Structure microstructure molecular

Scale Product Machine Product micro (structure) Product molecular microstructure... 

Olsson, C., Frigard T., Andersson, R., and Hermansson, A.M. (2003). Effects of amylopectin structure and molecular weight on microstructural and rheological properties of mixed B-lactoglobulin Biomacromolecules, A, 1400-1409. 

Because of the significant difference in polymerization characteristics, emulsion and solution processes produce SBR with a different balance of properties. These differences are a result of the molecular structure, branching, molecular weight distribution, and microstructure. In general, the solution SBR process provides a higher capability to modify the molecular parameters. 

The text is divided into four sections. The early chapters cover the physical structure and molecular configuration of the polymer materials which are the basic materials of plastics. It shows how the microstructure of the materials leads to the observed physical and chemical properties and develops the basic relationships between the response of the materials and the applied stresses. 

Alkyllithitim-initiated, anionic polymerization of vinyl monomers is a very useful synthetic method since the major variables affecting polymer properties can generally be controlled, e.g., molecular weight, molecular weight distribution, copolymer structure and composition, configurational microstructure, molecular architecture, and chain-end functionality. This control is a direct consequence of the fact that in the absence of reactive impurities many of these polymerizations are termination and chain transfer free therefore, the products of these polymerizations are living polymers" with carbanionic chain ends. 

Thus, polymers are not simple materials and articles fabricated from them are often complex formulations. The base polymer may vary in microstructure, molecular weight, molecular weight distribution, and structural defects and... 

Returning to the data of Table 7.1, it is apparent that there is a good deal of variability among the r values displayed by various systems. We have already seen the effect this produces on the overall copolymer composition we shall return to the matter of microstructure in Sec. 7.6. First, however, let us consider the obvious question. What factors in the molecular structure of two monomers govern the kinetics of the different addition steps This question is considered in the few next sections for now we look for a way to systematize the data as the first step toward an answer. 

The type of manufacturing process, reaction conditions, and catalyst are the controlling factors for the molecular structure of the polymers [4-8]. The molecular features govern the melt processability and microstructure of the solids. The formation of the microstructure is also affected by the melt-processing conditions set for shaping the polymeric resin [9]. The ultimate properties are, thus, directly related to the microstructural features of the polymeric solid. 

One may now ask whether natural systems have the necessary structural evolution needed to incorporate high-performance properties. An attempt is made here to compare the structure of some of the advanced polymers with a few natural polymers. Figure 1 gives the cross-sectional microstructure of a liquid crystalline (LC) copolyester, an advanced polymer with high-performance applications [33]. A hierarchically ordered arrangement of fibrils can be seen. This is compared with the microstructure of a tendon [5] (Fig. 2). The complexity and higher order of molecular arrangement of natural materi-... 

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