Preparation of High Security N-Octadecane MicroPCMs by In Situ Polymerization

2015 ◽  
Vol 727-728 ◽  
pp. 141-144
Author(s):  
Xiao Qiu Song ◽  
Yu Ping Duan ◽  
Yue Xia Li
Keyword(s):  
Phase Change ◽  
Phase Change Materials ◽  
Urea Formaldehyde ◽  
Functional Materials ◽  
Formaldehyde Resin ◽  
Melamine Formaldehyde ◽  
Formaldehyde Content ◽  
Synthesis Conditions ◽  
Polymerization Method

N-octadecane microcapsules phase change materials(MicroPCMs) were prepared by thein-situ polymerization method using n-octadecane as core materials, urea-formaldehyde resin as shellmaterials respectively. Melamine–formaldehyde (MF) microcapsules have been widely applied inmany functional materials. Free formaldehyde content are important safetyfactor determining the survival of the microcapsules during fabrication andapplication. In this study, the formaldehyde content of n-octadecane MicroPCMs decrease to 0.35g/Kg which even lower than the standard EuropeanE3 level (0.6g/Kg) through regulation the synthesis conditions such as urea/formaldehyderatio of weight from 1:2 to 1:1.6, urea batch feeding three times ,curing endpH value to 1.0-1.5,reactive time extend to 4h,addition melamine and PVA.

Preparation and Characterization of Hexadecane Microcapsule Phase Change Materials by In Situ Polymerization

2013 ◽  
Vol 815 ◽  
pp. 367-370 ◽  
Author(s):  
Xiao Qiu Song ◽  
Yue Xia Li ◽  
Jing Wen Wang
Keyword(s):  
Particle Size ◽  
Phase Change ◽  
Phase Change Materials ◽  
In Situ Polymerization ◽  
Urea Formaldehyde ◽  
Agitation Speed ◽  
Urea Formaldehyde Resin ◽  
Formaldehyde Resin ◽  
Mass Ratio

Hexadecane microcapsule phase change materials were prepared by the in-situ polymerization method using hexadecane as core materials, urea-formaldehyde resin and urea-formaldehyde resin modified with melamine as shell materials respectively. Effect of melamine on the properties of microcapsules was studied by FTIR, biomicroscopy (UBM), TGA and HPLC. The influences of system concentration, agitation speed and mass ratio of wall to core were also investigated. The results indicated that hexadecane was successfully coated by the two types of shell materials. The addition of melamine into the urea-formaldehyde resin microcapsule reduced microcapsule particle size and microencapsulation efficiency. The influences of factors such as system concentration, agitation speed and mass ratio of wall to core to different wall materials microcapsules presented different variety trends of the microcapsule particle size.

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.

Synthesis and Properties of Melamine-Formaldehyde/Montmorillonite Nanocomposites

2008 ◽  
Vol 8 (4) ◽  
pp. 1775-1781 ◽  
Author(s):  
Haitao Wang ◽  
Xiangfu Meng ◽  
Zhongzhong Qian ◽  
Hu Zhou ◽  
Yanfen Ding ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Raman Spectroscopy ◽  
Chemical Resistance ◽  
Formaldehyde Resin ◽  
Polycondensation Reaction ◽  
Melamine Formaldehyde ◽  
Formaldehyde Content ◽  
Acetyl Acetone ◽  
Modified Montmorillonite

In this paper, intercalated and partially exfoliated melamine-formaldehyde (MF)/montmorillonite (MMT) nanocomposites have been synthesized successfully via in-situ polymerization based on pristine montmorillonite, acidified montmorillonite and organic modified montmorillonite respectively. The obtained nanocomposites were characterized by XRD, TEM, TGA, and Raman spectroscopy. Free formaldehyde content of those composites was also determined by acetyl acetone technique. It was found that acidified montmorillonite and organic modified montmorillonite could catalyze the polycondensation reaction of methylolmelamines. The thermal stability and chemical resistance of those two nanocomposites were also improved dramatically compared to pure melamine-formaldehyde resin.

scholarly journals Experimental Study of Using Micro-Encapsulated Phase-Change Material Integrated into Hemp Shive Wallboard

Buildings ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 228
Author(s):  
Edgars Kirilovs ◽  
Inga Zotova ◽  
Staņislavs Gendelis ◽  
Hans Jörg-Gusovius ◽  
Silvija Kukle ◽  
...  
Keyword(s):  
Heat Capacity ◽  
Phase Change ◽  
Phase Change Materials ◽  
New Technologies ◽  
Urea Formaldehyde ◽  
Single Layer ◽  
Mass Effect ◽  
Automatic Regulation ◽  
Formaldehyde Resin ◽  
Thermal Mass

Phase change materials (PCMs) are now widely known as potential additives for building insulation materials to provide a thermal mass effect that helps conserve energy and maintain a comfortable indoor temperature. Therefore, the study presented in this paper focuses on an experimental investigation of the specific heat capacity and thermal conductivity of hemp shive mixed with PCMs. Industrially manufactured organic PCM-S50 received from MikroCaps Ltd. (Slovenia) has been used to further enhance respective properties of the product samples. The experimental boards were made from hemp shive by directly mixing 5% encapsulate PCMs into the mass. Cold pressing was used to manufacture the boards with Kleiberit urea formaldehyde resin glue as a binding agent. The experimental boards were made as 25 mm thick single-layer parts with a density of 300 ± 20 kg/m3, which qualify them as low-density boards. By adding nanocapsules during the board manufacturing process, the heat capacity is increased by 62%. Based on the great potential of using latent heat, it becomes a possible solution for the development of new technologies related to the automatic regulation of an indoor microclimate.

The Research of the Phase Change Materials Enclosed by β-CD

2011 ◽  
Vol 374-377 ◽  
pp. 352-356
Author(s):  
Sheng Jun Fu ◽  
Bo Liu ◽  
Wu Biao Duan ◽  
Jin Chang
Keyword(s):  
Phase Change ◽  
Phase Change Materials ◽  
Urea Formaldehyde ◽  
Urea Formaldehyde Resin ◽  
Formaldehyde Resin ◽  
Related Research ◽  
Enclosure Method ◽  
The Common ◽  
Wall Materials

This paper demonstrates that β-CD which encloses industrialized paraffin, one of the phase change materials, is utilized to prevent the leak of the paraffin. The enthalpy of the phase change materials which are enclosed is studied by characterizing of DSC. The result shows that the enthalpy of paraffin which has been enclosed by β-CD is increased by 29%. The related research contents had not been reported in literature. This method, compared with the common encapsulation of paraffin by wall materials, like the urea formaldehyde resin, not only is a new exploration on the enclosure method and the increasing of the enthalpy of the phase change materials, but also meets the requirement of enviromental protection.

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