Molecularly Oriented Polymers as Heat Spreaders

Applications

Oriented polymers can be used as heat exchangers for applications ranging from small electronic enclosures to large industrial heaters.

Problem Addressed

Ultra-high molecular weight polyethylene (UHMWPE) is used in a variety of industrial applications ranging from bullet proof vests to high strength ropes because of its strong mechanical properties. However, UHMWPE is limited in its applications because the bulk material has low thermal conductivity. This technology improves the thermal conductivity of UHMWPE by stretching the polymer chains to create a shish-kebab structure. Additionally, UHMWPE is much cheaper to produce than traditional thermal conductors such as metals.

Technology

There are several methods for stretching polymer strains; the one used for this technology involves stretching the bulk polymer around a shaft that is submerged in oil to ensure thermal uniformity. After stretching, the thermal conductivity is as high as ~104 W m-1 K-1, which is greater than many of the pure metals. Additionally, the thermal conductivity is anisotropic and is higher in the direction that the material is stretched.

Advantages

  • Increases thermal conductivity in polymers
  • Cheaper than traditional thermal conductors