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PVC (polyvinyl chloride) plasticizer
2017-12-25 10:56:52
PVC (polyvinyl chloride) plasticizer
The plasticizing mechanism of PVC (polyvinyl chloride) plasticizer is introduced in this paper. The selection method of PVC (polyvinyl chloride) plasticizer was analyzed.
Plasticizer is a material added to materials (usually plastics, resins or elastomers) to improve their workability, plasticity, flexibility and tensile properties, but they will not change the basic chemical properties of plasticized materials. It is mainly applied to polyvinyl chloride (PVC) resin. The amount of PVC can account for more than 98% of the total plasticizer consumption. Therefore, the development of plasticizer is closely related to the development of PVC industry.
The research and development of plasticizer for PVC (PVC) is focused on developing and producing more plasticizers with high performance, functionalization, innocuity and specialization, and further improving the production process.
The plasticizing mechanism of PVC (polyvinyl chloride) plasticizer. Plasticizer modified PVC has two main functions: one is to reduce the melting temperature and melt viscosity of PVC, thereby reducing its processing temperature; the other is to give PVC products softness, elasticity and low temperature resistance.
Plasticizers can be divided into two kinds of plasticizers and external plasticizers according to their principle and mode of action. The internal plasticizer changes the structure of PVC by chemical method so as to achieve the plasticizing effect. The advantage of internal plasticization is that the soft and hard segments have stable chemical bonding, and there is no disadvantage of loss of migration and volatilization. The disadvantage is that internal plasticization has some limitations on chemical modification of PVC resin, technically or economically.
External plasticizers are usually highly volatile high boiling esters. A few of them are low melting point solids. They generally do not react with PVC. Their plasticizing effect is achieved by coupling and shielding effects of plasticizers on PVC resin.
The coupling effect is the interaction between polar groups of plasticizer and polar group of PVC resin instead of polar connection between the original polymer molecules. Generally, the former force is weaker than the latter, which reduces the secondary valence of polymer. In addition, the polar parts of polar plasticizers still have the function of shielding the polar group of PVC, which can make the polar groups of neighboring polymer molecules not act, but also reduce the intermolecular force and increase plasticity.
The selection of plasticizers. When the plasticizer is used in the formula, its compatibility and plasticizing efficiency are the factors that should be taken into consideration in the PVC plasticizer.
The compatibility of plasticizers also adapts to the principle of "similarity and consistency". Plasticizers are physically bound by physical forces rather than chemical forces (chemical bonds). Therefore, the more the solubility parameter of the plasticizer is closer to the solubility parameter of the resin, the better the compatibility of the two.
Physical and chemical properties of two octyl terephthalate (plasticizer DOTP)
Appearance: transparent and colorless liquid
Boiling point: 400 degrees centigrade
Density: 0.984
Melting point: 30-34 degrees centigrade
Flash point: 238 degrees centigrade
Refractive index: 1.489-1.491
Flash point centigrade 210
Water is less than or equal to 0.03
Acid value is less than 0.1 mgKOH/g
The refractive index is greater than or equal to 1.4900 (20 C)
Color = (platinum cobalt) 30
The ester content% (chromatography) more than 99.5
Density (20 C) g/cm3 0.981-0.985
Use of two octyl terephthalate (plasticizer DOTP)
1.DOTP has good electrical and thermal properties. It can be used to replace DOP in the sheath of PVC plastic wire and can also be used in the production of artificial leather membrane. In addition, with excellent compatibility, terephthalic acid ester is two PVC acrylonitrile derivatives plastic plasticizer, plasticizer, plasticizer, polyvinyl butyral nitrile rubber plasticizer, plasticizer for cellulose nitrate. The improvement of the product and plays the role of hardness and deformation, can be used as softener in NBR, chloroprene rubber, EPDM rubber and other products three. Especially for cable material, it has good plasticizing effect and low volatility. It is widely used in various products that require heat resistance and high insulation. It is an ideal plasticizer for producing 70 PVC cable material and other volatile resistant products.
2.DOTP is used for the PVC products in the car, which can solve the fog problem of the glass window. DOTP is also used for high quality lubricants or lubricant additives furniture and interior decoration paint, and precision instruments, nitro varnish additives, paper softener, biaxially oriented polyester amide membrane film, plastic bags and other crafts, plasma storage.
3. because the linear molecular structure of DOTP is similar to DOS and DOA, its cold resistance is also better.
The volume resistivity of 4.DOTP is 10-20 times higher than that of DOP, and its mobility is excellent.
5., because DOTP does not contain o-phthalate two formate, it is not an environmental friendly plasticizer in the range of 16 16 kinds of plasticizers containing o-phthalic acid in the European Union and other countries.
Generally speaking, the polarity of plasticizer has the greatest influence on the compatibility. The compatibility between the middle molecules of the same kind is poorer, for example, the compatibility of C4 two C10 esters decreases. Polyol esters have better compatibility than monol esters. Polyester is poor in compatibility because of its large molecular weight.
The dielectric constant is a function of the molecular polarity, which is greatly influenced by the dipole moment and the hydrogen bond, and the dielectric constant can be used as a parameter to judge the compatibility of the plasticizer. According to the research results of PVC, the solubility parameters of plasticizers generally range from 8.4 to 11.4 and the dielectric constant is 4~8, so the compatibility is ideal.
The plasticizing efficiency of the plasticizer is the amount of the resin to a certain degree of softness. Generally, the plasticization efficiency of low molecular weight and linear alkane chain structure is high, and its molecular weight is high, its molecular structure is compact and polar, and the plasticizing efficiency of branched chain and ring structure is much lower. For example, in the case of the same alkyl carbon number and the same structure, diacid ester > phthalate ester > dibenzoate ester.
The factors of durability of plasticizers include volatilization, extraction and migration in processing and application. Volatility refers to the diffusion of plasticizers from the surface of the products to the air when they are heated. As volatilization occurs, it may lead to the occurrence of atomization and aging.
The molecular weight of the plasticizer has a great influence on the volatility, and the increase of molecular weight helps to inhibit volatilization, and conversely, the volatility is larger. The loss of the extraction of plasticizers refers to the loss of plasticizers from the plasticizer to the liquid medium, which is closely related to the properties of the liquid medium.
The migration phenomenon occurred in the plastic products in contact with other solid polymer applications, because plasticizer molecules migrate from high concentration to plasticizing another polymer medium, often lead to product surface softening, sticky and even fragmentation, actual migration resistance is resistant to pollution. It has been proved that plasticizers with good compatibility with PVC, large molecular weight and with branched chain or benzene ring structure are difficult to migrate.
Copyright: Zhang Jia Gang YaRui Chemical co.,Ltd
http://www.yaruichem.com
The plasticizing mechanism of PVC (polyvinyl chloride) plasticizer is introduced in this paper. The selection method of PVC (polyvinyl chloride) plasticizer was analyzed.
Plasticizer is a material added to materials (usually plastics, resins or elastomers) to improve their workability, plasticity, flexibility and tensile properties, but they will not change the basic chemical properties of plasticized materials. It is mainly applied to polyvinyl chloride (PVC) resin. The amount of PVC can account for more than 98% of the total plasticizer consumption. Therefore, the development of plasticizer is closely related to the development of PVC industry.
The research and development of plasticizer for PVC (PVC) is focused on developing and producing more plasticizers with high performance, functionalization, innocuity and specialization, and further improving the production process.
The plasticizing mechanism of PVC (polyvinyl chloride) plasticizer. Plasticizer modified PVC has two main functions: one is to reduce the melting temperature and melt viscosity of PVC, thereby reducing its processing temperature; the other is to give PVC products softness, elasticity and low temperature resistance.
Plasticizers can be divided into two kinds of plasticizers and external plasticizers according to their principle and mode of action. The internal plasticizer changes the structure of PVC by chemical method so as to achieve the plasticizing effect. The advantage of internal plasticization is that the soft and hard segments have stable chemical bonding, and there is no disadvantage of loss of migration and volatilization. The disadvantage is that internal plasticization has some limitations on chemical modification of PVC resin, technically or economically.
External plasticizers are usually highly volatile high boiling esters. A few of them are low melting point solids. They generally do not react with PVC. Their plasticizing effect is achieved by coupling and shielding effects of plasticizers on PVC resin.
The coupling effect is the interaction between polar groups of plasticizer and polar group of PVC resin instead of polar connection between the original polymer molecules. Generally, the former force is weaker than the latter, which reduces the secondary valence of polymer. In addition, the polar parts of polar plasticizers still have the function of shielding the polar group of PVC, which can make the polar groups of neighboring polymer molecules not act, but also reduce the intermolecular force and increase plasticity.
The selection of plasticizers. When the plasticizer is used in the formula, its compatibility and plasticizing efficiency are the factors that should be taken into consideration in the PVC plasticizer.
The compatibility of plasticizers also adapts to the principle of "similarity and consistency". Plasticizers are physically bound by physical forces rather than chemical forces (chemical bonds). Therefore, the more the solubility parameter of the plasticizer is closer to the solubility parameter of the resin, the better the compatibility of the two.
Physical and chemical properties of two octyl terephthalate (plasticizer DOTP)
Appearance: transparent and colorless liquid
Boiling point: 400 degrees centigrade
Density: 0.984
Melting point: 30-34 degrees centigrade
Flash point: 238 degrees centigrade
Refractive index: 1.489-1.491
Flash point centigrade 210
Water is less than or equal to 0.03
Acid value is less than 0.1 mgKOH/g
The refractive index is greater than or equal to 1.4900 (20 C)
Color = (platinum cobalt) 30
The ester content% (chromatography) more than 99.5
Density (20 C) g/cm3 0.981-0.985
Use of two octyl terephthalate (plasticizer DOTP)
1.DOTP has good electrical and thermal properties. It can be used to replace DOP in the sheath of PVC plastic wire and can also be used in the production of artificial leather membrane. In addition, with excellent compatibility, terephthalic acid ester is two PVC acrylonitrile derivatives plastic plasticizer, plasticizer, plasticizer, polyvinyl butyral nitrile rubber plasticizer, plasticizer for cellulose nitrate. The improvement of the product and plays the role of hardness and deformation, can be used as softener in NBR, chloroprene rubber, EPDM rubber and other products three. Especially for cable material, it has good plasticizing effect and low volatility. It is widely used in various products that require heat resistance and high insulation. It is an ideal plasticizer for producing 70 PVC cable material and other volatile resistant products.
2.DOTP is used for the PVC products in the car, which can solve the fog problem of the glass window. DOTP is also used for high quality lubricants or lubricant additives furniture and interior decoration paint, and precision instruments, nitro varnish additives, paper softener, biaxially oriented polyester amide membrane film, plastic bags and other crafts, plasma storage.
3. because the linear molecular structure of DOTP is similar to DOS and DOA, its cold resistance is also better.
The volume resistivity of 4.DOTP is 10-20 times higher than that of DOP, and its mobility is excellent.
5., because DOTP does not contain o-phthalate two formate, it is not an environmental friendly plasticizer in the range of 16 16 kinds of plasticizers containing o-phthalic acid in the European Union and other countries.
Generally speaking, the polarity of plasticizer has the greatest influence on the compatibility. The compatibility between the middle molecules of the same kind is poorer, for example, the compatibility of C4 two C10 esters decreases. Polyol esters have better compatibility than monol esters. Polyester is poor in compatibility because of its large molecular weight.
The dielectric constant is a function of the molecular polarity, which is greatly influenced by the dipole moment and the hydrogen bond, and the dielectric constant can be used as a parameter to judge the compatibility of the plasticizer. According to the research results of PVC, the solubility parameters of plasticizers generally range from 8.4 to 11.4 and the dielectric constant is 4~8, so the compatibility is ideal.
The plasticizing efficiency of the plasticizer is the amount of the resin to a certain degree of softness. Generally, the plasticization efficiency of low molecular weight and linear alkane chain structure is high, and its molecular weight is high, its molecular structure is compact and polar, and the plasticizing efficiency of branched chain and ring structure is much lower. For example, in the case of the same alkyl carbon number and the same structure, diacid ester > phthalate ester > dibenzoate ester.
The factors of durability of plasticizers include volatilization, extraction and migration in processing and application. Volatility refers to the diffusion of plasticizers from the surface of the products to the air when they are heated. As volatilization occurs, it may lead to the occurrence of atomization and aging.
The molecular weight of the plasticizer has a great influence on the volatility, and the increase of molecular weight helps to inhibit volatilization, and conversely, the volatility is larger. The loss of the extraction of plasticizers refers to the loss of plasticizers from the plasticizer to the liquid medium, which is closely related to the properties of the liquid medium.
The migration phenomenon occurred in the plastic products in contact with other solid polymer applications, because plasticizer molecules migrate from high concentration to plasticizing another polymer medium, often lead to product surface softening, sticky and even fragmentation, actual migration resistance is resistant to pollution. It has been proved that plasticizers with good compatibility with PVC, large molecular weight and with branched chain or benzene ring structure are difficult to migrate.
Copyright: Zhang Jia Gang YaRui Chemical co.,Ltd
http://www.yaruichem.com
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