High-performance polymers (PSU, PEI, PEEK, PPS, LCP)

LCP (Liquid Crystal Polymer)

Very high temperature, chemical and mechanical performance. Expensive; narrow processing window.

Processing temperatures

Melt (injection) temperature	335 °C
Mold surface temperature	90 °C
Ejection temperature	155 °C

Typical values. They vary (±) with grade and manufacturer; see the data sheet.

Physical properties (typical)

Density	1.4 g/cm³
Shrinkage (flow / cross)	0.1 / 0.5 %
Specific heat	1.2 kJ/kg·K
Thermal conductivity	0.32 W/m·K
Latent heat of crystallization (approx.)	10 kJ/kg

Drying

Drying is required (follow the data sheet).

For exact conditions see the material data sheet. Drying guide →

Points to watch

High melt and mold temperature; mold heating (oil/electric)
High pressure and abrasive fillers; mold and screw material
Gas and degradation; venting and cleaning

Typical use: Aerospace, medical, electronics, chemical industry

Defects common with this material

Splay (silver streaks)

Fine silvery streaks on the part surface in the flow direction.

splay · silver streaks · moisture streaks

Brittleness / low impact strength

The part breaks more easily than expected; sometimes the surface looks fine.

brittleness · brittle part · cracking

Warpage

The part distorts or bends after it leaves the mold.

warpage · distortion · bowing

Sink mark

A dent on the surface opposite a thick section; the surface is drawn inwards.

sink mark · depression · sink

Dimensional variation and shrinkage differences

Part dimensions fall outside the tolerance or vary from cycle to cycle.

dimensional error · shrinkage · out of tolerance

Short shot (incomplete fill)

The cavity does not fill completely; the farthest or thinnest area of the part stays incomplete.

incomplete fill · underfill · non-fill

Other grades in the same family

Do the values for this material not match your grade? and we will correct them.