Material guide
PPS, polyphenylene sulfide
PPS, polyphenylene sulfide. A high temperature plastic that combines good heat resistance with unusually good chemical resistance and high dimensional stability. The technical workhorse when things are both hot and chemically tough.
What it is
PPS, polyphenylene sulfide, is a semi-crystalline high temperature plastic that handles both heat and chemicals better than most. It keeps its strength and stiffness at high temperatures, takes up almost no moisture and stands up to a wide span of chemicals, including ones that attack many other plastics. Add high dimensional stability and inherent flame resistance, and you have a material that often ends up in pump, valve and process parts. PPS sits in the premium segment, below PEEK but a good way above everyday engineering plastics. It is almost always supplied in a filled version, more about that under grades. Note the difference from PPs with a lowercase s, which is an entirely different material, flame retardant polypropylene. PPS with a capital S is polyphenylene sulfide and considerably more expensive.
Properties
High continuous heat resistance, keeps its shape where ordinary plastics soften
Unusually good chemical resistance, even against media that attack many other plastics
High dimensional stability, the dimensions move little with temperature and moisture
Takes up almost no moisture
Inherently flame resistant without additives
Typically supplied glass fiber filled for high stiffness and strength
Common applications
PPS sits where heat and chemicals meet. Typical parts are pump housings, valve components, sealing components and impellers in process and chemical engineering, plus parts in vehicles under the hood where it is hot and exposed. It is also used for components in electrical engineering and electronics thanks to its dimensional stability and flame resistance. When a designer needs a material that stands up to both high temperatures and an aggressive liquid, but does not want to go all the way to PEEK, PPS is often the answer.
Limitations
PPS in a filled version is stiff but can be more brittle than tougher plastics, so it is not the first choice where high impact strength is required; a tough engineering plastic or PPSU suits better there. It is a premium material in price, so it is chosen for heat and chemicals, not as a cheap all round plastic. For the very highest temperature requirements, PEEK or PAI sit above PPS. If your part needs to be tough rather than stiff, or cheap rather than chemically resistant, there are better choices in the range.
Our PPS grades go down to -20 °C, and upward they lie between 220 and 230 °C depending on grade.
Grades and variants
PPS is almost always supplied in a filled version, because the pure plastic is brittle. Which grade suits is governed by whether the part is primarily to be stiff, dimensionally stable or wear resistant.
Base grades
- PPS glass fiber filled, the most common grade, for high stiffness, strength and dimensional stability in heat.
- PPS with combined fillers, for example glass and mineral, for balanced mechanical properties and dimensional stability.
If you are unsure, we will help you choose the right grade.
Machining
PPS is sawn, milled, drilled and turned. In a filled version the material becomes stiff and hard, but also more brittle, so be careful with impacts and hard clamping.
Formats we can supply
PPS is available as sheets, round rods, tubes and hollow bars, as well as welding rod and Twin-Wall for welded constructions. You see formats and dimensions in the range. Would you like a piece cut to size? Enter the dimensions in VisualCutter and you will see the price straight away.