Self-recoverable semi-crystalline hydrogels with thermomechanics and shape memory performance

热响应性自恢复、形状记忆半结晶水凝胶（英文）

Stimuli-responsive hydrogels have become one of the most popular artificial soft materials due to their excellent adaption to complex environments. Thermoresponsive hydrogels triggered by temperature change can be efficiently utilized in many applications. However, these thermoresponsive hydrogels mostly cannot recover their mechanical states under large strain during the process. Herein, we utilize the heterogeneous comb-type polymer network with semicrystalline hydrophobic side chains to design self-recovery semi-crystalline hydrogels. Based on hydrophilic/hydrophobic cooperative complementary interaction and heterogeneous polymer network, hydrogels can be endowed with excellent thermosensitive properties and mechanical performance. The hydrogels exhibit high compressive strength(7.57 MPa) and compressive modulus(1.76 MPa) due to the semi-crystalline domains formed by association of the hydrophobic poly(ε-caprolactone) PCL. The melting-crystalline transition of PCL and elastic polymer network provide the hydrogels excellent thermomechanical performance and self-recovery property. Furthermore, the hydrogels exhibit shape memory behavior, which can be realized by simple process and smart surface patterning. With these excellent properties, our hydrogels can be applied in sensors, flexible devices and scaffolds for tissue engineering.

热响应性水凝胶在组织工程、药物运输和柔性器件等领域有着广泛应用.但传统的热响应性水凝胶在大形变下回复性能差,而且一般需要复杂的化学合成.亲疏水二元协同作用可以使水凝胶网络具备优异的响应性和力学性能.基于此,我们制备了具有异质梳状网络的半结晶水凝胶.这种半结晶水凝胶以亲水的DMA和MEA作为网络框架,疏水的PCL聚集形成结晶微区作为热响应单元,表现出优异的力学性质、自恢复特性、热响应性机械性能和形状记忆的能力.