Polymer conventional nomenclature

Over the years, four generations of membrane materials have been appeared in the market. The first generation comprised cellulosic materials, the second included polymeric materials, the third was mainly from inorganic materials, and the fourth is based on carbon fibers. Conventional nomenclature of UF membranes includes two prefix letters (e.g., UM, PM, and XM) that refer to different polymers, and two last digits which indicate... 

Other reviews of multidimensional separations have been published. These include a book on polymer characterization by hyphenated and multidimensional techniques (Provder et al., 1995), a review on polymer analysis by 2DLC (van der Horst and Schoenmakers, 2003), and two reviews on two-dimensional techniques in peptide and protein separations (Issaq et al., 2005 Stroink et al., 2005). Reviews on multidimensional separations in biomedical and pharmaceutical analysis (Dixon et al. 2006) and multidimensional column selectivity (Jandera, 2006) were recently published. Suggested nomenclature and conventions for comprehensive multidimensional chromatography were published in 2003 (Schoenmakers et al., 2003), and a book chapter in the Advances in Chromatography series on MDLC was published in 2006 (Shalliker and Gray 2006). 

The CRU is named using replacement nomenclature ( a nomenclature) [3,8], N.B. In replacement a nomenclature as conventionally applied to acyclic structures with several heteroatoms, terminal heteroatoms are not designated with a prefixes but are named as characteristic groups of the structure, i.e., as hydroxy, amino, carboxylic acid, etc. However, heteroatoms in such positions within the CRUs of ladder or spiro polymer molecules are not terminal units and the stmctures are not acyclic. Consequently, such atoms are designated with a prefixes, and thereby the simplicity afforded by the application of replacement nomenclature to polymer molecules is enhanced. 

While different nomenclature conventions and historical discontinuities are at best confusing to the human searcher, they lead to serious problems in terms of multiple registration of entities in registration systems as well as information compartmentalization a mapping of polybutadiene onto poly(but-l-ene-l,4-diyl) is not straightforward for a human and even less so for a machine (polybutadiene does not indicate the position of the double bond in the polymer backbone) and therefore any data associated with either registration may or may not be equivalent. 

In conventional organic nomenclature, a polymer is not considered to be an isomer of the repeating molecular unit, because the molecular formulas formally differ. This is a somewhat arbitrary distinction, however, because it is never really an isolated, single molecule of monomer that is compared with the polymer. In an aggregate of monomer molecules, intermolecular forces exist and the constitutional difference from an aggregate of polymer molecules is simply that some intermolecular forces have been converted into true chemical bonds. In any case, the term polymerization isomerism has had a long-standing use in coordination chemistry. It may refer... 

Multiarm star (co)polymers can be defined as branched (co)polymers in which three or more either similar or different linear homopolymers or copolymers are linked together to a single core. The nomenclature that will be used follows the usual convention ... 

This brief review has emphasized the exceptions more than the regularities of the conventional polymer nomenclature. The reader will find that this jargon is not as formidable as it may appear to be on first encounter. A very little practice is all that is usually needed to recognize repeating units, parent monomer structures, and the common names. 

Physically persistent stabilizers classified as functionalized oligomers or polymers can be synthesized by polyreactions of functionalized monomers and/or by polymer analogous reactions exploiting the reactivity of functionalized reactive low molecular weight compounds with polymeric substrates. For a detailed classification of synthetical approaches, the classification principle used in Houben-Weyl [42] was adopted. The nomenclature of functionalized polymers is based on the monomer s unit principle. Abbreviations of conventional polymers are used as recommended by [1, 2]. 

Since there are no codified rules for the common naming system, this brief review has outlined the general practice which applies to most polymers. It has also highlighted several exceptions where the system breaks down or inconsistencies occur in which case resort is made to generally accepted conventions for assignment of names to particular polymers. The common nomenclature is thus arbitrary in the final analysis. 

The vectors k are 3D, 2D, or ID for a crystal, slab, or periodic polymer respectively. Keep in mind that the nomenclature nD refers to the number of cartesian directions in which nuclei have periodic ordering. The electron density is three-dimensional, as is r, whatever the system periodicity. Thus, when we treat an ultra-thin film (UTF) with GTOFF, we are not doing a super-cell calculation on a fictitious crystal consisting of the UTF interspersed by layers of vacuum . GTOFF can do such super-cell calculations but more importantly, it can handle the UTF as a fi ee-standing object periodic in two Cartesian directions and of finite thickness in the third direction (conventionally z), subject to vacuum boundary conditions in z. Note also that a 2D GTOFF calculation does not require inversion s)mimetry with respect to z, hence can treat an even number of nuclear planes as readily as an odd number. 

The Environmental Protection Agency (EPA) explained the conventions applied to listings of polymeric chemical substances for purposes of Premanufacture Notification (PMN) reporting and the TSCA Inventory. The principal guidance document in which the conventions are explained is titled Toxic Substances Control Act Inventory Representation for Polymeric Substances, which was published on 29 March 1995. This discussion of polymer nomenclature conventions under TSCA begins with general guidelines, followed by a discussion of how polymers are identified... 

The nomenclature poly (M1-6-M2) is used where Mj and M2 are the monomer names for example poly (styrene-b-butadiene). To make block copolymers, the polymer chains must have the ability to propagate [living polymers) when the first monomer is replaced by the second. In conventional addition polymerisation the chain termination and transfer processes make the lifetime of a growing polymer chain too short. Consequently, special ionic polymerisation catalysts were developed. A fixed number of di-anions such as [C6H5CHCH2CH2CHC6H5] are introduced into an inert solvent. These propagate from both ends if a suitable monomer is introduced. As there are no termination or transfer reactions, once the first monomer has been consumed, a second monomer can be introduced to produce a triblock copolymer such as styrene-butadiene-styrene. Each block has a precisely defined molecular weight. These materials undergo phase separation (Chapter 4) and act as thermoplastic rubbers. 

The publication by Chiang et al. [1] led to a huge surge in interest in synthetic metals. In less than a decade, most of the monomer building blocks that we know today had been identified and many procedures for polymeric synthesis had been established. The chemical structures are illustrated in Figure 1.1. (In the nomenclature used in Figure 1.1, polyacetylene would be called polyvinylene. This is because some - common - names derive from the compound that is polymerized, while others, more correctly according to lUPAC conventions, use the monomeric unit in the product polymer.)... 

Storage of Polymer Structures. CAS has developed comprehensive sets of nomenclature rules and structure conventions that have become standards in the world of chemical literature (see Chemical Abstracts Service Information System). CAS selects polymers for indexing according to a set of rules (5). The Registry File records are created from chemical information published in books, patents, dissertations, scientific journal articles, etc. 

The first extensive lUPAC publications on stereochemistry in high polymers were published in the early 1960s, and subsequently in 1966 as a single article (39). In addition to more conventional polymer names, eg, polyethylidene and polypropylene, the -amer nomenclature was introduced in 1952 (10). lUPAC basic definitions relating to stereochemistry, eg, tacticity and isotactic polymer, were published in 1974 (1). 

Names for specific polymers which derive from the names of the parent monomers are described as source-based. Most efforts of the lUPAC have been made to develop structure-based names, but source-based names are allowed and the nomenclature for copolymers is source-based. By convention, the name of a homopolymer is the name of the parent monomer, prefixed by poly . If the monomer name consist of more than one word, and for names containing substituents, parentheses are used for example poly(vinyl chloride), poly(tetrafluoroethylene). Also hypothetical monomers can be found in source-based names if the polymer is formed by modification of another polymer (for example poly (vinyl alcohol) which is obtained from modification of poly(vinyl acetate)). Examples for source-based names are given in Table 5.3.1 together with their corresponding structure-based names. Furthermore, common names may be used for monomers which are also used in the corresponding polymer name (see Table 5.3.2). ... 

For daily work and for the purpose of this book, CAS Registry Numbers are not very significant. The specification of data for polymers is based on their conventional names, following nomenclature rules as described in Sect. 5.2, 5.3, and 5.4. For most of the polymers appearing in this book, CAS Registry Numbers can be found in Table 5.5.2. 

There is no official classification system. However, the nomenclature convention of SIS, SBS, SEES, and SEPS, which Shell (now Kraton Polymers EEC) set up, is widely used. 

---