Optical scattering monitor

A monitoring system, useful for illuminating and acquiring scattered light intensity data from a flowing polymer solution, the monitoring system comprising:

• a vessel for processing said polymer solution;
• a monitoring cell comprising a laser, a photodetector, and a flow tube, wherein said laser is capable of producing a beam of hg t that is scattered by said polymer solution, wherein said flow tube is capable of allowing said polymer solution to flow therethrough, and wherein said photodetector is positioned to receive light passed through and scattered by said polymer solution in said flow tube and is capable of measuring the intensity of said scattered light;
• a feed path and a return path both connecting the monitoring cell to the vessel, said flow tube being connected between said feed path and said return path;
• and
• a pump connected in the feed or return path and capable of effecting flow of said polymer solution from said vessel to said monitoring cell, said pump configured to run continuously during said light intensity measurement;
• wherein said vessel, said feed path, said pump, and said monitoring cell are configured such that the solvent:polymer ratio of said polymer solution remains substantially the same as said polymer solution flows from said vessel to said monitoring cell.