Extrusion method, blending performances

Recently, Liu et al. [34] prepared banana fibre (BaF)-filled composites based on high-density polyethylene (HDPE)/polyaminde-6 (PA 6) blends via a two-step extrusion method. Maleic anhydride grafted styrene/ethylene-butylene/styrene triblock polymer (SEBS-g-MA) and maleic anhydride grafted polyethylene (PE-g-MA) were used to enhance impact performance and interfacial bonding between BaF and the resins. Mechanical, crystaUization/melting, thermal stability, water absorption and... 

One method is adding color via concentrates or a masterbatch at the fabrication step (molding or extrusion). The process involves a two-component approach a natural polymer and a concentrated (solid or liquid) additive masterbatch metered and blended at the press. In this option, the fabricator must take responsibility for preblending the product, properly mixing and dispersing the two phases, and performing checks and adjustments to assure final color quality. 

The ultrasonic treatment of PET/LCP blends leads to improvements in the mechanical properties of the homopolymers and some blends. The increase in the viscosity and mechanical properties of neat PET and LCP, as well as some of their blends at certain amplitudes, points toward homo- and copolymerization. The increase in viscosity of PET after ultrasonic treatment is attributed to possible esterification reaction. The presence of hairy structures on the surface of LCP droplets in the core region of 90/10 PET/LCP blends after ultrasonic treatment at an amplitude of 7.5 otm illustrates the improved adhesion between the PET and LCP phases, and possible copolymer formation under the action of ultrasound. Low residence times in the ultrasonic zone and energy saving due to reduced pressure render ultrasonic extrusion a viable method for the compatibilization of thermoplastic polymer/thermotropic LCP blends. Further refinement of processing conditions could allow one to achieve greater enhancements in the performance of LCP, and its blends with PET. 

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