Polymers are chainlike macromolecules that are build-up from identical repetition units: the monomers. In the majority of cases they consist of a mixture of molecules that differ in their chain length. This property is often harmful as polymers nowadays fulfil more and more sophisticated tasks in medicine, cosmetics and technology. With our patented method, namely the "Continuous Spin Fractionation", we are able to remove unwanted components as well as low molecular weight impurities. On the following pages we inform you about the basics of molecular weight distributions of polymers, fractionation by means of liquid-liquid phase separation, and the working principle of the Continuous Spin Fractionation.