Product Information
Dec 2018
Ultradur® B 4520 PRO TR
Polybutylene Terephthalate (PBT)

Product Description
Ultradur B 4520 PRO TR is an unfilled injection molding PBT grade with special lubricant to minimize friction, stick-slip and squeaking, which supports customers in product development for the medical technology market. This grade complied with US Pharmacopoeia: Biological Reactivity Tests, USP Plastic Class VI (USP VI), ISO 10993-5: Biological Evaluation of Medical Devices Part 5: Test for Cytotoxicity, DMF: A Drug Master File (DMF) has been registered at FDA for Ultradur® PRO and Food Contact: Ultradur® PRO is in compliance with multiple regional food contact regulations, especially for Europe and United States.

PHYSICAL ISO Test Method Property Value
Density, g/cm³ 1183 1.30
Viscosity Number, cm³/g 1628 120
Mold Shrinkage, parallel, % 294-4 2.1
Mold Shrinkage, normal, % 294-4 2.3
Moisture, % 62  
    (50% RH) 0.25
    (Saturation) 0.5
RHEOLOGICAL ISO Test Method Property Value
Melt Volume Rate (250 C/2.16 Kg), cc/10min. 1133 20
MECHANICAL ISO Test Method Property Value
Tensile Modulus, MPa 527  
    23C 2,500
Tensile stress at yield, MPa 527  
    23C 50
Nominal strain at break, % 527  
    23C 28
Flexural Strength, MPa 178  
    23C 70
Flexural Modulus, MPa 178  
    23C 2,400
IMPACT ISO Test Method Property Value
Charpy Unnotched, kJ/m2 179  
   -30C 170
    23C 180
THERMAL ISO Test Method Property Value
Melting Point, C 3146 220
HDT A, C 75 58
HDT B, C 75 145
ELECTRICAL ISO Test Method Property Value
Comparative Tracking Index IEC 60112 600
Volume Resistivity (Ohm-m) IEC 60093 >1E16
Surface Resistivity (Ohm) IEC 60093 >5E16
Dielectric Constant (100 Hz) IEC 60250 3.3
Dielectric Constant (1 MHz) IEC 60250 3.1
Dissipation Factor (100 Hz), E-4 IEC 60250 21
Dissipation Factor (1 MHz), E-4 IEC 60250 200

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: