Expand Document  |  Expand Chapter  |  Full TOC  |  Printable HTML version
The Graphic Representation of Chemical Formulae in the Publications of International Nonproprietary Names (INN) for Pharmaceutical Substances
(1995; 53 pages) View the PDF document
Table of Contents
View the documentAcknowledgements
View the document1. INTRODUCTION
View the document2. ACYCLIC STRUCTURES
View the document3. CYCLIC STRUCTURES
View the document4. IONIC STRUCTURES
View the document5. ISOTOPICALLY MODIFIED COMPOUNDS
View the document6. COORDINATION COMPOUNDS
View the document7. STEREOCHEMISTRY
View the document8. CARBOHYDRATES
View the document9. STEROIDS
View the document10. TERPENOIDS
View the document11. PROSTANOIDS
View the document12. ALKALOIDS
View the document13. ANTIBIOTICS
View the document14. POLYPEPTIDES
View the document15. POLYMERS
View the documentAcknowledgements
View the documentReferences
 

15. POLYMERS

15.1 The representation of polymers is based on the use of “repeated groups”, i.e. sequences of identical groups. These groups are abbreviated [X]n in square brackets, where n is the number of times that they appear.

15.2 Repeated groups are either “monomers”, i.e. “normal” structural formulae, or “repeated structural units”, which are relatively complex multivalent radicals.

15.3 The normal formulae, i.e. those of the relevant monomers, are used when it is difficult to specify how the monomers are bonded, or in order to show simple oligomers with a maximum of eight repeated groups:

15.4 By and large, polymers are depicted as repeated structural units in which terminal bonds are shown. In linear polymers, such units are bivalent radicals:


polyvidone


polyisoprene


poly (methyl methacrylate)

This also applies to polymers when the terminal groups are shown:


lauromacrogol


dimeticone

15.5 Network polymers can be shown by multivalent repeated structural units:


repagermanium

15.6 The representation of copolymers depends on what is known about the bonding of the constituent monomers. Thus normal formulae are used when it is difficult to specify the way in which the monomers are bonded:


leuciglumer


polyetadene


poliglecaprone

Repeated structural units are used when the atoms involved in bonding are defined. The bonds are represented as unbroken lines between the monomers when their positions are known, but they are shown as unattached when the way in which the monomers are linked has not been precisely determined:


copolymers of ethene and vinyl ethanoate (acetate) (EVA)


polacrilin

15.7 Sequences of polymers are shown in a similar way:


poloxamer

 

to previous section
to next section
 
 
The WHO Essential Medicines and Health Products Information Portal was designed and is maintained by Human Info NGO. Last updated: March 20, 2014