pH-敏感的疏水型凝胶在直流电场中的刺激响应

合成了不同疏水链长的甲基丙烯酸酯、甲基丙烯酰胺及丙烯酸与 4 ,4′ 二 (甲基丙烯酰胺基 )偶氮苯交联共聚的聚电解质凝胶 .该凝胶在非接触电场中发生消溶胀 ,但疏水侧链较长的凝胶在发生消溶胀之前经历了一个溶胀过程 .凝胶在电场中首先弯向阴极 ,随着时间的延长或电压的升高弯向阴极 ;并出现弯曲的方向或弯曲的程度的波动 .当撤去电场后 ,凝胶又能恢复到初始的形态 .凝胶的这些性质既与电渗、电扩散及电解有关 ,亦与凝胶的疏水相互作用有关

STIMULI RESPONDSE OF pH-SENSITIVE HYDROPHOBIC HYDROGELS UNDER DC ELECTRIC FIELDS

Polyelectrolyte hydrogels based on n alkyl methacrylate esters( n AMA),acrylic acid and acrylamide cross linked with 4,4′ di(methacryloylmino)azobenzene were prepared.The deswelling of gels was observed under non contact electric fields,while the gels with the longer hydrophobic side chains proceeded as welling before deswelling.The gels first bend toward the cathode under non contact electric fields,and the direction or degree of bending waves with the passage of time or when higher voltages are applied.The gels can turn back to the original swollen shape when the electric field is removed.These properties of the gels are related to electro osmosis,electrodiffusion,electrolysis,and hydrophobic interactions.