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Breaking News……….

Commercial Introduction of:  “POLYETHYLENE FURANOATE”  (PEF)

2,6-furandicarboxylic acid (FDCA) is the equivalent acid to PTA that is reacted with MEG to form PEF polymer.

“PEFerence” is a consortium of 11 companies was formed to develop and introduce PEF contaners on a commercial basis. FDCA is made from renewable raw materials and as a polymer, its performance properties (mechanical strength & gas barrier) are superior to those of standard PET. European approval received for disposal of containers through existing recovery systems same as for PET bottles.

More to follow in future ………. FYI

Post on 7/1/2017


When the world thinks of plastic films, it thinks: 

“PET”

Polyester Film is ideally suited for a wide range of uses such as packaging, printing, die-cutting, electronics, protective overlay, barrier protection, apparel and other industrial applications. Because of Polyester Film inherent physical properties, it’s your best choice for a high performance plastic film/sheet.

Polyester Film Manufacturing and Technology

Below is a brief explanation of the standard extrusion process used in manufacturing polyester film.

  • Polyester polymer grades (made in continuous process or batch reactors) are extruded onto casting drum (gives ultra smooth surface to plastic film).
  • Film is stretched in forward and transverse directions.
    • Sequential Draw process: the film’s forward draw is over a series of precision motorized rollers; transverse or sideways draw uses diverging clips in a multiple zoned oven with tightly controlled temperatures.
    • Simultaneous Draw process: the film is drawn using precision controlled simultaneously diverging, and accelerating clips through a multiple zoned oven with tightly controlled temperatures.
    • In all processes, tension and temperatures are critical to final quality of the film.
  • Sophisticated scanners and control systems maintain process conditions at optimal point.
  • Advanced structures are made by extruding layers of polymer simultaneously and coating film as it is stretched.
  • Film is wound into large master rolls (can be slit to precision widths before delivery to customer).
  • Film thicknesses typically range from 1 micron to 350 microns.
  • Each asset usually designed for narrow range of thicknesses.
    • Offering complete range of films requires heavy investment in multiple lines (from $50 million up per line).

 

Process Flow

 

polymer structure

Polyester film is a high-performance film made from polyethylene terephthalate (PET) resin. The Polyethylene Terephthalate (PET) resin is made from Ethylene Glycol and dimethyl terephthalate (DMT). The PET resin used is of a similar intrinsic viscosity (IV) to fiber grade resin, used to produce polyester fibers with high purity.

In comparison with other common plastic films, polyester film is characterized by high tensile strength, excellent dimensional stability, low moisture absorption, good retention of physical properties over a fairly wide temperature range (-70° to 150°C), excellent electrical properties, and good optical clarity. Because of its higher price relative to PVC, polyethylene, and polypropylene film, polyester film is generally considered a specialty film among all plastic films; however, markets of considerable volume have developed that require this strong, dimensionally stable film. Prices are higher than most commercial plastic films primarily because the manufacturing process is much more costly due to the need for an orientation step. (Most polypropylene film is also oriented.)

The strength of polyester film requires rugged machinery for orientation. In order to assure strict gauge control, the buildings containing the film lines are carefully engineered and have very strong foundations and special reinforced flooring to prevent vibrations. Many end uses for polyester film have stringent specifications (e.g., photographic film and magnetic media) and require clean room conditions. Thus, capital costs are much higher than for other oriented films.

Polyester Films have a unique combination of physical, chemical, thermal, and optical properties which result in the following: Strong, tough, brilliant and clear and ease of converting, laminating, extrusion coating, embossing, metallizing, printing, punching, corrugating, dyeing, stamping and forming. Polyester film is sold in various types, thicknesses, widths, and properties designed in many cases to satisfy the requirements of particular end applications.


Clarification of Viscosity Measurements of PET

Intrinsic Viscosity and Viscosity number………

 

Both intrinsic viscosity (IV) and viscosity number (VN) measure the viscosity of a

polymeric solution. VN is also referred to as coefficient of viscosity (CV). Both IV

and VN are related to the average number molecular weight of the polymer.

The polymeric solution is prepared by dissolving the PET polymer in one of

several solvents; most commonly a 50/50 by weight mixture of phenol and 1,2-

dichlorobenzene is used for PET. The viscosity is determined at constant

temperature, usually 25°C.

The Intrinsic Viscosity, usually expressed in dl/g, is defined as:

where:

c concentration of the polymeric solution (in g/dl)

η… viscosity of the solution at concentration c

η0…. viscosity of the solvent

Instead of using the definition, for simplicity’s sake IV is more commonly

determined with the approximate Billmeyer equation:

c

IV rel rel

4*

=h -1+ 3*ln(h )

where:

c… concentration of the polymeric solution (in g/dl); usually, a concentration

of 0.5 g/dl (i.e., 0.005 g/ml) is used

ηrel…. relative viscosity = t/t0

t…. flow time of the solution at concentration c

t0…. flow time of the solvent

 

The Viscosity Number however, usually expressed in ml/g:

As stated previously the Viscosity Number is identical to the Coefficient of

Viscosity.

Whether determining IV by the Billmeyer equation or measuring VN , the flow

time of the polymeric solution and of the solvent is measured in an Ubbelhode

viscometer; the thermostatic bath is set at 25°C. The flow time is

measured starting when the meniscus passes the initial tally and ending when it

reaches the final tally.

The following graph shows the trend of VN versus IV for PET, as calculated from this empirical correlation.

 

Posted on: 05/01/2017