Molecular chains alkanes, applications

An interesting application of the molecular dynamics technique on single chains is found in the work of Mattice et al. One paper by these authors is cited here because it is relevant to both RIS and DRIS studies and deals with the isomerization kinetics of alkane chains. The authors have computed the trajectories for linear polyethylene chains of sizes C,o to Cioo- The simulation was fully atomistic, with bond lengths, bond angles, and rotational states all being variable. Analysis of the results shows that for very short times, correlations between rotational isomeric transitions at bonds i and i 2 exist, which is something a Brownian dynamics simulation had shown earlier. 

Today, commerical CP formulations are synthesized by the crude chlorination of -alkane feedstocks with molecular chlorine under forcing conditions, e.g., high temperatures and/or UV irradiation. The extent and conditions of the chlorination employed ultimately depend on the desired application [1,3]. Because the n-alkane feedstocks are derived from petroleum fractions, the end product is a mixture of carbon chain lengths and chlorination. Commercial CP mixtures fall into three categories C10-C13 (short), C14-C17 (medium), and C20-C30 Gong). The mixtures are further subcategorized on the basis of their weight content of chlorine 40-50%, 50-60%, and 60-70%. 

Maron SH, Nakajima N (1959) A theory of the thermodynamic behavior of non-electrolyte solutions. II. Application to the system mbber-benzene. J Polym Sci 40 59-71 Maron SH, Nakajima N (1960) A theory of the thermodynamic behavior of non-electrolyte solutions. III. The osmotic pressure of polymer solutions. J Polym Sci 42 327-340 Orwall RA, Flory PJ (1967) Equation-of-state parameters for normal alkanes. Correlation with chain length. J Am Chem Soc 89 6814—6822 Prigogine I (1957a) The molecular theory of solution. North-Holland, Amsterdam Prigogine I (1957b) Molecular theory of solutions. Chapter 16. North-Holland, Amsterdam Rowlinson JS (1970) Structure and properties of simple liquids and solutions. Faraday Disc Chem Soc 49 30-42... 

The strongest effort by our group and by other authors was aimed at revealing the structure and molecular dynamical evolution of the very many classes of technologically and scientifically relevant molecules consisting of n-alkanes or n-alkyl long chains. We report below some of the results obtained and will show some applications. 

---