High-temperature-resistant PET functional master batch and preparation method thereof

Abstract

The invention discloses a high-temperature-resistant PET (Polyethylene Terephthalate) functional master batch, which is prepared from the following raw materials in parts by weight: 50 to 100 parts by weight of terephthalic acid, 20 to 45 parts by weight of ethylene glycol, 5 to 10 parts by weight of dimethyl 2, 6-naphthalate, 0.02 to 0.04 part by weight of acetic anhydride, 0.03 to 0.05 part by weight of acetone, 0.005 to 0.01 part by weight of antimony dioxide and 0.01 to 0.03 part by weight of triethyl phosphate. The cleaning agent is prepared from the following components in parts by weight: 0.01 to 0.03 part of sodium dodecyl benzene sulfonate, 0.05 to 0.10 part of 2-hydroxy-4-(3-triethoxysilane propoxy) benzophenone, 0.10 to 0.15 part of ethanol and 0.01 to 0.03 part of cellulose acetate. The invention also discloses a preparation method corresponding to the high-temperature-resistant PET functional master batch. According to the invention, an optimized esterification dispersion catalysis system is adopted, and a latticed polysiloxane chain is added at the initial stage of polycondensation with a relatively small molecular chain, so that the latticed polysiloxane chain can be relatively easily dispersed into a master batch, the crystallinity of polyester is not influenced, and excellent high-temperature resistance can be obtained.

Description

Technical Field

[0001] The present invention relates to a high-temperature resistant PET functional masterbatch and a preparation method thereof. The functional additive can be prepared into particles or slices for use in industries such as high-temperature resistance, high mechanical strength, and chemical corrosion resistance. Background Art

[0002] High-temperature resistant PET (polyethylene terephthalate) maintains its properties at elevated temperatures and is widely used in a variety of fields. For example, in the electrical and electronics sector, high-temperature PET is commonly used to manufacture electrical insulation materials, electronic components, and connector housings. It maintains excellent insulation properties in high-temperature environments and offers strong impact resistance and dimensional stability. In the automotive industry, high-temperature resistant PET is commonly used in automotive parts such as engine components, cable sheathing, headlight reflectors, and sensor housings. These components often operate in high-temperature environments, and high-temperature resistant PET can effectively extend their service life and durability. In the packaging industry, high-temperature resistant PET can be used to manufacture packaging materials for foods that require high-temperature cooking. Its excellent heat resistance and barrier properties ensure food safety and quality even in high-temperature environments. In the machinery industry, due to its excellent mechanical strength and wear resistance, high-temperature resistant PET is used to manufacture mechanical components such as bearings, gears, and sliding guides. These components must withstand heavy mechanical loads and high temperatures during operation. In the medical device industry, high-temperature resistant PET is also used to manufacture housings for medical devices and equipment that require high-temperature sterilization. Its chemical stability and biocompatibility make it a preferred material in the medical industry. In the optical field, high-temperature PET, due to its transparency and excellent optical properties, is often used as optical films, display screen protective films, etc., especially in optical components that need to withstand high-temperature processing. In short, due to its excellent physical and chemical properties, high-temperature PET is widely used in fields requiring high temperature resistance, high mechanical strength, and chemical corrosion resistance, covering a wide range of industries from electronics and electrical, automotive, packaging, medical equipment, to optical devices.

[0003] The prior art records a variety of different high-temperature resistant polyester materials and their application examples of preparation.

[0004] For example, CN 109054311 B discloses a high-temperature-resistant polyester film and a preparation method thereof. The film includes upper and lower surface layers and a core layer located in the middle. The upper and lower surface layers have the same composition, which includes the following weight components: 90-97% PEN chips, 0-7% PET chips, and 3% PET opening agent masterbatch; the core layer includes the following weight components: 50-70% PEN chips, 25-40% PET chips, and 5-10% modified montmorillonite masterbatch; the modified montmorillonite masterbatch is mainly made of the following components in weight percentage: 10% modified montmorillonite and 90% PET. This prior art uses PEN to improve the mechanical strength, light transmittance, and heat resistance of the film, uses a small amount of PET to reduce the cost through melt blending, and improves the crystallization properties of the two by adding modified montmorillonite.

[0005] CN 105778442 B discloses a high-temperature-resistant antistatic PET material and a preparation method thereof, which is composed of the following components in weight parts: polyethylene terephthalate resin 60-70 parts; polymeric polyol 15-20 parts, nano-silver modified dihydroxy polydiphenyl siloxane 5-10 parts, toughening agent 3-10 parts; antistatic agent 10-15 parts; antioxidant 0.5-3 parts; dispersing agent 4-8 parts; light shielding agent 1-5 parts. This prior art adds polymeric polyol and nano-silver modified dihydroxy polydiphenyl siloxane, and utilizes the synergistic effect of the two to make the prepared PET material not only have good antistatic properties, but also maintain good mechanical properties at high temperatures.

[0006] CN 117024806 B discloses a preparation method of a high-temperature-resistant reinforced PET release film, which includes the following steps in weight parts: taking 20-35 parts of PET, adding 5-10 parts of dimethylamide, heating and stirring to obtain mixture A; mixing NaOH solution, cerium-barium co-modified zirconium dioxide particles, and sodium hexametaphosphate to obtain mixture B; adding 0.5-1 parts of plasticizer and 1-5 parts of mixture B to mixture A, stirring at a speed of 1500-2000 rpm for 2 h; ultrasonic dispersion for 25-40 min; standing for 24-48 h to degas; casting onto a horizontal glass plate, drying at 130-170°C for 12-24 h to obtain the high-temperature-resistant reinforced PET release film. This prior art adds cerium-barium co-modified zirconium dioxide particles, and the synergistic effect of cerium and barium can promote the formation of stable clusters or particles of zirconium dioxide particles, prevent the growth of zirconium dioxide crystal grains and the diffusion of grain boundaries, and thus improve the thermal stability and oxidation resistance of the material, effectively increase the tensile strength and hardness of the material, and thus improve the durability and mechanical properties.

[0007] In the prior art polyester material, the high temperature resistance is usually improved by adding a modifying material. Although the modification process can reduce the agglomeration of the modifying material and improve its dispersibility, good dispersibility does not mean that the modifying material can be uniformly distributed in the melt. Especially in the case of small amount of modifying ingredients, due to the poor fluidity of the melt, a long time of heating and stirring is needed to make the small amount of modifying material uniformly dispersed in the molten polyester. However, long time high temperature stirring will reduce the crystallinity of the polyester, so that it is difficult to produce products with uniform quality in the process. SUMMARY

[0008] The technical problem to be solved by the present application is to provide a high temperature resistant PET functional masterbatch and a preparation method thereof, so as to reduce or avoid the problems mentioned above.

[0009] To solve the above technical problems, the present application provides a high temperature resistant PET functional masterbatch, which is prepared from the following raw materials by weight: 50-100 parts by weight of terephthalic acid, 20-45 parts by weight of ethylene glycol, 5-10 parts by weight of dimethyl 2,6-naphthalene dicarboxylate, 0.02-0.04 parts by weight of acetic anhydride, 0.03-0.05 parts by weight of acetone, 0.005-0.01 parts by weight of antimony dioxide, 0.01-0.03 parts by weight of triethyl phosphate, 0.01-0.03 parts by weight of sodium dodecyl benzene sulfonate, 0.05-0.10 parts by weight of 2-hydroxy-4-(3-triethoxysilane propoxy) benzophenone, 0.10-0.15 parts by weight of ethanol, and 0.01-0.03 parts by weight of cellulose acetate.

[0010] Preferably, the cellulose acetate is commercially available powder with an acetyl content of 37% to 40%.

[0011] The application further provides a preparation method of the high-temperature-resistant PET functional masterbatch, comprising the following steps: uniformly mixing 0.02-0.04 parts by weight of acetic anhydride and 0.03-0.05 parts by weight of acetone, then adding 0.005-0.01 parts by weight of antimony dioxide, uniformly mixing and reacting for more than 30 minutes to prepare an A solution for standby; uniformly mixing 0.01-0.03 parts by weight of sodium dodecylbenzenesulfonate, 0.05-0.10 parts by weight of 2-hydroxy-4-(3-triethoxysilylpropoxy) benzophenone, 0.10-0.15 parts by weight of ethanol and 0.01-0.03 parts by weight of cellulose acetate, heating to 50 DEG C and standing for hydrolysis for more than 1 hour to prepare a B solution for standby; adding 50-100 parts by weight of terephthalic acid, 20-45 parts by weight of ethylene glycol and 5-10 parts by weight of dimethyl 2,6-naphthalene dicarboxylate into an esterification tank and uniformly mixing, then uniformly mixing the A solution and adding into the esterification tank for reaction; the reaction temperature is 180-260 DEG C, the gauge pressure is 0.2-0.3 MPa, when the water output reaches 1200 ml, the pressure is released to normal pressure, the reaction product is filtered and input into a polycondensation tank; then the B solution is uniformly mixed and added into the polycondensation tank, 0.01-0.03 parts by weight of triethyl phosphate is added into the polycondensation tank, and the normal pressure is stirred for 30-60 minutes, the temperature is 230-280 DEG C, the pressure is below 100 Pa, and the reaction is carried out for 3-5 hours; the reaction product in the polycondensation tank is extruded and sliced; the slice is input into a vacuum drying tank and dried for more than 10 hours to obtain the high-temperature-resistant PET functional masterbatch.

[0012] Preferably, the drying temperature of the vacuum drying tank is 230-250 DEG C, and the pressure is below 100 Pa.

[0013] The application can be relatively easily dispersed into the masterbatch without affecting the crystallinity of the polyester, so that excellent high-temperature-resistant performance can be obtained. DETAILED DESCRIPTION

[0014] In order to have a clearer understanding of the technical features, objectives and effects of the application, the specific embodiments of the application are described in detail.

[0015] In view of the problems in the prior art, the application provides a high-temperature-resistant PET functional masterbatch and a preparation method thereof, and the high-temperature-resistant PET functional masterbatch can keep its performance unchanged at a high temperature and can be applied to the application fields of electronic and electrical appliances, automobiles, packaging, machinery, medical devices and optics.

[0016] In one specific embodiment, the high-temperature-resistant PET functional masterbatch of the present application can be used as raw material to prepare high-temperature-resistant PET film or parts, or can be added to ordinary polyester raw material as a functional additive to prepare polyester products with certain high-temperature-resistant requirements, or can be used as a high-temperature-resistant functional layer in a multi-layer polyester film to improve the high-temperature-resistant performance of the multi-layer polyester film.

[0017] Specifically, the high-temperature-resistant PET functional masterbatch of the present application is prepared from the following raw materials in the following proportions by weight: 50-100 parts by weight of terephthalic acid, 20-45 parts by weight of ethylene glycol, 5-10 parts by weight of dimethyl 2,6-naphthalene dicarboxylate, 0.02-0.04 parts by weight of acetic anhydride, 0.03-0.05 parts by weight of acetone, 0.005-0.01 parts by weight of antimony dioxide, 0.01-0.03 parts by weight of triethyl phosphate, 0.01-0.03 parts by weight of sodium dodecyl benzene sulfonate, 0.05-0.10 parts by weight of 2-hydroxy-4-(3-triethoxysilyl propoxy) benzophenone, 0.10-0.15 parts by weight of ethanol, and 0.01-0.03 parts by weight of cellulose acetate. The cellulose acetate is commercially available powder with an acetyl content of 37%-40%.

[0018] The preparation method of the high-temperature-resistant PET functional masterbatch of the present application comprises the following steps:

[0019] Mix 0.02-0.04 parts by weight of acetic anhydride and 0.03-0.05 parts by weight of acetone uniformly, then add 0.005-0.01 parts by weight of antimony dioxide, mix uniformly, and react for 30 minutes or more to prepare A solution for standby.

[0020] Mix 0.01-0.03 parts by weight of sodium dodecyl benzene sulfonate, 0.05-0.10 parts by weight of 2-hydroxy-4-(3-triethoxysilyl propoxy) benzophenone, 0.10-0.15 parts by weight of ethanol, and 0.01-0.03 parts by weight of cellulose acetate uniformly, heat to 50°C, and stand for hydrolysis for 1 hour or more to prepare B solution for standby.

[0021] Add 50-100 parts by weight of terephthalic acid, 20-45 parts by weight of ethylene glycol, and 5-10 parts by weight of dimethyl 2,6-naphthalene dicarboxylate to an esterification tank and mix uniformly, then add A solution after stirring uniformly, and react in the esterification tank. The reaction temperature is 180-260°C, the gauge pressure is 0.2-0.3 MPa, and when the water output reaches 1200 ml, the pressure is released to normal pressure, the reaction product is filtered and input into a polycondensation tank.

[0022] Then the B solution is stirred and added to the polycondensation tank, and 0.01-0.03 parts by weight of triethyl phosphate is added to the polycondensation tank, stirred at normal pressure for 30-60 minutes, and reacted at a temperature of 230-280°C and a pressure of 100 Pa or less for 3-5 hours. The reaction product in the polycondensation tank is extruded and sliced.

[0023] The slices are input into a vacuum drying tank to dry for 10 hours or more to obtain the high-temperature-resistant PET functional masterbatch of the present application. The drying temperature of the vacuum drying tank is 230-250°C, and the pressure is 100 Pa or less.

[0024] In the A solution, a part of the antimony acetate can form a suspension, which can be fully dispersed in the system during esterification and can also act as a catalyst for multi-system esterification, and can improve the high-temperature resistance of the subsequent polymerization product. In the B solution, 2-hydroxy-4-(3-triethoxysilane propoxy) benzophenone can be hydrolyzed to obtain silanol in an alkaline environment composed of sodium dodecylbenzenesulfonate and ethanol, and then polymerized into a polysiloxane chain, which is then dispersed in the cellulose acetate emulsion to form a grid-shaped dispersion system. During the polycondensation reaction, the dispersed polysiloxane chain can firmly connect PET and PEN, thereby greatly improving the high-temperature resistance of the functional masterbatch. A small amount of unhydrolyzed 2-hydroxy-4-(3-triethoxysilane propoxy) benzophenone can still play a role in preventing ultraviolet radiation, further improving the anti-aging performance of the functional masterbatch.

[0025] Example 1

[0026] 0.02 parts by weight of acetic anhydride and 0.03 parts by weight of acetone are uniformly mixed, then 0.005 parts by weight of antimony dioxide is added, and uniformly mixed and reacted for 30 minutes to prepare the A solution for standby.

[0027] 0.01 parts by weight of sodium dodecylbenzenesulfonate, 0.05 parts by weight of 2-hydroxy-4-(3-triethoxysilane propoxy) benzophenone, 0.10 parts by weight of ethanol, and 0.01 parts by weight of cellulose acetate are uniformly mixed, heated to 50°C, and hydrolyzed for 1 hour to prepare the B solution for standby.

[0028] 50 parts by weight of terephthalic acid, 20 parts by weight of ethylene glycol, and 5 parts by weight of dimethyl 2,6-naphthalene dicarboxylate are added to the esterification tank and uniformly mixed, then the A solution is stirred and added to the esterification tank for reaction. The reaction temperature is 180°C, the gauge pressure is 0.2 MPa, and when the water output reaches 1200 ml, the pressure is released to normal pressure. The reaction product is filtered and input into the polycondensation tank.

[0029] Then the B solution is stirred uniformly and added to the polycondensation tank, and 0.01 parts by weight of triethyl phosphate is added to the polycondensation tank, stirred at normal pressure for 30 minutes, and reacted at a temperature of 230°C and a pressure of 100 Pa for 3 hours. The reaction product in the polycondensation tank is extruded and sliced.

[0030] The slices are input into a vacuum drying tank to dry for 10 hours to obtain the high-temperature-resistant PET functional masterbatch of the application. The drying temperature of the vacuum drying tank is 230°C, and the pressure is 100 Pa.

[0031] The prepared high-temperature-resistant PET functional masterbatch is mixed with ordinary film PET chips according to 70 wt%, 85 wt%, and 100 wt% of the total mass of the film layer, respectively, and then melt-extruded, die-casted, transversely and longitudinally stretched, cold-formed, wound, and cut to prepare polyester films with a single-layer structure. The width of the prepared film is 1500 mm, and the thickness is 30 μm.

[0032] The performance parameters of the three polyester films with a single-layer structure prepared in Example 1 are measured, wherein the tensile strength at 25°C is 285 MPa, 293 MPa, and 297 MPa, respectively; the transverse heat shrinkage rate at 120°C for 30 minutes is less than 0.01%; the transverse heat shrinkage rate at 200°C for 30 minutes is 0.06%, 0.05%, and 0.04%, respectively; the light transmittance is 93.1%, 93.2%, and 93.3%, respectively; and the tensile strength at 300°C is 167 MPa, 170 MPa, and 174 MPa, respectively.

[0033] Example 2

[0034] 0.03 parts by weight of acetic anhydride and 0.04 parts by weight of acetone are uniformly mixed, and then 0.008 parts by weight of antimony dioxide is added and uniformly mixed and reacted for 40 minutes to prepare an A solution for standby.

[0035] 0.02 parts by weight of sodium dodecylbenzenesulfonate, 0.08 parts by weight of 2-hydroxy-4-(3-triethoxysilylpropoxy) benzophenone, 0.12 parts by weight of ethanol, and 0.02 parts by weight of cellulose acetate are uniformly mixed, heated to 55°C, and hydrolyzed at room temperature for 1.5 hours to prepare a B solution for standby.

[0036] 80 parts by weight of terephthalic acid, 35 parts by weight of ethylene glycol, and 8 parts by weight of dimethyl 2,6-naphthalene dicarboxylate are added to an esterification tank and uniformly mixed, and then the A solution is stirred uniformly and added to the esterification tank for reaction. The reaction temperature is 220°C, the gauge pressure is 0.25 MPa, and when the water output reaches 1200 ml, the pressure is released to normal pressure. The reaction product is filtered and input into a polycondensation tank.

[0037] Then the B solution is stirred uniformly and added into the polycondensation tank, 0.02 parts by weight of triethyl phosphate is added into the polycondensation tank, stirred at normal pressure for 45 minutes, the temperature is 255°C, the pressure is 90 Pa, and the reaction is carried out for 4 hours. The reaction product in the polycondensation tank is extruded and sliced.

[0038] The slices are input into a vacuum drying tank to dry for 11 hours to obtain the high-temperature-resistant PET functional masterbatch of the application. The drying temperature of the vacuum drying tank is 240°C, and the pressure is 90 Pa.

[0039] The prepared high-temperature-resistant PET functional masterbatch is mixed with ordinary film PET slices according to 70 wt%, 85 wt%, and 100 wt% of the total mass of the film layer respectively, and then melt-extruded, die-casted, transversely and longitudinally stretched, cold-formed, wound and cut to prepare polyester films with a single-layer structure. The width of the prepared film is 3000 mm, and the thickness is 100 μm.

[0040] The performance parameters of the three polyester films with a single-layer structure prepared in Example 2 are measured, wherein the tensile strength at 25°C is 287 MPa, 297 MPa, and 301 MPa respectively; the transverse heat shrinkage rate at 120°C for 30 minutes is less than 0.01%; the transverse heat shrinkage rate at 200°C for 30 minutes is 0.05%, 0.04%, and 0.03% respectively; the light transmittance is 92.7%, 92.8%, and 92.9% respectively; and the tensile strength at 300°C is 177 MPa, 176 MPa, and 179 MPa respectively.

[0041] Example 3

[0042] 0.04 parts by weight of acetic anhydride and 0.05 parts by weight of acetone are uniformly mixed, then 0.003 parts by weight of antimony dioxide is added, uniformly mixed, and reacted for 50 minutes to prepare an A solution for standby.

[0043] 0.03 parts by weight of sodium dodecylbenzenesulfonate, 0.10 parts by weight of 2-hydroxy-4-(3-triethoxysilylpropoxy) benzophenone, 0.15 parts by weight of ethanol, and 0.03 parts by weight of cellulose acetate are uniformly mixed, heated to 60°C, and hydrolyzed for 2 hours to prepare a B solution for standby.

[0044] 100 parts by weight of terephthalic acid, 45 parts by weight of ethylene glycol, and 10 parts by weight of dimethyl 2,6-naphthalene dicarboxylate are added into an esterification tank and uniformly mixed, then the A solution is stirred uniformly and added into the esterification tank for reaction. The reaction temperature is 260°C, the gauge pressure is 0.3 MPa, when the water output reaches 1200 ml, the pressure is released to normal pressure, the reaction product is filtered and input into a polycondensation tank.

[0045] Then the B solution was stirred evenly and added into the polycondensation tank, 0.03 parts by weight of triethyl phosphate was added into the polycondensation tank, stirred at normal pressure for 60 minutes, the temperature was 280°C, the pressure was 80 Pa, and the reaction was carried out for 5 hours. The reaction product in the polycondensation tank was extruded and sliced.

[0046] The slices were input into a vacuum drying tank and dried for 12 hours to obtain the high-temperature-resistant PET functional masterbatch of the application. The drying temperature of the vacuum drying tank was 250°C, and the pressure was 80 Pa.

[0047] The prepared high-temperature-resistant PET functional masterbatch was mixed with ordinary film PET slices according to 70 wt%, 85 wt%, and 100 wt% of the total mass of the film layer, respectively, and then melt-extruded, die-casted, transversely and longitudinally stretched, cooled and shaped, and wound and cut to prepare polyester films with a single-layer structure. The width of the prepared film was 5000 mm, and the thickness was 250 μm.

[0048] The performance parameters of the three polyester films with a single-layer structure prepared in Example 3 were measured, wherein the tensile strength at 25°C was 301 MPa, 302 MPa, and 305 MPa, respectively; the transverse heat shrinkage rate at 120°C for 30 minutes was less than 0.01%; the transverse heat shrinkage rate at 200°C for 30 minutes was 0.02%, 0.01%, and 0.03%, respectively; the light transmittance was 94.2%, 94.3%, and 94.1%, respectively; and the tensile strength at 300°C was 171 MPa, 177 MPa, and 183 MPa, respectively.

[0049] Comparative experiments were carried out by adjusting the proportions of some raw materials according to the preparation process parameters of Examples 1-3, respectively.

[0050] Comparative Example 1

[0051] The functional masterbatch was prepared according to the preparation process parameters of Example 1. In the preparation process, the A solution was not used, and 0.005 parts by weight of antimony acetate was used instead of the A solution. The 2-hydroxy-4-(3-triethoxysilylpropoxy) benzophenone was not added in the preparation of the B solution. The remaining process parameters and the weight parts of the raw materials were the same as those of Example 1.

[0052] The prepared functional masterbatch was mixed with ordinary film PET slices according to 70 wt%, 85 wt%, and 100 wt% of the total mass of the film layer, respectively, and then melt-extruded, die-casted, transversely and longitudinally stretched, cooled and shaped, and wound and cut to prepare polyester films with a single-layer structure.

[0053] The performance parameters of the three single-layer polyester films prepared in Comparative Example 1 were measured, wherein the tensile strength at 25℃ was 288 MPa, 209 MPa, and 213 MPa, respectively; the transverse heat shrinkage at 120℃ for 30 minutes was 6.7%, 6.6%, and 6.5%, respectively; the transverse heat shrinkage at 200℃ for 30 minutes was 10.3%, 10.0%, and 9.8%, respectively; the light transmittance was 82.3%, 82.4%, and 82.1%, respectively; and the tensile strength at 300℃ was 12 MPa, 13 MPa, and 15 MPa, respectively.

[0054] Comparative Example 2

[0055] The functional masterbatch was prepared according to the preparation process parameters of Example 2. During the preparation process, the A solution was not used, and 0.008 parts by weight of antimony acetate was used to replace the A solution in the adding step. The 2-hydroxy-4-(3-triethoxysilyl propoxy) benzophenone and the cellulose acetate were not added in the preparation of the B solution. The other process parameters and the raw material parts by weight were the same as those of Example 2.

[0056] The prepared functional masterbatch was mixed with the ordinary film PET chip according to 70 wt%, 85 wt%, and 100 wt% of the total mass of the film layer, respectively, and then melt-extruded, die-casted, transversely and longitudinally stretched, cooled and shaped, and wound and cut to prepare the single-layer polyester film.

[0057] The performance parameters of the three single-layer polyester films prepared in Comparative Example 2 were measured, wherein the tensile strength at 25℃ was 219 MPa, 218 MPa, and 221 MPa, respectively; the transverse heat shrinkage at 120℃ for 30 minutes was 2.5%, 2.8%, and 2.7%, respectively; the transverse heat shrinkage at 200℃ for 30 minutes was 3.3%, 3.4%, and 3.8%, respectively; the light transmittance was 87.8%, 87.3%, and 87.2%, respectively; and the tensile strength at 300℃ was 42 MPa, 43 MPa, and 45 MPa, respectively.

[0058] Comparative Example 3

[0059] The functional masterbatch was prepared according to the preparation process parameters of Example 3. During the preparation process, the A solution was not used, and 0.01 parts by weight of antimony acetate was used to replace the A solution in the adding step. The 2-hydroxy-4-(3-triethoxysilyl propoxy) benzophenone and the sodium dodecyl benzene sulfonate were not added in the preparation of the B solution. The other process parameters and the raw material parts by weight were the same as those of Example 3.

[0060] As example 3, the prepared functional masterbatch was mixed with PET chip for common film according to 70 wt%, 85 wt%, 100 wt% of the total mass of the film layer respectively, and then melt extruded, die cast, transversely and longitudinally stretched, cooled and shaped, wound and cut to prepare polyester film with single layer structure.

[0061] The performance parameters of the three polyester films with single layer structure prepared in Comparative Example 3 were measured, wherein the tensile strength at 25℃ was 188 MPa, 191 MPa, 195 MPa respectively; the transverse heat shrinkage at 120℃ for 30 minutes was 5.5%, 5.2%, 4.6% respectively; the transverse heat shrinkage at 200℃ for 30 minutes was 7.9%, 7.7%, 7.6% respectively; the light transmittance was 83.2%, 83.3%, 83.0% respectively; the tensile strength at 300℃ was 20 MPa, 22 MPa, 24 MPa respectively.

[0062] According to the experimental data, the inventors believe that, due to the use of the optimized esterification dispersion catalytic system, and the addition of the grid-shaped polysiloxane chain at the beginning of the relatively small molecular chain polycondensation stage, the polyester can be relatively easily dispersed in the masterbatch, and the crystallinity of the polyester is not affected, so that excellent high temperature resistance can be obtained. Further experiments show that the examples 1-3 still do not appear obvious shrinkage after baking at 300℃ for 30 minutes. And in the accelerated aging test, the average number of color spots of examples 1-3 for 6 months is much less than that of comparative examples 1-3 (less than 10%), indicating that the polyester film of the present application has excellent anti-aging performance, and also shows excellent corrosion resistance and stable quality.

[0063] Those skilled in the art should understand that although the present application is described in the form of multiple embodiments, not every embodiment contains only one independent technical solution. The description in the specification is only for the sake of clarity, those skilled in the art should understand the specification as a whole and understand the technical solutions involved in each embodiment as a way of combining different embodiments to understand the protection scope of the present application.

[0064] The above description is only a specific implementation of the present application, and is not intended to limit the scope of the present application. Any equivalent changes, modifications and combinations made by those skilled in the art without departing from the concept and principles of the present application shall fall within the scope of the present application.

Claims

1. A high-temperature-resistant PET functional masterbatch, which is prepared from the following raw materials in parts by weight: 50-100 parts by weight of terephthalic acid, 20-45 parts by weight of ethylene glycol, 5-10 parts by weight of dimethyl 2,6-naphthalene dicarboxylate, 0.02-0.04 parts by weight of acetic anhydride, 0.03-0.05 parts by weight of acetone, 0.005-0.01 parts by weight of antimony dioxide, 0.01-0.03 parts by weight of triethyl phosphate, 0.01-0.03 parts by weight of sodium dodecyl benzene sulfonate, 0.05-0.10 parts by weight of 2-hydroxy-4-(3-triethoxysilyl propoxy) benzophenone, 0.10-0.15 parts by weight of ethanol, and 0.01-0.03 parts by weight of cellulose acetate.

2. The functional masterbatch according to claim 1, characterized in that The cellulose acetate is in the form of a powder with an acetyl content of 37%-40%.

3. A method for preparing a high-temperature-resistant PET functional masterbatch, comprising the following steps: 0.02-0.04 parts by weight of acetic anhydride and 0.03-0.05 parts by weight of acetone are uniformly mixed, then 0.005-0.01 parts by weight of antimony dioxide is added, and the mixture is uniformly mixed and reacted for more than 30 minutes to prepare an A solution for standby; 0.01-0.03 parts by weight of sodium dodecyl benzene sulfonate, 0.05-0.10 parts by weight of 2-hydroxy-4-(3-triethoxysilyl propoxy) benzophenone, 0.10-0.15 parts by weight of ethanol, and 0.01-0.03 parts by weight of cellulose acetate are uniformly mixed, heated to 50°C, and left to hydrolyze for more than 1 hour to prepare a B solution for standby; 50-100 parts by weight of terephthalic acid, 20-45 parts by weight of ethylene glycol, and 5-10 parts by weight of dimethyl 2,6-naphthalene dicarboxylate are uniformly mixed in an esterification tank, then the A solution is uniformly stirred and added to the esterification tank for reaction; the reaction temperature is 180-260°C, the gauge pressure is 0.2-0.3 MPa, and when the water output reaches 1200 ml, the pressure is released to normal pressure, the reaction product is filtered and input into a polycondensation tank; then the B solution is uniformly stirred and added to the polycondensation tank, 0.01-0.03 parts by weight of triethyl phosphate is added to the polycondensation tank, and the mixture is stirred at normal pressure for 30-60 minutes, the temperature is 230-280°C, the pressure is below 100 Pa, and the mixture is reacted for 3-5 hours; the reaction product in the polycondensation tank is extruded and sliced; the slices are input into a vacuum drying tank and dried for more than 10 hours to obtain the high-temperature-resistant PET functional masterbatch.

4. The method of claim 3, wherein, The drying temperature of the vacuum drying tank is 230-250°C, and the pressure is below 100 Pa.