Blends, composites and multiphase polymeric materials

Definitions of terms related to polymer blends, composites, and multiphase polymeric materials (lUPAC Recommendations 2004), Pure Appl. Chem. 76, 1985-2007 (2004). Reprinted as Chapter 9, this edition. 

Definitions of terms related to polymer blends, composites, and multiphase polymeric materials... 

Definitions of Terms Related to Polymer Blends, Composites, and Multiphase Polymeric Materials (2004), 186... 

Work WJ, Hess KHM et al (2004) Definitions of terms related to polymer blends, composites, and multiphase polymeric materials. Pure Appl Chem 76(11) 1985-2007 Wanapun D, Kestur US et al (2010) Selective detection and quantitation of organic molecule crystallization by second harmonic generation microscopy. Anal Chem 82 5425-5432 Wanapun D, Kestur US et al (2011) Single particle nonlinear optical imaging of trace crystallinity in an organic powder. Anal Chem 83 4745-4751... 

Definition of terms related to polymer blends, composites, and multiphase polymeric materials This recommendation defines the most commonly used terms encountered when dealing with polymer blends and composites and is limited to mixtures in which the components differ in chemical composition or molar mass or both and in which the polymer forms the continuous phase. Many of the multiphase systems are in fact biphasic systems with a multitude of finely dispersed phase domains. Crystalline and liquid crystalline multiphase systems are the subject of other documents. 

A detailed listing of the definitions of the many terms employed in polymer blends, composites and multiphase polymeric materials (lUPAC recommendation 2004) is provided in [53]. 

Work, W.J., Horie, K., Hess, M., Stepto, R.F.T., 2007. Definitions of Terms Related to Polymer Blends, Composites, and Multiphase Polymeric Materials, 76, pp. 1985-2007. 

The study of electroconductive polymer systems, based on conductive particles and polymer blends, has been quite intensive during the recent past. Gubbels et al. [149] studied the selective localization of CB particles in multiphase polymeric materials (PS and PE). According to these results, the percolation threshold may be reduced by the selective localization of CB. The minimum resistivity was obtained when double percolation (phase and particle percolation) exists in the PS-PE blend. In addition, it was found that the percolation threshold may be obtained at very low particle concentrations, provided that CB is selectively localized at the interface of the blend components. Soares et al. [150] found that the type of CB (i.e., different surface areas) does not affect the conductivity of the blend with 45/55 PS/PIP (polyisoprene) composition. 

The properties of block copolymers, on the other hand, cannot be calculated without additional information concerning the block sizes, and whether or not the different blocks aggregate into domains. The results of calculations using the methods developed in this book can be inserted as input parameters into models for the thermoelastic and transport properties of multiphase polymeric systems such as blends and block copolymers of immiscible polymers, semicrystalline polymers, and polymers containing various types of fillers. A review of the morphologies and properties of multiphase materials, and of some composite models which we have found to be useful in such applications, will be postponed to Chapter 19 and Chapter 20, where the most likely future directions for research on such materials will also be pointed out. 

Scanning electron microscopy (SEM) is one of the very useful microscopic methods for the morphological and structural analysis of materials. Larena et al. classified nanopolymers into three groups (1) self-assembled nanostructures (lamellar, lamellar-within-spherical, lamellar-within-cylinder, lamellar-within-lamellar, cylinder within-lamellar, spherical-within-lamellar, and colloidal particles with block copolymers), (2) non-self-assembled nanostructures (dendrimers, hyperbranched polymers, polymer brushes, nanofibers, nanotubes, nanoparticles, nanospheres, nanocapsules, porous materials, and nano-objects), and (3) number of nanoscale dimensions [uD 1 nD (thin films), 2 nD (nanofibers, nanotubes, nanostructures on polymeric surfaces), and 3 nD (nanospheres, nanocapsules, dendrimers, hyperbranched polymers, self-assembled structures, porous materials, nano-objects)] [153]. Most of the polymer blends are immiscible, thermodynamically incompatible, and exhibit multiphase structures depending on the composition and viscosity ratio. They have two types of phase morphology sea-island structure (one phase are dispersed in the matrix in the form of isolated droplets, rods, or platelets) and co-continuous structure (usually formed in dual blends). 

Most utility polymeric articles available today contain multiphase polymeric systems comprised of semi-crystalline polymers, copolymers, polymers in solution with low molar mass compounds, physical laminates or blends. The primary aim of using multicomponent systems is to mould the properties available from a single polymer to another set of desirable material properties. The property development process is complex and depends not only on the properties of the polymer(s) and other components but also on the formation process of the system which determines the developed microstmcture, and component interaction after formation. Moreover, the process of polymer composite formation and the stability of the composite is a function of environmental parameters, e.g., temperature, presence of other species etc. The chemical composition and some insight into the microscopic structure of constituents in a polymer composite can be directly obtained using Infrared (IR) spectroscopy. In addition, a variety of instrumental and sampling configurations for spectroscopic measurements combine to make irrfra-red spectroscopy a versatile characterization technique for the analysis of the formation processes of polymeric systems, their local structure and/or dynamics to relate to property development under different environmental conditions. In particular, Fourier transform infrared (FTIR) spectroscopy is a well-established technique to characterize polymers [1, 2]. 

Many polymeric materials of academic and industrial interest are multicomponent polymers that have multiple phases in the bulk. Control over the composition and size distribution of the domains and their interface properties is often very important in determining the materials properties. A variety of blends and multiphasic polymers have already been investigated with nexafs microscopy. These include studies of... 

It is the intent of this doeument to define the terms most commonly encountered in the field of polymer blends and eomposites. The scope has been limited to mixtures in which the eomponents differ in ehemical composition or molar mass or both and in which the continuous phase is polymeric. Many of the materials described by the term multiphase are two-phase systems that may show a multitude of finely dispersed phase domains. Hence, incidental thermodynamic descriptions are mainly limited to binary mixtures, although they can be and, in the scientific literature, have been generalized to multicomponent mixtures. Crystalline polymers and liquid-crystal polymers have been considered in other documents [1,2] and are not discussed here. 

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