO, Sung-Hoon KIM, Tae-Kee HONG, and Koo-Chun CHUNG. "Behavior of a Polypyrrole Solid Contact pH-Selective Electrode Based on Tertiary Amine Ionophores Containing Different Alkyl Chain Lengths between Nitrogen and a Phenyl Group." Analytical Sciences 19, no. 3 (2003): 357–60. http://dx.doi.org/10.2116/analsci.19.357.

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Das, Pranab J., and Jupitara Das. "Synthesis of aryl/alkyl(2,2′-bis-3-methylindolyl)methanes and aryl(3,3′-bis indolyl)methanes promoted by secondary amine based ionic liquids and microwave irradiation." Tetrahedron Letters 53, no. 35 (August 2012): 4718–20. http://dx.doi.org/10.1016/j.tetlet.2012.06.106.

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Al-Resayes, Saud I., Mohammad Azam, Mahboob Alam, Raju Suresh Kumar, and S. F. Adil. "Synthesis, crystal structure and Hirschfeld surface analyses of an alkyl amine based salt, [C 5 H 16 N 2 ][ZnCl 4 ] and its enzyme inhibition activity." Journal of Saudi Chemical Society 21, no. 4 (May 2017): 481–86. http://dx.doi.org/10.1016/j.jscs.2016.12.002.

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36

Krátký, Martin, Zsuzsa Baranyai, Šárka Štěpánková, Katarína Svrčková, Markéta Švarcová, Jiřina Stolaříková, Lilla Horváth, Szilvia Bősze, and Jarmila Vinšová. "N-Alkyl-2-[4-(trifluoromethyl)benzoyl]hydrazine-1-carboxamides and Their Analogues: Synthesis and Multitarget Biological Activity." Molecules 25, no. 10 (May 12, 2020): 2268. http://dx.doi.org/10.3390/molecules25102268.

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Based on the isosterism concept, we have designed and synthesized homologous N-alkyl-2-[4-(trifluoromethyl)benzoyl]hydrazine-1-carboxamides (from C1 to C18) as potential antimicrobial agents and enzyme inhibitors. They were obtained from 4-(trifluoromethyl)benzohydrazide by three synthetic approaches and characterized by spectral methods. The derivatives were screened for their inhibition of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) via Ellman’s method. All the hydrazinecarboxamides revealed a moderate inhibition of both AChE and BuChE, with IC50 values of 27.04–106.75 µM and 58.01–277.48 µM, respectively. Some compounds exhibited lower IC50 for AChE than the clinically used drug rivastigmine. N-Tridecyl/pentadecyl-2-[4-(trifluoromethyl)benzoyl]hydrazine-1-carboxamides were identified as the most potent and selective inhibitors of AChE. For inhibition of BuChE, alkyl chain lengths from C5 to C7 are optimal substituents. Based on molecular docking study, the compounds may work as non-covalent inhibitors that are placed in a close proximity to the active site triad. The compounds were evaluated against Mycobacterium tuberculosis H37Rv and nontuberculous mycobacteria (M. avium, M. kansasii). Reflecting these results, we prepared additional analogues of the most active carboxamide (n-hexyl derivative 2f). N-Hexyl-5-[4-(trifluoromethyl)phenyl]-1,3,4-oxadiazol-2-amine (4) exhibited the lowest minimum inhibitory concentrations within this study (MIC ≥ 62.5 µM), however, this activity is mild. All the compounds avoided cytostatic properties on two eukaryotic cell lines (HepG2, MonoMac6).

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Telitel, Sofia, Frédéric Dumur, Thomas Faury, Bernadette Graff, Mohamad-Ali Tehfe, Didier Gigmes, Jean-Pierre Fouassier, and Jacques Lalevée. "New core-pyrene π structure organophotocatalysts usable as highly efficient photoinitiators." Beilstein Journal of Organic Chemistry 9 (May 7, 2013): 877–90. http://dx.doi.org/10.3762/bjoc.9.101.

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Eleven di- and trifunctional compounds based on a core-pyrene π structure (Co_Py) were synthesized and investigated for the formation of free radicals. The application of two- and three-component photoinitiating systems (different Co_Pys with the addition of iodonium or sulfonium salts, alkyl halide or amine) was investigated in detail for cationic and radical photopolymerization reactions under near-UV–vis light. The proposed compounds can behave as new photocatalysts. Successful results in terms of rates of polymerization and final conversions were obtained. The strong MO coupling between the six different cores and the pyrene moiety was studied by DFT calculations. The different chemical intermediates are characterized by ESR and laser flash photolysis experiments. The mechanisms involved in the initiation step are discussed, and relationships between the core structure, the Co_Py absorption property, and the polymerization ability are tentatively proposed.

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Palange, Caterina, Marcus A. Johns, David J. Scurr, Jonathan S. Phipps, and Stephen J. Eichhorn. "The effect of the dispersion of microfibrillated cellulose on the mechanical properties of melt-compounded polypropylene–polyethylene copolymer." Cellulose 26, no. 18 (September 27, 2019): 9645–59. http://dx.doi.org/10.1007/s10570-019-02756-8.

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Abstract Microfibrillated cellulose (MFC) is a highly expanded, high surface area networked form of cellulose-based reinforcement. Due to the poor compatibility of cellulose with most common apolar thermoplastic matrices, the production of cellulose-reinforced composites in industry is currently limited to polar materials. In this study, a facile water-based chemistry, based on the reaction of MFC with tannic acid and subsequent functionalisation with an alkyl amine, is used to render the surface of the MFC fibrils hydrophobic and enhance the dispersion of the cellulose-based filler into an apolar thermoplastic matrix. The level of dispersion of the compatibilized MFC reinforced composites was evaluated using Time of Flight Secondary Ion Mass Spectrometry and multi-channel Spectral Confocal Laser Scanning Microscopy. The agglomeration of cellulosic filler within the composites was reduced by functionalising the surface of the MFC fibrils with tannic acid and octadecylamine. The resulting composites exhibited an increase in modulus at a high cellulose content. Despite the dispersion of a large portion of the functionalised filler, the presence of some remaining aggregates affected the impact properties of the composites produced.

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Roy Chowdhury, Srayoshi, Sujay Kumar Nandi, Sahabaj Mondal, Santosh Kumar, and Debasish Haldar. "White-Light-Emitting Supramolecular Polymer Gel Based on β-CD and NDI Host-Guest Inclusion Complex." Polymers 13, no. 16 (August 17, 2021): 2762. http://dx.doi.org/10.3390/polym13162762.

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Supramolecular polymer formed by non-covalent interactions between complementary building blocks entraps solvents and develops supramolecular polymer gel. A supramolecular polymer gel was prepared by the heating-cooling cycle of β-cyclodextrin (β-CD) and naphthalenedimide (NDI) solution in N,N-dimethylformamide (DMF). The host-guest inclusion complex of β-CD and NDI 1 containing dodecyl amine forms the supramolecular polymer and gel in DMF. However, β-CD and NDI 2, having glutamic acid, fail to form the supramolecular polymer and gel under the same condition. X-ray crystallography shows that the alkyl chains of NDI 1 are complementary to the hydrophobic cavity of the two β-CD units. From rheology, the storage modulus was approximately 1.5 orders of magnitude larger than the loss modulus, which indicates the physical crosslink and elastic nature of the thermo-responsive gel. FE-SEM images of the supramolecular polymer gel exhibit flake-like morphology and a dense flake network. The flakes developed from the assembly of smaller rods. Photophysical studies show that the host-guest complex formation and gelation have significantly enhanced emission intensity with a new hump at 550 nm. Upon excitation by a 366 nm UV-light, NDI 1 and β-CD gel in DMF shows white light emission. The gel has the potential for the fabrication of organic electronic devices.

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Das, Pranab J., and Jupitara Das. "ChemInform Abstract: Synthesis of Aryl/Alkyl(2,2′-bis-3-methylindolyl)methanes and Aryl(3,3′-bis-indolyl)methanes Promoted by Secondary Amine Based Ionic Liquids and Microwave Irradiation." ChemInform 43, no. 48 (November 8, 2012): no. http://dx.doi.org/10.1002/chin.201248108.

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41

Wang, Ruijuan, Yu Lei, Zikun Mei, Dong Wang, and Zhigang Yin. "Synthesis and Aggregation of Novel Sugar-based Gemini Surfactants in Aqueous Solution." Tenside Surfactants Detergents 58, no. 5 (September 1, 2021): 401–6. http://dx.doi.org/10.1515/tsd-2020-2292.

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Abstract Novel sugar-based gemini surfactants with a 1,3-propan-2-ol spacer (1, 3-(N- alkyl-2-D-glucosaminyl acetyl) propan-2-ol, Glu(n)-3(OH)-Glu(n), n = 12, 14) were synthesized with D-(+)-glucono-1,5-lactone as starting material in two steps, whose structures were confirmed using proton nuclear magnetic resonance spectroscopy (1H NMR) and carbon nuclear magnetic resonance carbon spectroscopy (13C NMR). The micellization of Glu(n)-3(OH)-Glu(n) (n = 12, 14) in aqueous solution at 25.0°C was investigated by using surface tension measurement. The results show that the critical micelle concentration (CMC) of Glu(12)-3(OH)-Glu(12) is around 10–5 mol × L–1, and is one order of magnitude smaller than that of Glu(14)-3(OH)-Glu(14), indicating that the surface activity of Glu(12)-3(OH)-Glu(12) is superior to that of Glu(14)-3(OH)-Glu(14). Moreover, the aggregation behavior of Glu(12)-3(OH)-Glu(12) in aqueous solution at different pH values was investigated by surface tension, dynamic light scattering (DLS), and cryogenic transmission electron microscopic (Cryo-TEM) measurements. The results indicate that the CMC slightly increases with the decrease of the solution pH. The microstructure of Glu(12)-3(OH)-Glu(12) aggregates transitions from micelle to vesicle with the solution pH from acidic to neutral and alkaline. The microstructural transformation of Glu(12)-3(OH)-Glu(12) with the solution pH is mainly determined by the protonation of the two tertiary amine nitrogen atoms in its hydrophilic headgroups.

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42

Tee, Oswald S., Timothy A. Gadosy, and Javier B. Giorgi. "Dissociation constants of host–guest complexes of alkyl-bearing compounds with β-cyclodextrin and "hydroxypropyl-β-cyclodextrin"." Canadian Journal of Chemistry 74, no. 5 (May 1, 1996): 736–44. http://dx.doi.org/10.1139/v96-080.

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Dissociation constants (Kd) of host–guest complexes formed from β-cyclodextrin or "hydroxypropyl-β-cyclodextrin" (β-CD and Hp-β-CD) and several types of aliphatic guests (alcohols, alkanesulfonate ions, alkylamines, and α-amino acids), with up to eight carbons in a chain, are reported. These constants were determined by inhibition kinetics and by a spectrofluorometric displacement method based on competition with 1-anilino-8-naphthalenesulfonate ion as a fluorescent probe. The value of Kd for a particular amine is close to that for the corresponding alcohol. For linear alkyl derivatives, there are strong correlations between pKd (= −log Kd) and the chain length of the guest, with slopes around 0.5, complementing trends that were noted earlier. Furthermore, the strengths of binding of various aliphatic derivatives to β-CD and to Hp-β-CD are close, with Kd values for the two CDs usually being within a factor of 2 of each other. Overall, for the binding of over 50 alkyl-bearing derivatives, there is a good correlation of pKd for Hp-β-CD with that for β-CD, with unit slope. These observations imply that the binding of simple aliphatic guests to Hp-β-CD is not greatly influenced by the modification of the hydroxyl groups on the primary side of the β-CD cavity but this may not be true for longer aliphatic derivatives (>C8) or for aromatics that penetrate farther into the CD cavity. Key words: cyclodextrins, host–guest complexes, dissociation constants.

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Bagdasarov, A. S., A. I. Nesterenko, and A. Yu Pupkova. "FOAM GYPSUM PRODUCTS BASED ON LOCAL BINDERS." Herald of Dagestan State Technical University. Technical Sciences 45, no. 4 (June 27, 2019): 153–61. http://dx.doi.org/10.21822/2073-6185-2018-45-4-153-161.

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Objectives. The problems of production of porous gypsum products on a local gypsum binder in the Karachay-Cherkess Republic are considered. Method. The study is based on the method of "dry" mineralization of foams, developed at the Moscow State University of Civil Engineering. As the source materials used plaster binder brand G-6 Ust-Dzhegutinsky plaster plant. An alkyl dimethylamine oxide (amine oxide) foaming agent was chosen as a foaming agent (PO). The choice of software is made taking into account its compatibility with the gypsum binder. At the same time, software of various classes was studied. Studies were performed to obtain foamed gypsum with an average density of 900 kg / m3. Result. A technology for the production of foam gypsum is proposed, based on the technology for the production of foam concrete by the method of “dry” mineralization of foams. The choice of foaming agent was made by comparative evaluation of the studied parameters of foaming agents of various classes. A technique has been developed for designing foamed gypsum formulations to produce products of a given average density. The technique includes the determination of the flow rate of HS, water flow and foaming agent, the determination of the B / T ratio. It was proposed to design the GHG compositions based on a given design average material density (), which in this case is equal to the consumption of dihydrate gypsum (CaSO42H2O). In the proposed method of obtaining foam – gypsum masses, the distinctive feature is the use of the technological properties of dense foams with low multiplicity. The boundary conditions for obtaining wall foam-gypsum products from a local gypsum binder that meet the requirements of GOST have been determined. Conclusion. Using modern research methods, it has been established that foam-hypo products from Ust-Dzhegutinsky gypsum of grade G-6 meet the requirements of standards for building heat-insulating and construction-heatinsulating products with a density of 400-1000 kg / m 3.

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Anbarasu, A., P. Karnan, N. Deepa, and R. Usha. "CARICA PAPAYA MEDIATED GREEN SYNTHESIZED SILVER NANOPARTICLES." International Journal of Current Pharmaceutical Research 10, no. 3 (May 17, 2018): 15. http://dx.doi.org/10.22159/ijcpr.2018v10i3.27221.

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Objective: The present study was designed to biosynthesize NPs from leaves to study the reducing Ag+ions and stabilizing the particles and confirm AgNP synthesis by using various spectroscopy and microscopic methods.Methods: Bio-inspired AgNPs were rapidly synthesized at room temperature using fresh aqueous leaf extract of Carica papaya. A green and low-cost synthesis was effective in the formation of stable crystalline NPs in the solution. Amine, alkene and alkyl halides groups present in the Carica papaya leaf extract functioned as reducing as well as a stabilizing agent to produce shape controlled AgNPs.Results: SPR confirmed the formation of AgNPs in UV-Visible spectra at 445.7 nm. The XRD result also showed the presence of elemental Ag+as a crystalline nature. Study the functional groups responsible for the bio reduction of Ag+. HE-TEM and FE-SEM with EDX image showed spherical crystalline AgNPs.Conclusion: Hence, the plant-based bio AgNPs could be used in biomedical applications.

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Liu, Junzhi, and Xinliang Feng. "Bottom-Up Synthesis of Nitrogen-Doped Polycyclic Aromatic Hydrocarbons." Synlett 31, no. 03 (December 10, 2019): 211–22. http://dx.doi.org/10.1055/s-0039-1690767.

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Bottom-up organic synthesis serves as an efficient method to provide atomically precise heteroatom-doped polycyclic aromatic hydrocarbons (PAHs) with not only well-defined size and edge structures but also specific concentrations and positions of the heteroatoms. We provide a plenary account of the preparation of nitrogen-doped PAHs (N-PAHs) through 1,3-dipolar cycloaddition between different dipolarophiles, as well as pyrazine-type N-doped diaza-hexa-peri-hexabenzocoronene (diaza-HBC). Additionally, we present the synthesis of a class of helical N-charged PAHs, including one charged aza[5]helicene and two charged aza[4]helicenes. Moreover, the bottom-up organic synthesis strategy is further extended to the construction of novel nitrogen-boron-nitrogen (NBN)-containing PAHs. Finally, we discuss the synthesis of four-coordinate boron chromophores containing 6,12,18-tris(alkyl amine)-5,11,17-triazatrinaphthylene derivative ligands.1 Introduction2 Nitrogen-Doped PAHs Based on Dibenzo-9a-azaphenalene (DBAP)3 Cationic Nitrogen-Doped Helical PAHs4 Nitrogen–Boron–Nitrogen-Doped PAHs5 Conclusion and Outlook

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K. Madhup, Mukesh, Nisha K. Shah, and Neha R. Parekh. "An Investigation of Abrasion Resistance Property of Clay- Epoxy Nanocomposite Coating." Material Science Research India 15, no. 2 (July 7, 2018): 165–78. http://dx.doi.org/10.13005/msri/150209.

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Diglycidyl ether of bisphenol A based epoxy resin was loaded with alkyl quaternary ammonium modified bentonite clay nanoparticles (b-CNPs) in various concentrations. The abrasion resistance (Taber) property of the composite coatings cured with amine were investigated after 7 days and with 60 days curing at two different cycle viz. 500 and 1000. The mass losses of the materials revealed the fact that abrasion resistance increases with increase in CNPs concentration inside epoxy matrix with ageing. Thermal (DSC), spectroscopic (FTIR) and morphological (SEM) studies were performed to characterize the developed epoxy nanocomposite (ENC) coating. A gradual decrease in glass transition temperature (Tg) was observed with increase in the b-CNPs concentration. The modified b-CNPs found interacting with epoxy matrix and the intensity found increasing with increase in b-CNPs concentration during spectroscopic study. Smooth film morphology was revealed by scanning electron microscopic analysis confirming the uniform dispersion of b-CNPs inside polymer nanocomposite matrix.

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47

Cichowska-Kopczyńska, Iwona, Dorota Warmińska, and Bartosz Nowosielski. "Solubility of Carbon Dioxide in Deep Eutectic Solvents Based on 3-Amino-1-Propanol and Tetraalkylammonium Salts at Low Pressure." Materials 14, no. 3 (January 27, 2021): 594. http://dx.doi.org/10.3390/ma14030594.

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Deep eutectic solvents (DESs) became an object of a great interest as an alternative to ionic liquids (ILs) and commonly used in CO2 capture amine solutions. In the present study, five different DESs based on 3-amino-1-propanol as physical-chemical CO2 absorbents were used. The composition was chosen in order to estimate the effects of hydrogen bond acceptor:hydrogen bond donor (HBA:HBD) molar ratio, anion type and length of alkyl chain of composing salt. The Fourier Transform Infrared (FTIR) spectroscopy was used to confirm chemical reaction. The solubility of CO2 was measured at low pressures up to 170 kPa at the temperature range of 293–318 K. Viscosity, polarity and Kamlet–Taft parameters were determined in order to estimate the dependences of the parameters and the CO2 capacity. CO2 uptake was observed to improve with decreasing molar ratio of hydrogen bond donor. Comparing the CO2 capacity of [TBAC]-based DESs, at the approximate pressure of 50 kPa, it was observed that the capacity increased in the following order of molar ratios—1:8 < 1:6 < 1:4 and a decrease in molar ratio from 1:8 to 1:4 resulted in about a 100% increase of capacity. Compared to [TBAC][AP] DESs, the [TEAC][AP] 1:4 and [TBAB][AP] 1:4 exhibited higher CO2 uptake, though the best results were obtained for [TBAB][AP].

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Rossignoli, M., GA Lawrance, M. Maeder, DCR Hockless, BW Skelton, and AH White. "The Influence of Alkyl Substituents on Carbon Acid Formaldehyde Condensation Reactions of Bis(alkane-1,2-diamine)copper(II) Ions." Australian Journal of Chemistry 49, no. 12 (1996): 1307. http://dx.doi.org/10.1071/ch9961307.

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The reaction of the bis (1,2-diamine)copper(II) complexes of ethane-1,2-diamine (en), propane-1,2-diamine ( pn ) and 2-methylpropane-1,2-diamine ( dmen ) with formaldehyde and nitroethane in methanol under basic conditions yields macrocyclic and acyclic condensation products with two or one new -NH-CH2-C(Me)(NO2)-CH2-NH- links introduced respectively between pairs of cis-disposed primary amines, and where the ratio of products is, surprisingly, significantly altered by C-methyl substitution on the parent ethane-1,2-diamine chelate . Under identical reaction conditions, the ratio of acyclic to macrocyclic product varied from 2:3 (en) to 10:1 ( pn ) to 50:1 ( dmen ) as first one methyl and then gem- dimethyl groups are attached to each parent chelate ring. That the reaction is influenced by substituent steric effects is supported by the structural characterization of the zinc-acid reduced and recomplexed acyclic species, which indicates that first ring formation occurs at amine pairs distant from the C-methyl substituents. The μ-chloro-bis (6-methyl-4,8-diazaundecane-2,6,10-triamine) dicopper (II) perchlorate crystallized in the space group C2/ c, a 23.003(6), b 12.641 (3), c 19.120(6) Ǻ, β 127.88(2)°, whereas the (2,6,10-trimethyl-4,8-diazaundecane-2,6,10-triamine)copper(II) perchlorate crystallized in the space group Cc2a, a 43.769(3), b 14.509(3), c 17.750(8) Ǻ. The copper ion is found in a distorted octahedral environment in the former with two complex units weakly bridged by a chloride anion, and in a square-based pyramidal environment in the latter.

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Veltri, Lucia, Bartolo Gabriele, Raffaella Mancuso, Patrizio Russo, Giuseppe Grasso, Corrado Cuocci, and Roberto Romeo. "Palladium-Catalyzed Carbonylative Synthesis of Functionalized Benzimidazopyrimidinones." Synthesis 50, no. 02 (November 23, 2017): 267–77. http://dx.doi.org/10.1055/s-0036-1591835.

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A new and convenient approach to functionalized benzimidazopyrimidinones is reported. It is based on a two-step procedure starting from readily available 1-(prop-2-yn-1-yl)-1H-benzo[d]imidazol-2-amines, consisting of a multicomponent palladium-catalyzed oxidative cyclocarbonylation–alkoxycarbonylation process, followed by base-promoted isomerization of the initially formed mixture of isomeric carbonylated products. Fair to good overall yields of the final alkyl 2-(2-oxo-1,2-dihydrobenzo[4,5]imidazo[1,2-a]pyrimidin-3-yl)acetates are obtained, using different alcohols as solvent and nucleophile in the carbonylation step (carried out in the presence of 0.33–1 mol% PdI2 in conjunction with 17–50 mol% KI, at 100 °C and under 20 atm of a 4:1 mixture of CO–air) and the corresponding sodium alkoxide as base in the subsequent isomerization step (carried out in the alcoholic solvent at room temperature). The structures of a representative substrate [N-benzyl-1-(prop-2-yn-1-yl)-1H-benzo[d]imidazol-2-amine] and a representative product [methyl 2-(1-isopentyl-2-oxo-1,2-dihydrobenzo-[4,5]imidazo[1,2-a]pyrimidin-3-yl)acetate] were confirmed by X-ray diffraction analysis.

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Pulido, Angeles, Ming Liu, Paul Reiss, Anna Slater, Sam Chong, Marc Little, Tom Hasell, Mike Briggs, Andrew Cooper, and Graeme Day. "Towards computer-guided tuning of the crystal packing of porous organic cages." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C667. http://dx.doi.org/10.1107/s2053273314093322.

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Abstract:

Among microporous materials, there has been an increasing recent interest in porous organic cage (POC) crystals, which can display permanent intrinsic (molecular) and extrinsic (crystal network) porosity. These materials can be used as molecular sieves for gas separation and potential applications as enzyme mimics have been suggested since they exhibit structural response toward guest molecules[1]. Small structural modifications of the initial building blocks of the porous organic molecules can lead to quite different molecular assembly[1]. Moreover, the crystal packing of POCs is based on weak molecular interactions and is less predictable that other porous materials such as MOFs or zeolites.[2] In this contribution, we show that computational techniques -molecular conformational searches and crystal structure prediction- can be successfully used to understand POC crystal packing preferences. Computational results will be presented for a series of closely related tetrahedral imine- and amine-linked porous molecules, formed by [4+6] condensation of aromatic aldehydes and cyclohexyl linked diamines. While the basic cage is known to have one strongly preferred crystal structure, the presence of small alkyl groups on the POC modifies its crystal packing preferences, leading to extensive polymorphism. Calculations were able to successfully identify these trends as well as to predict the structures obtained experimentally, demonstrating the potential for computational pre-screening in the design of POCs within targeted crystal structures. Moreover, the need of accurate molecular (ab initio calculations) and crystal (based on atom-atom potential lattice energy minimization) modelling for computer-guided crystal engineering will be discussed.

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Journal articles on the topic 'Alkyl amine based naphthoxazine'

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