髓核假体的制备及应力松弛特性的影响分析

对聚乙烯醇水凝胶髓核假体进行了应力松弛性能的研究,比较不同溶胀率和不同初始聚乙烯醇含量对应力松弛性能的影响.等时线法的研究分析表明,髓核假体的力学行为符合线性粘弹性行为,三元件线性粘弹模型能较好地模拟其粘弹力学行为(模拟拟合度均在0.96以上).三元件线性粘弹模型参数分析表明,对于髓核假体来说,溶胀率的增大可以增加髓核假体消散冲击力的速度,但对消散冲击力的总量影响不大,初始PVA含量的提高将降低髓核假体消散冲击力的速度和总量.

Manufacture of prosthetic nucleus and analysis of stress-relaxation properties

Isochronal plots and a three-parameter linear viscoelastic model were used to characterize the stressrelaxation properties of PVA-H prosthetic nucleus and to analyze the influence of swelling ratio and initial PVA content upon the stress-relaxation properties. The results ofisochronal plots showed that PVA-H prosthetic nucleus followed a linear viscoelastic mechanical property. The three-parameter linear viscoelastic model can simulate the viscoelastic property of prosthetic nucleus well with the fitness more than 0.96. It can be seen from the analysis of parameters in the model that the increase of the swelling ratio will greatly increase the speed of dissipated stress of the prosthetic nucleus, and does not have too much influence on the total dissipated stress; but the increase of the initial PVA content will decrease both the speed and the total of the dissipating stress.