scholarly journals Fabrication and characterization of conductive microcapsule containing phase change material

e-Polymers ◽  
2019 ◽  
Vol 19 (1) ◽  
pp. 519-526
Author(s):  
Hao-Ran Yun ◽  
Chun-Lei Li ◽  
Xing-Xiang Zhang
Keyword(s):  
Phase Change ◽  
Phase Change Materials ◽  
Thermo Gravimetric Analysis ◽  
Gravimetric Analysis ◽  
Scanning Calorimetry ◽  
Fourier Transformed Infrared Spectroscopy ◽  
Microencapsulated Phase Change Materials ◽  
Structure Morphology ◽  
Latent Heats

AbstractMicroencapsulated phase change materials (MicroPCMs) were fabricated using n-octadecane as PCM and melamine-formaldehyde as shell via in situ polymerization. They were coated with polypyrrole (PPy) to fabricate conductive microcapsules. The structure, morphology, thermal properties and the electrical conductivity of the microcapsules were characterized using the scanning electron microscope (SEM), the Fourier transformed infrared spectroscopy (FTIR), the thermo gravimetric analysis (TGA), the differential scanning calorimetry (DSC) and the standard four-probe method. The results show that, n-octadecane is well encapsulated in rough and compact spherical composites. The melting and freezing the composites latent heats are 90.2 and 92.0 J/g, respectively, while the mass percentage of the n-octadecane in the composites is 49.7%. The melting and crystallizing peak temperature of PPy/MicroPCMs is 24.6°C and 17.9°C, respectively. The addition of PPy improves the thermal stability of the composites. The conductivity of the PPy/MicroP-CMs increases from 0.1 S‧cm–1 to 0.33 S‧cm–1 as the PPy concentration increases from 3 to 10 wt%.

Preparation and Characterization of Tetradecanol Microcapsule Phase Change Materials by Emulsion Polymerization

2015 ◽  
Vol 1089 ◽  
pp. 137-141 ◽  
Author(s):  
Xiao Qiu Song ◽  
Long Di Cao ◽  
Dan Dan Xu
Keyword(s):  
Phase Change ◽  
Phase Change Materials ◽  
Gravimetric Analysis ◽  
Scanning Calorimetry ◽  
Good Thermal Stability ◽  
Result Show ◽  
Ft Ir ◽  
Latent Heats ◽  
Test Result

In this study, it was aimed at preparing and characterizating of poly (methyl methacrylate) (PMMA) shell microcapsules containing tetradecanol as phase change materials (PCMs) for thermal energy storage. The tetradecanol microcapsules were characterized by using scanning electron microscopy (SEM), fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). The test result show that the contents of tetradecanol in microcapsules nearly 57.5% and the latent heats of melting and freezing were found to be 120.7 and 118.4 J/g. TGA analyses also indicated that the microPCMs degraded in two steps and have good thermal stability.

Preparation of Microencapsulated Phase Change Materials Using Surface Modification Method

2014 ◽  
Vol 902 ◽  
pp. 52-57
Author(s):  
Jin Hua Zhu ◽  
Qing Zhen Wen ◽  
Chao Yu ◽  
Xiong Wei ◽  
Li Qing Zhou
Keyword(s):  
Particle Size ◽  
Surface Modification ◽  
Phase Change ◽  
Phase Change Materials ◽  
Core Material ◽  
Particle Analysis ◽  
Gravimetric Analysis ◽  
Microencapsulated Phase Change Materials ◽  
Modification Method ◽  
Core Materials

With the adoption of surface modification method, microencapsulated phase change materials (MEPCM) with polyurea as wall materials, paraffin as core materials were successfully prepared. This paper made a research on the effect dosage of modifier might have on the content of microcapsule core materials. Findings indicated that the content of microcapsule core materials was relatively high as the dosage of modifier being core material 10 wt%. It was preliminarily proved that polyurea had been coated on the surface of paraffin particles by adopting Fourier Transform Infrared Spectrum (FTIR) to formulate the composition and structure of microcapsules. And the laser particle analysis declared that particle size distribution of microcapsules was narrow with average particle size of 389 μm. Thermo Gravimetric Analysis (TG) and Differential Scanning Calorimetry (DSC) were also employed to make a representation of the thermal properties of microcapsules, and it was shown that microcapsules were of wonderful phase change performance and thermal stability.

Microencapsulated Phase Change Materials and its Application in Thermal-Regulated Fibers

2012 ◽  
Vol 519 ◽  
pp. 6-9 ◽  
Author(s):  
Wei Li ◽  
Xing Xiang Zhang ◽  
Xue Chen Wang
Keyword(s):  
Phase Change ◽  
Phase Change Materials ◽  
Formaldehyde Resin ◽  
Dsc Analysis ◽  
Melamine Formaldehyde ◽  
Scanning Calorimetry ◽  
The Core ◽  
Microencapsulated Phase Change Materials ◽  
Spinning Process ◽  
Alginate Fiber

The phase change materials (PCMs) can absorb, store or release large latent heat over a defined temperature range while the materials change phase or state, so they can be potentially used in thermal energy storage. In this paper, a series of microencapsulated phase change materials (MicroPCMs) with n-octadecane and n-dodecanol as core were successfully fabricated respectively, where the styrene-based copolymer, acrylic based copolymer, melamine-formaldehyde resin and polyurea were selected as shell materials. The morphology of these MicroPCMs was observed by scanning electron microscopy (SEM), and the core-shell structure and the shell thickness of microcapsules were also characterized by SEM. In addition, the phase change properties of MicroPCMs were investigated using differential scanning calorimetry (DSC) analysis. Furthermore, thermal-regulated calcium alginate fiber was produced by adding MicroPCMs in wet-spinning process; and the effects of various types of MicroPCMs on fiber was discussed.

Fabrication of Thermochromatic Microencapsulated Phase Change Materials

2011 ◽  
Vol 332-334 ◽  
pp. 1856-1859
Author(s):  
Xiao Hua Liao ◽  
Hai Feng Shi ◽  
Nan Song ◽  
Xing Xiang Zhang
Keyword(s):  
Molecular Structure ◽  
Differential Scanning Calorimetry ◽  
Chemical Structure ◽  
Phase Change Materials ◽  
In Situ Polymerization ◽  
Melamine Formaldehyde ◽  
Scanning Calorimetry ◽  
Microencapsulated Phase Change Materials ◽  
Structure Properties

Microencapsulated n-octadecane (MicroC18) and doped with thermochromatic powders (TC-MicroC18) were prepared with melamine-formaldehyde (M-F) resin as the wall via in-situ polymerization. The chemical structure and thermal behavior of microcapsules were investigated using fourier transform infrared spectroscopy (FTIR), and differential scanning calorimetry (DSC). Experimental results show that 63 wt% n-C18 has been incorporated into microcapsules, and the obvious thermochromatic effect of TC-MicroC18 is displayed with temperature changing. The structure-properties of TC-MicroC18 also is discussed in detail from the aspect of molecular structure.

Enhanced Thermal Conductivity of Phase Change Materials Modified by Exfoliated Graphite Nanoplatelets

2009 ◽  
Vol 1218 ◽  
Author(s):  
Jinglei Xiang ◽  
Lawrence Drzal
Keyword(s):  
Thermal Conductivity ◽  
Phase Change ◽  
Phase Change Materials ◽  
Particle Orientation ◽  
Exfoliated Graphite ◽  
Critical Parameters ◽  
Gravimetric Analysis ◽  
Graphite Nanoplatelets ◽  
Scanning Calorimetry ◽  
Exfoliated Graphite Nanoplatelets

AbstractComposite phase change materials (PCM) were prepared by mixing exfoliated graphite nanoplatelets (xGnP) into paraffin wax. The two types of graphite nanoplatelets that were investigated were xGnP-1 having thickness of 10 nm and a diameter of 1 um and xGnP-15 having the same thickness with a platelet diameter of 15 um. Direct casting and two roll milling were used to prepare samples. Scanning electron microscopy images show that the nanofillers disperse very well in paraffin matrix without noticeable agglomeration. Paraffin/xGnP-15 PCM consistently exhibited higher thermal conductivity than xGnP-1 PCM. The improvement in thermal conductivity was as high as 5 fold for xGnP-15 composites and 2 fold for xGnP-1 composites at 4 vol%. The aspect ratio, particle orientation, and interface density between the conductive particles and the polymer matrix were found to be the critical parameters in determining the conductivities of the resulting nanocomposites. The thermal physical properties of the nanocomposites were investigated by differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). It was found that the latent heat of nanocomposites was not negatively affected in the presence of xGnP particles and the thermal stability improved.

Fabrication and Properties of Microencapsulated-Paraffin/Gypsum-Matrix Building Materials for Thermal Energy Storage

2012 ◽  
Vol 427 ◽  
pp. 45-50 ◽  
Author(s):  
Jun Feng Su ◽  
Sheng Bao Wang
Keyword(s):  
Phase Change ◽  
Building Materials ◽  
Phase Change Materials ◽  
In Situ Polymerization ◽  
Core Material ◽  
Shell Material ◽  
Cycling Treatment ◽  
Energy Needs ◽  
Microencapsulated Phase Change Materials

Microencapsulated phase change materials (microPCMs) contain paraffin was fabricated by in-situ polymerization using methanol-modified melamine-formaldehyde (MMF) as shell material. The shell of microPCMs was sooth and compact with global shape, its thickness was not greatly affected by the core/shell ratio and emulsion stirring rate. More shell material in microPCMs could enhance the thermal stability and provide higher compact condition for core material. After a 100-times thermal cycling treatment, the microPCMs contain paraffin also nearly did not change the phase change behaviors of PCM. With the increasing of weight contents of microPCMs in gypsum board, the thermal conductivity (λ) values of composites had decreased. The simulation of temperature tests proved that the microPCMs/gypsum composite could store the time-dependent and intermittent solar energy, which did not necessarily meet the energy needs for space heating at all times.

Thermo-regulating properties of textiles with incorporated microencapsulated Phase Change Materials

MRS Advances ◽  
2020 ◽  
Vol 5 (18-19) ◽  
pp. 1023-1028
Author(s):  
Maria Cristina Larciprete ◽  
Stefano Paoloni ◽  
Gianmario Cesarini ◽  
Concita Sibilia ◽  
Vitalija Rubežienė ◽  
...  
Keyword(s):  
Phase Change ◽  
Phase Change Materials ◽  
Heat Energy ◽  
Infrared Emissivity ◽  
Scanning Calorimetry ◽  
Radiation Emission ◽  
Dynamic Tuning ◽  
Microencapsulated Phase Change Materials ◽  
Cotton Yarns ◽  
Fabric Surface

ABSTRACTPhase change materials (PCMs) are getting increasing interest due to their capacity to absorb, store and release heat energy. Their effectiveness is characterized by quantities of absorbed/released heat energy, expressed as enthalpy. Specifically, the larger is the enthalpy, the more efficient thermoregulation effect is achieved. With this in mind, PCMs can be used in the manufacture of thermally regulated clothing in order to minimize heat strain and simultaneously improve thermal comfort. Moreover, such materials also modify their infrared radiation emission during phase transition, thus they can be envisioned to exploit thermal shielding applications. The aim of the present research was to investigate the infrared emissivity of textiles composed by cotton yarns with dispersed PCMs. The organic microcapsules of phase change materials, having different binding to the fibre mechanisms, were padded onto the fabric surface by pad-dry-cure method. The thermal properties and stabilities were measured using differential scanning calorimetry, while infrared emissivity was characterized using infrared thermographic technique. The obtained experimental results show a dynamic tuning of IR emissivity during heating/cooling process which can be correlated to the type and properties (enthalpy of fusion) of the corresponding PCM.

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