Graft copolymer nomenclature

Because of the above considerations, Sperling and co-workers (12, 13) have evolved a tentative nomenclature scheme for polymer blends, isomeric graft copolymers, and IPNs, and have gradually broadened and clarified the system. However, a certain level of achievement has been attained, and even though the proposed system still has faults, it will be presented below. 

Block Copolymers. As illustrated in Figure 3, block copolymers represent a special kind of graft copolymer, i.e., polymer n + 1 is always attached at the end of polymer n. This mode of attachment will be designated as a line (L) junction. (The writer is indebted to Charles E. Rogers of Case Western Reserve University for suggesting L-junction nomenclature.) A simple, two-component block copolymer can then be represented by ... 

Ceresa, R. J., Block and Graft Copolymers, Nomenclature Section, Butter-... 

Graft copolymers like 1-27 are named aspoly(A-g-B) with the backbone polymer mentioned before the branch polymer. Examples are poly(ethylene- -styrene) or starch-g-polystyrene. In block copolymer nomenclature b is used in place of g and the polymers are named from an end of the species. Thus the triblock macromolecule 1-53... 

Graft copolymers of A and B monomers are named poly(A-g-B) or poly -graft-po y B with the backbone polymer -(-A-) - mentioned before the branch polymer. Some examples are poly(ethylene-g-styrene) or polyethylene-gra/it-polystyrene and starch-gra/ir-polystyrene. In the nomenclature of block copolymers, b or block is used in place of g or graft, e.g. poly(A-b-B) or poly A-block-poly B, poly(A-6-B-6-A) or poly A-6/ocik-poly B-blocic-po y A, poly(A-b-B-6-C) or poly A-6/ock-poly B-block-po y C), and so on. Thus the triblock polymer (XXIV) is called poly(styrene-6-butadiene-b-styrene) or polystyrene-6/ocA -polybutadiene-6/ock -polystyrene. When such polymers are articles of commerce they are usually designated by the monomer initials thus, structure (XXIV) would be named SBS block copolymer. 

Branched chains formed of a main chain of homopolymer of one monomer type and one or several branches of homopolymer of a second monomer type are called graft copolymers, they are illustrated in Figure 6.5. The nomenclature for these copolymers is polyA-.gra/r-polyB [24]. They are sometimes referred to as poly(A-.gra/r-B). Chapter 10 reviews the topic of graft copolymers, and the reader is also referred to the review by Hadjichristidis [25] for example. CRP has also been used to synthesize this kind of polymer via NMP [26], ATRP [27], and RAFT [28]. 

The prefix g describes graft copolymers and the prefix b describes block copolymers. In this system of nomenclature, the first polymer segment corresponds to the homopolymer or copolymer that was formed during the first stage of the synthesis. Should this be a graft copolymer then this will represent the backbone polymer. For instance, if polystyrene is graft copolymerized with polyethylene, the product is called poly(ethylene-g-styrene). A more complex example can be poly (butadiene-co-styrene-g-acrylonitrile-co-vinylidine chloride). Similarly, examples of block copolymers would be poly(acrylonitrile- -methyl methacrylate) or poly(methyl methacry late- -acry lonitrile). 

The regular copolymers require additional structure information. Three simple examples are listed with their nomenclature in Fig. 1.19. While alternating copolymers also need only information on the concentration for full characterization, more detail is needed for block and graft copolymers. The number and length of the blocks or grafted chains and their possible distributions within and between the molecules must be known for full structural characterization. 

The most convenient polymeric surfactants are those of the block and graft copolymer type. A block copolymer is a linear arrangement of blocks of variable monomer composition. The nomenclature for a diblock is poly-A-block-poly-B, and for a triblock it is poly-A-block-poly-B-poly-A. One of the most widely used triblock polymeric surfactants are the Pluronics (BASF, Germany) or Synperordc PE (ICI, U.K.), which consists of two poly-A blocks of poly(ethylene oxide) (PEO) and one block of poly(propylene oxide) (PPO). Several chain lengths of PEO and PPO are available. More recently, triblocks of PPO-PEO-PPO (inverse Pluronics) became available for some specific applications. 

The previous two chapters briefly described a number of two-polymer combinations polymer blends, blocks, grafts, and IPNs. A few somewhat more complicated systems were alluded to blends of a homopolymer with a block copolymer, or a mixture of a graft copolymer with one or both homopolymers. This chapter will explore some of the more complex (and interesting) structures, and provide a nomenclature scheme where one now does not exist. ... 

L. H. Sperling, Isomeric Graft Copolymers and Interpenetrating Polymer Networks. Current Status of Nomenclature Schemes, in Chemistry and Properties of CrosslinkedPolymers, S. S. Labana, ed., Academic, New York (1977). Group theory concepts applied to polymer blends, grafts, blocks, and IPNs. Nomenclature scheme. 

L. H. Sperling and K. B. Ferguson, Isomeric Graft Copolymers and Interpenetrating Polymer Networks. Possible Arrangements and Nomenclature, Macromolecules 8(6), 69 (1975). Graft copolymer and IPN nomenclature scheme. Application of group theory concepts. 

A simple graft copolymer can be represented as Ak-gra/i-Bm or polyA-gra/i -polyB or poly(A-g-B), where Ak or polyA is the backbone to which the B or polyB branches are grafted. The nomenclature of graft copolymers follows the rules recommended by the lUPAC Commission on Macromolecular Nomenclature (2). 

The classi cation of copolymers according to structural types and the nomenclature for copolymers have been described previously in Chapter 1. The present chapter is primarily concerned with the simultaneous polymerization of two monomers by free-radical mechanism to produce random, statistical, and alternating eopolymers. Copolymers having completely random distribution of the different monomer units along the copolymer chain are referred to as random copolymers. Statistical copolymers are those in which the distribution of the two monomers in the chain is essentially random but in uenced by the individual monomer reactivities. The other types of copolymers, namely, graft and block copolymers, are not synthesized by the simultaneous polymerization of two monomers. These are generally obtained by other types of reactions (see Section 7.6). 

Head-to-tail links, -CH2-CHCI-CH2-CHCI-, can be observed as well as head-to-head or tail-to-tail links, -CH2-CHCI-CHCI-CH2-CH2CHCI-. In copolymers, the situation becomes even more complex because the individual monomers can combine in many different ways resulting in statistical, random, alternating, periodic, block, and graft copolymers. As mentioned in Section 1.18.1, this situation required the development of a structure-based nomenclature and a source-based nomenclature system. 

Used in graft copolymer nomenclature to describe the chain onto which the graft is formed. 

Block and graft copolymers are mostly referred to in the following by abbreviation of their segments, such as PS-b-PEO for polystyrene-block-poly(ethylene oxide) and PS-g-PEO for polystyrene-graft-poly(ethylene oxide) or more simply PS-PEO if the type of copolymer is clearly specified. Full names of the copolymers discussed in the text are provided in the nomenclature. 

In the international nomenclature, -co-, -alt-, -b-, -g- are often inserted between two monomers to represent random copolymerization, alternating copolymerization, block copolymerization, and graft copolymerization, respectively. In random copolymer names, the former is the main monomer, and the latter is the secondary monomer. In block copolymer names, the order of monomers represents the order of polymerization, whereas in graft copolymer names, the former is the main chain and the latter is the branched chain. 

The data tables in each chapter are provided there in order of the names of the polymers. In this data book, mostly source-based polymer names are applied. These names are more common in use, and they are usually given in the original sources too. For copolymers, their names were usually built by the two names of the co-monomers which are connected by -co-, or more specifically by -alt- for alternating copolymers, by -b- for block copolymers, by -g- for graft copolymers, or -stat- for statistical copolymers. Stmcture-based names, for which details about their nomenclature can be fonnd in the Polymer Handbook (1999BRA), are chosen in some single cases only. CAS index names for polymers are not appUed here. Finally, a list of the polymers in Appendix 1 ntilizes the names as given in the chapters of this book. 

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