Polymer Molecule
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A Polymer Molecule is a macromolecule composed of many repeated subunits.
- Example(s):
- a Protein Molecule, such as hemoglobin or a metalloprotease enzyme.
- a Polyester, a polyactic acid.
- See: IUPAC, Ideal Chain, International Union of Pure And Applied Chemistry, Synthetic Plastic.
References
2017
- (Wikipedia, 2017) ⇒ https://en.wikipedia.org/wiki/Polymer Retrieved:2017-4-30.
- A polymer (Greek poly-, "many" + -mer, "parts") is a large molecule, or macromolecule, composed of many repeated subunits. Because of their broad range of properties, both synthetic and natural polymers play an essential and ubiquitous role in everyday life. Polymers range from familiar synthetic plastics such as polystyrene to natural biopolymers such as DNA and proteins that are fundamental to biological structure and function. Polymers, both natural and synthetic, are created via polymerization of many small molecules, known as monomers. Their consequently large molecular mass relative to small molecule compounds produces unique physical properties, including toughness, viscoelasticity, and a tendency to form glasses and semicrystalline structures rather than crystals. The term "polymer" derives from the ancient Greek word πολύς (polus, meaning "many, much") and μέρος (meros, meaning "parts"), and refers to a molecule whose structure is composed of multiple repeating units, from which originates a characteristic of high relative molecular mass and attendant properties. [1] The units composing polymers derive, actually or conceptually, from molecules of low relative molecular mass. The term was coined in 1833 by Jöns Jacob Berzelius, though with a definition distinct from the modern IUPAC definition. [2] The modern concept of polymers as covalently bonded macromolecular structures was proposed in 1920 by Hermann Staudinger, [3] who spent the next decade finding experimental evidence for this hypothesis. Polymers are studied in the fields of biophysics and macromolecular science, and polymer science (which includes polymer chemistry and polymer physics). Historically, products arising from the linkage of repeating units by covalent chemical bonds have been the primary focus of polymer science; emerging important areas of the science now focus on non-covalent links. Polyisoprene of latex rubber is an example of a natural/biological polymer, and the polystyrene of styrofoam is an example of a synthetic polymer. In biological contexts, essentially all biological macromolecules — i.e., proteins (polyamides), nucleic acids (polynucleotides), and polysaccharides — are purely polymeric, or are composed in large part of polymeric components — e.g., isoprenylated/lipid-modified glycoproteins, where small lipidic molecules and oligosaccharide modifications occur on the polyamide backbone of the protein.
The simplest theoretical models for polymers are ideal chains.
- A polymer (Greek poly-, "many" + -mer, "parts") is a large molecule, or macromolecule, composed of many repeated subunits. Because of their broad range of properties, both synthetic and natural polymers play an essential and ubiquitous role in everyday life. Polymers range from familiar synthetic plastics such as polystyrene to natural biopolymers such as DNA and proteins that are fundamental to biological structure and function. Polymers, both natural and synthetic, are created via polymerization of many small molecules, known as monomers. Their consequently large molecular mass relative to small molecule compounds produces unique physical properties, including toughness, viscoelasticity, and a tendency to form glasses and semicrystalline structures rather than crystals. The term "polymer" derives from the ancient Greek word πολύς (polus, meaning "many, much") and μέρος (meros, meaning "parts"), and refers to a molecule whose structure is composed of multiple repeating units, from which originates a characteristic of high relative molecular mass and attendant properties. [1] The units composing polymers derive, actually or conceptually, from molecules of low relative molecular mass. The term was coined in 1833 by Jöns Jacob Berzelius, though with a definition distinct from the modern IUPAC definition. [2] The modern concept of polymers as covalently bonded macromolecular structures was proposed in 1920 by Hermann Staudinger, [3] who spent the next decade finding experimental evidence for this hypothesis. Polymers are studied in the fields of biophysics and macromolecular science, and polymer science (which includes polymer chemistry and polymer physics). Historically, products arising from the linkage of repeating units by covalent chemical bonds have been the primary focus of polymer science; emerging important areas of the science now focus on non-covalent links. Polyisoprene of latex rubber is an example of a natural/biological polymer, and the polystyrene of styrofoam is an example of a synthetic polymer. In biological contexts, essentially all biological macromolecules — i.e., proteins (polyamides), nucleic acids (polynucleotides), and polysaccharides — are purely polymeric, or are composed in large part of polymeric components — e.g., isoprenylated/lipid-modified glycoproteins, where small lipidic molecules and oligosaccharide modifications occur on the polyamide backbone of the protein.
- ↑ http://goldbook.iupac.org/M03667.html; accessed 7 October 2012. Per the IUPAC Gold Book and PAC sources referenced therein, "In many cases, especially for synthetic polymers, a molecule can be regarded as having a high relative molecular mass if the addition or removal of one or a few of the units has a negligible effect on the molecular properties." However, they note that the "statement fails in the case of certain macromolecules for which the properties may be critically dependent on fine details of the molecular structure."
- ↑ If two substances had empirical formulae that were integer multiples of each other – e.g., acetylene (C2H2) and benzene (C6H6) – Berzelius called them "polymeric". See: Jöns Jakob Berzelius (1833) "Isomerie, Unterscheidung von damit analogen Verhältnissen" (Isomeric, distinction from relations analogous to it), Jahres-Bericht über die Fortschitte der physischen Wissenschaften …, 12 : 63–67. From page 64: "Um diese Art von Gleichheit in der Zusammensetzung, bei Ungleichheit in den Eigenschaften, bezeichnen zu können, möchte ich für diese Körper die Benennung polymerische (von πολυς mehrere) vorschlagen." (In order to be able to denote this type of similarity in composition [which is accompanied] by differences in properties, I would like to propose the designation "polymeric" (from πολυς, several) for these substances.)
Originally published in 1832 in Swedish as: Jöns Jacob Berzelius (1832) "Isomeri, dess distinktion från dermed analoga förhållanden," Årsberättelse om Framstegen i Fysik och Kemi, pages 65–70 ; the word "polymeriska" appears on page 66. - ↑ Staudinger, H. (1920). "Über Polymerisation" (On polymerization), Berichte der deutschen chemischen Gesellschaft, 53 (6): 1073-1085.