News Details
Antioxidant of organic materials
2018-1-2 20:55:45
Antioxidant of organic materials
All organic materials have atmospheric oxidation, and synthetic polymers are particularly sensitive to oxidative degradation. To prevent their atmospheric oxidation is very important for many commonly used materials such as rubber, plastic, fiber, lubricating oil and petroleum products.
The oxidation of edible oils and foodstuffs not only destroys their nutritional value, but also produces unpleasant odors and harmful peroxides. When people eat these oxidized foods, they will cause illness. Therefore, it is crucial to prevent the desired oxidation of the above substances.
There are many ways to prevent the oxidation of organic matter, but the addition of organic material antioxidant is an effective and most convenient method. Because of this addition, there is no need to change the existing production process. At the same time, there are many effective antioxidants for organic materials.
The so-called antioxidant (Antioxidant) refers to those compounds that can prevent or inhibit the oxidation of organic materials. In early 1870, Bogge was first used to naphthylamine and aniline as antidegradants rubber products (Antidegrader), and the service life of the rubber was greatly improved. Obviously, these two compounds are today's aromatic amine antioxidants.
Moureon first proposed antioxidant (Antioxidant) in 1920, and it was used as an antioxidant in industrial scale.
It began in 1921. Due to the rapid development of polymer industry in recent years, the antioxidants in organic materials have been greatly developed.
In the chain automatic oxidation growth reaction, the alkyl peroxyl (ROO) in the polymer increases the reaction chain by reacting the hydrogen. Therefore, the hydrogen is more active than the hydrogen in the polymer, and the compounds that produce stable radicals after the reaction can be used as chain terminators. The typical compounds of these antioxidants are phenols and aromatic amines.
Triphenyl phosphite (TPPi antioxidants, stabilizer) is mainly used in PVC, polyethylene, polypropylene, polystyrene, polyester, abs resin, epoxy resin, synthetic rubber antioxidant stabilizer, used in polyvinyl chloride (PVC) products as a chelating agent.
Cas no. : 101-02-0
HS: 29209019.00
The most important index of products: colorless, yellow liquid
Density (rho) 2525:1.183-1.192, refractive index (eta 020) : 1.585 1.590, freezing point ° C: 19-24, chloride (Cl - %) : 0.20 or less
Tax refund: the current tax refund of Triphenyl phosphite is 9 percent
Raw materials: phenol, phosphorus trichloride, phosphorus trichloride.
In the field of plastics, the main use of phenolic compounds as chain terminator. Its role is to capture free radicals centered on oxygen atoms, such as ROO, HO and RO, and the latter, because of its high activity, can rapidly transform O2 into ROO under oxygen enrichment. The main mechanisms include:
(1) chain termination mechanism
The antioxidant can capture 1~2 peroxisome radicals. The higher the stability of the transition state A and the phenoxy free radical B, the better the effect of the chain terminator. Therefore, the replacement position on the benzene ring is best for the power supply basis, and from the stability of the free radical, there must be a certain spatial steric resistance in the neighborhood. In 2, 6- butylated hydroxytoluene (BHT) as an example, benzene oxygen free radicals in the process of preventing oxidation in further reaction to form various compounds. These oxidation products can cause adverse effects on plastic coloring.
Benzene oxygen free radical (1) free radical coupling reaction will make its capture in stoichiometric reach two. Oxidation products (2) can be decomposed into free radicals at the temperature of 160 C and play the role of chain initiator, so it is very important to turn them into harmless products when preventing high temperature oxidation.
(2) mechanism of chain terminating receptor
Alkyl radicals are added to stabilizers, mainly because alkyl radicals can not effectively extract hydrogen atoms from stabilizers, such as aromatic nitro and nitroso compounds. In the presence of oxygen, alkyl radicals and quinone compounds and stable free radicals (nitroxyl radical) reaction of no importance, because the alkyl radical is quickly converted to peroxylradicals. Only under the condition of dilute oxygen, such as in the extruder, these reactions are of importance and may even play a leading role.
(3) new chain terminating antioxidant
It is important to stabilize the alkyl radical under the condition of dilute oxygen, while the traditional chain free radical terminated antioxidant can not act as a capture of the alkyl radical. In recent years, a new type of antioxidant has been developed. Its mechanism is based on the so-called "pull and push effect", which is characterized by the capture of two macromolecular free radicals. The first step is to serve as a hydrogen donor, and the second step is to combine with macromolecule free radicals.
Metal ions as harmful impurities always exist in polymers and organic materials. They are introduced into the above materials during the process of synthesis, processing, packaging, storing and using. Some metal ions accelerate the decomposition of free radicals of hydrogen peroxide by single electron oxidation and reduction reaction, thus accelerating the self oxidation of materials.
Especially valence metal such as Cu, Fe, Ni, Co, Ti, Cr etc. are easier to promote self oxidation material. Therefore, the reduction of the activity of metal ions can effectively protect the oxidation of polymer organic materials.
The method is to complex the harmful metal ions, reduce the catalytic oxidation activity of these ions, and make the polymer organic materials free from oxidation. For example, the organic compounds of oxime are often used as complexing agents for copper ions, which can effectively prevent the thermal oxidation of cables and wires, and their oxygen resistance is equivalent to that of blocked phenols.
Copyright: Zhang Jia Gang YaRui Chemical co.,Ltd
http://www.yaruichem.com
All organic materials have atmospheric oxidation, and synthetic polymers are particularly sensitive to oxidative degradation. To prevent their atmospheric oxidation is very important for many commonly used materials such as rubber, plastic, fiber, lubricating oil and petroleum products.
The oxidation of edible oils and foodstuffs not only destroys their nutritional value, but also produces unpleasant odors and harmful peroxides. When people eat these oxidized foods, they will cause illness. Therefore, it is crucial to prevent the desired oxidation of the above substances.
There are many ways to prevent the oxidation of organic matter, but the addition of organic material antioxidant is an effective and most convenient method. Because of this addition, there is no need to change the existing production process. At the same time, there are many effective antioxidants for organic materials.
The so-called antioxidant (Antioxidant) refers to those compounds that can prevent or inhibit the oxidation of organic materials. In early 1870, Bogge was first used to naphthylamine and aniline as antidegradants rubber products (Antidegrader), and the service life of the rubber was greatly improved. Obviously, these two compounds are today's aromatic amine antioxidants.
Moureon first proposed antioxidant (Antioxidant) in 1920, and it was used as an antioxidant in industrial scale.
It began in 1921. Due to the rapid development of polymer industry in recent years, the antioxidants in organic materials have been greatly developed.
In the chain automatic oxidation growth reaction, the alkyl peroxyl (ROO) in the polymer increases the reaction chain by reacting the hydrogen. Therefore, the hydrogen is more active than the hydrogen in the polymer, and the compounds that produce stable radicals after the reaction can be used as chain terminators. The typical compounds of these antioxidants are phenols and aromatic amines.
Triphenyl phosphite (TPPi antioxidants, stabilizer) is mainly used in PVC, polyethylene, polypropylene, polystyrene, polyester, abs resin, epoxy resin, synthetic rubber antioxidant stabilizer, used in polyvinyl chloride (PVC) products as a chelating agent.
Cas no. : 101-02-0
HS: 29209019.00
The most important index of products: colorless, yellow liquid
Density (rho) 2525:1.183-1.192, refractive index (eta 020) : 1.585 1.590, freezing point ° C: 19-24, chloride (Cl - %) : 0.20 or less
Tax refund: the current tax refund of Triphenyl phosphite is 9 percent
Raw materials: phenol, phosphorus trichloride, phosphorus trichloride.
In the field of plastics, the main use of phenolic compounds as chain terminator. Its role is to capture free radicals centered on oxygen atoms, such as ROO, HO and RO, and the latter, because of its high activity, can rapidly transform O2 into ROO under oxygen enrichment. The main mechanisms include:
(1) chain termination mechanism
The antioxidant can capture 1~2 peroxisome radicals. The higher the stability of the transition state A and the phenoxy free radical B, the better the effect of the chain terminator. Therefore, the replacement position on the benzene ring is best for the power supply basis, and from the stability of the free radical, there must be a certain spatial steric resistance in the neighborhood. In 2, 6- butylated hydroxytoluene (BHT) as an example, benzene oxygen free radicals in the process of preventing oxidation in further reaction to form various compounds. These oxidation products can cause adverse effects on plastic coloring.
Benzene oxygen free radical (1) free radical coupling reaction will make its capture in stoichiometric reach two. Oxidation products (2) can be decomposed into free radicals at the temperature of 160 C and play the role of chain initiator, so it is very important to turn them into harmless products when preventing high temperature oxidation.
(2) mechanism of chain terminating receptor
Alkyl radicals are added to stabilizers, mainly because alkyl radicals can not effectively extract hydrogen atoms from stabilizers, such as aromatic nitro and nitroso compounds. In the presence of oxygen, alkyl radicals and quinone compounds and stable free radicals (nitroxyl radical) reaction of no importance, because the alkyl radical is quickly converted to peroxylradicals. Only under the condition of dilute oxygen, such as in the extruder, these reactions are of importance and may even play a leading role.
(3) new chain terminating antioxidant
It is important to stabilize the alkyl radical under the condition of dilute oxygen, while the traditional chain free radical terminated antioxidant can not act as a capture of the alkyl radical. In recent years, a new type of antioxidant has been developed. Its mechanism is based on the so-called "pull and push effect", which is characterized by the capture of two macromolecular free radicals. The first step is to serve as a hydrogen donor, and the second step is to combine with macromolecule free radicals.
Metal ions as harmful impurities always exist in polymers and organic materials. They are introduced into the above materials during the process of synthesis, processing, packaging, storing and using. Some metal ions accelerate the decomposition of free radicals of hydrogen peroxide by single electron oxidation and reduction reaction, thus accelerating the self oxidation of materials.
Especially valence metal such as Cu, Fe, Ni, Co, Ti, Cr etc. are easier to promote self oxidation material. Therefore, the reduction of the activity of metal ions can effectively protect the oxidation of polymer organic materials.
The method is to complex the harmful metal ions, reduce the catalytic oxidation activity of these ions, and make the polymer organic materials free from oxidation. For example, the organic compounds of oxime are often used as complexing agents for copper ions, which can effectively prevent the thermal oxidation of cables and wires, and their oxygen resistance is equivalent to that of blocked phenols.
Copyright: Zhang Jia Gang YaRui Chemical co.,Ltd
http://www.yaruichem.com
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