From waxes to polymers–the crystallography of polydisperse arrays
This chapter reconsiders the model for petroleum wax structure presented in Chapter 1 in light of the structural information presented in the intervening chapters. The earlier packing model is found to be deficient for various reasons: (a) the expectation that methyl branches can be accommodated into the methylene subcell region, (b) that there can be solvent molecules at the chain layer interfaces, (c) that the type of layer packing is ill-defined. Indeed, single crystal evidence from electron diffraction clearly shows that there can be at least two types of solid solution packing in polydisperse arrays, depending on the absolute breadth of the chain length distribution (but not the polydispersity index). Finally, important areas are indicated where more research is needed, including the determination of unknown crystal structures of rather simple molecules such as the symmetric wax esters.
Keywords: wax crystal structure, chain branching, nematocrystallinity, lamellar waxes, petroleum waxes
Oxford Scholarship Online requires a subscription or purchase to access the full text of books within the service. Public users can however freely search the site and view the abstracts and keywords for each book and chapter.
Please, subscribe or login to access full text content.
If you think you should have access to this title, please contact your librarian.
To troubleshoot, please check our FAQs , and if you can't find the answer there, please contact us .