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Synthesis, Characterization and Reactivity of Bis(4-tert-butylphenolato)dichlorotin(IV)

100%

Chaudhry S. C. , Bandna K. , Bhatt S. S. , Sharma N.

2009

tom Vol. 83, nr 9

1537-1545

The bis(4-tert-butylphenolato)dichlorotin(IV) complex of composition SnCl2(OC6H4But-4)2 (1) has been synthesized by the reaction of tin tetrachloride with bimolar amount of 4-t-butylphenol in benzene under reflux and characterized by elemental analyses, molar conductance measurements, molecular weight determination, IR, 1H, 13C NMR and FAB mass spectral techniques. Thermal behaviour of the complex has been investigated using TG-DTA technique. Lewis acid character of (1) has been explored by isolating its addition compounds with some nitrogeneous bases viz. diethylamine, triethylamine, imidazole, benzimidazole (L); 2,2'-bipyridyl, and 1,10-phenanthroline (B) of composition, SnCl2(OC6H4But-4)2×2L and SnCl2(OC6H4But-4)2×B, characterized by physicochemical and IR spectral studies.

Growth and characterization of NLO crystal: L-leucine phthalic acid potassium iodide

86%

Jagadeesh M. R. , Kumar H. M. S. , Kumari R. A.

Materials Science Poland

2015

tom Vol. 33, No. 3

529--536

A new semi-organic non linear optical crystal, L-leucine phthalic acid potassium iodide (LLPPI) has been grown from an aqueous solution by slow evaporation method. The grown crystals were subjected to different characterizations, such as single crystal XRD, FT-IR, UV-Vis, TGA, SEM, EDAX, micro hardness, dielectric and powder SHG. Single crystal structure was determined from X-ray diffraction data and it revealed that the crystal belongs to triclinic system with the space group P1. The vibrational frequencies of various functional groups were derived from FT-IR spectrum. Thermal stability of the grown crystal was investigated by TG-DTA studies and it was observed that the crystal was thermally stable up to 192 °C. Optical absorption study was carried out and a good transparency in the entire visible region was observed at the lower cutoff wavelength of 227 nm. Dielectric study was performed as a function of frequency and normal dielectric behavior was observed. The micro hardness test was carried out and the load dependent hardness was measured. Kurtz powder method was employed to explore the NLO characteristics of the grown crystal.

X-ray diffraction and thermo gravimetric analysis of surface modified areca sheath fibre epoxy composites

72%

Chandrappa R. K. , Kamath S. S.

Journal of Mechanical and Energy Engineering

2022

tom Vol. 6, No 2

1--6

Focus of the current study is to shed more light on thermal behaviour of composites made up of areca sheath fibres. The XRD analysis revealed that crystallinity index and crystallinity percentage increased with different treatments, as it leads to better interaction of fibre and resin. The crystallinity percentage of alkali treated fibre and benzoyl peroxide treated fibre increased by 5.87 and 8.44% respectively compared to untreated fibre. This was further evident in thermal studies which proved better thermal stability in benzoyl peroxide treated fibre composite.

Influence of fiber reinforcement towards the physical characteristics of low density polyethylene laminated composites

58%

Ravichandran S. , Raj A. D. , Visvanath P. B. , Mohammad F. , Al-Lohedan H. A. , Sagadevan S.

Polimery

2020

tom T. 65, nr 6

449--457

In recent years, the increased interest in the design and fabrication of lightweight polymer composites with various combinations and stoichiometry is due to their enhancement of electrical, mechanical, thermal, and biological properties compared to the properties of conventional materials. With that view, the present study deals with the effects of low density polyethylene composites (LDPE) reinforced with epoxy resin, glass fiber, carbon fiber, and Kevlar towards the mechanical, thermal, and water absorption properties. The mechanical studies showed that the LDPE composite reinforced carbon fiber has the best tensile properties compared to other composites and this can be mostly due to the proper bonding and associated interaction between the polymeric matrix and the bidirectional layer of the fibers. Also, the carbon fiber reinforced composite has superior properties of impart energy compared to the other composites and the non-reinforced ones and this is attributed to the crystalline nature of carbon fiber. Further studies of the thermal properties indicated that the retention of thermal stability for all the fiber-reinforced polymer composites, while the water absorption revealed a considerable increase in the weight of Kevlar fiber-reinforced composite. From the overall analysis, the enhanced properties of LDPE matrix reinforced fibers are linked to the morphological changes that occurred and are directly affected by the nature of the fiber.

Zwiększone w ostatnich latach zainteresowanie projektowaniem i wytwarzaniem lekkich kompozytów polimerowych wynika z ich lepszych właściwości elektrycznych, mechanicznych, termicznych i biologicznych w porównaniu z cechami materiałów konwencjonalnych. Zbadano wpływ rodzaju wzmocnienia (włókno szklane, włókno węglowe i włókno Kevlar) na właściwości mechaniczne, termiczne i absorpcję wody laminatowych kompozytów polietylenu małej gęstości (LDPE) z żywicą epoksydową. Stwierdzono, że kompozyt LDPE z włóknem węglowym, w porównaniu z innymi kompozytami, wykazuje najlepszą wytrzymałość na rozciąganie, co może wynikać głównie z interakcji polimerowej osnowy z dwukierunkową warstwą włókien. Ponadto kompozyt ten ma większą zdolność przenoszenia energii niż pozostałe badane kompozyty, co można przypisać krystalicznej budowie włókna węglowego. Badania właściwości termicznych wykazały stabilność termiczną wszystkich kompozytów polimerowych wzmocnionych włóknami oraz znaczną absorpcję wody kompozytu wzmocnionego włóknem Kevlar.