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

本文作者最近发现，当聚合物置于CaO，SiO_2基玻璃颗粒上，浸泡在离子浓度接近于人血浆的模拟体液中时，磷灰石核在有机聚合物上形成;当聚合物浸泡在另一种相对于磷灰石过饱和的溶液中时，磷灰石核自发生长，形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附着强度的因素，用HCl溶液、NaOH溶液、紫外线和O_2气体中辉光放电预处理聚合物，可明显提高磷灰石的成核速率和附着强度。其中，辉光放电处理对聚对苯二甲酸乙二酯、聚甲基丙烯酸甲酯、聚酰胺6、聚乙烯、聚醚砜和聚对苯二甲酸乙二酯等有机高分子材料的力学性能有显著的影响。这是由于这些处理在聚合物表面上形成了极性基团如羰基、酯基、羧基和羟基。当用于第二处理的溶液的离子浓度（不仅是阳离子，而且还有阴离子如碳酸根和氢氧根离子）被精确地调节到与人血浆的浓度相等时，形成与骨中的无机相相同的磷灰石。聚醚砜表面的磷灰石与活骨自发结合而成。由此获得的磷灰石-聚合物复合材料被认为不仅可用作硬组织的假体，而且可用作软组织的假体。

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.