PVC compound stabilizer

Pure PVC resin is extremely sensitive to heat, when the heating temperature reaches 90Y: more, the thermal decomposition occurs slight reaction when the reaction temperature rose to 120C after decomposition intensified in 150C, 10 分钟, PVC resin, the original white gradually turns yellow - red

- Brown - black. PVC resin decomposition process is due to de-HCL reaction caused a chain reaction leading to macromolecules strand breaks. Prevent the thermal stability of PVC thermal decomposition mechanism is through the following aspects to achieve.
(1) by thermal decomposition of PVC capture HCl, to prevent degradation of the catalytic HCl. Click mechanisms lead salt major role, in addition to metal soap, organic tin, pho sphorous and other lipids and epoxy.
(2) replacement of reactive allylic chlorine atom. Metal soap, phosphorous lipids and organic tin can click here Mechanism effect.
(3) react with free radicals to terminate radical reactions. Organic tin and phosphorous mechanism of lipid Click role.
(4) and conjugated double bond, inhibiting the growth of conjugated chain. Organotin mechanism with epoxy Click role.
(5) peroxide decomposition, reducing the number of free radicals. Organic tin and phosphite Click Mechanism effect.
(6) de HCl passivating effect of a catalytic metal ions.
   With a stabilizer according to several different mechanisms for thermal stability purposes.
   Heat stabilizers Varieties - composite stabilizer
   Composite stabilizer can be divided into the following categories:
1 Liquid Ba-Zn composite stabilizer are generally pale yellow to yellow-brown oily liquid, specific gravity of 1.0-1. 1 at room temperature, good heat resistance, pollution from sulfur, with an epoxy plasticizer and used to increase the stabilizing effect, it activation of the blowing agent.
2 liquid calcium zinc composite stabilizer nontoxic liquid calcium zinc stabilizers main ingredients are calcium stearate, castor oil, calcium, zinc stearate, castor oil, zinc and epoxy soybean oil, ultraviolet absorber. Hugh liquid calcium zinc stabilizers are generally used more soluble in organic

Solvent is an aliphatic carbon number of less fat calcium and zinc. Because of different compositions, varied in nature, usually pale yellow to yellow clear oily liquid at room temperature under a specific gravity of 1.0 to 1.05. It is non-toxic PVC stabilizer , mainly used for food packaging films, containers bubble people

Artificial leather stabilizer.
3. Liquid and liquid barium cadmium, barium cadmium zinc composite stabilizer, such composite stabilizer is mainly used for the processing of soft PVC products, the basic components include: (a) barium salt - can be alkylphenols barium, 2 - ethylhexanoic acid, barium, barium laurate (powder lamination), benzoic acid and substituted

Benzoic acid, barium and barium neodecanoate. Barium salt complexes accounted for 6-7%, ie cadmium salts ratio is around 2:1-32 (with metal in mind that weight percent, the same below). (2) cadmium salts - can be 2 - ethylhexanoic acid cadmium, cadmium lauric acid, oleic acid cadmium, phenyl and substituted benzoic acid

Cadmium, cadmium naphthenate, neodecanoate, and cadmium. Cadmium salt complexes about 3-4%. (3) zinc - can be 2 - ethylhexyl zinc, zinc laurate (powder lamination), zinc naphthenate, zinc neodecanoate, benzoic acid and substituted benzoic acid and zinc. Accounts for the composite zinc

0.5-1%. (4) phosphite - may be triphenyl phosphite, diphenyl phosphite, an octyl diphenyl phosphite, a decyl phosphite, tris (nonylphenyl), etc. In the phosphite complexes about 15-20% (by weight), as a chelating agent. (5) Other - including a small amount of

2,6 - t-butyl-p-cresol, bisphenol A, nonylphenol and other phenolic antioxidants and ultraviolet absorbers, and a liquid paraffin, white oil, diesel oil, mineral oil, spindle oil as solvent, and the need Add a small amount of antifoaming agent such as higher alcohols.
   Liquid barium cadmium zinc composite stabilizer because different composition, properties are also different. But is generally pale yellow to yellow clear liquid, specific gravity 0.95-1.02 at room temperature, the viscosity of less than 100 cps, freezing point at -15 ℃ or so. Liquid barium cadmium and liquid barium cadmium zinc are similar to each

Excellent thermal, light stability, initial coloration is small, good transparency and color stability. Their stabilizing effect than solid composit e soaps, therefore, may reduce the amount of, usually 2-3 parts, the dust does not occur poisoning, and completely dissolved in the plasticizer generally have

Good dispersion, the precipitation tendency of small. Wherein the liquid barium cadmium zinc early color than the liquid barium cadmium smaller.
4 lead salt composite stabilizer good thermal stability, has been widely used, but small lead salt powder, ingredients and mixed in its dust is inhaled can cause lead poisoning, for which they have developed a new type of scientific and technical personnel The composite lead salt heat stabilizer. This compound additive

Reaction technique using a symbiosis of the three salts, di-salt and the metal soap in the reaction system in the nascent grain size and various lubricants be mixed to ensure the PVC heat stabilizer system in the fully dispersed, and because of the lubricating agent of melting gr anular, but also to avoid

A result of lead poisoning caused by dust. Inclusive of lead salt stabilizer compound required processing heat stabilizer component and a lubricant component, known as a full package heat stabilizer. It has the following advantages: (1) compound heat stabilizer various components can be obtained in the course of production

Sufficiently mixed with the resins greatly improved the uniformity of dispersion. (2) mixing formula, simplified measurement frequency, to reduce the probability and the resulting measurement error caused by the loss. (3) a simple supply and reserve materials, is conducive to production and quality management.

(4) provides the possibility of clean production of products, improving production conditions.
    Composite stabilizer security issues
    PVC compound stabilizer security issue has been more and more people s attention. PVC compound stabilizer securit y should be three aspects to consider, first, the safety of using the processing of raw materials, the second is the user s security and the third is the safety of waste on the environment. Plus

Workers safety protection may be liquefied by stabilizing agent, paste technology, granulation and other measures to solve them. , Security protection for the user, can be prepared by a stabilizer or a reactive high molecular weight stabilizers to improve its resistance to pumping, but taking into account the effect of stabilizing the molecule

Class of chemical reactions, the above method is not the most appropriate method, the best method is still used high-security stabilizers. Stabilizer is selected, the stabilization process must also be considered in the resin and stabilizing agent, or stabilizers react with each other chemicals generated

Security.
From a variety of security stabilizers see, cadmium stabilizers in the near future will be di scontinued. But a slow process, one of the reasons is that most in the use of cadmium stabilizers when costs are increased by 10% -20%, and cadmium-based stabilizers can not be common to a wide range

The PVC compound. Such as processing a narrow range, but also often need to use auxiliary stabilizer compensate for its performance deficiencies. Now cadmium stabilizers performance has reached a performance of cadmium stabilizers. Calcium zinc stabilizers have been developed rapidly. And in powder, paste and liquid, and

Standard and non-toxic level for sale, second-generation calcium zinc stabilizer in food and pharmaceutical packaging has been replaced by methyl tin tin and zinc base.
Lead stabilizers set its extraction resistance is small, so the use of security when not a problem, but there are security issues harm the environment. Because lead-based stabilizers, low cost, high efficiency, many companies are using this, along with non-lead PVC comp ound stabilizer development, lead salts being no

Environmental toxicity replaced stabilizer. As many countries ban lead, lead-based stabilizers are withdrawn from the market
In short, the composite heat stabilizer help scale production, lead salt heat stabilizer for the development of a new direction. Lead salt stabilizer compound is an important indicator of lead content, current production of lead lead salt stabilizer compound is generally 20% -60%; in PVC plastic door

Window profile production on the amount of 3.5-6 parts