Pet owners want to know what pet cooling mats are made of in the interests of the safety of their cats and dogs, I suspect. Firstly, pet cooling mats (pads), usually for dogs and cats, are made of a gel-like substance in a blue plastic cover. They cool cats and dogs or even humans when they rest on the mat. The mat does not require any electrical input. They cool the animal in a chemical process called “phase change”. The squishy gel inside the mat is a “phase change material (PCM)”.
PCM changes in structure causing cooling
Pet cooling pads are advertised as cooling devices which are activited under the pressure of the animal on the mat. However, this appears to be a little misleading because the cooling process takes place because the gel, as I understand it, changes in structure once disturbed. The process is not dependent in pressure per se. Although the pressure may alter the structure of the material causing it to cool. The substance remains a gel i.e. does not change from solid to liquid and vice versa, but invisible to the eye its fundamental structure changes. This change absorbs energy from the exterior. The absorption of energy from the exterior causes the cooling effect take place around the pad and on the pad.
Organic and inorganic PCMs
It’s quite a difficult concept to grasp, I find, but you can read about it on Wikipedia. The classic phase change material which causes cooling is ice melting to water. That is a solid changing into a liquid through the melting process (phase change). The cooling pads work on the same principles but there’s no actual melting and the material is not water. It is possibly either an organic PCM or an inorganic PCM. Organic PCMs are hydrocarbons, primarily paraffin’s and lipids but also one is sugar alcohol. Inorganic PCMs are salt hydrates.
I suspect that the gel inside the pet cooling pads are organic PCMs (but see below). It is not a material which changes from solid to liquid and then liquid to solid to the best of my knowledge. Wikipedia says that only phase changes between solid to liquid and liquid to solid are practical for PCMs. This undermines the concept of the pet cooling pad which appears to be a constant gel-like structure.
My preferred choice as to what the pads are made of other than the outer plastic cover
A further alternative is that the gel-like substance is sodium sulphate mixed with water or mixed with water and sodium chloride which according to a guy on the Internet, Jack Lopez, has “a phase change temperature [that] may be close enough for your dog cooling application”.
Hope this clarifies things a little. You need to be a specialist to fully understand this topic.
P.S. In an era of global warming these pads may become a boon to concerned cat and dog owners.
