Plasticizer for cable and application thereof

Abstract

The invention belongs to the field of cables, and particularly relates to a plasticizer for cables and application thereof.Compared with the prior art, a PVC cable material prepared through the method has the very good mechanical property, the volatility and mobility loss of the plasticizer is extremely low, especially, the plasticizer shows very good migration resistance in petroleum ether, and in addition, the plasticizer has the advantages of being environmentally friendly and free of pollution. The invention further provides a novel plasticizer which is small in dosage, simple in preparation method and suitable for industrial production. # imgabs0 # (I)

Description

Technical Field

[0001] The present invention belongs to the field of cables, and particularly relates to a plasticizer for cables and its application. Background Art

[0002] PVC is a commonly used engineering plastic, widely used in fields such as food packaging, toys, wire and cable, etc., and is a very common material in daily life. However, due to problems such as brittleness and toughness of pure PVC materials, they cannot be directly used in industrial processing, and a certain amount of plasticizer often needs to be added to PVC. Plasticizers are the most used auxiliaries in PVC, which can improve the flexibility and toughness of PVC and are easy to process. Currently, the most commonly used plasticizers in PVC cables include: dioctyl phthalate (DOP), diisodecyl phthalate (DIDP), dioctyl terephthalate (DOTP), trioctyl trimellitate (TOTM), and epoxidized soybean oil (ESO), etc. Among them, the most commonly used plasticizers are phthalate esters, and their annual consumption accounts for more than 70% of the total amount of plasticizers. However, such plasticizers are prone to migration in PVC cables, such as being extracted by solvents and volatilizing when heated, and will pollute the environment and damage human health during this process, and have reproductive toxicity and carcinogenicity. Therefore, they are gradually prohibited from being used in many fields. Therefore, it is imperative to develop new, efficient, and sustainable bio-based plasticizers using environmentally friendly and renewable raw materials.

[0003] Currently, there have been reports on environmentally friendly plasticizers. For example, Patent CN101607905B discloses a preparation method of a naphthenic anhydride plasticizer. This type of plasticizer does not contain a benzene ring, is environmentally friendly, non-toxic to humans, and has the advantage of high impedance, but the amount of plasticizer used is large; Patent CN107573244B discloses an acylated p-hydroxycinnamate plasticizer and its preparation method. Using the bio-based platform compound p-hydroxycinnamic acid derived from renewable resources as a raw material, a non-toxic and highly efficient acylated p-hydroxycinnamate environmentally friendly plasticizer is synthesized. However, this type of plasticizer has problems such as a large amount of usage, large migration and volatile losses; Patent CN 115304504B discloses an environmentally friendly cable and its manufacturing process, providing a new type of environmentally friendly PVC plasticizer, avoiding the use of phthalate plasticizers, and its performance has no significant difference from that of a PVC cable using phthalate as a plasticizer, but the amount of plasticizer used is large.

[0004] In summary, the existing cables in the prior art have problems such as being non-environmentally friendly, large amount of plasticizer used, and large migration and volatile losses. Therefore, there is an urgent need to provide more environmentally friendly plasticizers with a low amount of plasticizer used and small migration and volatile losses. Summary of the Invention

[0005] The object of the present invention is to provide a plasticizer for cables which is environmentally friendly, has a low plasticizer dosage, and has small migration and volatility losses, so as to solve the problems of environmental unfriendliness, large plasticizer dosage, and large migration and volatility losses existing in cables in the prior art.

[0006] The present invention is achieved through the following technical solutions. The present invention provides a plasticizer for cables, characterized in that the plasticizer for cables has a structure as shown in general formula I: (I).

[0007] Furthermore, the present invention also provides a preparation method of a plasticizer for cables, characterized by including the following steps: 1) Take a certain amount of 3-(6-hydroxy-2-naphthyl)-2-acrylic acid and n-butanol and place them in a three-necked flask equipped with a condenser reflux device and a water separator. Then add a certain amount of toluene and stannous oxide, seal the three-necked flask, turn on the stirring and reflux water, heat to reflux and continue reflux reaction for a certain period of time. After the reaction is completed, perform post-treatment to obtain butyl 3-(6-hydroxy-2-naphthyl)-2-acrylate; 2) Take the butyl 3-(6-hydroxy-2-naphthyl)-2-acrylate, triethylamine and dichloromethane prepared in step 1) and place them in a three-necked flask equipped with a condenser reflux device. Under nitrogen protection and in an ice bath condition, slowly dropwise add isooctanoyl chloride. After the dropping is completed, continue to react in the ice bath condition for 4 hours. Subsequently, raise the reaction temperature to 50 °C and continue to react for 1 hour. After the reaction is completed, perform post-treatment to obtain the compound of formula (I); The specific synthesis route is as follows: .

[0008] Furthermore, as a preferred technical solution of the present invention, the molar ratio of 3-(6-hydroxy-2-naphthyl)-2-acrylic acid to n-butanol in step 1) is 1:10 - 30; preferably, the molar ratio of 3-(6-hydroxy-2-naphthyl)-2-acrylic acid to n-butanol in step 1) is 1:10 - 15; Furthermore, as a preferred technical solution of the present invention, the reflux reaction time in step 1) is 3 - 8 hours; preferably, the reflux reaction time in step 1) is 6 hours; Furthermore, as a preferred technical solution of the present invention, the molar ratio of 3-(6-hydroxy-2-naphthyl)-2-acrylic acid to stannous oxide in step 1) is: 1:0.03 - 0.5; preferably, the molar ratio of 3-(6-hydroxy-2-naphthyl)-2-acrylic acid to stannous oxide in step 1) is: 1:0.03 - 0.05; Further, as a preferred technical solution of the present invention, the volume ratio of toluene to n-butanol in step 1) is: 0.5 - 1:1; preferably, the volume ratio of toluene to n-butanol in step 1) is 0.5 - 0.6:1; Further, as a preferred technical solution of the present invention, the post-treatment steps in step 1) are: rotary evaporation to remove toluene and excess n-butanol, the residue is dissolved in dichloromethane, filtered, the filtrate is washed 3 times with saturated brine, dried over anhydrous sodium sulfate, filtered, and the solvent is removed by rotary evaporation.

[0009] Further, as a preferred technical solution of the present invention, the molar ratio of butyl 3-(6-hydroxy-2-naphthyl)-2-acrylate to isooctanoyl chloride in step 2) is 1:1.1 - 2; preferably, the molar ratio of butyl 3-(6-hydroxy-2-naphthyl)-2-acrylate to isooctanoyl chloride in step 2) is 1:1.1 - 1.5; Further, as a preferred technical solution of the present invention, the molar ratio of butyl 3-(6-hydroxy-2-naphthyl)-2-acrylate to triethylamine in step 2) is 1:1.2 - 3; preferably, the molar ratio of butyl 3-(6-hydroxy-2-naphthyl)-2-acrylate to triethylamine in step 2) is 1:1.5 - 2; Further, as a preferred technical solution of the present invention, the post-treatment steps in step 2) are: filtration, the filtrate is washed 3 times with saturated brine, dried over anhydrous sodium sulfate, filtered, and the solvent is removed by rotary evaporation.

[0010] Further, the present invention also provides a PVC cable material, which is characterized in that, by weight, it comprises the following raw materials: 100 - 120 parts of PVC resin, 20 - 40 parts of plasticizer, 10 - 20 parts of flame retardant, 3 - 6 parts of stabilizer, 30 - 40 parts of inorganic filler, 5 - 10 parts of lubricant; the plasticizer is selected from: (I); Further, as a preferred technical solution of the present invention, the PVC cable material is characterized in that, by weight, it comprises the following raw materials: 100 parts of PVC resin, 40 parts of plasticizer, 10 parts of flame retardant, 5 parts of stabilizer, 40 parts of inorganic filler, 10 parts of lubricant; the plasticizer is selected from: (I); Further, as a preferred technical solution of the present invention, the plasticizer is selected from: (I); Further, as a preferred technical solution of the present invention, the flame retardant is selected from one or more of antimony trioxide, calcium carbonate, magnesium carbonate, zinc borate and molybdenum trioxide; Further, as a preferred technical solution of the present invention, the stabilizer is selected from: calcium zinc stabilizer; Further, as a preferred technical solution of the present invention, the inorganic filler is selected from one or more of calcium carbonate, calcined clay, and silica white; Further, as a preferred technical solution of the present invention, the lubricant is selected from one or more of stearic acid, calcium stearate, barium stearate, and paraffin wax; Further, the present invention also provides a method for preparing a PVC cable compound, comprising the following steps: putting the formulated amount of PVC resin, plasticizer, flame retardant, stabilizer, and lubricant into a high-speed kneader, mixing and stirring evenly under the condition of 100 - 110 °C, then adding the inorganic filler, and mixing and stirring evenly under the condition of 80 °C to obtain a mixture; feeding the mixture into a twin-screw extruder and extruding and pelletizing under the condition of 150 - 160 °C to obtain the PVC cable compound.

[0011] Beneficial effects: 1) Compared with the prior art, the PVC cable compound prepared by the present invention not only has very good mechanical properties, but also has extremely low loss of volatility and migration of the plasticizer, especially showing very good migration resistance in petroleum ether; 2) The present invention provides a novel plasticizer, which not only has a small dosage, but also has a simple preparation method and is suitable for industrial production. Description of the drawings

[0012] 1) Figure 1 It is the NMR spectrum of the plasticizer for Example 1; 2) Figure 2 It is the test result of the volatility of the PVC cable compound prepared in Application Example 1 of the present invention; 3) Figure 3 It is the test result of the migration resistance of the PVC cable compound prepared in Application Example 1 of the present invention. Detailed implementation manners

[0013] The present invention will be further described in detail below with reference to the embodiments, but the content of the invention is not limited to the embodiments.

[0014] Example 1 Preparation of the plasticizer of the compound of formula (I) (I) The specific synthesis route is as follows:

[0015] Step A: Synthesis of 3-(6-hydroxy-2-naphthyl)-2-butenoic acid butyl ester 1) 21.4 g of 3-(6-hydroxy-2-naphthyl)-2-acrylic acid (0.1 mol) and 89 g (1.2 mol) of n-butanol were placed in a three-necked flask equipped with a condenser reflux device and a water separator. Then, 60 mL of toluene and 0.45 g of tin oxide (0.003 mol) were added. The three-necked flask was sealed, stirring and reflux water were started, and after heating to reflux, the reflux reaction was continued for 6 hours. After the reaction was completed, toluene and excess n-butanol were removed by rotary evaporation. The residue was dissolved in 100 mL of dichloromethane, filtered, and the filtrate was washed 3 times with saturated brine, dried over anhydrous sodium sulfate, filtered, and dichloromethane was removed by rotary evaporation to obtain 21.9 g of butyl 3-(6-hydroxy-2-naphthyl)-2-acrylate; [M+H] + = 271.06; Step B: Synthesis of the compound of formula (I) 2) 13.5 g of butyl 3-(6-hydroxy-2-naphthyl)-2-acrylate (0.05 mol) prepared in step 1), 7.6 g of triethylamine and 100 mL of dichloromethane were placed in a three-necked flask equipped with a condenser reflux device. Under nitrogen protection and in an ice bath, 9.8 g of isooctanoyl chloride (0.06 mol) was slowly added dropwise. After the addition was completed, the reaction was continued in an ice bath for 4 hours. Subsequently, the reaction temperature was raised to 50 °C and the reaction was continued for 1 hour. After the reaction was completed, the mixture was filtered, and the filtrate was washed 3 times with saturated brine, dried over anhydrous sodium sulfate, filtered, and dichloromethane was removed by rotary evaporation to obtain 16.8 g of the compound of formula (I). [M+H] + = 397.15. The NMR results are shown in Figure 1 .

[0016] Example 2 Synthesis of butyl octanoyl p-hydroxycinnamate

[0017] Butyl octanoyl p-hydroxycinnamate was prepared by referring to the method of Example 4 of Patent CN107573244B. [M+H] + = 349.12. Application Example 1 The plasticizers prepared in Examples 1-2 and the commercially available dioctyl terephthalate (DOTP) plasticizer were used as references for preparing PVC cable compounds. The specific formulation is shown in Table 1.

[0018] Table 1 PVC Cable Compound Formulation Table

[0019] Specific preparation method of PVC cable material, including the following steps: Put the formulated amount of PVC resin, plasticizer (plasticizer in Example 1, plasticizer in Example 2 or DOTP plasticizer), calcium-zinc stabilizer, antimony trioxide and stearic acid into a high-speed kneader, mix and stir evenly under the condition of 100 - 110 °C, then add calcined clay, and mix and stir evenly under the condition of 80 °C to obtain a mixture; Send the mixture into a twin-screw extruder and extrude and pelletize under the condition of 150 - 160 °C to obtain the PVC cable material. Performance test 1) Mechanical property test Refer to the test method in GB / T8815-2008 (Flexible Polyvinyl Chloride Plastics for Wire and Cable) to test the tensile strength and elongation at break of each PVC cable material in Application Example 1. The test results are shown in Table 2.

[0020] Table 2 Mechanical property data of each PVC cable material sample in Application Example 1

[0021] According to the results in Table 2, it can be seen that the PVC cable material prepared by the present invention has good mechanical properties, is slightly better than the PVC cable material obtained with DOTP as the plasticizer under the same conditions, and can still maintain good mechanical properties when the dosage of the plasticizer is reduced in the present invention.

[0022] 2) Volatility test This experiment was carried out according to the heating loss rate method in the standard GB / T3830-2008 (Flexible Polyvinyl Chloride Calendered Films and Sheets). Take each PVC cable material sample prepared in Application Example 1 and make test pieces with a length of 60 mm, a width of 40 mm and a thickness of 1 mm, with no less than 3 pieces for each sample. Place each test piece in a desiccator for 4 hours and then take it out. Weigh each piece one by one and record. Put it in a non-blowing oven at 100 °C ± 2 °C, take it out after constant temperature for 6 h, immediately put it into a desiccator and cool it to room temperature, then weigh it, and calculate the mass loss rate according to the following formula (1), and the result is the average value. The results are shown in Figure 2 .

[0023] Mass loss rate % = (m 1 - m 2 ) / m 1 × 100% (1) In the formula: m 1 : Mass of the sample before heating (unit: g) m 2 : Mass of the sample after heating (unit: g) According to Figure 2As can be seen from the results, the PVC cable compound prepared by the present invention has very low volatile loss, which is significantly better than the PVC cable compound obtained with DOTP as the plasticizer under the same conditions.

[0024] 3) Migration resistance test Solvent extraction resistance: Cut the sample into specimens about 1 cm × 1 cm in size and about 2 mm thick, with 3 specimens in each group. Wipe the surface of the specimens clean, place them in a dryer and dry for 4 hours, and accurately weigh the mass of the specimens on an analytical balance. Immerse the specimens in a certain amount of deionized water and petroleum ether separately at room temperature and let them stand still. After 48 hours, take them out, dry them, and then continue to dry them in an oven for 48 hours. Subsequently, weigh their mass, and calculate the mass loss rate of the specimens using formula (2). The results are shown in Figure 3 .

[0025] Mass loss rate % = (m 1 - m 2 ) / m 1 × 100% (2) In the formula: m 1 : Mass of the specimen before immersion (unit: g) m 2 : Mass of the specimen after immersion (unit: g) According to Figure 3 the results, it can be seen that the PVC cable compound prepared by the present invention has good migration resistance, especially with extremely low migration in petroleum ether, which is significantly better than the PVC cable compound obtained with DOTP as the plasticizer under the same conditions.

[0026] It should be understood that the above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. For those of ordinary skill in the art, improvements or transformations can be made according to the above description, and all such improvements and transformations should fall within the protection scope of the appended claims of the present invention.

Claims

1. A plasticizer for cables, characterized in that: The cable plasticizer has a structure as shown in general formula I: (I)。 2. A method for preparing the cable plasticizer according to claim 1, characterized in that ,, including the following steps: 1) taking a certain amount of 3-(6-hydroxy-2-naphthyl)-2-acrylic acid and n-butanol and placing them in a three-necked flask with a condensing reflux device and a water separator, adding a certain amount of toluene and tin oxide, sealing the three-necked flask, starting stirring and refluxing water, heating to reflux and then continuing reflux reaction for a certain time, after the reaction is completed, post-treating to obtain 3-(6-hydroxy-2-naphthyl)-2-acrylic acid butyl ester; 2) 3-(6-hydroxy-2-naphthyl)-2-butyl acrylate, triethylamine and dichloromethane prepared in step 1) were placed in a three-necked flask with a condensing reflux device, and isooctanoyl chloride was slowly added dropwise under nitrogen protection in an ice bath. After the addition was completed, the reaction was continued in an ice bath for 4 hours, and then the reaction temperature was raised to 50° C. and the reaction was continued for 1 hour. After the reaction was completed, post-treatment was performed to obtain a compound of formula (I); The specific synthetic route is as follows: 。 3. The preparation method according to claim 2, characterized in that: Further, as a preferred technical solution of the present invention, in the step 1), the molar ratio of 3-(6-hydroxy-2-naphthyl)-2-acrylic acid to n-butanol is 1:10-30; The reflux reaction time in step 1) is 3-8 hours; The molar ratio of 3-(6-hydroxy-2-naphthyl)-2-propenoic acid to tin oxide is: 1:0.03-0.5; In the step 1), the volume ratio of toluene to n-butanol is 0.5-1:1; The post-treatment step in step 1) is: toluene and excess n-butanol are removed by rotary evaporation, the residue is dissolved with dichloromethane, filtered, the filtrate is washed three times with saturated brine, dried with anhydrous sodium sulfate, filtered, and the solvent is removed by rotary evaporation.

4. The preparation method according to claim 2, characterized in that: In the step 2), the molar ratio of 3-(6-hydroxy-2-naphthyl)-2-butyl acrylate to isooctanoyl chloride is 1:1.1-2; In the step 2), the molar ratio of 3-(6-hydroxy-2-naphthyl)-2-butyl acrylate to triethylamine is 1:1.2-3; The post-treatment steps in step 2) are: filtering, washing the filtrate with saturated brine three times, drying with anhydrous sodium sulfate, filtering, and removing the solvent by rotary evaporation.

5. A PVC cable material, characterized in that: The following raw materials are included in parts by weight: 100-120 parts of PVC resin, 20-40 parts of plasticizer, 10-20 parts of flame retardant, 3-6 parts of stabilizer, 30-40 parts of inorganic filler, and 5-10 parts of lubricant; the plasticizer is selected from: (I).

6. The PVC cable material according to claim 5, characterized in that: The following raw materials are included in parts by weight: 100 parts of PVC resin, 40 parts of plasticizer, 10 parts of flame retardant, 5 parts of stabilizer, 40 parts of inorganic filler, and 10 parts of lubricant; the plasticizer is selected from: (I).

7. The PVC cable material according to claim 5 or 6, characterized in that: The plasticizer is selected from: (I); The flame retardant is selected from: one or more of antimony trioxide, calcium carbonate, magnesium carbonate, zinc borate and molybdenum trioxide; The stabilizer is selected from: calcium zinc stabilizer; The inorganic filler is selected from one or more of calcium carbonate, calcined clay and white carbon black; The lubricant is selected from one or more of stearic acid, calcium stearate, barium stearate and paraffin.

8. A method for preparing a PVC cable material according to any one of claims 5 to 7, characterized in that: The method comprises the following steps: putting a formulated amount of PVC resin, a plasticizer, a flame retardant, a stabilizer and a lubricant into a high-speed kneader, mixing and stirring them uniformly at 100-110° C., then adding an inorganic filler, mixing and stirring them uniformly at 80° C. to obtain a mixture; sending the mixture into a twin-screw extruder, extruding and granulating the mixture at 150-160° C. to obtain the PVC cable material.

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