Delrin acetal enhances disposable insulin pen reliability and usability

This grade of Delrin, which complies with healthcare regulations, is used in two threaded components responsible for the dose accuracy of the system. The low friction nature of Delrin acetal homopolymer is credited for lowering the friction inside the pen mechanism and therefore reducing, for example, the injection force to be applied by the patient. The effective
impact strength of Delrin helps protect against breakage in case the pen is dropped.

The system was developed in close cooperation between the OEM, its consulting engineering firm, the moulder and DuPont’s application development experts. 

The high-flow rate of Delrin allows the use of highly productive multi-cavity hot runner moulds, resulting in cost-efficient and low-scrap manufacture of small
components down to 0.1g. In addition, Delrin also offers efficient dimensional stability.

Laurent Hanen, DuPont Performance Materials European segment leader – Medical, said the healthcare industry is a very demanding market driven by consumer needs and guided by regulations. As such, DuPont’s broad materials portfolio, design support and technical expertise can help customers to meet their most stringent requirements.


DuPont has proven and demonstrated its ability and expertise during the development and test phases of the two components. As a result, the customer was able to validate the part made of Delrin acetal homopolymer with full confidence of performance in use, reducing development lead time.

The DuPont healthcare product portfolio offers efficient structural properties and moulding characteristics
often facilitating the design and production of thinner and lighter parts. Several grades offer high flow rates to ease the moulding of geometrically complicated parts.

In addition, the portfolio requires minimal or no finishing operations, delivers rapid production cycles, and provides greater durability for longer life to help create cost savings. DuPont actively supports customers by assisting in material selection, tool design, and moulding optimisation.