PDF《Overview》

Overview DuPont? Delrin? acetal homopolymer resin - also called Delrin? POM-H - is one of the most crystalline engineering thermoplastics available.

Delrin? is a highly adaptable material that bridges the gap between plastics and metals and offers unique properties. It is specified for high load mechanical applications and precision parts, where strength, stiffness, stability and reliability are important. Applications range from gears, safety restraint components, door system and conveyor systems components to medical delivery devices, ski bindings, zip fasteners and many other applications across a wide range of products and industries. When compared to acetal copolymers, Delrin? homopolymer combines higher fatigue and creep resistance with overall higher toughness and higher tensile strength and stiffness, allowing for thinner and lighter part design, and the potential for reduced part production cost. This white paper describes the differences between Delrin? homopolymer and acetal copolymer in detail and explains how to make the best use of the higher level of mechanical performance of Delrin? homopolymer over that of acetal copolymer in order to extract the most value for all stakeholders. Table of contents 1. Introduction 2. What is an acetal polymer 3. Key properties of Delrin? acetal homopolymer 4. Mechanical properties comparison in detail 5. When to use Delrin? acetal homopolymer 6. Customer benefits of mechanical properties 7. How to exploit the superior mechanical properties of Delrin? acetal homopolymer vs. acetal copolymer 8. Case Study 9. How all stakeholders can benefit 10. Conclusion White paper - DuPont? Delrin ? acetal homopolymer C Page

2 1. Introduction The need for reduced energy consumption and cost through metal-replacement with lightweight engineering polymers is a confirmed trend in the automotive industry, and is increasingly gaining ground in general engineering and many other industry sectors. Acetal polymer already plays a major role in the advanced materials revolution. It is being used in a broad range of applications in the automotive, food processing, life sciences, safety and manufacturing industries, to name but a few. There are different kinds of acetals with different levels of performance. Suppliers of acetals often offer equivalent grades of copolymer as a substitute for a certain grade of homopolymer, and it is not always clear why one would use acetal homopolymer over acetal copolymer, or vice versa. However, it would be a mistake to think that all acetal resins are the same. As the plastics industry has evolved, so have the needs of the stakeholders concerned: ? The design engineer wants the best possible properties to maintain a good safety factor while pursuing an efficiently-designed lightweight part, and may require design validation support. ? The molding operator wants the highest resin flow rates. ? The procurement manager wants the lowest raw material price, consistent quality, and, ideally, multi-location production of raw materials. ? The plant manager wants a high production rate and the ability to ramp up production without capital investment. ? The process engineer wants technical support during production startup and for continuous improvement efforts. ? The customer generally wants to create durable, reliable, high-quality parts that deliver on promise and minimize the risk of costly recalls. The material selection process must counterbalance the needs of all these stakeholders. 2. What is an acetal polymer? Acetal, also called polyoxymethylene (POM), was first discovered in 1920, but was not produced on a large scale until DuPont opened the world'