Polyethylene naphthalate (poly(ethylene 2,6-naphthalate) or PEN) is a polyester derived from naphthalene-2,6-dicarboxylic acid and

ethylene glycol Ethylene glycol ( IUPAC name: ethane-1,2-diol) is an organic compound (a vicinal diol) with the formula . It is mainly used for two purposes, as a raw material in the manufacture of polyester fibers and for antifreeze formulations. It is an od ...

. As such it is related to poly(ethylene terephthalate), but with superior barrier properties.

Production

Two major manufacturing routes exist for polyethylene naphthalate (PEN), i.e. an ester or an acid process, named according to whether the starting monomer is a diester or a diacid

derivative In mathematics, the derivative of a function of a real variable measures the sensitivity to change of the function value (output value) with respect to a change in its argument (input value). Derivatives are a fundamental tool of calculus. ...

, respectively. In both cases for PEN, the glycol monomer is ethylene glycol. Solid-state polymerization (SSP) of the melt-produced resin pellets is the preferred process to increase the average molecular weight of PEN.

Applications

Because it provides a very good oxygen barrier, it is well-suited for bottling beverages that are susceptible to oxidation, such as

beer Beer is one of the oldest and the most widely consumed type of alcoholic drink in the world, and the third most popular drink overall after water and tea. It is produced by the brewing and fermentation of starches, mainly derived from cer ...

. It is also used in making high performance sailcloth. Significant commercial markets have been developed for its application in textile and industrial fibers, films, and foamed articles, containers for carbonated beverages, water and other liquids, and thermoformed applications. It is also an emerging material for modern electronic devices. * PEN was the medium for Advanced Photo System film (discontinued in 2011). * PEN is used for manufacturing high performance fibers that have very high modulus and better dimensional stability than PET or Nylon fibers. * PEN is used as the substrate for most Linear Tape-Open (LTO) cartridges. It also has been found to show excellent scintillation properties and is expected to replace classic plastic

scintillator A scintillator is a material that exhibits scintillation, the property of luminescence, when excited by ionizing radiation. Luminescent materials, when struck by an incoming particle, absorb its energy and scintillate (i.e. re-emit the absorbe ...

Benefits when compared to polyethylene terephthalate

The two condensed aromatic rings of PEN confer on it improvements in strength and modulus, chemical and hydrolytic resistance, gaseous barrier, thermal and thermo-oxidative resistance and ultraviolet (UV) light barrier resistance compared to polyethylene terephthalate (PET). PEN is intended as a PET replacement, especially when used as a substrate for flexible integrated circuits.

References

{{DEFAULTSORT:Polyethylene Naphthalate Polyesters Plastics ja:ポリエステル#ポリエチレンナフタレート