Tbe effect of mixing procedures on compatibilized nylon-6/PPO blends

The effect of three mixing procedures on compatibilized nylon-6/PPO blends was investigated. A twin-screw extruder was used in the experiment. (A) The mixture of nylon-6, PPO and TPEg was extruded; (B) the preblends of nylon-6 and TPEg through the extruder was co-extruded with PPO; (C). the preblends of PPO and TPEg through the extruder was co-extruded with nylon-6. The experimental results showed that the rational adaptation of processing method greatly affected the phase structure of the blend, and consequently affected the final properties of materials, such as mechanical properties, thermal properties and dimensional stability. The impact strength of the compatibilized nylon-6/PPO blends prepared via mixing procedure (C) is much higher than that of the compatibilized nylon-6/PPO blends prepared via mixing procedure (A) and (B) The reason is that the reactivity of -OH groups on PPO molecules is much lower than that of -NH2 groups on nylon molecules. In mixing procedure (C), PPO was first preblended with TPEg which allowed the -OH group to react with part of the maleic anhydride groups, then in the following co-extrusion with nylon-6 the un-reacted maleic anhydride groups further reacted with -NH2 groups on nylon molecules. With the two steps a good interface is formed and greatly improves the impact strength of the blends, and the material has the property of super toughness.