The life of the hottest medical plastics can be gu

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Medical plastics - guaranteed life

in recent years, a number of raw material manufacturers have introduced new grades of plastics, which are specially suitable for applications in medical departments. However, one aspect that is often ignored is whether middlemen can fully compensate for the high investment required for particularly complex product development if only the formula of these materials remains unchanged for a long time

medical technology has developed into a promising plastic application field. In terms of total volume, although this part still occupies a relatively small share in the whole plastic market, it still shows inevitable and positive vitality. Standard plastics such as PVC, PE and PS account for the largest share of polymer materials used in medical applications, but engineering plastics also make an important contribution to market growth. BASF estimates that the annual growth of the demand for special plastics in the medical field is between 5% and 7%

the value-added potential related to hospitals, clinical and surgical fields attracts some manufacturers. However, the success of the medical sector has encountered relatively high prices. This paper will take the development of humicare 200 medical gas humidifier (Figure 1) of Grundler company in Germany as an example to illustrate this point

medical gas humidifier

in the process of artificial respiration in the intensive care unit, the plastic tube is inserted into the trachea to bypass the patient's upper respiratory organs (mouth, nose and throat). Therefore, the physiological cleaning, heat preservation and humidification functions of these organs have no effect. The gas supplied by the respirator to the patient directly enters the lower respiratory organs (trachea and bronchial system) without physical insulation and humidification in advance. Respirators used in hospitals usually run on compressed gas, and for reasons of hygiene and corrosion prevention, the gas from the central supply equipment is almost completely dry. In order to avoid the damage of dry air to respiratory organs and reduce the risk of pneumonia, it is absolutely essential to preheat and humidify the gas to a normal temperature coordinated with the human body. This is what humicare 200 humidifier developed by Grundler company does. Compared with its competitive system, it adopts new technology and brings significant advantages to patients, users and consumers

humicare 200 adopts a complex arrangement of terlux 2802 HD shaped discs. Terlux 2802 HD is a transparent thermoplastic based on methyl methacrylate, acrylonitrile, butadiene and styrene (mAbs). In the middle of 2004, BASF Ag added it to a series of special products for health care and medical diagnosis. These terlux discs (humicare 200 was the first to use this specially identified polymer) are covered with a liquid film. In this way, the flowing gas will be humidified, which is largely independent of the gas flow

the plastic parts of the medical gas humidifier humicare 200, the blue part in the figure is made of mAbs, such as the interior of the humidifier cavity

clearance certificate is essential

from a purely design point of view, the development project of the eight mAbs injection molded parts used in humicare 200 is not fundamentally different from that involved in the development of any other demanding plastic products, such as the automotive industry. However, the amount of labor required to complete the project is indeed not the same, so we will strive to do the same in the whole testing process, because the plastic ingredients used in the health care sector must comply with extremely strict regulations. At the top of the list of priorities is the need not to further damage the patient's health under any circumstances

therefore, the selection of potential plastics to meet such applications depends not only on the physical data of the material, but also on the biocompatibility of polymers and additives used in the formula. It also depends on the compatibility with some adhesive systems, which not only brings their adhesion to the extreme, but also has to have the ability to resist high-pressure sterilization

thoroughly check the data of the raw material manufacturer

in principle, as long as the manufacturer can prove the suitability of plastic, he can use any available plastic to meet a certain purpose of the medical department. However, he usually uses raw materials that have at least reliable evidence that they will meet specifications

nowadays, manufacturers choose from a range of plastics sold exclusively in the medical market by different suppliers. As has been said, it is very important to carefully check the effectiveness of commitments with products. For example, "medical grade" is not a legally protected term. What can well explain that plastic is suitable for the health care sector is that it can be used in contact with food with the permission of FDA for corresponding changes in relative error. However, this is only a basic requirement for the use of plastics in sensitive markets and cannot replace the implementation of detailed tests and the formal approval of the European Union or the United States Pharmacopoeia

the test is expensive

the terminal product is a component that directly contacts the patient. Basically, it must be confirmed that it meets the legal requirements. However, in individual cases, the agency designated to seek approval of these plastics may not have to ask for detailed evidence, provided that it can assume that the product will not cause harm under all possible circumstances. This is conceivable. For example, other medical products have used these plastics, and their safety has been documented. For injection molds (in this case, funk 3D of simmersfeld, Germany), there will be sufficient evidence of product consistency through the quality management system (such as ISO9001). DIN EN ISO standard "biological evaluation of medical products" defines the test procedures and the types of related tests

in order to comply with this standard and prove that their products are safe, in addition to the actual development work, manufacturers must draft a large number of risk analysis to determine which tests can provide evidence for the safety of their products. Whether the manufacturer is manufacturing mass-produced projects, which can be produced cheaply in other cases. This is not relevant. For example, test tubes, or very complex jackets for dialysis devices

selected medical plastic parts made of transparent mAbs, terlux 2802 tr q161, widely used in medical applications

in other words, compared with the products of other departments, the development, testing and approval procedures of medical products require a lot of extra labor. Therefore, the initial investment is huge. Individual tests and annual audits, including antibacterial tests such as biocompatibility or adhesive bonding, may take several weeks and require a lot of manpower. The test procedure used by Grundler to prove the safety of its humicare 200 medical gas humidifier took about a year, and the longer cycle is not uncommon. In this way, from prototype to final product, the cost of a single test program may easily exceed 10000 euros

the problem of long-term supply capacity

of course, these high costs must be compensated. The long-term life of products (usually we work based on the service life of about ten years) also brings other problems, because even medical technology products cannot be produced for inventory. Building a large amount of inventory will take up unnecessary funds, and the worst case is to make the necessary modifications to the product extremely expensive

therefore, the ability to supply the polymer used in this device for a long time is a major challenge, because in principle, any change in the formula is bound to lead to a high-cost reassessment of the final product, as well as all the costs associated with it. This problem affects not only the basic polymers (such as the content of short chain components), but also the whole formula, such as impact modifiers

in the long run, not all raw material manufacturers will realize the results of changing the formula of basic polymers on consumers in the small opportunity market of medical technology. BASF entered this market with its mAbs terlux 2802 HD (the abbreviation HD stands for health care and medical diagnosis). This transparent material has good stress cracking resistance and has been widely used in medical departments for a long time. Its name is terlux 2802 tr Q 161 (as shown in Figure 2). It complies with all specifications that form part of European and American legislation on the use of plastics in pharmaceutical and medical applications. For example, detailed tests on the granules showed that terlux 2802 HD fully met the requirements of European and American Pharmacopoeia (chapters 5.2 and 3.2.2 of European Pharmacopoeia and biological test classification VI of American Pharmacopoeia)

ensure long-term formula consistency

an intangible but significant advantage of the new transparent ABS grade is BASF's commitment to keep the formula of terlux 2802 HD completely unchanged, unless legislative changes require some form of modification to the formula. It should be announced at least 24 months in advance that due to this situation, the technical state and accuracy of the experimental machine need to be changed according to the difference of the comparison value, so as to give users enough adjustment time

basf's commitment is very important to users, which also extends to BASF's suppliers. They also promised to keep the quality of the additives they added to the formula unchanged. Only raw material suppliers regard themselves as partners of medical equipment manufacturers, this long-term cooperation will naturally succeed


terlux 2802 HD meets strict legislative requirements and controls the safety of end products designed for health care and medical diagnosis. This fact does not free the middlemen from the obligation to prove the safety of their products by their own tests. However, in some cases, the certificate provided by BASF (including the FDA signed drug management file) can simplify the final approval and licensing procedures

source: international plastic material business information

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