News Details
Thermoplastic anti-oxygen agent
2018-1-17 11:27:03
Thermoplastic anti-oxygen agent
Plastics are aged by the effects of oxygen and heat during processing, storage and use, and thermoplastic antioxidants can prevent this oxidation degradation process.
About 80% of total olefin consumption is used for polyolefins, about 15% for polystyrene and the rest for thermoplastic engineering plastics. Market trends are largely determined by the growth in gm consumption. As a result, the consumption of thermoplastic antioxidants in Asia and Latin America is growing faster than in North America and Europe.
The consumption of thermoplastic antioxidants, which do not take into account the thermal stabilizers used for PVC and the antioxidants of elastomers and rubbers.
About half of the antioxidants used in thermoplastics are phenolic compounds. Organic phosphatides accounted for one-third of the total, and thioesters accounted for about 8%. Aromatic amines are of little importance to the stability of thermoplastic plastics because they tend to exhibit strong decolorization and toxicity.
Principle of antioxidant stability. The oxidative degradation of a polymer is caused by the effects of heat, radiation, mechanical stress (such as shear), or free radicals produced by the combination of these factors. These free radicals react with oxygen to form peroxide free radicals, which take hydrogen atoms from successive polymer chains. An unstable hydrogen peroxide is formed, which is further decomposed into free radicals. This continuous chain reaction led to the degradation of the polymer.
Antioxidants are compounds that can prevent or at least delay this degradation process. As a result, antioxidants are mainly composed of antioxidant agents and auxiliary antioxidants according to their chemical mechanism.
The main antioxidant has reactive hydrogen atoms that can react with free radicals. They're called free radical scavengers. This type of antioxidant includes phenol and aromatic amines of steric hindrance, as well as amines of steric resistance.
The auxiliary antioxidants break down the peroxides to prevent chain branching (hydroperoxides decompose into alkyl and hydroxyl radicals). The most important representatives of this type of antioxidant are organic phosphates or phosphates, and thioesters. The phosphatide plays a role in the melting process and is also known as the processing stabilizer. Thioesters are more of a long-term thermal stabilizer.
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, when is given priority to with metal stabilizer, cooperate with this product can reduce the harm of metal chlorides, maintain product transparency, and inhibition of color change, is also a good chemical intermediates, with phosphorus-containing flame retardant and use, can play a role of flame retardant antioxidant, and with stable performance, light can be used for synthesis alkyd resin and polyester, main raw materials for resin, this product can also be preparing pesticide intermediates trimethyl phosphite.
The two mechanisms can also be incorporated into a single compound. The combination of main antioxidants and auxiliary antioxidants represents the current technological level of many polymer stability. The concentration of antioxidant was 0.03 ~ 0.3% in weight, which varies with the type of plastic, and even more than 1% in special application conditions.
Antioxidants tend to decolorize under the influence of nitrogen oxides. This phenomenon is called gas discoloration in the literature and is a special problem for polypropylene fiber. Decolorization is aggravated by various factors, such as the presence of phenol antioxidant, the type of phenol or the use of alkaline co-additives. Despite years of low decoloration, phenols have been used in this field (for example, ao-5), but the free phenol series is the only effective solution. Fiberstab L112 (FSL) is a series of free phenols specially developed for PP fiber. It is based on the ester hp-136, and hp-136 is used as the processing stabilizer to provide protection during spinning and has the best gas fading characteristics.
The Irgastab FS series (fs-1) is another invention in the field of antioxidants. They are the free phenol series developed for the stability of PP fiber processing during UV protection. They are now widely used in other areas of purpose, such as the stabilizer of PP moulded color car bumpers. In this case the processing stabilizer is hydroxylamine Irgstab Fs042 (ao-10). In addition to good processing stability, it is noteworthy that the PP fiber treated with Irgastab FS can obviously maintain the color color. Since this processing stabilizer can be used in combination with the hindered amine stabilizer (HAS), it is mainly used in situations where UV stability is high.
Ao-10 related compounds are used as antioxidants in PP. The remarkable characteristic of this compound in the form of trialkylamine oxide is its good stabilizing effect and "gas fading" characteristic, similar to all the free phenol series. But there is no detailed information about its industrial application.
The current trend is to continue to develop an alternative mixture of antioxidants and antioxidants and other additives. Special attention is paid to the development of easy to add and high dust free products. In addition to improving industrial hygiene conditions, the possibility of direct addition provides the optimal distribution and reduces the paradoxical drawbacks of the recipe. This enables plastic processors to improve quality and save costs.
Plastic and environmental suitability and recycling of waste plastics, under pressure from the public and the government, are increasing, which affects additive manufacturers. However, it is rare to know the environmental suitability of plastics and the effects of antioxidants. Some long-term studies have begun, and the results have not been reached.
Copyright: Zhang Jia Gang YaRui Chemical co.,Ltd
http://www.yaruichem.com
Plastics are aged by the effects of oxygen and heat during processing, storage and use, and thermoplastic antioxidants can prevent this oxidation degradation process.
About 80% of total olefin consumption is used for polyolefins, about 15% for polystyrene and the rest for thermoplastic engineering plastics. Market trends are largely determined by the growth in gm consumption. As a result, the consumption of thermoplastic antioxidants in Asia and Latin America is growing faster than in North America and Europe.
The consumption of thermoplastic antioxidants, which do not take into account the thermal stabilizers used for PVC and the antioxidants of elastomers and rubbers.
About half of the antioxidants used in thermoplastics are phenolic compounds. Organic phosphatides accounted for one-third of the total, and thioesters accounted for about 8%. Aromatic amines are of little importance to the stability of thermoplastic plastics because they tend to exhibit strong decolorization and toxicity.
Principle of antioxidant stability. The oxidative degradation of a polymer is caused by the effects of heat, radiation, mechanical stress (such as shear), or free radicals produced by the combination of these factors. These free radicals react with oxygen to form peroxide free radicals, which take hydrogen atoms from successive polymer chains. An unstable hydrogen peroxide is formed, which is further decomposed into free radicals. This continuous chain reaction led to the degradation of the polymer.
Antioxidants are compounds that can prevent or at least delay this degradation process. As a result, antioxidants are mainly composed of antioxidant agents and auxiliary antioxidants according to their chemical mechanism.
The main antioxidant has reactive hydrogen atoms that can react with free radicals. They're called free radical scavengers. This type of antioxidant includes phenol and aromatic amines of steric hindrance, as well as amines of steric resistance.
The auxiliary antioxidants break down the peroxides to prevent chain branching (hydroperoxides decompose into alkyl and hydroxyl radicals). The most important representatives of this type of antioxidant are organic phosphates or phosphates, and thioesters. The phosphatide plays a role in the melting process and is also known as the processing stabilizer. Thioesters are more of a long-term thermal stabilizer.
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, when is given priority to with metal stabilizer, cooperate with this product can reduce the harm of metal chlorides, maintain product transparency, and inhibition of color change, is also a good chemical intermediates, with phosphorus-containing flame retardant and use, can play a role of flame retardant antioxidant, and with stable performance, light can be used for synthesis alkyd resin and polyester, main raw materials for resin, this product can also be preparing pesticide intermediates trimethyl phosphite.
The two mechanisms can also be incorporated into a single compound. The combination of main antioxidants and auxiliary antioxidants represents the current technological level of many polymer stability. The concentration of antioxidant was 0.03 ~ 0.3% in weight, which varies with the type of plastic, and even more than 1% in special application conditions.
Antioxidants tend to decolorize under the influence of nitrogen oxides. This phenomenon is called gas discoloration in the literature and is a special problem for polypropylene fiber. Decolorization is aggravated by various factors, such as the presence of phenol antioxidant, the type of phenol or the use of alkaline co-additives. Despite years of low decoloration, phenols have been used in this field (for example, ao-5), but the free phenol series is the only effective solution. Fiberstab L112 (FSL) is a series of free phenols specially developed for PP fiber. It is based on the ester hp-136, and hp-136 is used as the processing stabilizer to provide protection during spinning and has the best gas fading characteristics.
The Irgastab FS series (fs-1) is another invention in the field of antioxidants. They are the free phenol series developed for the stability of PP fiber processing during UV protection. They are now widely used in other areas of purpose, such as the stabilizer of PP moulded color car bumpers. In this case the processing stabilizer is hydroxylamine Irgstab Fs042 (ao-10). In addition to good processing stability, it is noteworthy that the PP fiber treated with Irgastab FS can obviously maintain the color color. Since this processing stabilizer can be used in combination with the hindered amine stabilizer (HAS), it is mainly used in situations where UV stability is high.
Ao-10 related compounds are used as antioxidants in PP. The remarkable characteristic of this compound in the form of trialkylamine oxide is its good stabilizing effect and "gas fading" characteristic, similar to all the free phenol series. But there is no detailed information about its industrial application.
The current trend is to continue to develop an alternative mixture of antioxidants and antioxidants and other additives. Special attention is paid to the development of easy to add and high dust free products. In addition to improving industrial hygiene conditions, the possibility of direct addition provides the optimal distribution and reduces the paradoxical drawbacks of the recipe. This enables plastic processors to improve quality and save costs.
Plastic and environmental suitability and recycling of waste plastics, under pressure from the public and the government, are increasing, which affects additive manufacturers. However, it is rare to know the environmental suitability of plastics and the effects of antioxidants. Some long-term studies have begun, and the results have not been reached.
Copyright: Zhang Jia Gang YaRui Chemical co.,Ltd
http://www.yaruichem.com
Spanish
French
Italian
Portuguese
Japanese
Korean
Arabic
Russian