Influence of compatibilizer on the breakup of polymeric threads

Influence of a compatibilizer on the breakup of polymeric threads in an immiscible polymeric system consisting of Polyamide 6 and Polystyrene was studied via breaking thread method (BTM). Styrene-b-Ethylene-Butylene-b-Styrene copolymer grafted with maleic anhydride (SEBS-g-MA) was used as compatibilizer which was either incorporated in the bulk of PA6, or localized at the interface of two polymers. For both types of samples the breakup of PA6 threads was studied as a function of compatibilizer concentration. It was found that addition of compatibilizer to the bulk of PA6 retards final breakup. Such effect was more important when compatibilizer was localized at the interface of two fluids. Moreover, it was found that the sample preparation method is a determining factor on the mechanism of thread breakup since a beads-on-a-string (BOAS) morphology was observed in the latter case. This result was explained by Marangoni effect and viscoelasticity imparted to the interface by compatibilizer