With its unique combination of properties propylene glycol supports many uses.
The propylene glycol molecule is chemically neutral, i.e. it usually does not react with other substances. This is a particularly helpful property in the combining of contrasting chemicals, for example in a perfume, to create a single, homogeneous fluid.
By emulsifying active ingredients, which otherwise would not mix, propylene glycol helps to create a stable homogeneous fluid allowing for the intended final product, such as a face cream or shampoo to perform its function.