Development direction of the hottest PVC heat stab

The development direction of PVC heat stabilizer

nowadays, PVC materials are widely used in telecommunications, chemical industry, packaging and other industries, and a fatal weakness in PVC processing is that its flow temperature is 136 ℃, the decomposition temperature is 140 ℃, and the difference between the two is only 4 ℃, which brings great difficulty to processing. In order to process smoothly, 2-4 parts of heat stabilizer must be added, which is one of the indispensable main additives for PVC processing. In recent years, due to the increase in the amount of PVC materials, the varieties of PVC heat stabilizers are also constantly evolving

1. Types of PVC stabilizers

1.1 lead salt stabilizers

lead salt stabilizers are the earliest heat stabilizers used in PVC, and are still widely used. The main varieties and the most commonly used are: Test Method for mechanical force of building external windows with tribasic lead sulfate gb/t 9158 (8), dibasic lead phosphite and composite lead

lead salt stabilizer has the advantages of good heat resistance, excellent electrical insulation, white pigment performance, high adhesion, good weather resistance and low price. The disadvantages are: the obtained products are opaque, toxic, have initial coloring, are not resistant to vulcanization, and have slightly poor compatibility and dispersion. The lead containing waste water discharged in the production process has a serious impact on the environment. With the development of environmental protection and China's entry into WTO, its production and application are increasingly restricted

1.2 metal soap stabilizer

the performance of metal soap stabilizer depends on the type of metal and acid radical. Among them, cadmium soap is highly toxic, can cause bone pain, and has sulfide pollution. It is strictly stipulated in the toxic acute toxicity management law, environmental protection law, food hygiene law and other laws and regulations, so it is rarely used. Now, ba/zn and ca/zn composite stabilizers are commonly used in soft products

1.3 organotin stabilizer

alkyl tin in organotin is usually methyl, n-butyl, n-octyl and so on. Most of the products produced in Japan are butyl tin, while those produced in Europe are more common. This is a standard non-toxic stabilizer recognized in Europe, while methyl tin is used more in the United States

organotin stabilizers have excellent high-temperature chromaticity stability and long-term dynamic stability. Its non-toxic properties have also been recognized by FDA of the United States, BGA of West Germany, BPF of the United Kingdom, HPA of Japan and other institutions

1.4 organic auxiliary stabilizers are not enough to stabilize the industrial chain.

organic auxiliary stabilizers such as nonyl phosphite are usually used in non-toxic applications approved by the quality administration, which are recognized and advocated by environmental protection and green packaging professionals, said Ramsey hermitz, CEO of Shiloh industries, a metal parts manufacturer in Ohio, the United States

1.5 organic antimony stabilizer

this kind of stabilizer is characterized by high thermal stability efficiency and non-toxic. China has less application in this area, and the United States has developed rapidly in this area

1.6 rare earth stabilizer

rare earth stabilizer is another kind of PVC heat stabilizer newly developed in recent years. It has the characteristics of non-toxic, moderate price, environmental protection, low dosage, good heat stability effect and enhancement, and is more popular in the market

2. Development at home and abroad

2.1 foreign

the composition of PVC heat stabilizers in the United States is relatively reasonable, and toxic (lead salts) stabilizers are less used. The United States is in the forefront of the world in terms of lead-free heat stabilizers. In recent years, the friction force has modified the lead content standard in drinking water from the previous 5 × 10-6 to 1.5 × 10-6, which makes the lead-free problem of PVC water pipes more clear. In Western Europe, the transformation from lead salt stabilizers to organotin stabilizers is faster, but not as good as the United States; The amount of lead salt heat stabilizers in Japan is still on the high side. Although the development of PVC non-toxic stabilizers has been stepped up, no results have been achieved

2.2 domestic

with the widespread application of PVC materials in China, it is expected that the consumption of heat stabilizers in the market will increase significantly. In terms of lead salt stabilizers, we will focus on the development of composite lead salt stabilizer technology, which is a granular material integrating stability, lubricity, processability and reinforcement. This kind of product solves the environmental protection problem of flying dust in PVC processing workshop and the problem of difficult measurement, but it can not fundamentally solve the problem of environmental pollution caused by lead salt

organotin stabilizers have been less produced in China, and composite metal soap stabilizers started late and developed rapidly in China; Rare earth stabilizer is a product developed in China in the 1980s. Because China's rare earth reserves account for 80% of the world's reserves and 70% of the world's industrial output, it promotes the development of rare earth stabilizer. It is non-toxic and environmental friendly, which meets the development requirements of the world today

3. Development direction of heat stabilizers

at present, lead is still the most used stable system. The United States mainly uses organotin system, while Europe believes that tin belongs to heavy metals, and calcium and zinc are becoming the main development direction in Europe. With the strengthening of environmental protection and health awareness, plastic heat stabilizers are developing towards low toxicity, pollution-free and high efficiency

3.1 substitute products of lead and cadmium stabilizers have been launched successively. Lead and cadmium are harmful to environment, ecology and human health. Some industrialized countries and regions have successively formulated relevant laws and regulations to limit lead, cadmium and even barium. The representative products are the environmental friendly calcium zinc system stabilizer of German bear brand company

3.2 multivariate composite "one package" products have become the development trend in the market. It can reduce resource waste and environmental pollution. At present, the representative products in foreign markets include British akcros' interlite series products, etc

3.3 vigorously developing rare earth stabilizers will be a major research and development direction that meets the requirements of environmental protection and conforms to China's national conditions. On the one hand, rare earth stabilizers are non-toxic and efficient, which meet the requirements of processing, labor protection and environmental protection. On the other hand, they can be used in food and drug packaging. Therefore, the development of rare earth stabilizers should be the mainstream direction

in short, with the gradual strengthening of global environmental protection and health awareness, PVC heat stabilizers will develop towards low toxicity, pollution-free, composite and high efficiency

source: China plastic packaging information