PNaAMPS/PAAm水凝胶在NaCl水溶液中的力学与摩擦性能

Mechanical and frictional behavior of PNaAMPS/PAAm hydrogel in NaCl aqueous solution

通过改变离子强度的大小,研究了聚2-丙烯酰胺-2-甲基丙磺酸钠/聚丙烯酰胺(PNaAMPS/PAAm)这种双网络水凝胶的溶胀性能、力学性能和摩擦性能。由于离子会对水凝胶中高分子链的状态产生影响,研究发现随着离子强度的增大,溶胀率首先呈迅速下降的趋势,在0.2mol/kg之后溶胀率下降变缓。拉伸强度对离子强度变化不明显。撕裂时的断裂能随着离子强度的增大,首先呈下降的趋势,0.2mol/kg之后断裂能变化不大。压缩模量随着离子强度的提高而增大,在0.8mol/kg时达到最大值。摩擦行为中,在低离子强度时,其摩擦性能表现出一种"静摩擦"现象,而在高离子强度(临界值为0.8～1.0mol/kg)时,摩擦力显著增大,并且摩擦应力曲线呈现出典型的吸附模型性质。

The swelling degree,mechanical and frictional behavior of poly（2-acrylamido-2-methylpropanesulfonic acid sodium salt） / poly（acrylamide）（PNaAMPS/PAAm） hydrogel in the solutions of varies ionic strengths have been investigated.Results showed that the swelling degree decreased rapidly with the increase of ionic strength at the beginning.After 0.2mol/kg ionic strength,the curve decreased slightly.The tensile strength was not sensitive to ionic strength.For the tearing test,the fracture energy decreased with the increase of ionic strength at first.After 0.2mol/kg ionic strength,the fracture energy was not sensitive to ionic strength.The compression modulus increased with the increase of ionic strength.When the ionic strength was 0.8mol/kg,the compression modulus reached the maximum value.For the frictional behaviors,at low ionic strength,the friction showed a behavior of ＂static friction＂;at high ionic strength,e.g.0.8-1.0mol/kg,the frictional stress increased relative to the lower.And the curves of friction was similar to adsorption model.