9.9 Polyamidees: natural and nylon.
The naturally occurring polymer is protein, a wide variety of tis biological macromolecules make up our skin, hair, muscle, and enzymes. All proteins arepolyamides which are polymers of amino acids. The amine and acid groups are attached to the same carbon atom in addition a hydrogen atom and other group (represented by R) are bonded to that carbon aswell.
The 20 amino acids found in most proteins differ in the identity of their R groups , in some amino acids R consist of crbon and hydroge atoms, as in alanine.Where R is a methyl group. In othersR also includes oxygen, nitrogen, or sulfur atoms. Some R groups are acidic and others are basic, the amino acids are the monomers from protein polymerization.
A peptide bond forms between theremaining portions of the two amino acids. In the biological cells, this condensation reaction is repeated many times over to from long polymeric protein chains . Given the fac that proteins can besynthesized. Some proteins are made up hundreds of amino acids whereas others, like the hormone oxytocine, contain only eight. Note that molecule of a adipic acid has an amine group on each end . As inthe case of protein synthesize the acid amine group react to eliminate water and from peptide bonds.
The petroleum is the source of the monomers used to make most syntetic polymers.Crude oil is a mixture of many compounds that is refined into various fractions on te basis of boiling point and molar mass. Its important to note that chemistry may rescue society from tis dilemma.In principle, at least, polymers can be made from any carbon containing starting material. Crude oilis simply the most convenient and the most economical but to transform biomass into synteticpolymers, new methods and new technologies would have to be developed, muc of the plastic that we use eventually ends up in a landfill, along wit lots of other types of municipal and domestic solid...
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