High Performance Polymers

Fluorosilicone (FVMQ)

Description

Fluorosilicone combines most of the attributes of silicone with resistance to petroleum oils and hydrocarbon fuels. Low physical strength and abrasion resistance combined with high friction limit fluorosilicone to static seals.

Advantages:

  • Temperature range of -72 °C to 200 °C Excellent resistance to ozone, sunlight and oxidation.
  • Excellent electrical resistivity. Excellent flame resistance.
  • Excellent resistance to water, ammonia, dilute.

Limitations:

  • Poor mechanical properties rating. Low tensile strength.
  • Fair compression set resistance.
  • Poor resistance to ketones and oxygenated solvents.

Usage:

Aeronautical seals, highly specialized and extreme low temperature seals.

Perfluoroelastomer (FFKM)

Description

Perfluoroelastomers show ultimate performance among all elastomers. They are resistant to nearly every chemical class with some grades offering heat resistance to over 300 C. This makes FFKM the material of choice of high demanding sealing applications .Ismat’s specialty compounds deliver an extreme performance range that make them suitable for use in critical applications like semi-conductor chip manufacturing, jet engines, chemical processing equipment and Oil & Gas which require a wide range of extreme performance.

Advantages:

  • Excellent heat resistance.
  • Resistant to almost every chemical class.
  • Excellent outgassing performance in vacuum environments.
  • Wide temperature range of 30 °C to 300 °C

Limitations:

  • Avoid low molecular weight, fully halogenated fluids and molten alkali metals.
  • Strong oxidizing acids may cause some swelling.
  • Helium permeability is slightly higher than fluoroelaster  compounds.

Usage

All areas where extreme critical application is required.

Polyetheretherketone (PEEK)

Description

PEEK (polyetheretherketone) is one of the industry’s most chemically resistant plastics and offers excellent strength, superior fatigue resistance, and a continuous-use temperature of 240 C (460 F). Graphite reinforced and carbon fiber-reinforced grades provides a wide range of performance options for demanding applications.

Advantages:

  • High compressive strength
  • PEEK is compatible with ultra-high vacuum applications.
  • Lightweight, very strong and extremely high chemical resistance. Highly wear resistant and resistant to stress cracking

Limitations:

  • It is attacked by halogens and strong Bronsted and lewis acids as well as some halogenated compounds and aliphatic hydrocarbons at high temperatures.
  • It dissolves completely in concentrated sulphuric acid at room temperatures.

Usage

PEEK is used to fabricate items used in applications like bearings, piston parts, pumps, valve seats.

Polychlorotrifluoroethylene (PCTFE)

Description

PCTFE is a white translucent material which is very rigid. It has excellent resistance to cold flow, exhibits dimensional stability at a wide temperature range, has a very low gas permeability and low moisture absorption properties. PCTFE is also FDA approved.

Advantages:

  • Stress- crack resistance.
  • High mechanical strength and low shrinkage rate at low temperature provide excellent stability for valve seats.
  • Excellent chemical resistance. Practically zero moisture absorption.

Limitations:

  • PCTFE swells slightly in halocarbon compounds, ethers, esters and aromatic solvents.
  • Although PCTFE has excellent chemical resistance, it is still less than that of PTFE.

Usage:

  • Cryogenic valve seats.
  • High pressure gas seats and seals. Semi-conductor process components such as wafer boats.
  • Sight glasses and windows. Electrical components.
  • Parts for high vacuum applications.

Modified Polytetrafluoroethylene (TFM)

Description

TFM is a chemically modified version of PTFE that has improved capabilities over Virgin PTFE. Some of the advantages include reduced cold flow, much lesser deformation under load, smoother surface and better flexibility.

Advantages:

  • Past surfaces are smoother, and less porous components stay clean since they are less likely to trap contaminants.
  • Low micro-vivid content yields improved permeable resistance.
  • Longer flex life than PTFE
  • Increased stiffness and improved creep resistance.

Limitations:

  • High Cost.
  • Not recommended for very high pressure applications.

Usage:

Gaskets, Seals, Ball Valve Seals, etc.