Properties of layered structured PE/PP and PB-1/PP films having ultra-thin layers

Can the Structures of Semicrystalline Polymers be Controlled Using Interfacial Crystallographic Interactions?

“…The epitaxial crystallization of polymers provides a simple and efficient way to fabricate polymeric materials with special crystalline structures and thus improve properties or even generate new functionality, for example, the increased photoconductivity of the well aligned TA‐PPE 138. However, the use of these techniques to design and fabricate polymeric materials with properties matching specific product requirements has not been well developed, even though some positive effects of the resultant specific structures and morphologies on the mechanical and physical properties have been demonstrated 127–130, 138. Therefore, further research in this field is needed to explore how to utilize the induced unusual crystallization behavior of polymers for preparing advanced polymeric materials.…”

“…For non‐parallel alignment, as schematically depicted in Figure 9, the crosshatched lamellar structure leads to mechanically soft amorphous interlamellar regions of one phase being bridged by the crystalline lamellae of another phase, which leads to a significant improvement in the mechanical properties 127, 128. Also, the adhesion between polymer sheets with epitaxial crystallization can be enhanced remarkably.…”

Origin of Epitaxial Cold Crystallization of Poly(l-lactic acid) on Highly Oriented Polyethylene Substrate

“…This provides us a useful way to control the crystal structure and orientation of a wide variety of semicrystalline polymeric materials . The special orientation can cause synergistic effect on property modification. − Therefore, there are a vast body of literatures that describe the epitaxial crystallization of polymers on different substrates. Great progress in understanding the mechanism of polymer epitaxy at a molecular level has already been achieved. , It should be pointed out that most of the studies on polymer epitaxy focus mainly on the resultant mutual orientation relationship and its origin via atomic force microscopy, X-ray diffraction, and transmission electron microscopy combined with electron diffraction. , When the polymer chains start to orient on the ordered substrate was, however, not concerned so much up to date.…”

“…This leads to the formation of an unusual structure with the PLLA crystalline lamellae connecting the crystalline and amorphous phase of the PE, and vice versa. In this kind of configuration, excellent mechanical properties are expected for the blend under the consideration that the amorphous mechanical weak regions of one component are bridged by the crystalline lamellae of the other component. , Now the problem arises about when the PLLA chains start to align on the oriented PE film. In other words, we want to know whether there are already oriented PLLA chains in the amorphous solid before cold crystallization or not.…”

Preparation and Properties of PB-1/PP Blends

“…Robert et al [8] studied the characterization of fibers produced by melt spinning from blends of PB-1 and PP, and found that fibers showed mechanical properties that are in between the properties of the pure polymers. Jaballah et al [9] studied the mechanical properties, as well as thermal behavior and optical birefringence of PB-1=PP films having ultra-thin alternating layers of the two different polymers prepared by the solution-cast method.…”