:: TPX® Characteristics

TPX® Polymethylpentene (PMP) characteristics

TPX®, a 4-methylpentene-1 based polyolefin manufactured solely by Mitsui Chemicals, Inc. is now available in small order lots from Goodfellow.  This lightweight, functional polymer displays a unique combination of physical properties and characteristics due to its distinctive molecular structure.  Like polyolefines TPX® shows excellent chemical resistance, which is better than that of polycarbonate and acrylic.

High heat resistance (melt temperature 236° C)

As TPX® has a melting point of 236ﾟC and a Vicat softening point of up to 185°C it can be used at relatively high temperatures for a polyolefin.

Lowest specific gravity of any known polymer (0.833 g/cc)

TPX® has the lowest density and largest specific volume of any known thermoplastic material and is thought to be close to the theoretical minimum for thermoplastics.  Due to this, components moulded from TPX® will weigh approximately 30% less than the same component moulded in polycarbonate.

Superior steam sterilisation capabilities in regards to moisture absorption

TPX®, a polyolefin, does not absorb water. TPX® requires no drying before moulding and is autoclavable. Consequently, TPX® does not suffer deterioration in physical properties or dimensional changes due to hydrolysis taking place with time. This characteristic is utilised for the applications of animal cages and water tanks in domestic irons, among other things.

Superior transparency to visible light and excellent UV transmission characteristics

TPX®  is transparent and shows excellent light transmission properties.

Superior transmission in the UV range as well as IR than glass and other transparent resins, it is used in cells for optical analysis.

Lower refractive index than other transparent resins

The refractive index of TPX® is only 1.463, which is lower than transparent fluoropolymers or other transparent resins.

High gas and moisture permeability

TPX® has a very high gas permeability (10 times higher than that of PE), which makes it an excellent material for gas separating applications like permeable films, membranes and hollow fibres, as well as fruit and vegetable packaging.

Excellent chemical resistance

TPX®, a polyolefin like polypropylene, shows excellent chemical resistance in comparison with other transparent resins such as polycarbonate and acrylic resin.

Outstanding dielectric properties

Because of its outstanding dielectric properties - ε = 2.1 and tan δ = 0.0008 (at 12 GHz) - TPX® fits very well in the field of high-frequency applications.

Release properties

TPX® has excellent release properties due to its exceptionally low surface tension (24 dyne/cm), which is second only to flouropolymers such as PTFE. Due to this, TPX® is used in the areas of release paper used for release from other materials (urethane and epoxy), release film for printed circuit boards and LED moulds.

Separating Force from Epoxy

Food properties 

Several TPX® grades meet requirements of various Japanese standards tests (JHOSPAS's Positive List and so on), US FDA regulations and EU directives for food packaging. Especially in the microwave oven ware area, TPX® has a good track record in use.

Note: All images, graphs and tables courtesy of Mitsui Chemicals Inc.