Medical plastics have a broad market, and their performance requirements are generally relatively high, especially in terms of thermal stability, biocompatibility, drug compatibility, and environmental protection. There are relevant national and industry standards. Passports in related fields.
Easy oxide is a very special name. Many friends may hear it for the first time, but it is very common in the medical industry. It is often encountered that easy oxides exceed the standard on materials such as medical devices or medical packaging. What is easy oxide? Refers to substances that are prone to chemical reactions with oxygen in ordinary environments.
For example, iron, aluminum, copper, etc., the common and easy-to-understand metals are those that are easy to rust. However, in the medical industry, it generally refers to many substances that are easily oxidized with oxygen. Organics, metal powders, reducing agents, sulfur, phosphorus and other combustibles, human cells, cell membranes and fatty acids are all easily oxidized. The content of easily oxidized packaging materials is the main technical standard of the country.
Medical PVC plastics are usually used for disposable blood transfusion (liquid) appliances, oxygen inhalation tubes, urinary catheters, oxygen masks and other products and medical device accessories. At the same time, because of ideal transparency and suitable cost, pharmaceutical PVC packaging sheets also occupy a large share in the field of pharmaceutical packaging materials.
Because PVC is a heat-sensitive plastic, many raw materials such as heat stabilizers, lubricants, enhancers or modifiers are generally added during formulation production. The reason for adding these raw materials is to make PVC easier to process and use.
Although many raw materials are ideal, they are not allowed to be used in the field of medical PVC. The easy oxides in the field of medical plastics are caused by many factors such as insufficient thermal stability, excessive added raw material oxides, poor stability in later use, and storage conditions. The main reason for the excess of the easy oxides is that the metal atoms or molecules are freed or shed during the production process of the formula, and the reaction with oxygen leads to the survival of the easy oxides.
Don't underestimate the role of non-toxic phosphite as an auxiliary heat stabilizer. It can effectively chelate the metal atoms or molecules that fall off, and at the same time, it has a clumping effect with the hydrogen falling off from polyvinyl chloride. The easy oxides exceed the standard, so this point needs to pay attention to the purity of the raw materials.