1, Features
SL-PCMs pure nature organic based phase change material
They are Organic compounds derived from animal fat and plant oils
They are renewable, they are bio-degraded
They are congruent melting thermodynamic
They are with minimal supercooling by comparison with Inorganic PCMs such as salt hydrates
Low Volumetric expansion from solid to liquid comparing with salt hydrates PCMs 10% volume change expansion
They have wide temperature range for option, can meet with various occasions and applications where the different relatively temperature desired
No phase segregation as the Inorganic PCMs which need to introduce agents to address the problem
They are non-corrosive, easy for various containments compatible with
2, Description
Phase change material(PCMs) typically can be divided into organic and inorganic by Materials. Our SL-PCMs is organic nature plan-based non paraffin-wax phase change material. Organic PCMs including the Paraffin and Bio-based.
As we discussed the water based PCMs like Ice,Ice Gel pack and dry Ice,due to they don’t have Carbon element in their chemical site, they can be concluded as Inorganic category, water also existing in another form- the crystalline salt hydrates, crystalline hydrated salt are the most typical application in the low-medium temperature of inorganic PCMs utilities,they have large amount of phase change heat fusion, and fixed temperature of melting point, actually it is the temperature desired to release the crystal water(before melting,crystal water bounded with inorganic salt),and the released water to dissolve the salt,which absorbs heat,and on the contrary, a reversible process occurs to capture crystal water and exothermic ciruit.
The crysalline hydrated salt PCMs have abilities as:
They are with high thermal conductivity
They are with great amount of dissolving heat
High density heat storage capacity
They basically in neutral
They are cheaper than organic PCMs
They have widely usage
However, the crystalline hydrated salt are vulnerable to supercooling and phase separation, ”supercooling” means that a substance does not crystallize when it condenses to the freezing point,which causing the problem of phase change temperature fluctuated.
Phase separation refer to the process of phase transition reversible,some inorganic salts are insoluble in the crystal water and collects at the bottom of container.and this phenomenon is irrevsersible,and it happens because of most of the crystalline hydrated salt melt incongruently,that is they melt to a saturated aqueous phase and solid phase which is generally a lower hydrate of same salt, as due to density difference,the salt phase settles out and problem phase separation occurs, this can be result in the crystalline salt hydrated completely lost the reversibility of phase transition.
Our SL-PCMS material referred as bio-based with congruent melting thermodynamic,will have no phase segregation problem,and have no supercooling phenomenon with oscillating temperature which resulting in lower effectiveness during transition and eventually lost their latent heat storage capacity and non-recyclable eventually.
3, Properties
Comparison Refer | TH-PCMs(Bio-based) | Crystalline Hydrated Salt(Inorganic) |
Latent Heat Capacity Range | 180-310 J/g | 86-328J/g |
Thermal Conductivity | 5W/m•K | 7.7W/m•K |
Melting point temperature range | 5-120°C | 15~80°C |
Fixed melting point | Yes | Yes |
Cost | Low | Ultra-low |
Flammability | Low | Low |
Supercooling | None | Most |
Phase segregation | None | Yes |
Toxic property | Non-toxic | Many |
Corrosive property | Non-corrosive | Many |
Volumetric Expansion in transition | Low | 10% |