scholarly journals Non-isothermal crystallization of LiNaGe4O9 glass

2021 ◽  
Vol 29 (1) ◽  
pp. 73-76
Author(s):  
Ye. V. Skrypnik ◽  
M. P. Trubitsyn ◽  
A. O. Diachenko ◽  
M. D. Volnianskii
Keyword(s):  
Differential Scanning Calorimetry ◽  
Glass Transition ◽  
Glass Structure ◽  
Exothermic Peak ◽  
Gravimetric Analysis ◽  
Thermal Gravimetric ◽  
Glass Crystallization ◽  
Scanning Calorimetry ◽  
Noticeable Increase ◽  
Characteristic Temperatures

The glass of lithium-sodium tetragermanate LiNaGe4O9 is crystallized on heating under the control of differential scanning calorimetry and thermal gravimetric analysis. The measurements were prepared in the temperature range 300-870 K and showed the relatively weak endothermic DSC anomaly and 40-50 K above the single exothermic peak. The endothermic anomaly observed at Tg testified to softening the glass structure whereas the exothermic peak at TC manifested crystallization of the amorphous phase. Studying of TGA demonstrated smooth nearly linear dependences without any visible anomalies. Varying the heating rate from 1.2 up to 40 K/min resulted in noticeable increase of the characteristic temperatures Tg and TC. Lower limit of the glass transition temperature Tg0 was estimated with the help of the existing model. The mechanism of the LiNaGe4O9 glass crystallization is discussed.

scholarly journals Thermal analysis of Li2-хNaxGe4O9 glasses crystallization

2020 ◽  
Vol 28 (2) ◽  
pp. 83-86
Author(s):  
A. O. Diachenko ◽  
D. V. Volynets ◽  
M. P. Trubitsyn ◽  
M. D. Volnianskii
Keyword(s):  
Thermal Analysis ◽  
Solid Solution ◽  
Differential Scanning Calorimetry ◽  
Thermal Gravimetric Analysis ◽  
Single Stage ◽  
Gravimetric Analysis ◽  
Thermal Gravimetric ◽  
Glass Crystallization ◽  
Scanning Calorimetry ◽  
Dsc Measurements

The glasses of lithium-sodium tetragermanate LiNaGe4O9 and solid solution Li1.8Na0.2Ge4O9 were prepared by quenching the melt and crystallized on heating. The glass crystallization was controlled by differential scanning calorimetry and thermal gravimetric analysis. The DSC measurements performed in the range 300–1200 K show that the crystallization of the glasses occurs through a single stage. There are no anomalies on TGA dependences. It is assumed that LiNaGe4O9 and Li 1.8Na0.2Ge4O9 glasses crystallize in accordance with a polymorphic mechanism.

Synthesis, Characterization and Application of Multi-Generations Hyperbranched Polyurethane Based on Isophorone Diisocyanate

2012 ◽  
Vol 554-556 ◽  
pp. 126-129 ◽  
Author(s):  
Shun Yin ◽  
Ning Sun ◽  
Chun Yun Feng ◽  
Zhi Mou Wu ◽  
Zhao Hua Xu ◽  
...  
Keyword(s):  
Differential Scanning Calorimetry ◽  
Raw Materials ◽  
Degradation Mechanism ◽  
Resonance Spectroscopy ◽  
Gravimetric Analysis ◽  
Thermal Gravimetric ◽  
Isophorone Diisocyanate ◽  
Scanning Calorimetry ◽  
Degradation Temperature ◽  
Hyperbranched Polyurethane

A series of different generation hyperbranched polyurethane(HBPU) was synthesized based on the raw materials of isophorone diisocyanate(IPDI) and diethanolamine(DEOA). Their structure, thermal degradation mechanism and glass transition temperature(Tg) were characterized by fourier transform infrared spectroscopy(FTIR), nuclear magnetic resonance spectroscopy(NMR), thermal gravimetric analysis(TGA) and differential scanning calorimetry(DSC). The results showed that: the yield of each generation HBPU was up to 90%, different generation HBPU had almost the same initial degradation temperature(about at 200°C) and they all had two decomposition platforms; with the increase of generation, Tg increased from 107.2°C to 132.1°C. The gloss and hardness of the HBPU coatings were significantly improved.

Preparation of Two Novel Ionic Electroconductive Polyurethanes Functionalized with the Backbone of Ionic Liquid

2013 ◽  
Vol 668 ◽  
pp. 259-262
Author(s):  
Ding Jun Zhang ◽  
Chao Yun Qu ◽  
Yu Xian Chen
Keyword(s):  
Electrical Conductivity ◽  
Differential Scanning Calorimetry ◽  
Ionic Liquid ◽  
Surface Resistance ◽  
High Yield ◽  
Gravimetric Analysis ◽  
Thermal Gravimetric ◽  
Facile Synthesis ◽  
Scanning Calorimetry ◽  
Structures And Properties

The facile synthesis of two new Ionic electroconductive polyurethanes with the framework of ionic liquids, i.e., PUR-T: synthesized with isocyanate TDI; PUR-H: synthesized with isocyanate HDL, are described. Their structures and properties were characterized by Fourier transform infrared spectroscopy (FTIR), thermal gravimetric analysis (TGA), Differential scanning calorimetry (DSC) and the surface resistance meter. The effects of the different kinds of isocyanate on electrical conductivity of PUR were also investigated. It was found that their electrical conductivity can be optimized by changing the reaction temperature. The PUR-H, which exhibits an electrical conductivity of 1.0×104 Ω surface resistance, could be obtained in high yield, up to 65% at 90 oC for 12h.

Pad Degradation During CMP Process: Effect of Soak in Slurry and Water on Thermal and Mechanical Properties of the CMP Pads

2003 ◽  
Vol 767 ◽  
Author(s):  
A. Tregub ◽  
G. Ng ◽  
M. Moinpour
Keyword(s):  
Mechanical Properties ◽  
Differential Scanning Calorimetry ◽  
Thermal Gravimetric Analysis ◽  
Mechanical Analysis ◽  
Gravimetric Analysis ◽  
Thermal And Mechanical Properties ◽  
Thermal Gravimetric ◽  
Scanning Calorimetry ◽  
Modulated Differential Scanning Calorimetry ◽  
Thermal Mechanical Analysis

AbstractSoak of polyurethane-based CMP pads in tungsten slurry and de-ionized water and its effect on retention of thermal and mechanical properties of the pads was studied using Dynamic Mechanical Analysis (DMA), Thermal Mechanical Analysis (TMA), Thermal Gravimetric Analysis (TGA), and Modulated Differential Scanning Calorimetry (MDSC). Simultaneous cross-linking and plastisizing due to soak were established using DMA and MDSC analysis. The stable operating temperature range and its dependence on soak time were determined using TMA analysis. Substantial difference in diffusion behavior of the “soft” and “hard” pads was discovered: diffusion into the hard pads followed Fickian law [1], while diffusion into the multi-layer soft pads was dominated by the fast filling of the highly porous pad surface with liquid.During a traditional CMP process, which involves application of polishing pads and slurry, the pad properties can be substantially and irreversibly changed as the result of slurry/rinse water absorption.The retention of the pad properties after exposure was monitored using such thermal and mechanical techniques, as Thermal Mechanical Analysis (TMA), Dynamical Mechanical Analysis (DMA), Modulated Differential Scanning Calorimetry (MDSC), Thermal Gravimetric Analysis (TGA).

scholarly journals ENCAPSULATION LAVENDER OIL BY SPRAY DRYING FOR SPORTSWEAR

2021 ◽  
Vol 2021 ◽  
pp. 148-154
Author(s):  
G. Erkan ◽  
G.C. Türkoğlu ◽  
S.Y. Karavana ◽  
A.M. Sariişik ◽  
B. Ütebay ◽  
...  
Keyword(s):  
Differential Scanning Calorimetry ◽  
Spray Drying ◽  
Textile Industry ◽  
Gravimetric Analysis ◽  
Thermal Gravimetric ◽  
Drying Method ◽  
Scanning Calorimetry ◽  
Lavender Oil ◽  
Wall Materials ◽  
Controlled Released

Microencapsulation technology has been increasingly used in textile industry due to give some peculiarities such as controlled released etc. In this study we aim to make aromatherapy sportswear using lavender oil. Lavender oil is encapsulated by different wall materials. Microcapsules were obtained by spray drying method. Differential scanning calorimetry, thermal gravimetric analysis, Fourier Transform infrared spectroscopy, morphological analyses were applied to microcapsules. Optimum microcapsules were applied to different fabrics. Fastness to washing and rubbing, SEM and antibacterial tests were carried out.

Sequential Modification of ADMET Polyketone via Oxime Chemistry and Electrophilic Alkoxyetherification

2018 ◽  
Vol 71 (6) ◽  
pp. 449 ◽  
Author(s):  
Fu-Rong Zeng ◽  
Qi-Lin Zhu ◽  
Zi-Long Li
Keyword(s):  
Thermal Stability ◽  
Differential Scanning Calorimetry ◽  
Thermal Properties ◽  
Functional Polymers ◽  
Gravimetric Analysis ◽  
Acyclic Diene Metathesis ◽  
Thermal Gravimetric ◽  
Complete Conversion ◽  
Scanning Calorimetry ◽  
Admet Polymerization

Post-polymerization modification is a facile and efficient method for the generation of diverse functional polymers. Herein, polymer-based molecular arrays were obtained by using sequential modification. First, periodic polyketone P0 was synthesized via acyclic diene metathesis (ADMET) polymerization of α,ω-diene M0. Oxime chemistry was employed in the functionalization of the ketone moieties of P0 using three commercially available alkoxyamine hydrochlorides. Finally, electrophilic alkoxyetherification, a four-component reaction, was employed in the modification of alkene groups on polymer main chains using N-bromosuccinimide (NBS), tetrahydrofuran, and fluorinated carboxylic acid. Complete conversion of reactive sites was observed in both steps, and the two modification reactions exhibited excellent compatibility. The thermal properties of the polymers as thermal stability, and glass transition and melting behaviours were investigated by thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC).

The use of bisfuroic acid derivatives in the curing of bismaleimides

1994 ◽  
Vol 6 (3) ◽  
pp. 249-256 ◽  
Author(s):  
D G Hawthorne ◽  
J H Hodgkin ◽  
M B Jackson ◽  
T C Morton
Keyword(s):  
Thermal Stability ◽  
Differential Scanning Calorimetry ◽  
Thermal Behaviour ◽  
Thermal Gravimetric Analysis ◽  
Diels Alder ◽  
Gravimetric Analysis ◽  
Resin System ◽  
Thermal Gravimetric ◽  
Scanning Calorimetry ◽  
Thermal Stability Of

The use of 2,2-bis(4-[(2-carboxy-5-furyl)oxy]phenyl)propane as a Diels-Alder based co-reactant for curing bismaleimides was investigated. Differential scanning calorimetry and thermal gravimetric analysis were used to study the thermal behaviour of this reactant on its own and in the presence of 1,1'-(4methylene-4,1-phenylene)bismaleimide. The range of products formed under different cure conditions was determined by vFnR spectroscopy. The DMTA characteristics and thermal stability of cured laminates made from this resin system have been investigated. It is concluded that the thermal stability and other properties of laminates made from this system are only comparable to those of a typical commercial bismaleimide system.

Studies on bismaleimides and related materials: Part III. Synthesis and characterization of bismaleimiides derived from benzophenone, 1, 2-diphenylethane, 1, 4-diphenylbutane and condensed pyrazines

1994 ◽  
Vol 6 (1) ◽  
pp. 35-41
Author(s):  
P N Prestont ◽  
V K Shaht ◽  
S W Simpsont ◽  
I Soutar ◽  
N J Stewart
Keyword(s):  
Thermal Analysis ◽  
Differential Scanning Calorimetry ◽  
Oxidative Stability ◽  
Thermal Gravimetric Analysis ◽  
Dynamic Mechanical Thermal Analysis ◽  
Synthesis And Characterization ◽  
Gravimetric Analysis ◽  
Thermal Gravimetric ◽  
Scanning Calorimetry

New bismaleimides have been synthesised from diamines derived from benzophenone, 1,2-diphenylethane, 1,4-diphenylbutane, 2, 3-diphenylquinoxaline and 2, 3-diphenylnaphtho[2, 3-b]pyrazine. Cure profiles have been established by both differential scanning calorimetry (Dsc) and dynamic mechanical thermal analysis (DMTA). Cured resins prepared from the bismaleimide monomers were studied by thermal gravimetric analysis (TGA) with all materials exhibiting good thermal and thermo-oxidative stability.

Effect of tensile stress on the annealed structure of a metallic glass

1987 ◽  
Vol 2 (4) ◽  
pp. 461-470 ◽  
Author(s):  
P. T. Vianco ◽  
J. C. M. Li
Keyword(s):  
Heat Treatment ◽  
Differential Scanning Calorimetry ◽  
Glass Transition ◽  
Tensile Stress ◽  
Room Temperature ◽  
Exothermic Peak ◽  
Scanning Calorimetry ◽  
Disordered Structure ◽  
Heat Treated ◽  
Dsc Thermograms

The low-temperature (120°–245°C) structural relaxation of Metglas¯ 2826B (Ni49Fe29P14B6Si2) amorphous alloy was investigated for samples subjected to a tensile stress in the range of 20–400 MPa during annealing. The stress-annealed samples demonstrated a much smaller increase of microhardness than was observed in similarly annealed ribbons without a stress. Further heat treatment of the stress-annealed specimens, this time without the stress, was capable of increasing the microhardnesses of only some ribbons to values equal to those of samples similarly heat treated initially without a stress. An additional exothermic peak in the differential scanning calorimetry (DSC) thermograms of the stress-annealed specimens indicated the presence of a more disordered structure at room temperature, which was found to correlate with the lower microhardness values. Otherwise, those artifacts of the DSC thermograms that were characteristic of samples annealed without a stress were still present in the stress-annealed ribbons. No effect on the crystallization temperature was noted but the glass transition temperature was increased in the stress-annealed case with respect to values attained when the stress was absent during heat treatment. A reduction in the degree of embrittlement of those samples annealed with a tensile stress was a further indication of more disorder in the stress-annealed ribbons.

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