Chain uniform

A common example of the Peieds distortion is the linear polyene, polyacetylene. A simple molecular orbital approach would predict S hybddization at each carbon and metallic behavior as a result of a half-filled delocalized TT-orbital along the chain. Uniform bond lengths would be expected (as in benzene) as a result of the delocalization. However, a Peieds distortion leads to alternating single and double bonds (Fig. 3) and the opening up of a band gap. As a result, undoped polyacetylene is a semiconductor. 

Fig. 2. Schematic representation of selected hydrocarbon chains in the crystalline and the amorphous regions of polyethylene, respectively. For ensembles of chains uniformly distributed around the dashed lines the deuterons from planar and conical distributions as indicated...

Linear low-density polyethylene (LLDPE) has enhanced tensile strength for the same density as LDPE. Its density ranges from 0.915 to 0.940 g/cm Film accounts for most of the consumption of this polymer. It is a long linear chain without long side chains or branches. The short chains disrupt the polymer chain uniformity enough to prevent crystalline formation and, hence, prevent the polymer from achieving high densities. LLDPE has production economies compared to LDPE because of lower polymerization pressures and temperatures. 

Polymeric materials are based on both precise control of molecular structure through polymerization and subsequent processing techniques. The necessary requirements for designing and processing of polymeric materials are functionality, composition, topology, and chain uniformity. The structure of polymer materials consists of designed architectures and this property helps accomplish various applications. 

Buist E, Chan W, L Eraiyer P (2008) Speeding up rail ranter simulation and optimization by Markov chain Uniformation. hr Proraeding of the 2008 winter simulation conferenra COPC CSP Stanrlard (2014) The performance management system for customer contact operations... 

In the years following the rise of polymer characterization (the late 0 s and early 50 s), many scientists began to study apparent relations between the properties of linear polymer molecules and the networks obtainable therefrom. This search was also stimulated by the wide range of applications of polymer networks in commercial elastomers thermosets and coatings. Frequently these data were confidently matched with curves obtained from statistically describable models of networks of ghost chains uniformly distributed in space. 

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