Thermometric Studies of Newly Developed Nanolubricants

2016 ◽  
Author(s):  
Sayavur I. Bakhtiyarov ◽  
Elguja R. Kutelia ◽  
Dennis A. Siginer
Keyword(s):  
Storage Capacity ◽  
Heat Storage ◽  
Vapor Pressures ◽  
Scanning Calorimetry ◽  
Modulated Differential Scanning Calorimetry ◽  
Flow Measurements ◽  
Heat Transfer Fluids ◽  
Large Heat ◽  
New Space ◽  
Space Vacuum

One of the primary requirements of space lubricants is that they have extremely low vapor pressures to withstand the space vacuum environment. Nanolubricants are known to have extremely low vapor pressure and some have attractive lubricant properties such as low coefficient of friction and good lifetimes. However, many other physical properties need to be evaluated in bringing forth new space liquid lubricants such as wide liquid temperature range and adequate heat transmission capabilities. The heat capacity and heat flow measurements for two newly developed nanolubricants Kolkhida 1 and Kolkhida 2 were conducted using Modulated Differential Scanning Calorimetry (MDSC). The experimental results revealed that the tested ionic liquids have large heat storage capacity as compare to the conventional heat transfer fluids.

Novel facile self-assembly approach to construct graphene oxide-decorated phase-change microcapsules with enhanced photo-to-thermal conversion performance

2018 ◽  
Vol 6 (10) ◽  
pp. 4535-4543 ◽  
Author(s):  
Kunjie Yuan ◽  
Jian Liu ◽  
Xiaoming Fang ◽  
Zhengguo Zhang
Keyword(s):  
Graphene Oxide ◽  
Phase Change ◽  
Self Assembly ◽  
Storage Capacity ◽  
Heat Storage ◽  
Thermal Conversion ◽  
Thermal Reliability ◽  
Encapsulation Rate ◽  
Large Heat ◽  
Conversion Performance

Novel self-assembled phase change microcapsule exhibits high encapsulation rate, large heat storage capacity, good thermal reliability and enhanced photo-thermal performance.

Thermal Behaviour of New Type of Plaster with PCM Admixture

2015 ◽  
Vol 710 ◽  
pp. 3-7 ◽  
Author(s):  
Jan Fořt ◽  
Milena Pavlíková ◽  
Anton Trník ◽  
Zbyšek Pavlík
Keyword(s):  
Differential Scanning Calorimetry ◽  
Indoor Environment ◽  
Storage Capacity ◽  
Heat Storage ◽  
Laser Diffraction ◽  
Scanning Calorimetry ◽  
Matrix Density ◽  
New Type ◽  
Change Material

In order to decrease the energy consumption of buildings and keep the high thermal comfort of the indoor environment, new types of plasters modified by phase change material (PCM) are developed and experimentally tested. For evaluation of the contribution of PCM admixture to plasters properties, the reference plaster is studied as well. The basic characterization of the tested plasters is done using the measurement of their bulk density, matrix density a total open porosity. For the dry plasters mixtures, the particle size distribution is accessed on laser diffraction principle. Investigation of thermal properties as main parameters affecting the thermal performance of researched materials is done by differential scanning calorimetry (DSC) and transient impulse method. The obtained results proved increased heat storage capacity of the newly developed plasters with incorporated PCM admixture.

Preparation and Properties of Polyacrylonitrile / Binary of Fatty Acids Composites as Phase Change Fibers

2011 ◽  
Vol 239-242 ◽  
pp. 1199-1202 ◽  
Author(s):  
Jing Guo ◽  
Heng Xue Xiang ◽  
Xue Yong Gong ◽  
Qian Qian Wang
Keyword(s):  
Fatty Acids ◽  
Phase Change ◽  
Latent Heat ◽  
Storage Capacity ◽  
Heat Storage ◽  
Breaking Strength ◽  
Scanning Calorimetry ◽  
Latent Heat Storage ◽  
Hot Air ◽  
Spinning Process

With stearic acid/lauric acid binary of fatty acids as phase change material, polyacrylonitrile (PAN) as framework material, PAN/ binary of fatty acids phase change fibers is prepared by wet spinning process. Morphology and latent heat storage capacity of phase change fibers are investigated using microscope, scanning electron microscope (SEM) and differential scanning calorimetry (DSC), respectively. Influences of the ratio of PAN/ binary of fatty acids, concentration of the coagulation and spinning liquid on breaking strength have been studied by yarn strength tester. The results show that breaking strength of phase change fiber dried at 110°C hot air is higher than that of dried at room temperature, the breaking strength of PAN/ binary of fatty acids fiber increases with the increment of the ratio of PAN/ binary of fatty acids, concentration of the coagulation and spinning liquid. The latent heat storage capacity of phase change fiber has reached 18J/g, the phase transition temperature is about 28.6°C.

scholarly journals Synthesis and Polymerization Kinetics of Rigid Tricyanate Ester

Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1686
Author(s):  
Andrey Galukhin ◽  
Roman Nosov ◽  
Ilya Nikolaev ◽  
Elena Melnikova ◽  
Daut Islamov ◽  
...  
Keyword(s):  
Kinetic Analysis ◽  
Single Step ◽  
Polymerization Kinetics ◽  
Scanning Calorimetry ◽  
Modulated Differential Scanning Calorimetry ◽  
Diffusion Controlled ◽  
Polymerization Product ◽  
The One ◽  
Kinetics Of

A new rigid tricyanate ester consisting of seven conjugated aromatic units is synthesized, and its structure is confirmed by X-ray analysis. This ester undergoes thermally stimulated polymerization in a liquid state. Conventional and temperature-modulated differential scanning calorimetry techniques are employed to study the polymerization kinetics. A transition of polymerization from a kinetic- to a diffusion-controlled regime is detected. Kinetic analysis is performed by combining isoconversional and model-based computations. It demonstrates that polymerization in the kinetically controlled regime of the present monomer can be described as a quasi-single-step, auto-catalytic, process. The diffusion contribution is parameterized by the Fournier model. Kinetic analysis is complemented by characterization of thermal properties of the corresponding polymerization product by means of thermogravimetric and thermomechanical analyses. Overall, the obtained experimental results are consistent with our hypothesis about the relation between the rigidity and functionality of the cyanate ester monomer, on the one hand, and its reactivity and glass transition temperature of the corresponding polymer, on the other hand.

scholarly journals Manipulation of the Glass Transition Properties of a High-Solid System Made of Acrylic Acid-N,N′-Methylenebisacrylamide Copolymer Grafted on Hydroxypropyl Methyl Cellulose

2021 ◽  
Vol 22 (5) ◽  
pp. 2682
Author(s):  
Nazim Nassar ◽  
Felicity Whitehead ◽  
Taghrid Istivan ◽  
Robert Shanks ◽  
Stefan Kasapis
Keyword(s):  
Glass Transition ◽  
Acrylic Acid ◽  
Methyl Cellulose ◽  
Small Deformation ◽  
Polymerization Reaction ◽  
Solid Matrix ◽  
Scanning Calorimetry ◽  
Modulated Differential Scanning Calorimetry ◽  
High Solid ◽  
Hydroxypropyl Methyl Cellulose

Crosslinking of hydroxypropyl methyl cellulose (HPMC) and acrylic acid (AAc) was carried out at various compositions to develop a high-solid matrix with variable glass transition properties. The matrix was synthesized by the copolymerisation of two monomers, AAc and N,N′-methylenebisacrylamide (MBA) and their grafting onto HMPC. Potassium persulfate (K2S2O8) was used to initiate the free radical polymerization reaction and tetramethylethylenediamine (TEMED) to accelerate radical polymerisation. Structural properties of the network were investigated with Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), modulated differential scanning calorimetry (MDSC), small-deformation dynamic oscillation in-shear, thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). The results show the formation of a cohesive macromolecular entity that is highly amorphous. There is a considerable manipulation of the rheological and calorimetric glass transition temperatures as a function of the amount of added acrylic acid, which is followed upon heating by an extensive rubbery plateau. Complementary TGA work demonstrates that the initial composition of all the HPMC-AAc networks is maintained up to 200 °C, an outcome that bodes well for applications of targeted bioactive compound delivery.

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