Product Information
Dec 2018
Ultradur® B 6550 LN
Polybutylene Terephthalate (PBT)

Product Description
Ultradur B 6550 LN is a high viscosity PBT extrusion grade.

Typical applications include semi-finished products, profile and hollow rods.

PHYSICAL ISO Test Method Property Value
Density, g/cm³ 1183 1.30
Viscosity Number, cm³/g 1628 160
Mold Shrinkage, parallel, % 294-4 1.9
Mold Shrinkage, normal, % 294-4 2.2
Moisture, % 62  
    (50% RH) 0.25
    (Saturation) 0.4
RHEOLOGICAL ISO Test Method Property Value
Melt Volume Rate (250 C/2.16 Kg), cc/10min. 1133 9.5
MECHANICAL ISO Test Method Property Value
Tensile Modulus, MPa 527  
    23C 2,600
Tensile stress at yield, MPa 527  
    23C 56
Tensile strain at yield, % 527  
    23C 3.5
Nominal strain at break, % 527  
    23C >50
Flexural Strength, MPa 178  
    23C 76
IMPACT ISO Test Method Property Value
Charpy Notched, kJ/m2 179  
    23C 6
Charpy Unnotched, kJ/m2 179  
   -30C 220
    23C N
THERMAL ISO Test Method Property Value
Melting Point, C 3146 223
HDT A, C 75 50
HDT B, C 75 135
ELECTRICAL ISO Test Method Property Value
Comparative Tracking Index IEC 60112 475
Volume Resistivity (Ohm-m) IEC 60093 5E13
Surface Resistivity (Ohm) IEC 60093 >1E15
Dielectric Constant (100 Hz) IEC 60250 3.4
Dielectric Constant (1 MHz) IEC 60250 3.2
Dissipation Factor (100 Hz), E-4 IEC 60250 19
Dissipation Factor (1 MHz), E-4 IEC 60250 219

Processing Guidelines
Material Handling
Max. Water content: 0.04%
To ensure optimum part performance, this product must be dried prior to molding and maintained at a moisture level of less than 0.04%. Dehumidifying or desiccant dryers operating at 100-120C (212-248F) at 4 hours drying time is recommended. Further information concerning safe handling procedures can be obtained from the Safety Data Sheet. Alternatively, please contact your BASF representative.

Typical Profile
Melt Temperature 230-290C (446-554F)

Temperature Settings (C):

Extruder 250/240/230C (482/464/446F)
Adaptor 225 deg C (437 def F)
Die 215 deg C (419 deg F)

Screw Parameters
Metering Section 45% 
Transition Section 3 to 4 flights 
Feed Section balance of screw length 
Compression Ratio 3:1 
L/D Ratio 20:1 

Tooling & Sizing
Die to Finished Tube dia. 2.0-2.5:1 Die Gap 3-4 times the desired wall thickness

The vacuum water calibration method is recommended when producing tube diameters 8 mm and below. Water termperature should be 20 deg C (68 deg F).

Although all statements and information in this publication are believed to be accurate and reliable, they are presented gratis and for guidance only, and risks and liability for results obtained by use of the products or application of the suggestions described are assumed by the user. NO WARRANTIES OF ANY KIND, EITHER EXPRESS OR IMPLIED, INCLUDING WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, ARE MADE REGARDING PRODUCTS DESCRIBED OR DESIGNS, DATA OR INFORMATION SET FORTH. Statements or suggestions concerning possible use of the products are made without representation or warranty that any such use is free of patent infringement and are not recommendations to infringe any patent. The user should not assume that toxicity data and safety measures are indicated or that other measures may not be required.

  BASF Corporation
Engineering Plastics
1609 Biddle Avenue
Wyandotte, MI 48192
General Information: 800-BC-RESIN
Technical Assistance: 800-527-TECH (734-324-5150)
Web address: