Chapter 9 - Other Polymers: Styrenics, Silicones, Thermoplastic Elastomers, Biopolymers, and Thermosets

Abstract

Commodity plastics like polyvinyl chloride (PVC), polyethylene, polypropylene, and polystyrene make up over 70% of the share of plastics used in medical devices. Engineering thermoplastics are used in applications that require better strength, stiffness, toughness, chemical resistance, and biocompatibility compared to commodity resins. High-temperature engineering thermoplastics have very high temperature resistance, strength, biocompatibility, and durability. Many implant applications use these materials. Other types of polymers have also been developed to improve the ergonomics and aesthetics of surgical instruments, to be used as alternatives for DEHP-free PVC, to be reabsorbed into the body, and to be used as adhesives for bonding and assembly. This chapter focuses on styrenics, thermoplastic elastomers, biopolymers, and thermosets that meet some of these other needs. Several copolymers and copolymer blends of polystyrene, known as styrenics, have been developed to improve properties like heat resistance, chemical resistance, and toughness and impact properties that are deficient in polystyrene. Thermoplastic elastomers bridge the gap between thermoplastic polymers and thermosetting elastomers. These materials can be thermally processed via the same methods as thermoplastics but have rubber-like properties of elasticity, toughness, and impact resistance.