Shaanxi Yunzhong Industry Development Co.,Ltd
Address: NO.128 Gaoxin Road, Baoji City, Shaanxi Province of China
Abstract: the biomedical composite material (biomedical composite materials by two or more than two kinds
of different materials composite and biomedical materials it is mainly used for manufacture of repairing and
replacement of human tissues and organs of the human body. Long term clinical application found that the
traditional medical metal materials and polymer materials with biological activity, organization and is not
easy to firmly combined, of environmental and physiological effects in the physiological environment or
implanted in the body, resulting in metal ion or monomer release, resulting in adverse effects on the body.
And biological ceramic material although has good chemical stability and compatibility, high strength and
wear resistance, corrosion resistance, but the bending strength of the material is low, high brittleness, in the
physiological environment of fatigue and breaking strength is not high, in did not fill strong measures under,
it is only used to carry a load, or bear only net compressive stress situation. Therefore, the single material can
not meet the requirements of clinical application. Using the different properties of the composite and
biomedical composite material, has both the properties of materials and get a group of single material does
not have the new performance, in order to obtain the structure and properties similar to human tissue for
biomedical materials opens up a broad way diameter, biomedical composite material will become the most
active in the field of biomedical materials research and development.
An overview of biomedical composite materials:
1, the development of the situation:
With the progress of social civilization, economic development and the improvement of living standards,
people pay more attention to their own medical rehabilitation. At the same time, social rapid population
growth, traffic tools in large numbers, the quickening pace of life, diseases, natural disasters, accidents,
sports injuries and injuries occurred frequently, resulting in accident surge to the people. Therefore, the
development of Bio Medical Materials for human tissue and organ regeneration and repair is of great social
benefit. Prospects for dentures in early BC 3500 years, Egyptian cotton fiber, the horsehair suture wound;
Mexican Indians by wood repair injured skull; BC 500 years of Chinese and Egyptian tombs were found,
fake nose and ear prosthesis. In 1936, the invention of the organic glass, soon making dentures and dental, so
far is still in use. In 1949, the United States first published medical polymer papers, first introduced by using
PMMA as the skull bone, joint and femur using polyamide fiber as a surgical suture the clinical application;
50 years, silicone polymer is used in medical field, accelerate the organ substitution, cosmetic, development.
So we can see that these materials used in the repair of human organs have a long history of development,
they are referred to as biomedical materials.
Biomedical material is a new kind of material, has a wide application prospect, only high molecular material,
around the world in the medical application of have more than 90 varieties, more than 1800 kinds of
products and consumed by the western countries in the medical polymer materials each year at a rate of 10%
~ 20% growth. With the development of modern science and technology, especially the great breakthrough
of biological technology, the application of biological materials will be more extensive.
As biomedical materials are a newly developed field, there is no strict definition. This was interpreted as
follows: biomedical materials is to implant organisms or combined with biological tissue material. It can be
used for diagnosis, treatment, and the replacement of organisms in the tissues, organs, or enhance their
functions. These materials are used for hard tissue and soft tissue repair and replacement by long term, short
term and surface repair.
According to the composition and properties of materials:
Medical polymer materials (polyethylene, polyurethane, PTFE, poly methyl methacrylate, silicone rubber,
poly lactic acid, poly hydroxy acetic acid);
Medical metal materials (stainless steel, cobalt based alloys, titanium and titanium alloys, and precious
、Medical ceramic materials (hydroxyapatite);
edical composite materials (metal matrix ceramic coating system, etc.).
Biological chemical reaction level in the physiological environment:
Inert biomedical materials, biological active materials, biodegradable and absorbed biological materials
According to the use of:
Skeletal muscle system repair materials and replacement materials (bone, tooth, joint, tendon)
Soft tissue material (skin, breast, esophagus, respiratory bladder)
Cardiovascular system materials (artificial heart valve, blood vessel, cardiovascular intubation)
Medical membrane material (blood purification membrane and separation membrane, gas selective permeation membrane, corneal contact lens)
Drug release materials, etc..
4, biological and medical composite material selection requirements
Due to the complexity of the human body physiological environment, the implanted medical materials will have long-term physical, chemical and biological factors and the biological tissue or organ exists many dynamic interactions, so biomedical materials need to meet the following requirements:
Good organization and physical compatibility;
Has excellent chemical stability, that is, the structure or nature of the medical material is not due to the biological environment and the role of changes, while the medical material can not cause the rejection of organisms;
(3) has excellent mechanical properties, namely medical materials should have sufficient mechanical strength and flexibility and to withstand mechanical forces in biological and medical materials selected to biological tissue and the tensile and bending strength, modulus, hardness and wear resistance is consistent;
It has antibacterial properties and process of forming excellent performance, not because of the machining difficulties which restricted its application .
Two. Research status of biomedical composites
Two. Research status of biomedical composites
According to the different matrix materials, biomedical composites can be roughly divided into three types, metal based, Tao Ciji and polymer matrix composites. Through the corresponding process forming method, all kinds of materials are made into biological composite materials in different medical application fields.
1, metal based biomedical composite materials
Metal matrix biomedical composite materials, such as stainless steel, titanium alloy, compared with the traditional medical materials, medical metal matrix composite material with high mechanical strength, excellent flexibility, fatigue resistance performance is good, excellent molding process. But the single metal materials in the application of the physiological environment is facing an important problem of corrosion, metal ions to the biological tissue diffusion will cause toxic side effects, and the degradation of its own nature is easy to lead to implant failure. Therefore, it is not easy to corrosion and has a good biocompatibility of the metal matrix biomedical composite material is a new type of research personnel to be developed.
When it comes to metal materials, the first people will think of titanium based materials. Medical titanium material due to its high strength, toughness and good molding process is widely used artificial bone and artificial joint, root material. Titanium surface modified titanium matrix coating composite material. It not only has sufficient strength and toughness, but also has good biocompatibility, is considered to be one of the advantages of metal materials and other materials in the most effective way. Milella  by adding a small amount of water in the alcohol solution of titanate with the sol - gel technology., ester hydrolysis polymerization of a polymeric colloid. In the solution, the samples were extracted, dried and heat treated at high temperature, and titanium gel was prepared on titanium and titanium alloy surface. If you add salt and calcium phosphate in the TiO2 sol, composite coating containing calcium and phosphorus. Selection of different Ca/P/Ti ratio, multiple extraction, the coating of the composition is a gradient distribution. Between the coating and the substrate is the calcium phosphate and titanium, calcium and phosphorus concentration from the outside to the inside, while the titanium content is just the opposite. After the implantation of the human body showed good biocompatibility. Zhu Minggang  using the same sol gel method, by the mass ratio of 2. 86: trimethyl 1 calcium nitrate and phosphate in the preparation of the sol solution, through multiple coating, sintering, on the surface of the titanium metal support the porosity for 12% of the HA bioactive coating. The formation of a layer of Ti, Ca, P component transition zone, tensile experiments show that the interfacial bonding strength of 28MPa.
At the same time, medical titanium alloy has been widely used in clinical practice. Su Xiangdong  of NiTi alloy biocompatibility of research show that, pH in the acidic, neutral and alkaline range, 0. 9% NaCl physiological fluids, Hank's simulated body fluids, Tyrode's simulation blood redox potential different NiTi alloy in Ni ion release amount of a difference, which Tyrode's simulation of Ni ions in the blood to release a quantity to higher; NiTi alloy Ni ion release amount of influence with the simulated body fluid pH value decreases with Cl - concentration increased and increased; NiTi alloy in physiological fluids showed strong Ni element selective corrosion behavior, Ti corrosion weak, pitting is the main corrosion.
2, Tao Ciji biomedical composite
In ceramics, glass as the substrate material of ceramic matrix composites is a has the broad application prospect of medical materials, it is through the wafer, whiskers, particles, fibers, and other different reinforcing material into the ceramic obtained of a kind of composite material. The literature data shows that the total content of calcium and phosphorus in human bones has reached 58%, so many researchers have developed calcium phosphate ceramics as a bone graft material. Early use of ceramic materials in the life of the body can not be bonded with bone tissue, such as alumina ceramics, to the 70's appeared a number of bioactive ceramic. With the clinical application, bioactive ceramics as a bone repair material gradually began to be applied. However, the bio ceramic material itself has the characteristics of low bending strength and poor elastic properties, so it can not meet the development of the current medical level. However, after the combination of bioactive ceramics and other materials, a kind of ceramic based biomedical composite material with different properties and new properties was formed.
Towler  through the use of sintered ZrO2 nano materials by the high relative density HAP-ZrO2 bioceramic composite materials, in order to reduce the sintering temperature and the use of nano ZrO2, ha at high temperatures will not break down, ha phase is the main phase. In the traditional sintering process, this kind of decomposition often occurs, and compared with pure HA, the strength of the composite is higher than that of the former. Huang Chuanyong and so on  prepared by chemical co precipitation method and two ultrafine zirconia powder, through the optimization of the combination of different materials, the preparation of HAP-ZrO2
The composition and microstructure of the materials were revealed by infrared spectrum analysis, X-ray diffraction, scanning electron microscope and transmission electron microscope. The composition and microstructure of the two element system were also revealed. The bending strength of the two element system of biological ceramic composite HAP-ZrO2 reached 120MPa, the fracture toughness reached 1 M-1 /2 74MPa, the performance was almost two times that of pure HA, which was close to the human bone tissue. The bending strength of dense human bone can reach 160MPa, and the fracture toughness is 2 M-1 / /2 2MPa. The results showed that the biological ceramic composites had good performance in the aspects of mechanical properties, chemical stability and biocompatibility. At present, foreign countries have been prepared