基于氢键自修复的交联型聚酰胺胺化学凝胶的制备与性能研究

通过试管倒立法和流变学测试对交联型聚酰胺胺凝胶的形成进行了判定。实验结果表明,直观的试管倒立法对聚酰胺胺凝胶形成的判定是有效的。通过对影响凝胶形成的各因素分析发现,在R=1.25、反应温度50℃、甲醇溶剂中制备的凝胶在单体质量浓度大于22%时能够形成凝胶,且符合IPN凝胶的制备要求。通过对聚酰胺胺(PAMAM)、N,N-亚甲基双丙烯酰胺(MBA)和N-氨乙基哌嗪(AEPZ)的红外分析可以看出,本文中MBA与AEPZ可以发生交联反应,生成PAMAM,同时对加入LiBr的PAMAM和未加入LiBr的PAMAM红外分析表明,交联聚酰胺胺中含有丰富的氢键相互作用,为材料的自修复提供了可能。通过对PAMAM-1(单体质量浓度22%)、PAMAM-2(单体质量浓度27%)和PAMAM-3(单体质量浓度32%)的平衡溶胀率测试可以看出,PAMAM-1具有最大的溶胀率。通过对三者的动态模量测试,PAMAM-1、PAMAM-2和PAMAM-3的G′分别为5000Pa、15000Pa和24000Pa,说明凝胶具有良好的弹性。以PAMAM-3为例表征了材料的自修复过程,表明制备的交联型聚酰胺胺能够通过氢键及物理的相互作用对材料进行修复,在药物缓释等方面有潜在应用。

Preparation and Properties of Crosslinked Polyamide Amide Gels Based on Hydrogen Bond Self-Repair

The formation of polymer gels are judged by inverted test tube method and rheological test.The results show that these methods are effective during determining its formation.And according to the analysis of various factors affecting gel formation,it was found that the gels can be prepared when they are in the methanol solvent,R=1.25,50℃and the monomer concentration(mass fraction)over 22%.Through the infrared analysis of polyamide amine(PAMAM),N,N-methylenebisacrylamide(MBA)and N-aminoethylpiperazine(AEPZ),it shows that the chemical crosslinking reaction between MBA and AEPZ can be happened and PAMAM is then generated.And infrared analysis of PAMAM with LiBr and PAMAM with no LiBr showed that the cross-linked polyamide amine contained rich hydrogen bonds interaction,which provided a possibility for self-repair of the material.The equilibrium swelling ratio tests of PAMAM-1(monomer concentration 22%),PAMAM-2(monomer concentration 27%)and PAMAM-3(monomer concentration 32%)show that PAMAM-1 has the highest swelling ratio.Through the dynamic modulus tests,we know that the G′of PAMAM-1,PAMAM-2 and PAMAM-3 are 5000 Pa,15000 Pa and 24000 Pa respectively,indicating that the gels had good elasticity and belonged to chemical crosslinking.The self-repairing process of the material was characterized by PAMAM-3,which indicated that the cross-linked polyamide amine can be repaired by hydrogen bonds and physical interaction,and has potential applications in drug release.