Related Information

Before measuring PA66 samples with the VM-E01, you may also want to know:

Common Questions About PA66 and Plastics

WKT-A9 Karl Fischer Trace Moisture Analyzer Coulometric

Reference Value Determination

The PA66 reference moisture value was determined with the VicoMeter WKT-A9 Karl Fischer moisture analyzer and WKT-V2 Karl Fischer oven; released moisture is carried by dry nitrogen into the electrolytic cell.

Recommended Settings for Plastics Industry Samples

If you have no reference method for plastics samples on the VM-E01, VicoMeter recommends these settings from experimental experience:

• Heating mode: Standard

• Shutoff mode: Automatic (1 mg/140 s)

• Sample size: 30 g

• Resolution: High (0.1 mg/0.0001 g)

• Warm-up: standby, 100°C; at standby temperature, preheat the empty pan for 1 minute, then tare.

Selecting the Drying Temperature

Figure 1: Same Sample Heated at Different Temperatures

(Click image to enlarge)

Choose a drying temperature matching the Karl Fischer reference value. Melting or marked color change means the temperature is too high. Some samples inevitably discolor when heated (polyamide unavoidably turns brown).

Figure 1 compares samples after two heating runs. Left: correct temperature — no melting or discoloration. Right: the sample browned, so the temperature was too high.

Plastic Sample Handling

Measure samples promptly. Otherwise, fill the container completely (use a smaller one if needed) and seal it to minimize air and prevent moisture uptake during storage.

Operating Steps for PA66 (Nylon 66, Polyamide 66) Samples

Place the VM-E01 in a suitable spot, warm up 30 min, level it (bubble centered), and perform weighing and temperature calibration. Then measure PA66 samples (installation, environment, warm-up, calibration: seePreparation Before Formal Measurement with a Halogen Moisture Analyzeras discussed in that article; click the link to learn more.).

Tare Sample Pan

1. Power on, warm up 30 min. Place the empty pan on the center holder, preheat 1 min at 160°C standby, press tare to zero.

Add Sample

2. Quickly spread about 30 g of PA66 sample evenly on the pan; wait for a stable reading.

One-Touch Start

3. Press start; the PA66 moisture result appears within minutes.

Test Data

VM-E01 Halogen Moisture Analyzer（0.1mg/0.0001g）

VM-E01 Settings Reference

• Heating mode: Standard

• Heating temperature: 160°C

• Shutoff mode: Automatic (1 mg/140 s)

• Sample size: 30 g

• Resolution: High (0.1 mg/0.0001 g)

• Warm-up: standby, 100°C; at standby temperature, preheat the empty pan for 1 minute, then tare.

Sample Information

• Sample Description: PA6.6-GF30, beige, 30% glass-fiber reinforced, good thermal stability, hydrolysis-resistant.

• Typical Maximum Allowable Moisture Content [%]: 0.02

• Hygroscopicity (23°C/50% rH) [%]: 1.9

Moisture Chart for PA66 Samples Before and After Drying

Chart Notes

Moisture Data for PA66 Samples Before and After Drying

Sample-Specific Test Notes

Maximum allowable moisture for pellet processing must always follow supplier specifications. Values here are typical only and may not suit your material or process.

These drying parameters were obtained on common plastics and do not cover all grades or colors; optimizing them may be needed for best results on a specific material.

Dr. Wei's Classroom

PA66 has a relatively high melting point among polyamides. A semi-crystalline to crystalline material, it keeps high strength and stiffness at elevated temperatures and stays hygroscopic after molding (depending on composition, wall thickness, environment) — its effect on dimensional stability must be considered in design. Modifiers improve mechanical properties: glass fiber is most common; synthetic rubber adds impact resistance. Low viscosity gives very good flow (below PA6), suiting thin parts; viscosity is very temperature-sensitive. Shrinkage 1%–2%, reducible to 0.2%–1% with glass fiber, differing markedly with flow direction. Melting point: distinct for this crystalline polymer, 259–267°C by test method (typically 264°C by DTA; 246–263°C by volumetric expansion, near the theoretical 259°C). Molding — drying: sealed material needs none; once opened, dry in 85°C hot air; if moisture > 0.2%, vacuum dry at 105°C for 12 h.