基于Pickering乳液的磁性高强水凝胶的制备及性能表征

合成了一种磁性Fe3O4纳米颗粒稳定的水包油(O/W)Pickering乳液并以其作为交联剂,在适宜条件下引发单体丙烯酰胺聚合来制备了一种新型的磁性高强复合水凝胶.采用X射线衍射(XRD)及场发射扫描电子显微镜(SEM)分别对磁性Fe3O4纳米颗粒和复合水凝胶的结构进行了表征,结果表明Pickering乳胶粒子较均匀地分布在复合凝胶网络中.溶胀性能测试及溶胀动力学分析表明复合水凝胶具有良好的溶胀性能,能够吸收自身干重100倍左右的水,其溶胀过程不遵循Fickian扩散模型;拉伸测试表明该水凝胶具有优异的力学性能,其拉伸强度能够达到150 kPa左右,断裂伸长率能够达到300%左右,并且当其承受的应力释放后能快速地恢复到初始形态.磁性能测试的结果显示该水凝胶具有良好的磁性.

PREPARATION AND CHARACTERIZATION OF MAGNETIC HYDROGELS WITH HIGH STRENGTH BASED ON PICKERING EMULSION

A Fe3O4 nanoparticles-stabilized Pickering emulsion,which is a kind of emulsion stabilized by solid particles instead of traditional surfactants,was used as a cross-linking agent.And a novel composite hydrogel was prepared by initiating monomer acrylamide in the appropriate condition.The structure of nanoparticles and composite hydrogel was characterized through X-ray diffraction(XRD) measurements,and field-emission scanning electron microscope(SEM),respectively.Moreover,the properties of hydrogels were studied by swelling ability measurements and swelling kinetics analysis,mechanical test and magnetic response test.It can be found from SEM images that the TPM droplet acted as a cross-linking agent in the reactive system and distributed in the hydrogel network orderly.Swelling test indicated that the composite hydrogels had excellent swelling capacity in comparison to conventional hydrogels,and even could swell to about 100 times of their dry weight.And swelling kinetics analysis results showed that the swelling process of the composite hydrogels did not follow the Fickian swelling kinetics model.The mechanical test results showed that the composite hydrogel exhibited outstanding mechanical performance.The composite hydrogels showed a strength of 150 kPa and high elongation at break of 300%.Moreover,the composite hydrogels could return to original state after stretching to several times of its original length quickly and even could make into a knot without damage.Magnetic response test results indicated that the composite hydrogels exhibited a clear magnetic response.