Abstract: A process for the preparation of a random copolymer of at least one conjugated diene and at least one vinyl aromatic compound comprising reacting the monomers with the aid of an initiator based on lithium in the presence of an essentially inert solvent wherein said solvent consists of at least 60 per cent by weight of cyclopentane and the heat of reaction is withdrawn by means of reflux cooling.

Abstract: Composite polymers, especially composite polyols containing active hydrogen atoms can be prepared by polymerizing one or more olefinically unsaturated compounds in the presence of a liquid polymer containing active hydrogen atoms and a modified initiator; the modification comprising the reaction between a liquid polymer containing one or more groups which can react with isocyanato groups and a compound containing two or more isocyanato groups which has been partially converted by reacting it with an organic hydroperoxide or a free-radical initiator also containing additional active hydrogen atoms. The composite polymers exhibit a stable dispersed polymer phase and can be suitably applied as starting materials for polyurethane foams.

Abstract: Rubbery compositions having good cold-flow and processing characteristics comprise a particular blend of polymers or copolymers of conjugated dienes having 4 or 5 carbon atoms per molecule, or copolymers thereof with a monoalkenyl arene.