Smart blending technology enabled by chaotic advection

Abstract

ABSTRACT:Polymer blending has been typically regarded as a mixing process rather than a structuring process so polymer blends and composites are not necessarily optimized with regard to structure, properties, and composition. In this article, a new smart blending technology is described whereby melt components and solid additives are more controllably organized into micrometer-scale and sub-micrometer-scale shapes and arrangements to improve properties or impart functionality to extruded plastics. Chaotic advection is an enabling recent subfield of fluid mechanics for smart blending. It provides a method to controllably stretch and fold melt domains and evolve a multilayered structure leading to derivative morphologies, or indirectly manipulate solid additives. Recent advances in fluid mechanics have thereby been implemented to reconsider how blending is done. A variety of structured plastic materials are producible with a single smart blending device with no device alterations. Several examples and their improved physical properties are shown or discussed.

Tailored Additive Release Rates in Extruded Plastic Films Produced With Smart Blending Machines

“…Despite such complicating considerations, results with smart blenders are repeatable and their on-line control features ( Figure 2) can be used to determine systematically how particular blend morphologies influence physical properties of interest. Due to low shear rates, viscosity ratio C m (i.e., the ratio of the minor component shear viscosity to the major component shear viscosity) and interfacial tension are primary melt parameters that affect progressive morphology development in smart blenders [21]. Desirable values are C m % 1 and low interfacial tension (55 mN/m).…”

Progresses in Food Packaging, Food Quality, and Safety—Controlled-Release Antioxidant and/or Antimicrobial Packaging

“…The processing method strongly influences the release rates of CRP, which is why CRP films can be produced by traditional processing methods (cast film extrusion, blown film extrusion, and solvent casting, which is the use a smart blender attached to one or more extruders to produce polymer blend films with very different morphologies from those obtained by conventional extrusion methods) [ 217 ]. At the same time, special polymer blend morphologies of the LDPE/PP or LDPE/HDPE blends, from which ACs (as tocopherol) are released with desirable rates [ 218 , 219 ], were obtained by using a smart blending by manipulating polymer compositions and film morphologies.…”

Effects of periodic and non‐periodic chaotic mixing on morphology development of immiscible polymer blends

“…Fundamental studies on the mechanism of chaotic mixing have been conducted in nonlinear dynamic theory from a theoretical point of view since the pioneering work of Aref14 and Ottino 15. Zumbrunnen and coworkers22–26 were the first to study the blending of polymers by chaotic mixing. They used two designs of batch chaotic mixing devices such as a journal bearing24 and an eccentric disk chaotic mixer (EDCM)23 to investigate the morphology development in polymer blends at various compositions.…”

“…with a variety of morphologies in continuous lengths. The process, called as smart blending,25,27 can offer unprecedented control of internal structure development. Jana and coworkers,7,28,29 designed a 2D batch chaotic mixer, and investigated the effects of chaotic mixer geometry, operating parameter, mixing waveforms, viscosity ratio, and composition of polymer blends on the development of morphology.…”