The invention relates to an efficient process for the preparation and isolation of rubber particles formed in aqueous media having a tunable level of metal containing anti-agglomerants and rubber particles obtained thereby. The invention further relates to copolymer products comprising the same or derived therefrom.

A closed-cell foam water-stop sheet with an adhesion layer, wherein the closed-cell foam water-stop sheet comprises: the adhesion layer that comprises a rubber component (A) having a total content of 80% by mass or more of a butyl rubber (a1) and an ethylene-propylene-diene rubber (a2), and a petroleum resin-based tackifier (B), the adhesion layer having a thickness of 0.01 to 2.0 mm; and a closed-cell foam sheet having a closed cell ratio of 70% or more, the closed-cell foam sheet being integrally attached to the adhesion layer, and wherein a mass ratio of the ethylene-propylene-diene rubber (a2) to the butyl rubber (a1) [(a2)/(a1)] is 0/100 to 93/7, a content of the petroleum resin-based tackifier (B) is 0.5 to 20 parts by mass based on 100 parts by mass of the rubber component (A), and the closed-cell foam water-stop sheet with an adhesion layer has a 25% compression stress of 10 to 800 kPa.

The invention relates to an efficient process for the preparation and isolation of rubber particles formed in aqueous media and highly pure rubbers obtained thereby. The invention further relates to copolymer products comprising the same or derived therefrom.