COMPOUNDING. Bimodal polyolefins pose a new challenge to compounding lines, as long and short chain components with widely different viscosities must be homogenised to produce a uniform pellet stock, free of fish eyes. The novel ZSK-NT system opens up new routes to this difficult compounding task. First melting is carried out in a specially designed twin-screw kneader, and the melt is then transferred to a second twin-screw kneader specially optimised for homogenisation.