Pilate Florence, Wen Zhi-Bin, Khelifa Farid, Hui Yan, Delpierre Sebastien, Dan Luo, Mincheva Rosica, Dubois Philippe, Yang Ke-Ke, Raquez Jean-Marie
Laboratory of Polymeric and Composite Materials (LPCM), Center of Innovation and Research in Materials and Polymers (CIRMAP), University of Mons (UMONS) 23 Place du Parc 7000 Mons Belgium
Center for Degradable and Flame-Retardant Polymeric Materials (ERCEPM-MoE), National Engineering Laboratory of Eco-Friendly Polymeric Materials (Sichuan), State Key Laboratory of Polymer Materials Engineering, Sichuan University Chengdu Sichuan 610064 China.
RSC Adv. 2018 Jul 30;8(48):27119-27130. doi: 10.1039/c8ra03832e.
A novel poly(epsilon-caprolactone) (PCL) supramolecular network exhibiting shape-memory behavior was successfully constructed with pendant UPy units that are highly able to dimerize. The dynamic network was obtained by a simple and versatile strategy consisting of chain-extension reaction between α,ω-dihydroxyoligoPCL and hydroxylated UPy units in the presence of hexamethylene diisocyanate as a coupling agent and further intermolecular dimerization of the UPy along the polyurethane backbone. H NMR analyses confirmed the dynamic features of the system, and DMTA in tensile mode was investigated to assess the SMP properties. Recyclability was also assessed by taking advantage of these supramolecular networks. Further addition of cellulose nanocrystals into the polymer network enabled adjustment of the extent of the net-points and therefore the SMP features. As confirmed by dispersion tests in solution and SEM observations, these bio-based nanofillers were homogeneously distributed in the network supramolecular interaction between the hydroxyl groups present on their surface and UPy moieties along the polyurethane backbone. Thus, the here developed nanomaterials might reveal applicability in areas where a combination of SMP and biocompatibility is needed.
一种具有形状记忆行为的新型聚（ε-己内酯）（PCL）超分子网络通过具有高度二聚能力的侧基UPy单元成功构建。该动态网络通过一种简单通用的策略获得，该策略包括在六亚甲基二异氰酸酯作为偶联剂的存在下，α,ω-二羟基低聚PCL与羟基化UPy单元之间的扩链反应，以及UPy沿聚氨酯主链的进一步分子间二聚。1H NMR分析证实了该体系的动态特性，并采用拉伸模式的动态热机械分析（DMTA）来评估形状记忆聚合物（SMP）性能。还利用这些超分子网络评估了可回收性。向聚合物网络中进一步添加纤维素纳米晶体能够调节交联点的程度，从而调节SMP特性。通过溶液中的分散测试和扫描电子显微镜（SEM）观察证实，这些生物基纳米填料均匀分布在网络中，其表面存在的羟基与聚氨酯主链上的UPy部分之间存在超分子相互作用。因此，这里开发的纳米材料可能在需要SMP和生物相容性相结合的领域显示出适用性。
