A NEW polymer has been introduced by Dotmar EPP that can be used as an economical alternative to costly high performance plastics in a variety of demanding high tech applications.
Even when exposed to chemicals and high temperature environments, the new Techtron HPV PPS thermoplastic offers a multi-purpose combination of properties relative to wear resistance, load-bearing capabilities and dimensional stability.
Dotmar EPP says typical applications for the Techtron HPV PPS series of stock shapes can be found in chemical process equipment (e.g. pump, valve, and compressor components), industrial drying and food processing ovens, and in the electrical and electronics industries (e.g. high temperature insulators, and brush holders).
Manufactured of reinforced, internally lubricated linear polyphenylene sulphide resin, Techtron HPV PPS resists a wide variety of organic and inorganic chemicals.
Consequently, even after prolonged exposure and at elevated temperatures, the polymer exhibits little change in its mechanical properties.
Techtron HPV PPS' maximum allowable service temperature, based on thermal-oxidative degradation, is 260ºC for short periods and 220ºC for more than 20,000 hours of continuous use.
These values are well above those of most other thermoplastics and thermosets, says Dotmar EPP.
For example, the polymer's deflection temperature under a flexural load measured at a stress of 1.8N/mm is about 115ºC, 10ºC higher than that of virgin polyphenylene sulphide.
Dotmar EPP says the exceptionally durable Techtron HPV PPS demonstrates a superior resistance to creep and wear, which continues to be retained at temperatures up to 150ºC.
As a result, Techtron HPV PPS parts can sustain high static loads for long periods of time, even at temperatures above 100ºC, without showing deformation.
Dotmar EPP says Techtron HPV PPS' overall wear resistance and low coefficient of friction overcome the disadvantages of virgin polyphenylene sulphide, which has a rather poor wear resistance, and of glass fibre reinforced polyphenylene sulphide, which causes premature wear of the counterface in bearing applications.
Hence, where unlubricated moving parts are involved, Techtron HPV PPS' frictional properties result in a low heat build-up and high PV values.
Techtron HPV PPS preserves very good dimensional stability despite temperature variations, moisture absorption, stress relieving and chemical attack.
For instance, as an indication of the polymer's resistance to hydrolysis, no significant change in properties is detected even after long-term exposure to water at high temperatures.
Due to a special annealing process after production, Techtron HPV PPS stock shapes exhibit a favourable thermal expansion rate, a low level of internal stresses and a high degree of crystallinity.
This eliminates dimensional changes due to post-crystallisation when used at temperatures above 90ºC, a problem that often occurs with injection-moulded parts.
Additional key benefits include a high mechanical strength, stiffness, and hardness; good electrical insulating and dielectric properties (which are only marginally affected by changes in temperature, frequency or humidity); inherent low flammability; very good resistance against high energy radiation; and, moderate impact strength.
Part of the Quadrant EPP family of engineering plastics materials, Techtron HPV PPS is available in rods (10-100mm diameter), plates (10-50mm thick) and tubes (60-100mm OD).
All Quadrant EPP polymers are manufactured within the ISO 9002-certified quality system, and are available as engineered stock shapes through a network of authorised Dotmar EPP distribution centres in all States.