STUDY AND CHARACTERIZATION OF PP/HYDROXYAPATITE COMPOSITES

摘要

The use of metals, ceramics and metallic alloys in the design of prothesis is very well known from long time ago. These are implanted in the body to correct defects caused by an accident or by some congenic problems. The biomaterials used to replace a living part of the human body should funtion without producing any adverse reaction. The biological behavior that influences directly the degree of acceptance of the receptor organism to the foreign body is called biocompatibility. Many years of experience have demostrated that most of the materials mention above are not completely inert to the body fluids neither possess the appropriate chemical structure for perfectly bonding to the body tissues, stablishing a good interaction. Polymers such as PP, on the other hand, are almost completely inert with the body fluids and exhibit a minimum chemical interaction with the adyacent tissue. However, one type of material alone is not able to fulfill all the requirements for a specific application. Nowdays composites based on polymers and a reinforced load such as hydroxyapatite (HA) are promissing materials for biomedical applications. These materials are developed pointing towards the solution of the biocompatibility problems. Why composites represent a promisse in biomedicine applications?. The ossean tissue is a composite itself formed by collagen matrix and reinforced by mineralized bone. This is similar to a polymer matrix reinforced with hydroxyapatite crystals. Composites sinergistically combine the excellent mechanical properties of polymers with the high porosity and compatibility of hydroxyapatite, to generate materials that are being used in traumatology, cardiology and oftalmology.