Shortly before China plastics processing industry association professional committee of plastic pipe lead declaration published banned, will ban lead in PVC pipe, the leading enterprises in the domestic several heat stabilizer of feedback is also very positive, no doubt in the history of the development of environmental protection heat stabilizer in China is of great significance, will push the development of Chinese environmental protection heat stabilizer in the fast lane.

Banned lead long by European PVC heat stabilizer supplier agree on, given that the eu laws and regulations, they promised, in 2010 to halve the amount of PVC heat stabilizer of lead salt, by 2015 without lead salt as stabilizer. Lead salt stabilizers will be replaced by metallic mixtures of calcium and zinc.

China plastic (plastic additives of heat stabilizer branch chairman said: "the plastic pipe industry group signed a declaration of banning lead in PVC pipe, will increase the attention of the whole society to ban lead, environmental protection heat stabilizer market environment will be improved. This provides the opportunity for the thermal stabilizer industry to adjust the product structure, and will accelerate the pace of lead in the thermal stabilizer industry. He analyzes believed that plastic pipe industry test ban lead process may face two aspects: on the one hand, to achieve the requirement of environmental protection standards, product upgrading, will inevitably increase the cost, the PVC pipe industry is such a small profit, there are certain pressure; On the other hand, compared with the lead salt thermal stabilizer, there are still some differences in the stability, application range and price of the existing calcium and zinc composite thermal stabilizer and organic tin thermal stabilizer in China. Thermal stabilizer production enterprises should also accelerate the development of efficient and environmentally friendly new products, and it is necessary to further reduce production costs through technological development.

The competitive advantage and wide application prospect of plastic pipe.

Plastic and traditional materials are different, the pace of technological progress is faster, and new technologies, new materials and new processes that appear constantly make plastic tubes more and more prominent in the traditional materials. Plastic pipe material, in comparison with the traditional metal and cement pipe with light weight, generally only 1/6-1/10 of metal pipe, have good corrosion resistance, impact resistance and tensile strength of the plastic tube surface is larger than that of cast iron pipe is smooth, small friction coefficient, fluid resistance small, can reduce energy consumption of water by more than 5%, good comprehensive energy saving, make right 75% lower energy consumption, convenient transportation, simple installation, the service life of 30 to 50 years. Polyethylene pipes have developed rapidly in the world over the past 10 years, and the developed countries have taken advantage of the application of polyethylene pipe in the field of water supply and gas. Polyethylene pipe is not only used to replace traditional steel pipe, cast iron pipe, but also in place of PVC pipe, the reason is that in the past 10 years, polyethylene pipe technology innovation. On the one hand, material has made great progress. Through the improvement of polyethylene polymerization process, the strength of the special materials for PE pipe has almost doubled. Application technology has a new development on the other hand, such as pipeline without excavation in recent years, with directional drilling method of polyethylene pipe laid technology give full play to the superiority of the polyethylene pipe, make the traditional pipe is suitable for the occasion of this way there is no ability to compete.

Building plastic application ratio requirements: in 2005, in the engineering of a building, rebuilding and expansion of plastic pipe ratio for: construction of drainage pipe by more than 70%, building water supply and hot water supply by more than 60%, wire casing by more than 80%, construction of rainwater drainage by more than 50%, rural water supply pipeline by more than 70%, urban drainage pipe by more than 30%, city gas pipeline (low pressure pipe) in more than 50%. Therefore, about 760,000 tons of UPVC pipes and pipes are required. LDPE and H/MDPE pipes, pipe pieces 160,000 tons. In 2010, the proportion of plastic pipes used in the construction, reconstruction and expansion of the construction was: 85% of the building drainage pipes, and the traditional cast iron pipes were eliminated. More than 85% of architectural water supply, hot water heating of the low echo, wire casing by more than 90%, construction of rainwater drainage by more than 80%, urban water supply pipe (DN400 mm) more than 80%, rural water supply pipeline by more than 85%, urban drainage pipe by more than 50%, city gas pipeline (low pressure pipe) in more than 60%. National building in engineering, architectural water supply pipe, drainage pipe, wire casing protector, urban water supply pipe (DN400 mm below), the urban drainage pipeline, city gas pipeline (such as low pressure pipe) in the scope of application of penetration to reach more than 90%.

Classification and development of thermal stabilizer.

In 2007, the total production of thermal stabilizer in China was about 340,000 t, up 9.3% year on year. Lead salt production decreased by 10,000 t, and the yield of calcium/zinc composite stabilizer increased rapidly, and its yield and apparent consumption increased by 50% and 33% respectively. Lead salt production increased damping, dust-free composite lead salt in 2008 began to decline, calcium/zinc compound stabilizer a doubling of capacity, output, production of china-craze stabilizer had speed rapid growth, 10% ~ 15% a year on average in 2008 to produce about 2008 tons of heat stabilizer.

1. Lead salt and dust - free composite lead salt heat stabilizer.

Lead salt heat stabilizers, 20th year 50 generations of successful development, has occupied the main position, the current production capacity of 140000 tons/year, alkali type lead sulfate production in China is the largest, alkali type phosphite lead less, few varieties of lead salts in production. Dust-free composite production of lead salt increased sharply in recent years, some lead salt factory reconstruction or expansion into dust-free composite lead salts, but also the new established a dust-free composite lead salts of small businesses, quality and production are basically meet the production requirements, but not the relevant quality standards, the enterprise product quality difference is bigger. At home and abroad in 2007 because of banned lead, lead prices soared, lead and its products transportation is restricted, so production fell dramatically in 2007, 2008 to 50 kt (another 40 kt was used to prepare other low lead stabilizers is excluded).

2. Rare earth compound stabilizer.

Extremely rich rare earth resource in our country, make full use of rare earth resources is our responsibility, benefit the people there are 17 kinds of rare earth elements, but the only two elements lanthanum, cerium can be used in PVC heat stabilizer, they are non-toxic, transparent, no radiation, and has unique coupling, lanthanum, cerium, the electronic structure of two kinds of elements can be accept 6 to 12 ligand lone electron pair and complexing key, it can inhibit the PVC HCl reaction. Rare earth compound stabilizer also has the enhancement function, the weatherability, the insulation excellent, has the toughening, the enhancement effect. However, at present, the domestic rare earth compound stabilizer is basically based on lead salt, and therefore does not meet the hygienic requirements. In recent years, we have been studying low-lead rare earth composite stabilizers, and companies such as weilinna and guangyang have announced the development of lead-free, non-toxic sanitary grade rare earth compound stabilizers and have been exported abroad. Since rare earth stabilizer is a technology developed by our country, in order to promote the healthy development of the industry, the industry standard should be set up in time to protect the quality products.

In the future, the task is to achieve lead-free, high efficiency and cost reduction. To do well in the complex technology, fully develop the characteristics of rare earth elements and make the rare earth complex thermal stabilizer based on the world. Use of rare earth elements of the strong coordination ability, to replace it with N - phenyl maleic imide, N - alkyl maleic imide reaction preparation of maleic imide rare earth complex heat stabilizer, through the test, it is similar to the long-term thermal stability of organic tin, in use process will suddenly become black, this is the direction of the development of non-toxic utilizing rare earth complex heat stabilizer, rare earth calcium/zinc compound heat stabilizer is also worth the attention of the development direction.

3. Metal soap calcium/zinc composite thermal stabilizer.

Metal soap calcium/zinc composite stabilizer is divided into two kinds of solid powder and liquid, and there are many production enterprises, mainly shenzhen zhihai industrial co., LTD., which was built in early 2006. Hebei hengshui jingxin chemical group was completed in 2008 with 30,000 t/a devices. It is worth mentioning, hangzhou new plastic additives research co., LTD. And hangzhou trilobites chemical co., LTD., the development of high efficiency liquid calcium zinc complex stabilizer, the cable industry application and authoritative test department test proved that conform to the RoHS and WEEE directive, and the volume resistivity of 1.0 x 1012 Ω cm, solved the problem in the cable industry for a long time, will be 5000 t/a liquid compound calcium/zinc stabilizer device. Current production technology of calcium zinc complex stabilizer was still in the stage of development, although there are quite a few units can claim to have the production, and export, but is limited after all, product quality stability and thermal stability there is still a gap compared with international famous brand. Diketone (mainly stearoyl - benzoyl - methane and methylene benzoyl) is not in calcium zinc complex stabilizer and lack of variety, burning it to improve the thermal stability, inhibition of zinc and light stability plays an important role, but the price is expensive, and therefore many factories use it, for the general soft products may be, but there is a risk for cable insulation material; It is dangerous for hard products, especially transparent films and profiles. Shanxi chemical research institute, clam port thermoelectric co., LTD and other units have produced.

Calcium/zinc compound stabilizer is a ideal environmental protection heat stabilizer, should concentrate on research the best compound formula and improve the preparation technology and raw materials to force based on domestic, for products USES and processing equipment to produce special brand, whether solid, liquid or cream, formulate industry standards. Today's main direction is to find the best distribution of compounds, such as cyclohexanol glycidyl ether glycol (2) to calcium zinc complex stabilizer system has a good synergy, it can effectively control the phenomenon of zinc to burn.

4. Organic tin stabilizer.

The use of organic tin thermal stabilizer is 0.25% ~ 0.45%, compared with 1.5% ~ 2.5% in China. In addition to improving the production process, we should also carry out the research of the complex technology, meanwhile, we should improve the thermal stability efficiency, reduce the amount of adding in PVC to reduce the production cost, and achieve high efficiency and low price. Organic tin, antimony heat stabilizer is efficient, low toxicity, transparency, good initial color, less dosage, relatively competitive in price, methyl mercaptan, ester base mercaptan tin tin and other domestic has formed productivity; The performance of organic antimony is similar to organic tin, and the price is low, so there is room for development.

5. Hydrotalcite thermal stabilizer.

Hydrotalcite (HT) compounds anionic layered materials, is a double hydroxyl compound metal oxides, is a novel plastic additives, has widely applied in the plastic film, as an anti-reflection, slow release, heat preservation sex additives. As heat stabilizer, its thermal stability than barium soap, calcium soap and their mixture is good, no sulfur pollution, non-toxic, corrosion of equipment, will not have transparency, good insulation, weather resistance and processability of advantages, will have synergy with zinc soap. Hydrotalcite heat stabilizers and organic tin, zinc, calcium salt and so on have synergy, Shared with other additives can improve the light stability, flame retardancy, weather have self lubrication, also can improve the heat preservation of thin film. It is a new kind of thermal stabilizer which is worth developing. There have been a number of research institutions in the in-depth study, hope to enter the production application phase as soon as possible.

6. Zinc base non-toxic heat stabilizer.

Zinc-base non-toxic stabilizers mainly adopts the stearic acid, lauric acid, quantitative analysis, such as the naphthenic acid, benzoic acid, zinc salt as the main heat stabilizer, such as amino acid organic compound zinc salt of alternative, inhibits zinc to burn, the distribution of content will have a higher thermal stability. It must be used with a variety of synergistic stabilizers, such as beta - diketone, and - aminosuccinate.

7. Common stabilizer

The stabilizer is a class of compounds that do not have a stabilizing effect, but with other thermal stabilizers, they can significantly improve the stability effect. Commonly used with phosphite ester, epoxy plasticizer, polyol, phenolic antioxidants, diketone, hydrogenated which the organism derivatives, beta ketone carboxylic acid ester, maleic imide nitrogenous organic compounds, such as water talc, zeolite, perchlorate potassium, alkali type calcium phosphate inorganic compounds such as aluminum. In the future, the compatibility research of such common stabilizers should be strengthened.

8. Lamellar dihydroxy complex metal hydroxide (LDHs)

The chemical general formula of LDHs is: M2+1-XM3+X(OH) an-x /nmH2O, in which: M2+, M3+ is metal cation; An- is a slight anion in the interlayer; 0.2 x 0.33 or less or less; The m value can be calculated by m=1-NX/n. (N is the number of positions occupied by anions, and N is the charge of anions. LDHs can absorb the HCl released by PVC pyrolysis because of the alkaline surface of its laminate surface, and the CO32- can be used for ion exchange with Cl- to absorb HCl and inhibit the effect of PVC. A non-toxic thermal stabilizer with excellent thermal stability can be obtained by introducing functional elements and groups with thermal stability into laminates and layers.

It remains to be seen who can take the lead in the post-development era of environmental heat stabilizers.