High temperature resistant polyvinyl chloride insulating material and its application in cable

Abstract

The application relates to the technical field of insulating materials, and discloses a high-temperature-resistant polyvinyl chloride insulating material and application thereof in cables, which is prepared from p-chloroaniline, formaldehyde, bisphenol S, diethanolamine, phthalic anhydride and the like as raw materials through Mannich reaction, substitution reaction and ring-opening polymerization reaction to obtain phthalic anhydride polyester polyol, and then the phthalic anhydride polyester polyol, 4,4-diphenyl methane diisocyanate and 1,4-butanediol are used as raw materials to obtain modified thermoplastic polyurethane; the modified thermoplastic polyurethane is initiated and crosslinked with polyvinyl chloride resin and the like, is uniformly mixed, and the high-temperature-resistant polyvinyl chloride insulating material is obtained; and the polyvinyl chloride insulating material prepared by the application has good high-temperature resistance and wear resistance.

Description

Technical Field

[0001] This invention relates to the field of insulation materials technology, specifically to a high-temperature resistant polyvinyl chloride insulation material and its application in cables. Background Technology

[0002] Polyvinyl chloride (PVC) possesses excellent properties such as flame retardancy and insulation, and is widely used in chemical, construction, and agricultural fields. PVC insulation materials have excellent physical and mechanical properties and chemical properties, but their high-temperature resistance and wear resistance are poor. Furthermore, with the rapid development of science and technology, traditional PVC insulation materials can no longer meet practical needs. Therefore, how to improve the wear resistance and high-temperature resistance of PVC insulation materials to meet the ever-increasing practical demands has become a current research hotspot.

[0003] Thermoplastic polyurethane is a high-performance elastomer with excellent acid and alkali resistance and mechanical properties, and is widely used in chemical, agricultural, and mechanical fields. For example, patent application CN116178933A discloses a high flame-retardant and high abrasion-resistant cable material and cable. This invention uses thermoplastic polyurethane elastomer, polyvinyl chloride, and other raw materials to prepare a cable material with good flame retardancy and mechanical properties, but it does not improve the material's high-temperature resistance. Summary of the Invention

[0004] (a) Technical problems to be solved

[0005] To address the shortcomings of existing technologies, this invention provides a high-temperature resistant polyvinyl chloride insulation material and its application in cables. The prepared insulation material exhibits good high-temperature resistance and wear resistance.

[0006] (II) Technical Solution

[0007] A high-temperature resistant polyvinyl chloride (PVC) insulating material, wherein the high-temperature resistant PVC insulating material is composed of the following components by weight:

[0008] 100 parts by weight of polyvinyl chloride resin, 30-50 parts by weight of plasticizer, 0.1-0.5 parts by weight of initiator, 0.5-1 parts by weight of antioxidant, 6-10 parts by weight of stabilizer, 2-5 parts by weight of co-crosslinking agent, and 10-30 parts by weight of modified thermoplastic polyurethane;

[0009] The high-temperature resistant polyvinyl chloride insulating material is prepared by the following method:

[0010] Polyvinyl chloride resin, plasticizer trioctyl trimellitate (TOTM), initiator dicumyl peroxide (DCP), antioxidant, stabilizer, and crosslinking agent triallyl isocyanurate (TAIC) are added to a high-speed mixer and stirred for 10-30 minutes. Then, modified thermoplastic polyurethane is added and the mixture is stirred for another 5-10 minutes. The mixture is then discharged to obtain high-temperature resistant polyvinyl chloride insulation material.

[0011] According to the above technical solution, in a preferred embodiment, the modified thermoplastic polyurethane is prepared by the following method:

[0012] Step (1) Add p-chloroaniline and 35-40% formaldehyde aqueous solution to a flask containing dioxane solvent, stir and mix at 5-10℃ for 12-20 min, then add bisphenol S, react at 90-100℃ for 5-10 h, after the reaction is completed, distill under reduced pressure, wash with deionized water, and dry to obtain intermediate 1.

[0013] Step (2) Add intermediate 1 to a flask containing ethanol solvent, stir and disperse, then add diethanolamine, and react at 95-110℃ for 10-18h. After the reaction is completed, remove the solvent by rotary evaporation under reduced pressure to obtain benzoxazinyl polyol.

[0014] Step (3) Under nitrogen conditions, benzoxazinyl polyol and phthalic anhydride are added to a flask, stirred and dispersed, and then 3% tetrabutyl titanate is added. The mixture is reacted at 140-160℃ for 20-36h. After the reaction is completed, the temperature is lowered to room temperature to obtain phthalic anhydride polyester polyol.

[0015] Step (4) Add the vacuum-dehydrated phthalic anhydride polyester polyol to a beaker, control the temperature at 50-60℃, stir for 20-30 min, then add 4,4-diphenylmethane diisocyanate, react at 60-70℃ for 30-50 min, then add 1,4-butanediol, stir at 70-80℃ for 1-2 min, place in a nitrogen-protected 120℃ oven, and cure for 3-5 h. After completion, cool to room temperature to obtain modified thermoplastic polyurethane.

[0016] According to the above technical solution, in a preferred case, in step (1), the mass ratio of p-chloroaniline to bisphenol S is 1-1.5:1.

[0017] According to the above technical solution, in a preferred case, in step (2), the mass ratio of intermediate 1 to diethanolamine is 1:0.35-0.5.

[0018] According to the above technical solution, in a preferred case, in step (3), the mass ratio of benzoxazinyl polyol to phthalic anhydride is 2-5:1.

[0019] According to the above technical solution, in a preferred case, in step (4), the mass ratio of phthalic anhydride polyester polyol, 4,4-diphenylmethane diisocyanate, and 1,4-butanediol is 1:0.55-0.9:0.2-0.35.

[0020] According to the above technical solution, in a preferred embodiment, the high-temperature resistant polyvinyl chloride insulation material is used in the preparation of cables.

[0021] (III) Beneficial Technical Effects

[0022] This invention uses p-chloroaniline, formaldehyde, and bisphenol S as raw materials. Through the Mannich reaction, intermediate 1 is obtained. Intermediate 1 is then reacted with diethanolamine via a substitution reaction to obtain benzoxazinyl polyol. Benzoxazinyl polyol and phthalic anhydride are then subjected to a ring-opening polymerization reaction under the catalysis of tetrabutyl titanate to obtain phthalic anhydride polyester polyol. Using phthalic anhydride polyester polyol, 4,4-diphenylmethane diisocyanate, and 1,4-butanediol as raw materials, modified thermoplastic polyurethane is obtained. This is then blended and crosslinked with polyvinyl chloride resin to obtain a high-temperature resistant polyvinyl chloride insulation material.

[0023] The intermediate 1 prepared by the Mannich reaction in this invention contains benzene ring structures and six-membered ring structures, which are heat-resistant rigid groups. Adding these to the insulating material increases the heat resistance of polyvinyl chloride (PVC). Furthermore, the six-membered ring structure absorbs heat and undergoes ring-opening crosslinking upon heating, further enhancing the heat resistance and wear resistance of the insulating material. In the presence of a co-crosslinking agent, the modified thermoplastic polyurethane prepared by this invention can initiate a crosslinking reaction between PVC and the modified thermoplastic polyurethane, increasing the degree of crosslinking and thus improving the wear resistance and high-temperature resistance of the insulating material. Moreover, the insulating material prepared by this invention has been experimentally verified to have good wear resistance and high-temperature resistance. Attached Figure Description

[0024] Figure 1 This is the preparation route for benzoxazinyl polyols. Detailed Implementation

[0025] The following embodiments are merely examples of implementation schemes of the present invention and do not constitute any limitation on the present invention. Those skilled in the art will understand that any modifications that do not depart from the spirit and concept of the present invention fall within the protection scope of the present invention.

[0026] Example 1

[0027] Step (1) Add 13g of p-chloroaniline and 40% formaldehyde aqueous solution to a flask containing dioxane solvent, stir and mix at 10°C for 15 min, then add 13g of bisphenol S, react at 100°C for 6 h, after the reaction is completed, distill under reduced pressure, wash with deionized water, and dry to obtain intermediate 1.

[0028] Step (2) Add 20g of intermediate 1 to a flask containing ethanol solvent, stir and disperse, then add 8g of diethanolamine, and react at 100℃ for 16h. After the reaction is completed, remove the solvent by rotary evaporation under reduced pressure to obtain benzoxazinyl polyol.

[0029] Step (3) Under nitrogen conditions, 30g of benzoxazinyl polyol and 10g of phthalic anhydride were added to a flask, stirred and dispersed, and then 3% tetrabutyl titanate was added. The mixture was reacted at 150°C for 28h. After the reaction was completed, the mixture was cooled to room temperature to obtain phthalic anhydride polyester polyol.

[0030] Step (4) Add 50g of phthalic anhydride polyester polyol that has been dehydrated under vacuum to a beaker, control the temperature at 55℃, stir for 30min, then add 45g of 4,4-diphenylmethane diisocyanate, react at 65℃ for 40min, then add 12g of 1,4-butanediol, stir at 80℃ for 2min, place in a nitrogen-protected 120℃ oven, and cure for 4h. After the curing is completed, cool to room temperature to obtain modified thermoplastic polyurethane.

[0031] Step (5) Add 100g of polyvinyl chloride resin, 50g of plasticizer TOTM, 0.4g of initiator DCP, 1g of antioxidant bisphenol A, 8g of calcium zinc stabilizer, and 5g of crosslinking agent TAIC to a high-speed mixer and stir for 20 minutes. Then add 10g of modified thermoplastic polyurethane and continue mixing for 10 minutes. Discharge the material to obtain high-temperature resistant polyvinyl chloride insulation material.

[0032] Example 2

[0033] Step (1) Add 15g of p-chloroaniline and 40% formaldehyde aqueous solution to a flask containing dioxane solvent, stir and mix at 5°C for 20min, then add 13g of bisphenol S, react at 90°C for 10h, after the reaction is completed, distill under reduced pressure, wash with deionized water, and dry to obtain intermediate 1.

[0034] Step (2) Add 20g of intermediate 1 to a flask containing ethanol solvent, stir and disperse, then add 8g of diethanolamine, and react at 100℃ for 12h. After the reaction is completed, remove the solvent by rotary evaporation under reduced pressure to obtain benzoxazinyl polyol.

[0035] Step (3) Under nitrogen conditions, 50g of benzoxazinyl polyol and 10g of phthalic anhydride were added to a flask, stirred and dispersed, and then 3% by mass of tetrabutyl titanate was added. The mixture was reacted at 150℃ for 24h. After the reaction was completed, the mixture was cooled to room temperature to obtain phthalic anhydride polyester polyol.

[0036] Step (4) Add 50g of phthalic anhydride polyester polyol that has been dehydrated under vacuum to a beaker, control the temperature at 50℃, stir for 25min, then add 27.5g of 4,4-diphenylmethane diisocyanate, react at 60℃ for 50min, then add 10g of 1,4-butanediol, stir at 75℃ for 1min, place in a nitrogen-protected 120℃ oven, and cure for 5h. After the curing is completed, cool to room temperature to obtain modified thermoplastic polyurethane.

[0037] Step (5) Add 100g of polyvinyl chloride resin, 40g of plasticizer TOTM, 0.4g of initiator DCP, 0.6g of antioxidant bisphenol A, 9g of calcium zinc stabilizer, and 5g of crosslinking agent TAIC to a high-speed mixer and stir for 20 minutes. Then add 15g of modified thermoplastic polyurethane and continue mixing for 6 minutes. Discharge the material to obtain high-temperature resistant polyvinyl chloride insulation material.

[0038] Example 3

[0039] Step (1) Add 19.5g of p-chloroaniline and 35% formaldehyde aqueous solution to a flask containing dioxane solvent, stir and mix at 10°C for 12 min, then add 13g of bisphenol S, react at 95°C for 5 h, after the reaction is completed, distill under reduced pressure, wash with deionized water, and dry to obtain intermediate 1.

[0040] Step (2) Add 20g of intermediate 1 to a flask containing ethanol solvent, stir and disperse, then add 8g of diethanolamine, and react at 110℃ for 12h. After the reaction is completed, remove the solvent by rotary evaporation under reduced pressure to obtain benzoxazinyl polyol.

[0041] Step (3) Under nitrogen conditions, 20g of benzoxazinyl polyol and 10g of phthalic anhydride were added to a flask, stirred and dispersed, and then 3% tetrabutyl titanate was added. The mixture was reacted at 140℃ for 20h. After the reaction was completed, the mixture was cooled to room temperature to obtain phthalic anhydride polyester polyol.

[0042] Step (4) Add 50g of phthalic anhydride polyester polyol that has been vacuum dehydrated to a beaker, control the temperature at 60℃, stir for 20min, then add 35g of 4,4-diphenylmethane diisocyanate, react at 70℃ for 30min, then add 17.5g of 1,4-butanediol, stir at 70℃ for 2min, place in a nitrogen-protected 120℃ oven, and cure for 3h. After completion, cool to room temperature to obtain modified thermoplastic polyurethane.

[0043] Step (5) Add 100g of polyvinyl chloride resin, 30g of plasticizer TOTM, 0.5g of initiator DCP, 0.5g of antioxidant bisphenol A, 10g of calcium zinc stabilizer, and 4g of crosslinking agent TAIC to a high-speed mixer and stir for 20 minutes. Then add 20g of modified thermoplastic polyurethane and continue mixing for 5 minutes. Discharge the material to obtain high-temperature resistant polyvinyl chloride insulation material.

[0044] Example 4

[0045] Step (1) Add 18g of p-chloroaniline and 40% formaldehyde aqueous solution to a flask containing dioxane solvent, stir and mix at 5°C for 20 min, then add 13g of bisphenol S, react at 95°C for 6 h, after the reaction is completed, distill under reduced pressure, wash with deionized water, and dry to obtain intermediate 1.

[0046] Step (2) Add 20g of intermediate 1 to a flask containing ethanol solvent, stir and disperse, then add 10g of diethanolamine, and react at 95℃ for 18h. After the reaction is completed, remove the solvent by rotary evaporation under reduced pressure to obtain benzoxazinyl polyol.

[0047] Step (3) Under nitrogen conditions, 30g of benzoxazinyl polyol and 10g of phthalic anhydride were added to a flask, stirred and dispersed, and then 3% tetrabutyl titanate was added. The mixture was reacted at 150°C for 36h. After the reaction was completed, the mixture was cooled to room temperature to obtain phthalic anhydride polyester polyol.

[0048] Step (4) Add 50g of phthalic anhydride polyester polyol that has been vacuum dehydrated to a beaker, control the temperature at 55℃, stir for 30min, then add 40g of 4,4-diphenylmethane diisocyanate, react at 65℃ for 40min, then add 16g of 1,4-butanediol, stir at 80℃ for 1min, place in a nitrogen-protected 120℃ oven, and cure for 4h. After completion, cool to room temperature to obtain modified thermoplastic polyurethane.

[0049] Step (5) Add 100g of polyvinyl chloride resin, 40g of plasticizer TOTM, 0.3g of initiator DCP, 1g of antioxidant bisphenol A, 6g of calcium zinc stabilizer, and 5g of crosslinking agent TAIC to a high-speed mixer and stir for 30 minutes. Then add 25g of modified thermoplastic polyurethane and continue mixing for 5 minutes. Discharge the material to obtain high-temperature resistant polyvinyl chloride insulation material.

[0050] Example 5

[0051] Step (1) Add 16g of p-chloroaniline and 38% formaldehyde aqueous solution to a flask containing dioxane solvent, stir and mix at 10°C for 15 min, then add 13g of bisphenol S, react at 95°C for 6 h, after the reaction is completed, distill under reduced pressure, wash with deionized water, and dry to obtain intermediate 1.

[0052] Step (2) Add 20g of intermediate 1 to a flask containing ethanol solvent, stir and disperse, then add 7g of diethanolamine, and react at 100℃ for 10h. After the reaction is completed, remove the solvent by rotary evaporation under reduced pressure to obtain benzoxazinyl polyol.

[0053] Step (3) Under nitrogen conditions, 50g of benzoxazinyl polyol and 10g of phthalic anhydride were added to a flask, stirred and dispersed, and then 3% by mass of tetrabutyl titanate was added. The mixture was reacted at 140℃ for 24h. After the reaction was completed, the mixture was cooled to room temperature to obtain phthalic anhydride polyester polyol.

[0054] Step (4) Add 50g of phthalic anhydride polyester polyol that has been vacuum dehydrated to a beaker, control the temperature at 55℃, stir for 25min, then add 40g of 4,4-diphenylmethane diisocyanate, react at 65℃ for 40min, then add 15g of 1,4-butanediol, stir at 75℃ for 2min, place in a nitrogen-protected 120℃ oven, and cure for 4h. After completion, cool to room temperature to obtain modified thermoplastic polyurethane.

[0055] Step (5) Add 100g of polyvinyl chloride resin, 50g of plasticizer TOTM, 0.1g of initiator DCP, 0.8g of antioxidant bisphenol A, 6g of calcium zinc stabilizer, and 2g of crosslinking agent TAIC to a high-speed mixer and stir for 10 minutes. Then add 30g of modified thermoplastic polyurethane and continue mixing for 10 minutes. Discharge the material to obtain high-temperature resistant polyvinyl chloride insulation material.

[0056] Comparative Example 1

[0057] The difference between this comparative example and Example 1 is that in step (4), polyhexamethylene adipate is used instead of phthalic anhydride polyester polyol.

[0058] Comparative Example 2

[0059] The difference between this comparative example and Example 1 is that step (5) does not contain modified thermoplastic polyurethane.

[0060] High temperature resistance test: The insulating material was placed in a 150℃ high temperature oven for 10 days, then removed and its tensile properties were tested according to GB / T1040.1-2018. The change rate of tensile strength (%) = tensile strength after aging (MPa) / tensile strength before aging (MPa).

[0061] Table 1. Changes in tensile strength of Examples 1-5 and Comparative Examples 1-2

[0062] Tensile strength change rate (%) Example 1 +17.2 Example 2 +19.1 Example 3 +20.5 Example 4 +22.4 Example 5 +22.0 Comparative Example 1 +15.4 Comparative Example 2 -12.45

[0063] As shown in Table 1, the tensile strength change rate of Examples 1-5 and Comparative Example 1 is larger than that of Comparative Example 2. This is because Examples 1-5 and Comparative Example 1 generate more crosslinking density during the thermal aging process, which increases the mechanical properties of the material. However, Comparative Example 2 does not contain polyurethane, so its mechanical properties decrease with thermal aging. The tensile strength change rate of Examples 1-5 is larger than that of Comparative Example 1 because Examples 1-5 contain more rigid structures, which are better heat-resistant structures. Furthermore, the benzoxazine structure can undergo ring-opening crosslinking when heated, further improving the mechanical properties and high-temperature resistance of the insulation material. Therefore, the tensile strength change rate of Examples 1-5 is larger than that of Comparative Example 1. Thus, the insulation material prepared by this invention has better high-temperature resistance.

[0064] Press the material into a 3mm thin sheet, weigh it to an accuracy of 0.001g, place the sheet on an abrasion tester, and perform abrasion under the same conditions and for the same number of times. After the abrasion is completed, remove the sheet and weigh it. Calculate the difference in mass of the sheet before and after abrasion, which is the amount of wear. The smaller the amount of wear, the better the abrasion resistance of the material.

[0065] Table 2 Wear Amounts of Examples 1-5 and Comparative Examples 1-2

[0066] Wear amount (g) Example 1 1.0019 Example 2 0.9891 Example 3 0.9804 Example 4 0.9724 Example 5 0.9753 Comparative Example 1 1.0595 Comparative Example 2 1.4824

[0067] As shown in Table 2, the insulating material prepared by this invention has good wear resistance.

[0068] For anyone skilled in the art, many possible variations and modifications can be made to the technical solutions of this invention, or equivalent embodiments can be modified based on the disclosed technical content, without departing from the scope of the technical solutions of this invention. Therefore, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of this invention without departing from the content of the technical solutions of this invention should still fall within the protection scope of the technical solutions of this invention.

Claims

1. A high-temperature resistant polyvinyl chloride insulation material, characterized in that, The high-temperature resistant polyvinyl chloride insulation material is composed of the following components by weight: 100 parts by weight of polyvinyl chloride resin, 30-50 parts by weight of plasticizer, 0.1-0.5 parts by weight of initiator, 0.5-1 parts by weight of antioxidant, 6-10 parts by weight of stabilizer, 2-5 parts by weight of co-crosslinking agent, and 10-30 parts by weight of modified thermoplastic polyurethane; The high-temperature resistant polyvinyl chloride insulating material is prepared by the following method: Polyvinyl chloride resin, plasticizer, initiator, antioxidant, stabilizer, and crosslinking agent are added to a high-speed mixer and stirred for 10-30 minutes. Then, modified thermoplastic polyurethane is added and the mixture is stirred for another 5-10 minutes. The mixture is then discharged to obtain high-temperature resistant polyvinyl chloride insulation material. The modified thermoplastic polyurethane is prepared by the following method: Step (1) Add p-chloroaniline and 35-40% formaldehyde aqueous solution to a flask containing dioxane solvent, stir and mix at 5-10℃ for 12-20 min, then add bisphenol S, react at 90-100℃ for 5-10 h, after the reaction is completed, distill under reduced pressure, wash with deionized water, and dry to obtain intermediate 1. Step (2) Add intermediate 1 to a flask containing ethanol solvent, stir and disperse, then add diethanolamine, and react at 95-110℃ for 10-18h. After the reaction is completed, remove the solvent by rotary evaporation under reduced pressure to obtain benzoxazinyl polyol. Step (3) Under nitrogen conditions, benzoxazinyl polyol and phthalic anhydride are added to a flask, stirred and dispersed, and then 3% tetrabutyl titanate is added. The mixture is reacted at 140-160℃ for 20-36h. After the reaction is completed, the temperature is lowered to room temperature to obtain phthalic anhydride polyester polyol. Step (4) Add the vacuum-dehydrated phthalic anhydride polyester polyol to a beaker, control the temperature at 50-60℃, stir for 20-30 min, then add 4,4-diphenylmethane diisocyanate, react at 60-70℃ for 30-50 min, then add 1,4-butanediol, stir at 70-80℃ for 1-2 min, place in a nitrogen-protected 120℃ oven, and cure for 3-5 h. After completion, cool to room temperature to obtain modified thermoplastic polyurethane.

2. The high-temperature resistant polyvinyl chloride insulation material as described in claim 1, characterized in that, In step (1), the mass ratio of p-chloroaniline to bisphenol S is 1-1.5:

1.

3. The high-temperature resistant polyvinyl chloride insulation material as described in claim 1, characterized in that, In step (2), the mass ratio of intermediate 1 to diethanolamine is 1:0.35-0.

5.

4. The high-temperature resistant polyvinyl chloride insulation material as described in claim 1, characterized in that, In step (3), the mass ratio of benzoxazinyl polyol to phthalic anhydride is 2-5:

1.

5. The high-temperature resistant polyvinyl chloride insulation material as described in claim 1, characterized in that, In step (4), the mass ratio of phthalic anhydride polyester polyol, 4,4-diphenylmethane diisocyanate, and 1,4-butanediol is 1:0.55-0.9:0.2-0.

35.

6. The application of the high-temperature resistant polyvinyl chloride insulation material as described in claim 1 in the preparation of cables.

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