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Besides the contact components the plastic materials are the critical building blocks for electromechanical components. Plastics used are mostly technical thermoplastics and heavy-duty plastics which fulfill the requirements for high mechanical strength, temperature stability, and fatigue strength ''(Table 10.1)''. For the final selection of a plastic material economical considerations and the avoidance of environmentally hazardous ingredients such as for example flame retardants must be considered. The application of the most suitable contact material coating and the selection of carrier materials are covered in chapters [[Contact Carrier Materials|Contact Carrier Materials]], [[Surface Coating Technologies| Surface Coating Technologies]] and [[Applications for Bonding Technologies|Applications for Bonding Technologies]].
<figtable id="tab:tab5.2">
'''Table 5.2: Composition of Some Pure Copper Types'''
{| class="twocolortable" style="text-align: left; font-size: 12px"
|-
!Type of Plastics:<br />Poly-condensate<br />Sub-Type: Thermo-<br />plastics Abbrev.
!colspan="6" style="text-align:center"| Properties
|-
!
!Density<br />[g/cm<sup>3</sup>]
!Reinforcement<br />Materials
!mechanical
!electrical
!thermal
!resistant against
|-
|'''PPS'''
|1.34 - 1.64
|glass fibers,<br />graphite fibers
|very high mechanical strength and<br />stiffness even at high temperatures,<br />low toughness, very low creep,<br />better properties with addition of<br />40% glass fibers
|excellent isolation<br />properties, very low<br />dielectric losses
|usable up to 240°C, short term<br />up to 270°C, low combustibility,<br />self-extinguishing, non-dripping
|up to 220°C no known solvents,<br />conc. sodium hydroxide,<br />conc. hydrochloric and sulfuric<br />acid, good hydrolysis resistance
|-
|'''PA6<br />PA66<br />PA610<br />PA11<br />PA12<br /> A amorph'''
|1.12 - 1.14<br />1.13 - 1.14<br />1.06 - 1.08<br />1.04<br />1.01 - 1.02<br />1.06 - 1.12
|glass fibers,<br />graphite fibers,<br />mineral powders,<br />glass beads, chalk,<br />lubricants such as<br />graphite, MoS<sub>2</sub>
|depending on the PA type, crystalline<br />structure and water content; high<br />mechanical strength, stiffness, and<br />toughness; higher mech. strength<br />through stretching; very tough after<br />water absorption; high fatigue strength,<br />good impact toughness, abrasion<br />resistant, good sliding properties<br />through addition of graphite and MoS<sub>2</sub>;<br />increased mechanical strength with<br />glass and graphite fiber addition
|depending on water<br />content, good surface<br />resistance reduces static<br />surface charge, high<br />dielectric losses, good<br />resistance against creep<br />currents
|upper use temperature 80 – 120°C<br />depending on type, short term<br />up to 140 – 200°C, mostly<br />boil resistant, can be sterilized,<br />narrow softening range
|aliphatic and aromatic<br />hydrocarbons, gasoline, oils,<br />greases, some alcohols, esters,<br />ketenes, ether,<br />many chlorinated hydrocarbons, <br />weak alkaline solutions
|}
</figtable>
== Hybrid Frames and Housings==
