Composite nanofibrillar polymer

Fakirov S (2009) Toward nanofibrillar single polymer composites, eXPRESS Polym Lett 3 200. 

Fakirov S (2009) Towards nanofibrillar single poljnner composites. Express Polym Lett 3 200. Bhattacharjfya D, Maitrot P and Fakirov S (2008) Polyamide 6 single poljoner composites. Express Polym Lett 3 525-532. 

Fig. 6.6 SEM micrographs of nanofibrillar polymer-polymer composite based on LLDPE/PVDF and their reinforcing component a cryofractured surface of a NFC made parallel to the draw direction, b neat PVDF nanofibrils after removing of LLDPE from the drawn LLDPE/PVDF blend...

Panamoottil SM, Bhattacharyya D, Fakirov S (2013) Nanofibrillar polymer-polymer and single polymer composite involving poly(butylene terephthalate) preparation and mechanical properties. Polym Plast Technol Eng 52(11) 1106-1112... 

Another illustrative example of nanofibrillar SPCs is that of PVDF [81], shown in Fig. 12.5, where the PVDF nanofibrils were isolated from the nanofibrillar polymer-polymer composites but not from the drawn blend directiy as in the previous case (Fig. 12.4). Basically, again the same above described protocol for isolation of neat nanofibrils was followed. 

Fig. 12.5 SEM micrographs of the various stages of pieparation of nanofibrillar SPCs a ciyo actured surface made parallel to the draw direction of nanofibrillar polymer-polymer composite based on LLDPE/PVDF highly drawn blend subjected to compression molding, b neat PVDF nanofibrils after extraction with selective solvent of IXDPE from the IXDPEfPVDF polymer-polymer composite (a), c cryofractured cross section of nanofibrillar single polymer composite prepared via compression molding of the parallel aligned neat PVDF nanofibrils (b), d surface of the nanofibrillar SPC shown in (c) demonstrating the adherence of PVDF nanofibrils due to surface premelting only...

Before discussing the mechanical properties of the true nanofibrillar SPCs let remind those of the nanofibrillar polymer-polymer composites prepared according to the MFC concept [33, 60-69]. In Table 12.2 are summarized the improvements in tensile modulus, E, and tensile strength, a, of three different nanofibrillar polymer-polymer composites as compared with isotropic matrix material (PP and LLDPE), as well as with PP/glass fibers (GF) composite. The improvements of tensile modulus are between 50 and 150 % and for the tensile strength— between 20 and 230 % (Table 12.2). 

The superior mechanical performance of the nanofibrillar polymer-polymer composites, prepared according to the concept of converting instead of adding [15] (Table 12.2) originates from the very high aspect ratio of nanofibiils, their better adhesion then the mineral fillers to the matrix and mostly from the perfect... 

Table 12.2 Improvements of tensile modulus, E, and tensile strength, a, of nanofibrillar polymer-polymer composites...

New polymer nanocomposites which seem to be particularly promising for structmal apphcations as a result of their exceptional mechanical properties, are nanofibrillar single-polymer composites (SPCs). These novel materials are reinforced with polymer nanofibrils with diameters in the range of 50-150 nanometers [31]. 

Finally, in order to take full advantage of the exceptional mechanical properties reported for nanofibrillar single-polymer composites, their processing method should be optimized. 

Mechanical Properties of PLA/PGA Nano-/Microfibrillar Polymer-Polymer Nanofibrillar Composites... 

The micro- and nanofibrils isolated in a neat form after selective dissolution of the second blend component, even after preparation of fabrics or knitted articles from the blend yarn, can be used as a starting material for preparation of nanostructured single polymer composites. A PET nanofibrillar SPC prepared via hot compaction using one constituent shows a modulus competitive with that of the glass fiber/PE (40/60 by wt) composites. 

Fakirov S, Duhovic M, Maitrot P and Bhattacharyya D (2010) From PET nanofibrils to nanofibrillar single-polymer composites, Macromol Mater Eng 205 515-518. 

Fakirov S and Bhattacharyya D (2005) Nanofibrillar-, microfibrillar- and microplates reinforced composites - new advanced materials from polymer blends for technical, commodity and medical applications, Proc 2H Ann Meet Polym Proc Soc (PPS 21), June 19-23, Leipzig, Germany. 

Polymer-polymer composites or self-reinforced polymeric materials (SRPM) are materials where both the reinforcement and matrix components have been made from all polymeric materials. This can include two polymers coming from the same family of polymers or simply the same polymer. Micro- and nanofibrillar single polymer composites (SPCs) are a subcategory of self-reinforced polymeric materials which are made by combining the properties of molecularly aligned and oriented forms with randomly disoriented forms of the same polymer material. It can be debated whether or not such a material can still be called a composite as it is not made of two or more dissimilar materials. However, one thing is for sure, the two forms of the material can exhibit very different mechanical properties. 

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