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Pour point depressant (PPD)
Crude oil pour point depressant, lowers the freezing point of crude oil, improves the fluidity of crude oil, and achieves the purpose of wax prevention.

Crude oil loses fluidity because the waxes dissolved in the oil crystallize out as the temperature decreases. As the oil temperature drops, the solubility of the wax gradually decreases, and the wax crystals overlap and connect with each other to form a three-dimensional network structure, and the crude oil loses its fluidity.
The pour point depressant does not react chemically with crude oil, but changes the size and shape of the wax crystals, preventing the wax crystals from forming a three-dimensional network structure. However, the pour point depressant cannot inhibit the precipitation of wax crystals, but can only change the shape of the wax crystals, making the The ability of wax crystals to form a three-dimensional network structure is weakened, thereby enhancing the fluidity of crude oil.