The Study On Preparation And Interface Of Nano-apatite Crystals/polyamide-66 Composites

Appropriate bone tissue replacement should be biocompatible and bioactive, which means to provide a chemical bond at the bone/implant interface; and have the mechanical properties equal to that of bone. If there are chemical bonds between the materials and the natural bone, it will prevent the formation of the fibrous tissue around materials; if the materials have mechanical behavior match of the natural bone, it will not lead to the bone absorption or unload-bearing due to its higher or lower mechanical properties. Polymers have good toughness and modulus similar to natural bone. Apatite (AP) forms the main mineral component of human bone, so it has excellent biocompatibility. Hydroxyapatite (HA) ceramics from AP can form a bone bonding with surrounding bone tissue. However, because of the brittleness, its application is usually restricted to unload-bearing situation. In order to increase the mechanical properties of HA, a new AP-reinforced polyamide composite was developed as bone replacement materials. The filler. AP. is a nano-meter-sized crystal, called n-HA; the matrix, polyamide-66, is a polar polymer. We expect the n-HAIPA66 composite will have good bioactivity, mechanical properties and chemical bonds between the two phases of the composite. The content and homogeneity of the n-HA in the composite was tested through burning test; IR, Raman Spectroscopy and XRD were employed to determine the interface between the n-HA and PA66. The result was that the content of the n-HA in the composite could be as high as that in bone; n-HAIPA66 composite had good homogeneity; and there are chemical bonds between the n-HA and PA66.