每年生产600多万吨,热塑性弹性体(TPE)在现代社会已经无处不在,由于它们独特的弹性组合,韧性,和可再加工性。然而,工业TPE显示出柔软度和强度之间的权衡,随着较低的高工作温度,一般≤100℃这限制了它们的效用,例如在生物界面应用中,需要超软变形与强度相结合,除了需要热稳定性的应用(例如,电子封装,航空用密封件/接头,消防防护服,和可以进行蒸汽灭菌的生物医学设备)。因此,结合柔软性,力量,和高热阻到一个单一的多功能TPE仍然是一个未满足的机会。通过从头设计和合成新型降冰片烯基ABA三嵌段共聚物,我们填补了这个空白。开环易位聚合(ROMP)用于制备具有前所未有的性能组合的TPE,包括皮肤样模量(<100kPa),与商用TPE(>5MPa)有竞争力,和类似于高性能塑料的较高工作温度(~260°C)。此外,这些材料是有弹性的,艰难,可再处理,和储存稳定(≥2个月),不掺入增塑剂。本文确定的结构-性质关系为下一代TPE的开发提供了信息,这些TPE既是生物柔软的又是热机械耐用的。本文受版权保护。保留所有权利。
With over 6 million tons produced annually, thermoplastic elastomers (TPEs) have become ubiquitous in modern society, due to their unique combination of elasticity, toughness, and reprocessability. Nevertheless, industrial TPEs display a tradeoff between softness and strength, along with low upper service temperatures, typically ≤100 °C. This limits their utility, such as in bio-interfacial applications where supersoft deformation is required in tandem with strength, in addition to applications that require thermal stability (e.g., encapsulation of electronics, seals/joints for aeronautics, protective clothing for firefighting, and biomedical devices that can be subjected to steam sterilization). Thus, combining softness, strength, and high thermal resistance into a single versatile TPE has remained an unmet opportunity. Through de novo design and synthesis of novel norbornene-based ABA triblock copolymers, this gap is filled. Ring-opening metathesis polymerization is employed to prepare TPEs with an unprecedented combination of properties, including skin-like moduli (<100 kPa), strength competitive with commercial TPEs (>5 MPa), and upper service temperatures akin to high-performance plastics (≈260 °C). Furthermore, the materials are elastic, tough, reprocessable, and shelf stable (≥2 months) without incorporation of plasticizer. Structure-property relationships identified herein inform development of next-generation TPEs that are both biologically soft yet thermomechanically durable.