Polymer structure-based

With the idea of extending the scope of the macromolecular engineering of aliphatic polyesters, the coordination-insertion ROP of lactones and dilactones has been combined with other polymerization processes. This section aims at reviewing the new synthetic routes developed during the last few years for building up novel (co)polymer structures based on aliphatic polyesters, at least partially. 

In addition to the opportunities for new materials synthesis and characterization along these lines, transport properties, rheology, and processing techniques for liquid crystal polymers are essentially unexplored. Experiences with synthesis of polymer structure based on these liquid crystal templates may open up other creative avenues for template synthesis, for example, inside other crystalline structures, chlathrates, or zeolites, or on surfaces [4], Composites, alloys, or mixtures of liquid crystalline and flexible polymers may produce new materials. 

Our research group has devoted itself to the investigation of the polymerization mechanism, especially in stereoregular polymerization, and to the control of polymer structure based on an understanding of the polymerization reaction. Well aware of the importance of detailed structural analysis of polymers in these studies, we have realized that NMR spectroscopy is the best tool for this purpose. This has encouraged us for a long time to commit to NMR spectroscopy of polymers. This chapter consists of several topics from our research work selected from the viewpoint described above. 

Hydrocarbon Structures. Early postulates of asphaltene structure centered around a variety of polymer structures based on aromatic systems (36, 37). More recent information has related to the structural parameters and carbon skeleton of petroleum fractions, and asphaltenes structures have been derived from spectroscopic studies of asphaltenes isolated from various petroleum and bitumen (38-46). 

Polymer-on-Polymer Structures Based on Radiation Grafting... 

As will be evident from the following discussion, the variety of polymer structures based on a phosphorus-nitrogen skeieton far exceeds those that are accessible in the... 

Post-polymerisation modifications of polymer structures based on the thiol-ene reaction are important tools in macromolecular science because several thiol compounds bearing diverse functional groups can be introduced easily onto a polymer chain that bears non-activated mono-substituted double bonds as functional groups... 

Regular Double-Strand (Ladder and Spiro) Organic Polymers. Structure-based and source-based nomenclature rules have been extended to regular double-strand (ladder and spiro) organic polymers (18). A doublestrand polymer is defined as a polymer, the molecules of which are formed by an uninterrupted sequence of rings with adjacent rings having one atom in common (spiro polymer) or two or more atoms in common (ladder polymer). 

Principles and Characteristics Simultaneous thermal analysis techniques, such as TG-DSC/DTA offer vital information on polymer structure based on heat flow behaviour and mass change [290], but little direct information on the composition of evolved gas products. A more complete thermal profile is provided when a thermal analyser is coupled to an identification tool. Henderson et al. [433] have recently described TG-DSC/DTA with evolved gas analysers (MS and FTIR). The skimmer coupling is the most advanced commercial way of combining a thermobalance or simultaneous TG-DSC/DTA instrument with a quadrupole mass spectrometer [338]. For descriptions of interface techniques in this coupled instrumentation, cfr. ref. [411]. Simultaneous TG-DSC-MS is capable of operation up to 2000°C [434]. 

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