Progress in the production of the hottest blowing

Progress in foaming agent production (middle)

ADC foaming agent

China is the world's largest producer and supplier of ADC, with an annual production capacity of 150000 tons, accounting for nearly 50% of the world's total production. From 1995 to 2003, the average annual growth rate of production capacity was about 18%, and there were more than 30 manufacturers in 30 provinces and cities across the country, including Jiangsu Thorpe group, Zhejiang Juhua Group Company, Jiangxi electrochemical plant The annual production capacity of Ningxia electrochemical plant has reached the level of 10000 tons; There are many improvements in production equipment, such as the large-scale and continuous production equipment of sodium hypochlorite; Large scale condensation kettle and oxidation kettle; Use continuous drying process, etc. The consumption structure is about 40% PVC, 35% polyethylene, 12% polypropylene, 5% rubber and 8% others. The annual export volume is tons, and the products are mainly sold to Southeast Asia, Japan, South Korea, Russia and other places

with the development of the plastic industry, a single ADC blowing agent can no longer meet the demand, so there are still many deficiencies in the shipment of modified ADC blowing agents to foreign manufactures. Although the production capacity and process technology of ADC in China have made great progress, hydrazine hydrate synthesized by urea method is still widely used as raw material, which is a waste of resources and serious environmental pollution. In foreign countries, ketone nitrogen method or hydrogen peroxide method is mainly used as raw material for production, and hundreds of products have been developed, and new varieties are still emerging to dominate the market. The modified process basically has no three wastes, less investment, and the added value of modified products is greatly improved, High profits were made. However, only ADC pure products can be produced in China. Please make backup when using them at ordinary times. Only a few manufacturers have developed and produced limited varieties of modified ADC foaming agents, but the output is not high, the performance is unstable, and the scope of application is narrow. It is mainly sold and exported with ADC raw powder to provide primary raw materials to developed countries. Therefore, pollution will be left at home, profits will be sent abroad, and the industry lacks momentum for development

adc product modification is to optimize the gas evolution, particle determination, color and thermal decomposition temperature with large error in the number of torsion cycles recorded in the foaming agent experiment. The main ways are to change certain reaction conditions or add certain additives in the preparation process, refine ADC particles, add additives to ADC raw powder, and mix different types of foaming agents to achieve the modification effect

at present, the main types of modified products are:

◆ particle micronization type: it is mainly to crush and grade the raw powder of foaming agent. At present, ADC particles are coarse and few brands in China, and there are many brands in foreign countries according to different particle sizes to meet the foaming needs of different synthetic materials. (to be continued)