NOVEL STRUCTURES BY MICROLAYER COEXTRUSION - TALC-FILLED PP, PC SAN, AND HDPE/LLDPE/

Numerous examples in the literature illustrate how the coextrusion of film with three or more polymeric layers is economically used to achie ve a desirable mix of end-use characteristics. More recently, layer-mu ltiplying devices permit two polymers of widely dissimilar solid-state properties to be combined into unique microlayer and nanolayer struct ures with hundreds or thousands of alternating layers. If the layers a re thin enough, the key properties of the constituents can combine syn ergistically. The microlayer structure is also an effective research t ool. Because the microlayer and nanolayer structures contain large spe cific interfacial areas. they are ideal for fundamental studies of phe nomena such as interdiffusion and adhesion. Three examples of microlay ered materials with up to 1024 layers illustrate the versatility of th is coextrusion process: talc-filled PP, PC/SAN, and HDPE/LLDPE.