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5882332 
Journal Article 
Chapter 7 Polymers with unsaturated carbon chain backbone 
2005 
1 
Techniques and Instrumentation in Analytical Chemistry
ISSN: 0167-9244 
Elsevier 
Techniques and Instrumentation in Analytical Chemistry 
25 
439-461 
English 
A number of molecules with two conjugated double bonds, such as 1,3-butadiene or 2- methyl-1,3-butadiene (isoprene), can undergo a 1-4 polymerization with the migration of the double bond in the second position. The resulting polymer contains isolated double bonds, but their presence leads to the possibility of having cis- and trans- forms. An important property of the polymers containing carbon–carbon double bonds in the backbone is their capability to be vulcanized. Vulcanization is the process of introduction of some crosslinking bridges between the polymer molecules. It has as a main physical effect a considerable extension of the temperature range where the polymer has good elasticity. The temperatures at which vulcanized elastomer begins to decompose are higher. Other positive effects are achievable by vulcanization, such as an increase in the tensile strength. A different subclass of unsaturated hydrocarbon type polymers is formed by polyacetylenes. This type of polymer contains conjugated double bonds in a linear structure, and because of their special electrical properties, they have been the subjects of numerous studies, including some on thermal stability. Various other polymers have double bonds in their carbon backbone. Some are polyhydrocarbons, such as poly-α-pinene while others are polymers, including aromatic cycles in the backbone or possibly heteroatoms. 
Moldoveanu, Serban C.