Dean Leon M, Wu Qiong, Alshangiti Omar, Moore Jeffrey S, Sottos Nancy R
ACS Macro Lett. 2020 Jun 16;9(6):819-824. doi: 10.1021/acsmacrolett.0c00233. Epub 2020 May 26.
Rapid, solvent-free synthesis of poly(1,4-butadiene) in ambient conditions is demonstrated by frontal ring-opening metathesis polymerization (FROMP) of 1,5-cyclooctadiene (COD). Furthermore, cross-linked copolymers with a wide range of tunable properties are readily prepared by FROMP of mixtures of COD and dicyclopentadiene (DCPD). Specifically, glass transition temperature and tensile modulus are varied from -90 to 114 °C and 3.1 MPa to 1.9 GPa, respectively, by controlling the comonomer ratio. Copolymers with subambient glass transition temperature exhibit robust elastomeric behavior, with the ability to repeatedly recover from large elastic deformations. As a demonstration of the capability of this manufacturing strategy, gradient materials are fabricated in less than a minute with spatially controlled properties for multistage shape memory actuation. This simple yet powerful manufacturing strategy enables rapid synthesis of copolymers ranging from elastomers to thermosets with precise control over thermomechanical properties.
通过1,5-环辛二烯（COD）的前沿开环易位聚合（FROMP），在环境条件下实现了聚（1,4-丁二烯）的快速无溶剂合成。此外，通过COD和二环戊二烯（DCPD）混合物的FROMP可以轻松制备具有广泛可调性能的交联共聚物。具体而言，通过控制共聚单体比例，玻璃化转变温度和拉伸模量分别在-90至114°C和3.1MPa至1.9GPa之间变化。具有低于环境温度玻璃化转变温度的共聚物表现出强大的弹性体行为，能够从大的弹性变形中反复恢复。作为这种制造策略能力的证明，在不到一分钟的时间内制造出具有空间控制性能的梯度材料，用于多级形状记忆驱动。这种简单而强大的制造策略能够快速合成从弹性体到热固性的共聚物，并对热机械性能进行精确控制。
