General Purpose Resins
A large combination of base polymers and fillers can be used for thermoplastic encapsulation. We generally favor semi-crystalline resins due to the better melt flow and superior chemical resistance. Encap can direct you to the optimum resin for a specific application, however the information below helps to give a basic idea of some of the resins often used for encapsulation.

Resin Descriptions
Talc Filled Polypropylene (PP) – A good resin for a broad range of applications, where low cost is critical and structural and ambient temperature requirements are low to intermediate. Polypropylene has excellent chemical resistance and is found in many under-the-hood automotive applications.

Nylon (Polyamide) – Nylon has a strong combination of properties, particularly toughness, chemical resistance, and strength. It is found in under-the-hood automotive applications requiring higher thermal and mechanical properties than polypropylene.

Glass Reinforced PBT – Like nylon, PBT is a semi-crystalline resin exhibiting a good combination of properties. Relative to nylon, PBT would have advantages of additional dimensional stability and electrical properties, but with lower toughness.

Glass Reinforced PPS – PPS is known for its high levels of stiffness, creep resistance, and for a high operating temperature. It finds wide usage in industries such as the hard disk drive industry where low outgassing is required. Toughness is generally lower, though this is often not a factor with the design of encapsulated components.

Liquid Crystal Polymer (LCP) – LCP is used in a wide range of encapsulated applications. Most applications are in the electrical industry due to LCP’s advantages in temperature, stiffness, dimensional stability, and the ability to fill thin wall sections.