Blend morphology/property relationship

This chapter describes the recent research on the morphologies, properties and morphology-property relationships of a variety of blends having at least one... 

Conza les-Montiel, A., Keskkula, H., and Paul, D. R. 1995. Impact-modified nylon 6/polypro-pylene blends 1. Morphology-property relationships. Polymer 36 4587-4603. 

The control of the phase separation morphology is just a key technology in polymer blends. In order to achieve good performance of the materials, it is important to handle the processing-morphology-properties relationship. 

S. Cimmino, L. D orazio, R. Greco, G. Maglio, M. Malinconico, C. Mancarella, E. Martuscelli, R. Palumbo and G. Ragoista, Morphology-Properties Relationships In Binary Polyamide 6/Rubber blends Influence of the Addition of a Functionalized Rubber, Polymer. Eng, and Sci. 1984, 24, no 1, 48-56. 

Usually, a composite filled with large specific ratio fibers or flakes has a lower percolation threshold than that filled with spherical conductive particles. The fillers with a high aspect ratio may also increase the tendency to form the co-continuous phases in polymer blend matrices [10]. These morphology-property relationships imply that if the conductive filler is preferential, or even totally localized in the minor phase or its surface (a-polymer) of a polymer blend, and the conductive filler/a-polymer blend is elongated or oriented to form conductive in situ microfibrils in the polymer matrix ([3-polymer), the composite obtained may have high conductivity (construction of 3D conductive in situ microfiber... 

In this section of our review, we shall discuss the morphological aspects and structure-property relationships of a few specific copolymeric systems which we think will represent the general features of siloxane containing multiphase copolymers. More detailed discussions about the properties of each copolymer system may be found in the references cited during our review of the copolymer preparation methods. On the other hand an in-depth discussion of the interesting surface morphology and the resultant surface properties of the siloxane containing copolymers and blends will be provided. 

It is important to mention that the structure/properties relationships which will be discussed in the following section are valid for many polymer classes and not only for one specific macromolecule. In addition, the properties of polymers are influenced by the morphology of the liquid or solid state. For example, they can be amorphous or crystalline and the crystalline shape can be varied. Multiphase compositions like block copolymers and polymer blends exhibit very often unusual meso- and nano-morphologies. But in contrast to the synthesis of a special chemical structure, the controlled modification of the morphology is mostly much more difficult and results and rules found with one polymer are often not transferable to a second polymer. 

Su et al. (8) studied the mechanical properties and morphological structure relationship of blends based on sulfated EPDM ionomer and PP. They synthesized Zn neutralized low degree sulfated EPDM (Zn-SEPDM) ionomer and PP blends and studied their mechanical properties. They found that Zn + neutralized low degree sulfated EPDM ionomer and PP blends have better mechanical properties than those of PP/EPDM blend, as shown in Fig. 14.4. They explained the reason why mechanical properties are higher for Zn-SEPDM and PP than for PP and EPDM using scanning electron microscopy (SEM) (Fig. 14.5). Finer dispersed phase size and the shorter interparticle distances are the main reasons for the improved mechanical properties of the PP/EPDM blend. 

The characterization methods used in the analysis of the chemical structure, microstructure, and morphology as well as the physical properties of the nanocomposites are varied. Many of these techniques are specific for characterization of particular properties of nanocomposites, and the properties of nanocomposites are also correspondingly discussed. To fully understand the structure-property relationships, several characterization techniques are often used. The properties of the polymer blend nanocomposites strongly depend on their composition, size of the particles, interfacial interaction, etc [35],... 

Therefore, an understanding of the relationship between recycled polyolefinic blend formulation and processing on one hand and blend morphology and properties on the other should facilitate a more cost-effective approach to product formulation and processing and product design for applications using recycled polyolefins. 

Chandramouli K and Jabarin S A (1995) Morphology and property relationships in ternary blends of PE/PA6/compatibilizing agents, Adv Polym Technol 14 35-46. 

Phase behaviour and erystallisation kinetics for the binaiy blend P(3HB)/ eellulose propionate (CP) were performed by Maekawa et Cellulose aeetate butyrate (CAB), which has a combination of high (160 °C) and Tg (113 °C), is an important thermoplastic cellulose ester that can biodegrade in a natural environment. In an attempt to make the best use of degradable polyester P(3HB), Wang et al. blended P(3HB) with CAB and studied the relationship between the blend morphology and its physieal properties. 

There are several characterization techniques for polymer blend systems in respect of mechanical behaviour, structure-property relationships, phase morphology characteristics and their interaction vs. miscibility or compatibility, and so on. These may be categorized as (i) microscopic techniques (ii) study of glass transition (iii) spectroscopic techniques (iv) scattering methods and (v) viscosity measurements. 

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