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Thisstudy aims to develop a concept of reactive compatibilizer-tracer,which allows one to study the evolution of the morphology and interfacialreaction of reactive polymer blends in a large-scale twin-screw extruder(TSE). A reactive compatibilizer-tracer is a compatibilizer precursorwhose polymer chain bears reactive groups capable of reacting withat least one of the polymer components of a polymer blend. It alsobears moieties capable of being analytically detected with great accuracy.This concept is shown for polystyrene (PS)/polyamide 6 (PA6) blendsusing a copolymer of styrene (St), 3-isopropenyl-α,α′-dimethylbenzeneisocyanate (TMI), and 9-(methylaminomethyl)anthracene (MAMA) as areactive compatibilizer-tracer (PS-TMI-MAMA). While its isocyanategroups are capable of reacting with the terminal group of the PA6forming a graft copolymer of PS-g-PA6-MAMA, its anthracenemoieties allow for measuring very small amounts of the reacted reactivecompatibilizer-tracer or in situ formed graft copolymer by gel permeationchromatography (GPC) with an ultraviolet (UV) detector. The use ofthe reactive compatibilizer-tracer together with transit experimentsprovides a tool for studying reactive blending processes in a twin-screwextruder. [ABSTRACT FROM AUTHOR]

Thiswork aims to probe the roles of ethylene–propylenesegmented copolymer (EPS) in impact polypropylene copolymers (IPCs)by rheological and morphological investigations. A series of IPCswith different EPS contents and molecular structures are preparedby an atmosphere-switching polymerization process (ASPP). The Palierneemulsion model is used to describe the relationship between the rheologicalresponse to small amplitude oscillatory deformation and the morphologyof IPC. It is found that this model describes well the linear viscoelasticresponses of IPC, if the role of EPS is taken into account. An increasein the content of EPS and the length of its PP segments leads to adecrease in the size of the ethylene–propylene random copolymer(EPR) phase domains and the interfacial tension. These results stronglyconfirm the role of the EPS as a compatibilizer in the IPC system.The adhesion between the PP matrix and the EPR phase domains is enhancedby the presence of the EPS that is produced in situ during the ASPP.For this reason, ASPP is capable of making IPC with an excellent rigidity–toughnessbalance. [ABSTRACT FROM AUTHOR]