Product Information
Jul 2020
Ultradur® B 4406
Polybutylene Terephthalate (PBT)

Product Description
Ultradur B 4406 is an injection molding PBT grade grade with migration-free flame retardant offering a UL V0 rating.

Typical applications include relay housings, plug-in connectors, and switch and lamp parts.

PHYSICAL ISO Test Method Property Value
Density, g/cm³ 1183 1.45
Viscosity Number, cm³/g 1628 122
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 30
MECHANICAL ISO Test Method Property Value
Tensile Modulus, MPa 527  
    23C 3,000
Tensile stress at yield, MPa 527  
    23C 65
Tensile stress at break, MPa 527  
Tensile strain at yield, % 527  
    23C 3.9
Nominal strain at break, % 527  
    -40C 3.3
    23C 3.5
Tensile Creep Modulus (1h), MPa 899 1,800
IMPACT ISO Test Method Property Value
Charpy Notched, kJ/m2 179  
    -30C 4
    23C 4
Charpy Unnotched, kJ/m2 179  
    23C 50
THERMAL ISO Test Method Property Value
Melting Point, C 3146 223
HDT A, C 75 60
HDT B, C 75 170
Coef. of Linear Thermal Expansion, Parallel, mm/mm C 0.55 X10-4
ELECTRICAL ISO Test Method Property Value
Comparative Tracking Index IEC 60112 250
Volume Resistivity (Ohm-m) IEC 60093 >1E13
Surface Resistivity (Ohm) IEC 60093 1E13
Dielectric Constant (100 Hz) IEC 60250 3.3
Dielectric Constant (1 MHz) IEC 60250 3.3
Dissipation Factor (100 Hz), E-4 IEC 60250 110
Dissipation Factor (1 MHz), E-4 IEC 60250 170
UL RATINGS UL Test Method Property Value
Flammability Rating, 0.4mm UL94 V-0
Flammability Rating, 0.75mm UL94 V-0
Relative Temperature Index, 0.75mm UL746B  
    Mechanical w/o Impact, C 140
    Mechanical w/ Impact, C 130
    Electrical, C 125
Flammability Rating, 1.5mm UL94 V-0
Relative Temperature Index, 1.5mm UL746B  
    Mechanical w/o Impact, C 140
    Mechanical w/ Impact, C 130
    Electrical, C 125
Flammability Rating, 3.0mm UL94 V-0
Relative Temperature Index, 3.0mm UL746B  
    Mechanical w/o Impact, C 140
    Mechanical w/ Impact, C 130
    Electrical, C 125

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 250-270C (482-518F)
Mold Temperature 40-80C (104-176F)
Injection and Packing Pressure 35-125 bar (500-1500 psi)

Mold Temperatures
This product can be processed over mold temperatures of 40-80C (104-176F), although 80C (176 deg F) will result the best surface.

Injection pressure controls the filling of the part and should be applied for 90% of ram travel. Packing pressure affects the final part and can be used effectively in controlling sink marks and shrinkage. It should be applied and maintained until the gate area is completely frozen off.

Back pressure can be utilized to provide uniform melt consistency and reduce trapped air and gas. A maximum of 10 bar (145 psi) is recommended due to the risk of excessive shear.

Fill Rate
Fast fill rates are recommended to ensure uniform melt delivery to the cavity and prevent premature freezing. Surface appearance is directly affected by injection rate.

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: