enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Polyester - Wikipedia

    en.wikipedia.org/wiki/Polyester

    When melting points of the monomers are sufficiently low, a polyester can be formed via direct esterification while removing the reaction water via vacuum. Direct bulk polyesterification at high temperatures (150 – 290 °C) is well-suited and used on the industrial scale for the production of aliphatic, unsaturated, and aromatic–aliphatic ...

  3. Polyhydroxyalkanoates - Wikipedia

    en.wikipedia.org/wiki/Polyhydroxyalkanoates

    They can be either thermoplastic or elastomeric materials, [citation needed] with melting points ranging from 40 to 180 °C. [ citation needed ] The mechanical properties and biocompatibility of PHA can also be changed by blending, modifying the surface or combining PHA with other polymers, enzymes and inorganic materials, making it possible ...

  4. Polyhydroxybutyrate - Wikipedia

    en.wikipedia.org/wiki/Polyhydroxybutyrate

    Melting point 175 °C., and glass transition temperature 2 °C. Tensile strength 40 MPa , close to that of polypropylene. Sinks in water (while polypropylene floats), facilitating its anaerobic biodegradation in sediments.

  5. Polymer - Wikipedia

    en.wikipedia.org/wiki/Polymer

    A polymer (/ ˈ p ɒ l ɪ m ər / [4] [5]) is a substance or material that consists of very large molecules, or macromolecules, that are constituted by many repeating subunits derived from one or more species of monomers. [6]

  6. Polycaprolactone - Wikipedia

    en.wikipedia.org/wiki/Polycaprolactone

    Polycaprolactone (PCL) is a synthetic, semi-crystalline, biodegradable polyester with a melting point of about 60 °C and a glass transition temperature of about −60 °C. [2] [3] The most common use of polycaprolactone is in the production of speciality polyurethanes.

  7. Polymer chemistry - Wikipedia

    en.wikipedia.org/wiki/Polymer_chemistry

    Polymer chemistry is a sub-discipline of chemistry that focuses on the structures, chemical synthesis, and chemical and physical properties of polymers and macromolecules. The principles and methods used within polymer chemistry are also applicable through a wide range of other chemistry sub-disciplines like organic chemistry , analytical ...

  8. Melting point - Wikipedia

    en.wikipedia.org/wiki/Melting_point

    The melting point (or, rarely, liquefaction point) of a substance is the temperature at which it changes state from solid to liquid. At the melting point the solid and liquid phase exist in equilibrium. The melting point of a substance depends on pressure and is usually specified at a standard pressure such as 1 atmosphere or 100 kPa.

  9. Polybutylene terephthalate - Wikipedia

    en.wikipedia.org/wiki/Polybutylene_terephthalate

    It is a thermoplastic (semi-)crystalline polymer, and a type of polyester. PBT resists solvents, shrinks very little during forming, is mechanically strong, is heat-resistant up to 150 °C (or 200 °C with glass-fibre reinforcement), and can be treated with flame retardants to make it noncombustible.