Standard Injection Molding Machine 1. Injection Molding Machine equipment function Standard Injection Molding Machine,Ce Standard Injection Molding Machine ,Standard Injection Machine,Plastic Injection Machine Ningbo Chenwei Machinery Technology Co.,Ltd , https://www.chenweimachine.com
Green alternative is the inevitable choice
For a long time, plasticizers are mainly o-phthalic products such as DOP (dioctyl phthalate). With the increasing application of these additives in the food and pharmaceutical industries, people are paying more and more attention to its toxicity. The study found that DOP products were found in the lungs when the blood stored in the PVC bags was introduced into the body. In 1982, the authoritative National Cancer Institute conducted a bioassay of the carcinogenicity of DOP. The conclusion is that DOP is a carcinogen of rats and mice and can cause carcinogenicity in livers of carnivores. Since then, DOP toxicity has attracted widespread attention.
Although DOP has caused people to continue to argue about carcinogenesis, due to its potential carcinogenicity, various countries have adopted corresponding restrictions. The United States Environmental Protection Agency has stopped the production of six new phthalate ester products based on the findings of the National Cancer Institute. At present, some of the performances of the main plasticizers produced by domestic companies are particularly hygienic and low in toxicity, and it is difficult to meet environmental protection requirements. The EU and Russia successively discovered the presence of toxic PVC plasticizers in plastic toys imported from China.
DOP and DOA (dioctyl adipate) are all plasticizers widely used in China's polyvinyl chloride food cling film, especially DOP is widely used in food packaging products. Due to the higher production cost of DOA, most domestic PVC cling film manufacturers use DOP and DBP (dibutyl phthalate) as the main plasticizer. When the plastic wrap produced in this way is used in a meat product containing high fat or when it is wrapped in a food in a microwave oven, the plasticizer has more chances of entering the food, which is potentially harmful to human health.
Technological backwardness and restricting development
After several decades of development, the plasticizer industry in China has formed a certain industrial scale. Currently, it is the largest producer and consumer of plasticizers in Asia. In 2007, the production capacity was 2 million tons, and the output was 1.2 million tons. The apparent consumption was It is 1.6 million tons. However, although some of our products also have internationally advanced levels, there is still a large gap compared with developed countries as a whole. The first is that the production scale is small and the industry is big and not strong. There are nearly 700 plasticizer manufacturers in China, and about 75% of normal production is basically 1,000 tons. There are only a handful of companies with more than 10,000 tons of plasticizers. Followed by the lack of own technology, research and development level is weak. Although a certain amount of scientific research and production systems have been established, domestic R&D is still dominated by imitation. Again, the process is relatively aging and the device is running inefficiently. Some of the devices built in the 1970s are still in use today and it is difficult to adapt to the competition in the international plasticizer market.
Taking into account the potential carcinogenic risk of plasticizers, especially DOP, the world has begun to take appropriate measures to limit the use. All countries in the world have accelerated the research and development of non-toxic plasticizer products, especially the basic application research of plastic products with high hygiene requirements. However, in China, plasticizers such as DOP, which have been eliminated or restricted from use abroad, have a large market, and the production companies do not pay enough attention to the development and promotion of non-toxic new plasticizers. Due to the low price, 80% of the plasticizers sold in the domestic market are DOP, DBP, etc.
Nowadays, foreign new plastic additives are emerging in an endless stream, and their functions are increasingly refined. However, few domestic high-end products have appeared in the country, and the industry's technological level lags behind that of developed countries for about 20 years. For example, DBP has been banned by many countries, and China still has mass production; the national standard still lists DOP as one of the plasticizers that can be used for food packaging. On the contrary, the varieties of plasticizers such as citric acid esters, 810 esters, polyesters, trimellitates, and epoxy esters, which are non-toxic, durable, and have a good overall performance, are developing slowly.
Meet the trend to achieve a leap
In recent years, in the rapid development of the plastics industry as a whole, China's plastic additives have also developed, but it is mainly reflected in the increase in volume. Faced with the trend of large-scale production, refinement of product specifications, multi-functionalization, and environmental protection in the global plastics additives industry, China's plastics additives companies should increase the research and development of green plasticizer products from the perspective of sustainable industrial development. We will establish development advantages in terms of industrial scale efficiency, environmental performance, product quality, and added value, and strive to occupy a place in the new round of international market competition.
To this end, scientific research units and production enterprises must strengthen cooperation to solve the problems of small scale, few varieties, backward technology, high consumption quotas, and unstable product quality, and organize joint ventures to reduce production costs and energy consumption; and to strengthen technological research and development and achieve comprehensive utilization. , Continuously develop new varieties to meet individual needs, focusing on the research and development of rare earth plasticizers; accelerating structural adjustment, highlighting environmental protection needs, strengthening the research and development of high-efficiency and low-toxic products, and continuously improving the performance and application of plastic products The field provides a strong support for deeper and broader development of China's plastics industry.
â‘ According to the properties of the raw materials used for the products, the screw forms of different structures suitable for the plasticizing conditions can be selected and replaced.
â‘¡ According to the plasticizing conditions of raw materials for products, there should be a stable heat source for heating.
â‘¢ According to the requirements of the product forming quality, the accuracy of the primary feeding quantity shall be guaranteed.
â‘£ In order to ensure the plasticizing quality of raw materials, the screw should have an adjustable and stable back pressure when working.
⑤ According to the needs of different raw materials for post-melting molding, the injection pressure and melt flow rate required by the process shall be available when injecting molten materials into the mold.
â‘¥ The clamping force of the mold during molding is greater than the expansion force of the molten material injected into the mold cavity.
⑦ Control the cooling and solidification molding speed of the molten material in the mold cavity with appropriate mold temperature.
⑧ The molten material flow channel in the forming mold is smooth, and the mold cavity has a certain release angle. According to the structure and shape of the product, the product ejection device shall be set in the molding mold if necessary.
Functions and characteristics of injection molding machine
2. Characteristics of injection molding products
â‘ Various plastic products with complex shapes can be formed at one time.
â‘¡ The structure and mutual position size of the molded parts can be guaranteed, and the surface quality of the products is good.
â‘¢ The structure shape and size of each part of the product can be different, which can ensure the mutual position of the product and the accuracy requirements of the structure size, and the product can have good assembly interchangeability.
â‘£ Plastic products with metal inserts can be injection molded.
⑤ Injection molded parts can be standardized, normalized and serialized.
â‘¥ The production operation of the injection molding machine is relatively simple, and the adjustment and update of the molding mold are relatively convenient.
⑦ The injection molding machine adopts fully automatic production of plastic products, with high production efficiency.
⑧ The investment in injection molding equipment is relatively large, and the manufacturing cost of molds for molding is relatively high. The process conditions for injection molding of molded products need to be strictly controlled.
Plasticizers: green alternative trend
In recent years, the rapid development of the plastics industry has stimulated plastics additives and other plastics additives to grow at an average annual rate of 10.9%. With the increasing awareness of environmental protection in various countries, pharmaceuticals and food packaging, daily necessities, toys and other plastic products have imposed higher requirements on plasticizers. The replacement of traditional varieties with green and environmentally friendly plasticizers has become a general trend.