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In response to the "three no problems" exposed by outdoor fire hydrants during the company's comprehensive emergency rescue plan drill on May 21: inadequate maintenance, unclear responsibilities, and lack of attention to thinking, Anhuan Branch quickly carried out a special inspection of fire-fighting facilities according to the requirements of the company's senior management, and aimed at the problems existing in the inspection, measures such as reporting the purchase plan of fire fighting facilities, defining the responsible person of fire fighting facilities, limiting the maintenance time and carrying out accident case warning education in the company's safety management group have been taken successively to add insurance to the company's fire fighting red line in a timely manner.

"Promoting the environmental protection process of heat stabilizers and accelerating the pace of banning lead in the PVC products industry is the general trend of the development of China's plastics industry." Cao Jian, executive vice president of the China Plastics Processing Industry Association, said that accelerating the environmental protection process of the PVC products industry is not only a requirement of the external environment for the plastics processing industry, but also the plastics industry itself to accelerate structural adjustment, enhance innovation-driven capabilities, and achieve industrial upgrading. And the inherent needs of sustainable development. Plastic products are closely related to people's lives, and ensuring the safety of plastic products is the social responsibility and obligation of the plastic industry. China is already a producer and consumer of PVC resin and products in the world, and PVC products are playing an increasingly important role in all walks of life in the national economy and in all aspects of people's lives. At the same time, the safety of PVC products has also attracted much attention. The development, promotion and application of safe, environmentally friendly and excellent performance stabilizers to replace lead salt stabilizers is a major event related to the development of the industry and the health and safety of the people. Shi Xun, vice chairman of the Plastic Additives Committee of the China Plastics Association, told reporters that as early as the beginning of this year, the China Plastics Association had organized a seminar on the production and application of alternative lead-containing heat stabilizers in Guangzhou. At the meeting, a leading group was also set up for the removal of lead from heat stabilizers for PVC products, led by the China Plastics Association, with the participation of the Additives Committee, Plastic Pipes Committee, and Special Profiles and Special Committee. With the improvement of environmental awareness from all walks of life and the continuous increase of environmental protection efforts of relevant government departments, the environmental protection and de-lead of plastic additives have become the only way for the sustainable development of the plastic industry, and the replacement of lead salt stabilizers will also enter Substantive stage. For PVC products, the ban on lead work, if Shi Xun has been maintaining an attitude. Since the establishment of the Heat Stabilizer Branch of the Special Committee on Plastic Additives in 2006, he has constantly reminded that it is sooner or later for China's PVC industry to ban lead, and enterprises should make technical reserves in advance. This understanding is due to his in-depth understanding of the development trend of the international PVC industry and relevant environmental protection and safety regulations. For many years, Shi Xun has been tracking international development trends. He told reporters that as early as the 1990 s, when he visited a stabilizer manufacturer in the United States, he found that American companies at that time had already begun lead-free work. A lot of technical research and development, and overcome the technical problems in the application of non-lead stabilizers. In the 21st century, the lead-free process of heat stabilizers in Europe continues to advance, and this wave has also directly spread to China, because China's exports to Europe of toys, calendered films, and profile hard products and electronic and electrical products meet European environmental standards.

Medical plastics have a broad market, performance requirements are generally relatively high, especially thermal stability, biocompatibility, drug compatibility, environmental protection and other aspects have relevant national and industry standards, only to meet the standards, in order to obtain a pass in the relevant fields. Easy oxide is a very special name. It may be the first time many friends have heard of it, but it is very common in the medical industry. Often encountered in medical equipment or medical packaging materials such as the above encounter easy to exceed the standard said. What is an easy oxide? It refers to a substance that is easy to chemically react with oxygen in a normal environment. For example, iron, aluminum, copper, etc., common and easy to understand is easy to rust metal. However, in the medical industry, it refers to many kinds of substances that are easy to oxidize with oxygen. Organic matter, metal powder, reducing agent, sulfur, phosphorus and other combustibles, human cells and cell membranes and fatty acids are all easy oxides. The easy oxide content of packaging materials is the main technical standard of the country. Medical PVC plastic is usually used for disposable blood transfusion (liquid) equipment, oxygen suction tube, catheter, oxygen mask and other products and medical equipment accessories. At the same time, because of the ideal transparency and appropriate cost, pharmaceutical PVC packaging sheet also occupies a large share in the field of pharmaceutical packaging materials. Because PVC is a heat-sensitive plastic, in the formulation of production generally add heat stabilizers, lubricants, enhancers or modifiers and many other raw materials, 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 raw material oxides added, poor stability in later use, and influence of storage conditions. The main reason is that metal atoms or molecules dissociate or fall off during the formula production process, and react with oxygen to lead to the survival of 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 group effect with the hydrogen that falls off polyvinyl chloride. Many enterprises say that the use of this raw material is still easy. Oxides exceed the standard, so the purity of the raw materials needs to be studied.

Industrial production of PVC heating to about 100 degrees Celsius will occur when the HCL reaction, of course, in the usual thermoplastic processing temperature, PVC in addition to HCL, but also the material color will continue to deepen until the blackening phenomenon, the physical and mechanical properties of the product will continue to decline until the loss of use value. Therefore, it is necessary to add a heat stabilizer for thermal degradation during thermoplastic processing. The thermal degradation of PVC has the following important kinetic characteristics: 1: the degradation rate is related to the actual structure of PVC polymer chain, the type and amount of plasticizer; 2: The degradation rate accelerates rapidly with the increase of temperature; 3: The degradation product HCL has a promoting effect on the degradation itself and is an autocatalytic reaction process; 4: Oxygen or air will accelerate the degradation; 5: metal ions, especially Fe3 ,Zn2 ,Cd2 and other metal ions with Lewis acid properties have a strong role in promoting the degradation of PVC. At present, a large number of PVC stabilizers are used in soft or semi-rigid formulations containing light calcium carbonate, but in less than a month, different degrees of reddening will occur. This is a common problem of most PVC stabilizers at home and abroad. Therefore, when choosing PVC stabilizers, you must be cautious and pay attention to observation. PVC products commonly used in the production of heat stabilizers mainly have several categories, generally non-transparent products to lead salt, supplemented by calcium soap, cheap is the main reason for the use. However, lead is toxic, harmful to the human body, will accumulate in the human body, is not easy to discharge, and will affect future generations; lead can damage the human nervous system, its harm is irreversible, any treatment can not make the dead nerve resurrection, children's sensitivity to damage. Therefore, considering the long-term interests of mankind, it should be gradually reduced to no longer use lead PVC stabilizers, and relevant regulations have been made abroad. Transparent PVC products generally use calcium zinc stabilizer, barium zinc stabilizer, the price is higher than the lead salt, and CaSt2 is still a toxic substance. Transparent and harmless PVC products, such as rigid PVC transparent sheets for food packaging, use organotin as the main PVC stabilizer, its price is high, and organotin itself will bring greater pollution in the production process.

It was found that the lead salt stabilizer blended with other additives would react and generate complex phosphate with very small solubility, thus making the lead precipitation of the lead salt stabilization system significantly reduced. For example, dibasic phosphate is a widely used in PVC and other plastics and, as an absorbent of HCL, the reactant is mainly dichloro derivative, when an additive is added to the dibasic lead phosphate, the product of the chlorination reaction can be converted into a complex extremely insoluble salt. This stabilizer has been entered by the US Environmental Protection Agency into the lead salt stabilizer for toxicity purposes, and some other lead salts can also be modified by this method. This kind of lead salt stabilizer has the characteristics of low solubility, low precipitation and low migration, and when it is blended with polymer, the above performance is better. However, in view of the fact that lead salt stabilizers do have toxicity, efforts are being made to develop such stabilizers with lower precipitability. In addition, the use of dust-free composite lead salt stabilizers has an increasing trend, which provides convenience for PVC processing enterprises and reduces lead salt dust pollution in processing enterprises. Looking back on the market in recent years, the development of heat stabilizers is very fast, and there are the following trends in general: 1: Improve stabilization efficiency Improving the stabilization efficiency can not only prolong the service life of the product, but also improve the high temperature processability and reduce the amount of PVC stabilizer added. Especially in the development of some environmentally friendly stabilizers, new organic auxiliary stabilizers, such as phosphites, will be developed. It has excellent who solubility for polyolefins, polyesters and polycarbonates. In addition, it is necessary to improve the compounding technology and develop the compounding technology of weather-resistant additives and light stabilizers. Development of metal-free stabilizers to reduce the use of metal soaps, especially zinc soaps. 2: Reduce costs Improving the stability efficiency can undoubtedly reduce the cost, but people are still working hard to centralize and automate the production and develop a new variety of multi-functional PVC stabilizers to reduce the cost. At the same time, we should make full use of cheap raw materials. Such as the development of antimony stabilizer instead of tin stabilizer, because of its excellent heat resistance, only a small amount of mixing can obtain better heat resistance than tin stabilizer. Its single disadvantage is poor weather resistance. This needs to be overcome. At present, the sales of antimony products are increasing. Rare earth PVC stabilizers are a rookie in the world's stabilizer series, non-toxic, with good light and thermal stability. I have a very rich rare earth resources, should strengthen the research in this area. The research and development of composite rare earth PVC stabilizer is much better than a single component, and has broad application prospects.