Other Polymers with Saturated Carbon Chain Backbone

9 OTHER POLYMERS WITH SATURATED CARBON CHAIN BACKBONE - General aspects 

Several less common polymers with saturated carbon chain backbone are commercially available and have special practical applications. For example, indene obtained from the coal-tar oil by-products of coking operations can be polymerized by the addition of H2SO4 to form a linear hydrocarbon type polymer with relatively low DP [1-3]. The polymerization of coumarone from the same source generates a similar product, which is used in coatings, adhesives, etc. 

Polymers with saturated carbon chain backbone can be obtained from the polymerization of a variety of unsaturated compounds such as norbornylene, which generates poly(1,3-cyclopentylenevinylene), etc. Other polymers with a saturated carbon backbone can be obtained as copolymers between maleic anhydride and an alkene. Although these types of compounds are technically copolymers, their uniform structure makes them similar to homopolymers such as in the example of poly(ethylene-a/t-maleic anhydride). Formulas of some polymers with saturated carbon chain backbone from this class are shown below  

In addition to the polymers that have a linear carbon backbone, which are still related to polyethylene having various substituents on the carbon chain, other polymers possessing only carbon atoms in the backbone are known, but they have a more complicated structure. For example, the Diels-Alder condensation of a bisdiene and benzoquinone takes place as follows  

The resulting polymer has a carbon chain backbone, but it is different from common vinyl or vinylidene polymers. 

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Polymers with saturated carbon chain backbone include polyolefins, polystyrenes, halogenated polyolefins, halogenated polystyrenes, polyvinyls substituted with various groups such as -OH, -OR, -0(0)C-R, -C(0)0-R, -C(0)-R, -C5H4N, etc. In this class also are included polyacrylates, polymethacrylates, polymers with ketone groups in the backbone, as well as other polymers with saturated carbon chain backbone. The polymers with a saturated carbon chain backbone form the most important and common class of polymers. 

Other polymers with saturated carbon chain backbone... 

Poly(acrylates) and poly(methacrylates) form another class of common polymers with saturated carbon chain backbone. Polyacrylates can be considered vinyl polymers with the -COOR group attached at every other carbon atom in the chain. However, due to their common use and particular properties, polyacrylates form a separate polymer class together with polymethacrylates. Among the most common polymers from this class are those obtained from acrylic acid methyl ester (PMA) and methylacrylic (methacrylic) acid methyl ester (PMMA). Acrylic polymers have many practical applications in automotive industry, in the production of medical materials, paints, coatings and lacquers, adhesives, textiles, and synthetic leather. Poly(methacrylic acid methyl ester) can be obtained in cast sheets with applications in technical components, furniture, building materials, etc. Formulas for poly(acrylic acid), two polyacrylates, and poly(methyl methacrylate) are shown below ... 

Poly(vinyls) substituted with -OH, -O-R, -OC(0)-R, -C(0)-R, -C5H4N, etc. groups form one important class of synthetic polymers having saturated carbon chain backbone. Other polymers derived from the vinyl group with specific substituents such as poly(halogenated olefins), poly(styrenes), poly(acrylates), and poly(methacrylates) form their own classes and are not included here. Examples of polymers known as poly(vinyls) and discussed in this section have formulas as indicated below ... 

The most common backbone structure found in commercial polymers is the saturated carbon-carbon structure. Polymers with saturated carbon-carbon backbones, such as polyethylene, polypropylene, polystyrene, polyvinyl chloride, and polyacrylates, are produced using chain-growth polymerizations. The saturated carbon-carbon backbone of polyethylene with no side groups is a relatively flexible polymer chain. The glass transition temperature is low at -20°C for high-density polyethylene. Side groups on the carbon-carbon backbone influence thermal transitions, solubility, and other polymer properties. 

The simplest polymer with a conjugated backbone is polyacetylene. Its structure is similar to that of the saturated polymer polyethylene, but has one of the hydrogen atoms removed from each carbon of the polyethylene chain. Each carbon atom in the polyacetylene chain thus has one excess electron which is not involved in the basic chemical binding. And if the separation of the carbon were constant, polyacetylene would conduct along the chain in other words it would behave like a metal in one dimension. But unfortunately this is not true as the free electrons tend to get localized in shorter double bonds. Conjugated polymers can at best be expected to display semiconducting properties. 

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