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101.
Superior heat‐resistant and oil‐resistant blends based on dynamically vulcanized hydrogenated acrylonitrile butadiene rubber and polyamide 12 下载免费PDF全文
High‐performance thermoplastic vulcanizates (TPVs) are the new generation of TPVs that provide superior heat and oil aging behavior. TPVs based on hydrogenated acrylonitrile butadiene rubber and polyamide 12 (PA12) have been first developed by the dynamic vulcanization process, in which selective cross‐linking of the elastomer phase during melt mixing with the thermoplastic phase (PA12) was carried out simultaneously. In this present investigation, hydrogenated acrylonitrile butadiene rubber (HNBR)/PA12 and partially hydrogenated carboxylated acrylonitrile butadiene rubber (XHNBR)/PA12 with blend ratio of 50:50, 60:40, and 70:30 wt% were prepared at 185°C at a rotor speed of 80 rpm for 5 min. Di‐(2‐tert‐butyl peroxy isopropyl) benzene was chosen as the suitable cross‐linking peroxide to pursue the dynamic vulcanization. TPV based on 50:50 HNBR/PA12 and XHNBR/PA12 show better physico‐mechanical properties, rheological behavior, thermal stability, dynamic mechanical analysis, and creep behavior among all the TPVs. Morphology study reveals that dispersed phase morphology has been formed with an average dimension of the rubber particles in the range of 0.8–1.5 µm. For aging test, TPVs were exposed to air and ASTM oil 3, respectively. Air aging tests were carried out in hot air oven for 72 hr at 125°C, while the oil aging tests were carried out after immersion of the samples into the oils in an aging oven. After aging, there is only slight deterioration in the physico‐mechanical properties of the TPVs. In case of 50:50 blends of HNBR/PA12 and XHNBR/PA12, the retention of the properties upon after aging was found excellent. These TPVs are designed to find potential application in automotive sector especially for under‐hood‐application, where high‐temperature resistance as well as high oil resistance is of prime importance. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
102.
Sumita NaskarSubhendu Naskar Heike Mayer-FiggeWilliam S. Sheldrick Shyamal Kumar Chattopadhyay 《Polyhedron》2011,30(3):529-534
Two mononuclear Cu(II) complexes, [Cu(L1H2)](ClO4)1.25Cl0.75·1.25H2O (1) and [Cu(L2H2)](ClO4)2 (2), of the pyridoxal Schiff base ligands N,N′-dipyridoxylethylenediimine (L1H2) and N,N′-dipyridoxyl-1,3-propanediimine (L2H2) are reported. X-ray crystal structures of both complexes are also reported. In both complexes the pyridoxal nitrogen atoms remain protonated. In the solid state, the tetradentate Schiff base ligand is virtually planar in 1, while in 2 the ligand conformation is like an inverted umbrella. In cyclic voltammetry experiments it is found that in these complexes the Cu(III) and Cu(I) states are more easily accessible than in their salen type analogs. The pyridoxal Schiff base complexes are also found to be resistant to oxidative electro-polymerization, unlike their corresponding salicyl aldehyde Schiff base complexes. 相似文献
103.
Cheng-Zong Kuo Li-Yun Hsu Yu-Shan Chen Dr. Kenta Goto Dr. Subhendu Maity Dr. Yi-Hung Liu Prof. Shie-Ming Peng Dr. Kien Voon Kong Prof. Teruo Shinmyozu Prof. Jye-Shane Yang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(50):11511-11521
Anthracene–pentiptycene hybrid systems 1-Cn , where n refers to the number of carbon atoms in the linear alkyl chain, crystallize in three different polymorphs, denoted Y (yellow), G (green), and B (blue) forms in terms of the fluorescence color. While all Y-form crystals show the same yellow-to-blue fluorescence color response to the photomechanical stress generated by the anthracene [4+4] photodimerization reaction, the four G forms exhibit distinct photomechanofluorochromism (PMFC): from green to blue for G-1-C4 , to orange for G-1-C7 , to red for G-1-C8 , and to red then blue for G-1-C9 , and the B forms show no photochromic activity. The intriguing RGB three-color PMFC and abnormal topochemical reactivity of G-1-C9 are attributed to inherent softness of the crystal lattice. 相似文献
104.
Mondal Animesh Naskar Barnali Goswami Sanchita Prodhan Chandraday Chaudhuri Keya Mukhopadhyay Chhanda 《Molecular diversity》2020,24(1):93-106
Molecular Diversity - A quick access tool for the one-pot, chromatography-free synthesis of the diversified dihydrospiro[indeno[1,2-b]pyridine-4,3′-indoline or... 相似文献
105.
Ravi Dhas C. Jennifer Christy A. Venkatesh R. Panda Subhendu K. Subramanian B. Ravichandran K. Sudhagar P. Moses Ezhil Raj A. 《Journal of Solid State Electrochemistry》2018,22(8):2485-2497
Journal of Solid State Electrochemistry - The influence of solvent volume on the properties of CuInAlS2 (CIAS) thin films deposited using simple and cost-effective nebulizer spray technique is... 相似文献
106.
107.
Subhendu Naskar Dipankar Mishra Alexander J. Blake Shyamal K. Chattopadhyay 《Structural chemistry》2007,18(2):217-222
Anthraniloyl hydrazide (AH) contains two −NH2 groups, one of them is attached to the aromatic ring and the other is the hydrazinic, −NH2. It is found that only the later reacts with the carbonyl compounds to form Schiff bases, while the former remains inert.
The reasons behind this difference in reactivity are analyzed on the basis of semi-empirical calculations, which show that
the lone pair of the ring −NH2 is considerably delocalized over the ring, resulting in an accumulation of a positive charge on this particular nitrogen.
Ni(II) complex of 2,6-diacetylpyridine bis(anthraniloyl hydrazone) has been prepared and characterized by various physico-chemical
methods. The structure of the complex was determined by X-ray crystallography. It was found that in the solid state, the compound
exist as a dimer, and two coordinated ligand moieties form a double helix around the two metal ions. H-bonding then results
in extension of double helix to an infinite chain. 相似文献
108.
Dinabandhu Naskar Amrita RoyWilliam L. Seibel David E. Portlock 《Tetrahedron letters》2003,44(49):8865-8868
An efficient synthesis of N-hydroxy or alkoxy-α-aminocarboxylic acids and N-(tert-butyl sulfinyl)-α-amino carboxylic acids has been developed from N,O-alkyl or hydroxylamines and tert-butyl sulfinamide utilizing a Petasis boronic acid-Mannich reaction. The scope and limitations of this method have been examined. 相似文献
109.
Preparation of (6RS)Tetra- and (6RS)-Pentaacetyl-5,6,7,8-tetrahydro-L-biopterines Boiling of (6RS) l′-O,2′-O,2-N-triacetyl-5,6,7,8-tetrahydro-L-biopterine in acetic anhydride as described in [2], leads to a mixture of the diastereoisomeric (6R)- and (65)-l′-O,2′-O,2-N-,5,8-pentaacetyl-5,6,7,8-L,-biopterines. One of the diastereoisomers can be obtained as pure crystals. It corresponds to the pentaacetate of the natural (6R)- or (6S).,5,6,7,8-tetrahydro-L-biopterine. For the preparation of the earlier described (6RS)- and (6S)-tetraacetyl-tetrahydro-L-biopterines [2] improved conditions are reported. 相似文献
110.
Sipra Naskar 《Tetrahedron letters》2007,48(3):465-467
[(PPh3)2Ru(CH3CN)3Cl][BPh4] has been found to catalyze the selective reduction of double bonds in α,β-unsaturated ketones with high conversions when formic acid is the hydrogen donor. 相似文献