Many plastic materials with non-toxic, harmless, lightweight and other characteristics, is widely used in the medical industry, and in the next few years, the demand for medical plastics will greatly exceed the demand for glass, metal and other raw materials, the main plastic materials can be divided into the following:
　　聚氯乙烯(PVC，Polyvinylchloride)
PVC is one of the largest plastic varieties in the world. PVC resin is white or light yellow powder, pure PVC is atactic, hard and brittle, rarely used. According to different uses, different additives can be added to make PVC plastic parts present different physical and mechanical properties. Adding an appropriate amount of plasticizer to PVC resin can be made into a variety of hard, soft and transparent products.
Hard PVC does not contain or contains a small amount of plasticizer, has good tensile, bending, compression and impact resistance, can be used alone as a structural material. Soft PVC contains more plasticizers, its flexibility, elongation at break, cold resistance increased, but the brittleness, hardness, tensile strength decreased. The density of pure PVC is 1.4g/cm3, and the density of PVC plastic parts added with plasticizers and fillers is generally in the range of 1.15-2.00g/cm3.
According to market estimates, about 25% of medical plastic products are PVC. This is mainly due to the low cost of the resin, its wide range of applications, and its ease of processing. Medical application of PVC products are: hemodialysis pipeline, breathing mask, oxygen tube, etc.
Polyethylene (PE,Polyethylene)
Polyethylene plastic is the largest variety in the plastics industry, Milky White, tasteless, odorless and non-toxic shiny waxy particles. It is characterized by low price and good performance, and can be widely used in industry, agriculture, packaging and daily industry, and occupies a pivotal position in the plastics industry.
PE mainly includes low density polyethylene (LDPE), high density polyethylene (HDPE) and ultra high molecular weight polyethylene (UHDPE) and other varieties. HDPE has fewer branched chains on the polymer chain, higher relative molecular mass, crystallinity and density, higher hardness and strength, poor opacity, and higher melting point. It is commonly used in injection molded parts. LDPE has many branched chains, so the relative molecular mass is small, the crystallinity and density are low, and it has good flexibility, impact resistance and transparency. It is commonly used in blown film and is an optional substitute for PVC, which is widely used at present. HDPE and LDPE can also be mixed according to the performance requirements. UHDPE has high impact strength, low friction, stress crack resistance and good energy absorption characteristics, making it an ideal material for artificial hip, knee and shoulder connectors. Polypropylene (PP,polypropylene)
Polypropylene is colorless, odorless and non-toxic. Looks like polyethylene, but more transparent and lighter than polyethylene. PP is a thermoplastic with excellent performance, with a small proportion (0.9g/cm3), non-toxic, easy processing, impact resistance, flexibility and other advantages. It has a wide range of applications in daily life, including woven bags, films, turnover boxes, wire shielding materials, toys, car bumpers, fibers, washing machines, etc.
Medical PP has high transparency, good barrier and radiation resistance, which makes it widely used in medical equipment and packaging industry. The Non-PVC material with PP as the main body is the substitute of PVC material which is widely used at present.
With the continuous growth of China's national economy, medical and health care is also growing, and the domestic medical plastics industry should be the development of new medical plastic products included in the development plan, in order to meet the modern society people's demand for the continuous improvement of the quality of medical and health services, I believe that in the future, medical plastic products will have better and greater development.