自愈水凝胶
化学
聚合物
PEG比率
两亲性
超分子化学
乙二醇
纳米尺度
氢键
高分子化学
化学工程
超分子聚合物
纳米技术
共聚物
分子
材料科学
有机化学
财务
工程类
经济
作者
Mingyu Guo,Louis M. Pitet,Hans M. Wyss,Matthijn Vos,Patricia Y. W. Dankers,E. W. Meijer
摘要
Hydrogels were prepared with physical cross-links comprising 2-ureido-4[1H]-pyrimidinone (UPy) hydrogen-bonding units within the backbone of segmented amphiphilic macromolecules having hydrophilic poly(ethylene glycol) (PEG). The bulk materials adopt nanoscopic physical cross-links composed of UPy–UPy dimers embedded in segregated hydrophobic domains dispersed within the PEG matrix as comfirmed by cryo-electron microscopy. The amphiphilic network was swollen with high weight fractions of water (wH2O ≈ 0.8) owing to the high PEG weight fraction within the pristine polymers (wPEG ≈ 0.9). Two different PEG chain lengths were investigated and illustrate the corresponding consequences of cross-link density on mechanical properties. The resulting hydrogels exhibited high strength and resilience upon deformation, consistent with a microphase separated network, in which the UPy–UPy interactions were adequately shielded within hydrophobic nanoscale pockets that maintain the network despite extensive water content. The cumulative result is a series of tough hydrogels with tunable mechanical properties and tractable synthetic preparation and processing. Furthermore, the melting transition of PEG in the dry polymer was shown to be an effective stimulus for shape memory behavior.
科研通智能强力驱动
Strongly Powered by AbleSci AI