Thermo-optical reaction changes of a PCM filled glass system

Abstract This paper analyzes thermo-optical reactions of the PCM-based glass element which has the capability to store thermal energy together with a variable transparency level through the energy storage process corresponding to phase change. Optical properties are determined by the level of phase transition at given boundary conditions over time. Special uncommon thermo-optical changes occur during its internal phase transition processes, from liquid to solid phase and vice versa (latent heat of fusion) within a given narrow range of temperature interval. PCM acts as random and diffusive media with relevant scattering effects in solid phase, however in liquid state are highly transparent with direct transmission and no relevant scattering effect. These internal physical changes were detailly identified by experimental test procedures based on optical properties measurements performed using a spectrophotometry, and parallelly with the stabilization of each temperature set provided by environmental chamber. As result of that, relevant differences in the PCM spectral feature can be identified for its different states (solid/liquid) in which transmittance spectra are unstable during rapid phase change process. This provides a substantial base line for the optimization of a PCM glazing system in terms of various degree of freedom for different building types and climate zones.

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Preparation and properties of shape-stabilized phase change material cellulose benzoate-g-polyoxyethylene (2) hexadecyl ether with potential for thermal energy storage

Textile Research Journal ◽

10.1177/0040517518773379 ◽

2018 ◽

Vol 89 (8) ◽

pp. 1512-1521

Author(s):

Na Han ◽

Wenxin Zhang ◽

Xiufang Wang ◽

Xingxiang Zhang ◽

Wei Li ◽

...

Keyword(s):

Phase Transition ◽

Energy Storage ◽

Phase Change ◽

Thermal Energy ◽

Thermal Energy Storage ◽

Solid Phase ◽

Resonance Spectroscopy ◽

Thermal Reliability ◽

Scanning Calorimetry ◽

Chemical Structures

It is a worldwide challenge to efficiently use renewable resources to solve the current energy shortage. The existing cellulose-based material is incapable of proper power storage. In this study, a series of cellulose benzoate-g-polyoxyethylene (2) hexadecyl ether (CB-g-E2C16) solid–solid phase change materials were synthesized with cellulose as the skeleton and polyoxyethylene (2) hexadecyl ether (E2C16) as a functional side chain. The skeleton cellulose and benzoyl chloride restrict the free movement of the molecular chains of E2C16 above the phase transition temperature, leading to a solid–solid phase change. Fourier transform infrared spectroscopy and nuclear magnetic resonance spectroscopy were performed to investigate the chemical structures. The thermal energy-storage properties, thermal reliability and thermal stability of the CB-g-E2C16 were investigated by differential scanning calorimetry and thermogravimetry (TG) methods. The analysis results indicated that the E2C16 chains were successfully grafted onto the cellulose benzoate (CB) backbone and the copolymers exhibited typical solid–solid phase transition behavior. The enthalpy and degree of substitution of graft copolymers CB-g-E2C16 could be adjusted by changing the feeding ratio of the raw materials, reaction temperature and post-processing methods of CB. TG analysis results showed that the CB-g-E2C16 copolymers possessed good thermostability and they keep their stability up to 278℃. Compared with pure cellulose, CB-g-E2C16 copolymers could be dissolved in dimethyl sulfoxide and most of them could be dissolved in N, N-dimethylformamide.

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Preparation and Characterization of a Novel Polyurethane Solid-Solid Phase Change Materials

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.785-786.613 ◽

2013 ◽

Vol 785-786 ◽

pp. 613-617

Author(s):

Gui Fang Wang ◽

Dong Ying Li ◽

Guang Ling Pei

Keyword(s):

Phase Transition ◽

Polyethylene Glycol ◽

Phase Change ◽

Phase Change Materials ◽

Solid Phase ◽

Soft Segment ◽

Condensation Reaction ◽

Diphenylmethane Diisocyanate ◽

Scanning Calorimetry ◽

Polarization Optical Microscopy

A novel solid-solid phase change materials was synthesized by the two-step condensation reaction of polyethylene glycol (PEG1000), neopentyl glycol (NPG) and 4, 4-diphenylmethane diisocyanate (MDI). Polyethylene glycol (PEG1000) was used as soft segment and 4, 4-diphenylmethane diisocyanate (MDI) as hard segment. The composition, structure and phase change properties were characterized by Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), thermogravimetric analyzer (TGA), polarization optical microscopy (POM) respectively. The results indicated that the PCM appeared typical solid-solid phase transition property and the phase change enthalpy and phase transition temperature reached to 120.45 J/g and 37.32°C, respectively.

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Effects of Al2O3, CuO and TiO2 nanoparticles son thermal, phase transition and crystallization properties of solid-solid phase change material,

Mechanics of Materials ◽

10.1016/j.mechmat.2018.10.004 ◽

2019 ◽

Vol 128 ◽

pp. 64-88 ◽

Cited By ~ 12

Author(s):

K P Venkitaraj ◽

S Suresh

Keyword(s):

Phase Transition ◽

Phase Change ◽

Tio2 Nanoparticles ◽

Phase Change Material ◽

Solid Phase ◽

Crystallization Properties ◽

Thermal Phase Transition ◽

Thermal Phase ◽

Change Material

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Pressure Effects on the Optical Properties of NdVO4

Crystals ◽

10.3390/cryst9050237 ◽

2019 ◽

Vol 9 (5) ◽

pp. 237 ◽

Cited By ~ 8

Author(s):

Enrico Bandiello ◽

Josu Sánchez-Martín ◽

Daniel Errandonea ◽

Marco Bettinelli

Keyword(s):

Phase Transition ◽

Optical Properties ◽

Absorption Band ◽

Phase Change ◽

Band Gap ◽

Pressure Dependence ◽

Structural Changes ◽

Pressure Effects ◽

Absorption Bands ◽

Fundamental Absorption Band

We report on optical spectroscopic measurements in pure NdVO4 crystals at pressures up to 12 GPa. The influence of pressure on the fundamental absorption band gap and Nd3+ absorption bands has been correlated with structural changes in the crystal. The experiments indicate that a phase transition takes place between 4.7 and 5.4 GPa. We have also determined the pressure dependence of the band-gap and discussed the behavior of the Nd3+ absorption lines under compression. Important changes in the optical properties of NdVO4 occur at the phase transition, which, according to Raman measurements, corresponds to a zircon to monazite phase change. In particular, in these conditions a collapse of the band gap occurs, changing the color of the crystal. The changes are not reversible. The results are analyzed in comparison with those deriving from previous studies on NdVO4 and related vanadates.

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Rapid phase transition of a phase-change metamaterial perfect absorber

Optical Materials Express ◽

10.1364/ome.3.001101 ◽

2013 ◽

Vol 3 (8) ◽

pp. 1101 ◽

Cited By ~ 67

Author(s):

Tun Cao ◽

Chenwei Wei ◽

Robert E. Simpson ◽

Lei Zhang ◽

Martin J. Cryan

Keyword(s):

Phase Transition ◽

Phase Change ◽

Perfect Absorber ◽

Rapid Phase ◽

Rapid Phase Transition ◽

Metamaterial Perfect Absorber

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CONTROL OF HEAT RELEASE ENERGY DURING HEATING FROM SOLID-SOLID PHASE CHANGE MATERIAL

10.1615/ihtc16.ecs.024007 ◽

2018 ◽

Author(s):

Ryohei Gotoh ◽

Tsuyoshi Totani ◽

Masashi Wakita ◽

Harunori Nagata

Keyword(s):

Phase Change ◽

Heat Release ◽

Phase Change Material ◽

Solid Phase ◽

Change Material

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Temperature Effect on the Two-Dimensional Phase Transition Kinetics of Adenine Adsorbed at the Hg Electrode/Aqueous Solution Interface

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc20031407 ◽

2003 ◽

Vol 68 (8) ◽

pp. 1407-1419 ◽

Cited By ~ 3

Author(s):

Claudio Fontanesi ◽

Roberto Andreoli ◽

Luca Benedetti ◽

Roberto Giovanardi ◽

Paolo Ferrarini

Keyword(s):

Phase Transition ◽

Aqueous Solution ◽

Phase Change ◽

Temperature Effect ◽

Transition Rate ◽

Effect Of Temperature ◽

Two Dimensional ◽

Solution Interface ◽

Phase Transition Kinetics ◽

Kinetics Of

The kinetics of the liquid-like → solid-like 2D phase transition of adenine adsorbed at the Hg/aqueous solution interface is studied. Attention is focused on the effect of temperature on the rate of phase change; an increase in temperature is found to cause a decrease of transition rate.

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