Abstract:
Manufacture of expandable styrene polymers which on expansion provide oval saddle-shaped discs suitable for use as bulk cushioning material. In the process, cylindrical extrudates of expandable styrene polymers are deformed at form 70* to 90*C by means of rollers to form strands of oval cross-section, which strands are then sliced to form discs by cutting in the direction of the short axis of said oval cross-section.
Abstract:
Solutions of N-vinylpyrrolidone polymers can be prepared with particular advantage by polymerization of N-vinylpyrrolidone in an aqueous medium by adding the polymerization catalyst in portions or continuously to the monomer solution in the form of a finely divided suspension in an aqueous solution of Nvinylpyrrolidone polymer.