How to Select Polymers and Plastic Materials
Polymers and plastic materials are high molecular weight compounds comprised of two or more repeating organic or synthetic base molecules.
Types of Polymers and Plastic Materials
The GlobalSpec SpecSearch Database contains these types of polymer and plastic materials.
- Thermoplastics are polymers that turn to liquid when heated and turn solid when cooled. They can be repeatedly remelted and remolded, allowing parts and scraps to be reprocessed. In most cases they are also very recyclable.
- Elastomers and rubber materials are characterized by their high degree of flexibility and elasticity (high reversible elongation). They are based on a variety of different systems, including silicone, polyurethane, chloroprene, butyl, polybutadiene, neoprene, natural rubber or isoprene, and other synthetic rubber or compounds.
- Thermosets or thermosetting plastics are polymer materials that have been irreversibly cured. They are generally stronger than thermoplastics due to polymer cross-linking and are better suited for high-temperature applications (below their decomposition points). They tend to be more brittle than thermoplastics and many cannot be recycled due to irreversibility.
Polymer and Plastic Material Properties
Special consideration should be given to properties such use temperature, coefficient of thermal expansion, thermal conductivity, and tensile strength. Use temperature is the allowable temperature range in which the compound can operate effectively which determines what environments the resin can be used in. The coefficient of thermal expansion is a measure of the tendency of the compound to change in volume in response to temperature, which could limit space restraints under certain operating temperatures.
The thermal conductivity of the polymer is a measure of how well the material conducts heat or transfers heat, which is important for temperature conscious environments. Tensile strength is the maximum stress a material can withstand while being stretched or pulled before necking deformation occurs.
Material Types and Grades
Material types for polymers and plastic materials include cross-linked materials and resins, and compounded raw materials such as pellets and liquids. Electrical and electronic materials, optical grade materials, and self-lubricated or bearing-grade plastics and plastic materials are also available.
Cure Type and Components
Cure type or cure technology is also an important consideration when selecting products. Choices include air setting or film drying, anaerobic, thermoplastic or hot melt, thermosetting or cross-linking, room-temperature curing or vulcanizing, and pressure sensitive adhesive (PSA). Polymers and plastic materials that are cured with ultraviolet light (UV) are also available, as are reactive resins, single-component products, and two-component systems.
Related Products & Services
Conductive compounds provide an electrically and/or thermally conductive path between components.
Conformal coatings encapsulate circuit boards and their electronic components in order to prevent the ingress of moisture, fungus, dust and other environmental contaminants.
Epoxy adhesives are chemical compounds for joining components. They require clean surfaces and are valued for their toughness and resistance to chemical and environmental damage.
Gel elastomers are highly viscoelastic polymer gel materials that have excellent shock absorption and damping characteristics. They are available in a variety of material types and grades.
Pressure Sensitive Adhesives (PSA) and Contact Adhesives
Pressure sensitive adhesives (PSA) and contact adhesives adhere to most surfaces with very slight pressure. They are available in solvent and latex or water-based forms.
Silicone Adhesives and Sealants
Silicone adhesives and sealants have a high degree of flexibility and a very high temperature resistance (up to 600° F), but lack the strength of other epoxy or acrylic resins.
Thermoplastics and Thermoplastic Materials
Thermoplastics and thermoplastic materials soften when heated and harden when cooled. They can withstand many heating and cooling cycles and are often suitable for recycling.
- Aramid Fiber
- Building / Construction
- Carbon / Graphite
- Casting Resin
- Composite Structures
- EMI / RFI Shielding
- Elastomer / Rubber
- Electric Power
- Electrically Conductive Compound
- Energy Conversion (Battery/Fuel Cell/PV)
- Ethylene Copolymer (EEA, EVA)
- Extrusion Grade Resin
- Fiber Glass
- Film Grade Resin
- Flame Retardant (e.g. UL 94 Rated)
- Fluoropolymer (PTFE / PVDF)
- Medical / Food (FDA)
- Military / Government (MIL-SPEC)
- Molding Resin
- Optical Grade
- Filler Material:Other
- Phenolics (Melamine, Furan)
- PolyVinyl Chloride (PVC)
- Polyamide / Nylon
- Polyamide-imide (PAI)
- Polycarbonate (PC)
- Polyester (PET, PBT)
- Polypropylene (PP)
- Semiconductor / IC's
- Specialty / Other
- Styrene Copolymer (SIS / SBS)
- Thermally Conductive
- Thermally Insulating
- Tooling / Molds
- UL Approved
- Vinyl Ester