Chemical Manufacturing &
The chemical manufacturing and processing industries require materials with resistance to severe environments, corrosive solvents, abrasive processes and extreme conditions every day. A wide variety of plastic materials are available to meet the needs of these businesses. High temperatures and pressures, high or low pH solutions, rugged use, chemical attack, and extreme wear are just some of the issues that must be considered in such situations. Pressure vessels, processing tanks, holding reservoirs, transfer pipes, reaction basins, pump and valve components must all be able to survive breakdown to avoid improper operation and safety hazards.
The paragraphs below describe specific materials and their uses in this industry . . .
See our table showing Agency Approvals and Listings for many plastic materials.
- PEEK (PolyEtherEtherKetone)
PEEK offers exceptional chemical resistance combined with heat resistance to 480°F. It does not degrade with exposure to water or steam, and is flame- and radiation-resistant. Because of these properties, PEEK can withstand the chemical and mechanical stresses present during sterilization and chemical cleaning. This material is available in sheet, rod and tube forms. NOTE: Boedeker Plastics now carries Virgin PEEK 450G Tube Stock.
- PTFE (PolyTetraFluoroEthylene)
PTFE offers high chemical resistance, resistance to most chemicals (including strong acids and bases), low friction, electrical and thermal insulation, and "slipperiness". It's useful temperature range is very wide; from -100°F to +400°F (-73°C to 204°C). Unfilled PTFE lacks mechanical strength in some configurations, so it is typically used for seals, gaskets, fittings, and non-loaded parts. A wide variety of filled grades are also available which offer improved or enhanced mechanical properties while maintaining many of PTFE's advantages.
- FEP (TetraFluorEthylene-Perfluorpropylene)
TetraFluorEthylene-Perfluorpropylene (FEP) is a relatively soft thermoplastic with lower tensile strength, wear resistance, and creep resistance than many other engineering plastics. However, it is chemically inert and a very high degree of stress crack resistance, a low coefficient of friction, heat resistance, and retention of properties after service at +400°F (204°C) with useful properties at -454°F (-270°C), and meets FDA 21CFR.177.1550. FEP has high transparency (with good transmittance of UltraViolet and visible wavelengths.) It has long term weatherability and excellent resistance to ozone, sunlight and weather. Important applications are linings for pipe and chemical processing equipment, roll covers, and numerous wire and cable applications, including fire alarm cable, and well logging cable. Heat-shrinkable FEP tubing is available. FEP Film is used as glazing in solar energy collectors.
- PFA (PerFluoroAlkoxy)
PerFluoroAlkoxy (PFA) offers similar properties to FEP, but is considered more of a premium resin. PFA is preferred when extended service is required in hostile environments involving chemical, thermal, and mechanical stress. PFA offers high melt strength, stability at high processing temperatures, excellent crack and stress resistance, a low coefficient of friction, and more than 10 times the Flex life of FEP. PFA has high resistance to creep and retention of properties after service at 500°F (260°C), with useful properties at -320°F (95°C). PFA also meets FDA 21CFR.177.1550. PFA is used in the same types of applications as those listed above for FEP.
- Tefzel® ETFE (Ethylene-TetraFluoro-Ethylene)
ETFE is free of fillers, lubricants or plasticizers and will not leach or contaminate. It is virtually unaffected by most chemicals, and has a continuous-use temperature range of -148°F to +311°F. ETFE is extremely durable with nylon-like abrasion characteristics. This material may be welded using special materials and conditions for use in chemical applications where the above properties are critical.
- Kynar® PVDF (PolyVinyliDene Fluoride)
PVDF is ultrapure, resistant to most chemicals, mechanically tough and abrasion resistant. In addition, PVDF fabric-backed sheet is ideal for lining chemical tanks and trailers, including those used in high purity DI water systems.
- Halar® ECTFE (Ethylene-ChloroTriFluoro-Ethylene)
Parts made from ECTFE are resistant to strong alkalines, acids, and temperatures up to 300°F. It is also microsmooth and resists both bacterial adhesion and particulate generation. ECTFE may be welded, bonded, machined and thermoformed.
- Cast Nylon (Polyamide or PAI)
Nylon is one of the most widely used plastics in the world, especially as a bearing and wear material. Nylons are frequently used as replacements for bronze, brass, aluminum, steel and other metals, as well as other plastics, wood, and rubber. Nylons offer extremely good wear resistance, coupled with high tensile strength and stiffness. They also have high impact resistance, a high heat distortion temperature, and resist wear, abrasion, and vibration. In addition, nylons can withstand sustained contact with a wide variety of chemicals, alkalies, dilute acids or oxidizing agents. Nylon is commonly used for gears, sheaves, sprockets, wheels, wear pads, slide pads, washers and bearings.
- Acetal Copolymer (PolyOxy-Methylene or POM)
Acetal Copolymer is a well-recognized engineering thermoplastic which is widely used in many medical applications. Acetals may be steam autoclaved, are easily machined, and are available in seven lot-controlled FDA-compliant colors. Acetals are an excellent choice for color coded provisional trials. Acetals are also USP Class VI compliant.
- Ertalyte® PET-P (Polyethylene Terephthalate)
Ertalyte® offers the dimensional stability of acetal with the wear resistance of nylon. Because of its excellent resistance to water and a broad range of pH (2.0 to 9.0), Ertalyte® can be used in wet environments without staining or weakening its mechanical properties.
- PVC (PolyVinyl Chloride) & CPVC (Chlorinated PolyVinyl Chloride)
PVC is the most widely used member of the vinyl family. It is most commonly used in pipe and fittings. PVC offers excellent corrosion and weather resistance. It has a high strength-to-weight ratio and is a good electrical and thermal insulator. PVC is also self-extinguishing per UL flammability tests. PVC may be used to temperatures of 140°F (60°C) CPVC shares most of the features and properties of its close relative, PVC. It is also readily workable, including machining, welding, and forming. Because of its excellent corrosion resistance at elevated temperatures, CPVC is ideally suited for self-supporting constructions where temperatures up to 200°F (93°C) are present. The ability to bend, shape, and weld CPVC enables its use in a wide variety of process applications including tanks, scrubbers, and ventilation systems. It exhibits excellent fire and chemical resistance. Both PVC and CPVC are readily available in sheets, rods, and tubing.
- PolyPro (Polypropylene)
Polypropylene is an economical material that offers a combination of outstanding physical, chemical, mechanical, thermal and electrical properties not found in any other thermoplastic. Compared to low or high density polyethylene, it has a lower impact strength, but superior working temperature and tensile strength. Polypropylene provides excellent resistance to organic solvents, degreasing agents and electrolytic attack. It has a lower impact strength, but its working temperatures and tensile strength are superior to low or high density polyethylene. It is light in weight, resistant to staining, and has a low moisture absorption rate. This is a tough, heat-resistant, semi-rigid material, ideal for the transfer of hot liquids or gases. It is recommended for vacuum systems and where higher heats and pressures are encountered. It has excellent resistance to acids and alkalines, but poor resistance to aromatic, aliphatic and chlorinated solvents.
- Polyethylene (LDPE, HDPE, and UHMW-PE)
Polyethylenes are semi-crystalline materials with excellent chemical resistance, good fatigue and wear resistance, and a wide range of properties (due to differences in length of the polymer chain.) Polyethylenes are easy to distinguish from other plastics because they float in water. Polyethylenes provide good resistance to organic solvents, degreasing agents and electrolytic attack. They have a higher impact strength, but lower working temperatures and tensile strengths than polypropylene. They are light in weight, resistant to staining, and have low moisture absorption rates. See the datasheet for the differing properties of Low Density (LDPE), High Density (HDPE) and Ultra High Molecular Weight Polyethylene (UHMW) grades.