Liquid crystal polymer

Background

A number of LCP resins were produced in the 1970s which displayed order in the melt phase analogous to that exhibited by non-polymeric injection molded. Today, LCPs can be melt processed on conventional equipment at fast speeds with excellent replication of mold details.

A relatively unique class of partially crystalline aromatic polyesters based on p-hydroxybenzoic acid and related monomers. Liquid crystal polymers are capable of forming regions of highly ordered structure while in the liquid phase. However, the degree of order is somewhat less than that of a regular solid crystal. Typically LCPs have outstanding mechanical properties at high temperatures, excellent chemical resistance, inherent flame retardancy and good weatherability. Liquid crystal polymers come in a variety of forms from sinterable high temperature to injection moldable compounds.

LCPs are exceptionally inert. They resist stress cracking in the presence of most chemicals at elevated temperatures, including aromatic or sulfuric acid, and boiling caustic materials.

Typical LCP applications

• Electrical/Electronic Applications (characterized up to 110 GHz for circuit operation)
• Automotive Applications
• Parts, Engineering
• Containers, Food
• Appliances
• Industrial Applications
• Connectors
• Optical Applications
• Parts, Thin-walled

Advantages of LCP

• High Heat Resistance
• Flame Retardant
• Chemical Resistance
• Dimensional Stability
• Moldability
• Heat Aging Resistance
• Adhesion
• Low Viscosity
• Weldable
• Low Cost

Disadvantages of LCP

• Form weak weld lines
• Highly anisotropic properties
• Drying required before processing
• High Z-axis thermal expansion coefficient