Preparation of Inorganic-Organic Composites by Biomimetic Process and their Applications for Biomedial Materials

本文作者最近表明，当有机聚合物被浸泡在离子浓度接近于人血浆的模拟体液中，将其置于CaO、sio_2基玻璃颗粒上时，在有机聚合物上形成磷灰石核；当聚合物被浸泡在另一种相对于磷灰石过饱和的溶液中时，它们会自发地生长成致密连续的磷灰石层。本文研究了影响磷灰石聚合物成核速率和粘接强度的因素。用HCl溶液、NaOH溶液、紫外线和O_2气体辉光放电对聚合物进行预处理，明显提高了磷灰石的成核速率和粘接强度。其中，辉光放电处理对聚对苯二甲酸乙二醇酯、聚甲基丙烯酸甲酯、聚酰胺6、聚乙烯、聚醚砜和聚四氟乙烯等有机聚合物的性能均有显著影响。这是由于这些处理在聚合物表面形成了羰基、酯基、羧基和羟基等极性基团。当第二次处理的溶液中离子（不仅是阳离子，还有阴离子，如碳酸盐和羟基离子）的浓度被精确调整到与人类血浆中的浓度相等时，就形成了与骨骼中无机相相同的磷灰石。聚醚砜与表面磷灰石自发结合到活骨上。由此得到的磷灰石-聚合物复合材料被认为不仅可以用作硬组织的修复体，而且可以用作软组织的修复体。

The present authors recently showed that apatite nuclei are formed on organic polymers when the polymers are placed on CaO,SiO_2-based glass particles soaked in a simulated body fluid with ion concentrations nearly equal to those of human blood plasma, and that they grow spontaneously to from a dense and continuous apatite layr when the polymers are soaked in another solution supersaturated with respect to the apatite. In the present study, factors governing the nucleation rate and adhesive strength to the polymers of the apatite were investigated.Pretreatment of the polymers with HCl solution, NaOH solution, ultraviolet ray and glow discharge in O_2 gas appreciably increased the nucleation rate and adhesive strength of the apatite. Among them, the glow discharge treatment gave remarkable effects on such properties for all the organic polymers including polyethylene terephthalate, poly (methyl methacrylate) , polyamide 6, polyethylene, polyether sulfone and poly (tetrafluoroethylene) . This is attributed to the formation of polar group such as carbonyl, ester, carboxyl and hydroxyl groups on the polymer surfaces by these treatments. The apatite identical to the inorganic phase in the bone was formed when concentrations of ions, not only cations but also anions such as carbonate and hydroxyl ions, of the solution for the second treatment was adjusted exactly to be equal to those of human blood plasma. Poly-ether sulfone formed with the apatite on its surface spontaneously bonded to living bone. Thus obtained apatite-polymer composites are believed to be useful as prosthese of not only hard tissues but also of soft tissues.