New thermplastic vulcanizates (TPVs) with improved processability for injection molding applications
Harry Lardinoye, Jan Tom Fernhout, Yundong Wang, Hua Cai, and Ryszard Brzoskowski, DSM Thermoplastic Elastomers BV , The Netherlands
A new line of thermoplastic vulcanizates (TPVs) has been introduced by DSM Thermoplastic Elastomers for injection molding applications where UV resistance is critical. This new line of products, consisting of several grades with hardness ranging from 50 to 85 shore A in black color, shows superior flow characteristics and balanced properties meeting existing automotive material specifications. In this paper, we will discuss some of the features associated with this new line of products. After a short introduction on injection molding, specifically for TPVs, some basic properties of these new products are discussed, like crystallization behavior and cycle time. Most of these grades are formulated with the intention to increase their rate of crystallization over other commercially available TPVs. This ensures a faster solidification of the melt upon cooling, leading to a reduction in cycle time. A processing guideline gives information on the processing window of these new materials. Also some examples of typical applications in the automotive industry as glazing and sealing systems are included. As a conclusion: These high flow products are formulated to have low viscosity for ease of flow and better surface appearance. Through composition and process optimization, this product line is designed to offer excellent UV resistance, good fogging properties, and good mechanical and elastic properties with superior processability and consistency.