It is used to cool products such as ice packs, refrigerants and cooling agents , the main principle is that using the reaction of ingredients to make endothermic process, so as to achieve the cooling effect.
The main components of making ice pack: sodium nitrate, sodium borate, sodium carboxymethyl cellulose, sodium silicate, sodium chloride and sodium hydroxide. The general preparation method is the proportion of the above formula according to the ratio, weigh sodium carboxymethyl cellulose and add sodium borate, stirring and heating until the solution becomes transparent and then stop heating, to obtain a solution 1; while stirring add sodium nitrate to the solution 1, sodium sulfate decahydrate and sodium silicate, then stir to obtain a solution 2; sodium hydroxide is added to the solution, stir, then add sodium chloride, stir until the solution is transparent, into the bag, you get finished ice packs. Chemical ice pack with refrigeration temperature is low, the advantages of long cooling time.
The so-called cold storage or cooling agent, mainly consists of the antifreeze, thickener and water , including ethylene glycol of antifreeze; thickeners, including sodium carboxymethyl cellulose and sodium alginate. The step of preparing the coolant is very simple. First, the thickener such as sodium carboxymethylcellulose is completely dissolved in water to form a gel solution with good transparency. After the solution is stabilized, an antifreezer such as ethylene glycol is added while stirring, Stir well, you can get cooling agent. Such cooling agent can be widely used in ice packs to improve the service life and provide better cooling effect.