【摘要】 选用高分子聚乙烯醇(PVA)和纳米羟基磷灰石(HA)为原料,采用反复冷冻-解冻法制备PVA/HA复合水凝胶。利用光学显微镜考察PVA/HA复合水凝胶的溶胀性能,用精密位移传感器对PVA/HA复合水凝胶的接触变形特性进行测量,在小牛血清稀释液润滑条件下进行PVA/HA复合水凝胶的往复式摩擦试验,考察冷冻-解冻次数和接触时间对PVA/HA复合水凝胶启动摩擦性能的影响。结果表明:PVA/HA复合水凝胶是一种交联网状微观结构,溶胀性能优异;随着冷冻-解冻次数的增加,PVA/HA复合水凝胶交联度增大,网状结构趋于完善,其接触变形越小,恢复变形所需的时间越短;PVA/HA复合水凝胶在滑动过程中的法向位移量和启动摩擦因数随反复冷冻-解冻次数的增加而减小,随接触时间的延长而增大。更多还原

【Abstract】 The polyvinyl alcohol/hydroxylapatite(PVA/HA)composite hydrogel was prepared by reiterative freezing-thawing method using the raw materials of macromolecular PVA and nano-HA.The swelling properties were investigated by using the optical microscope.The contact deformation of PVA/HA composite hydrogel was measured using an exact displacement sensor.The influence of freezing-thawing times and contact time on the friction properties of start-up of PVA/HA composite hydrogel in the diluted bovine serum solution was studied by reciprocating sliding tests.The results show that the PVA/HA composite hydrogel has a cross-linkage and netlike construction,which has excellent swelling property.The cross-linking degree of the PVA/HA composite hydrogel increases and the network structure tends to perfect with the increasing of freezing-thawing cycles.The contact deformation and the restoration time of deformation are inversely proportional to the freezing-thawing cycles.The normal displacement and the start-up friction coefficient of PVA/HA composite hydrogel decrease with the increasing of the freezing-thawing times,and they increase with the increasing of contact time.更多还原