Abstract: Purifying reagent for the purification of starting materials to be used in a metal compound catalyzed polymerization, containing proton donating reactive contaminants, consisting of a solid product, obtainable by the metallation of a product of a nucleophilic displacement reaction between a halogen alkylated crosslinked poly(vinylaromatic) resin and a metallated conjugated diene compound, which product is insoluble inorganic solvents, which is not able to initiate anionic polymerization of olefins or dienes and which is able to scavenge proton donating contaminants, which may hamper polymerizations catalysted by metal organic compounds; and process for purification of starting materials applying said purifying reagent.

Abstract: Purifying reagent for the purification of starting materials to be used in a metal compound catalyzed polymerization, containing proton donating reactive contaminants, consisting of a solid product, obtainable by the metallation of a product of a nucleophilic displacement reaction between a halogen alkylated crosslinked poly(vinlyaromatic) resin and a metallated conjugated diene compound, which product is insoluble inorganic solvents, which is not able to initiate anionic polymerization of olefins or dienes and which is able to scavenge proton donating contaminants, which may hamper polymerizations catalysted by metal organic compounds; and process for purification of starting materials applying said purifying reagent.

Abstract: A process for coagulation finishing (co)polymer by using polyvinyl alcohol as dispersant during said coagulation. In particular, low viscosity block copolymers, comprising at least one block of predominantly conjugated diene and at least one block of predominantly monovinyl aromatic monomer, can be successfully finished. The polyvinylalcohol is characterized by a weight average molecular weight of from 200 to 200,000 and by an average degree of hydrolysis of from 25 to 98%.