Antistatic PVC calendering film and method for producing the same

Abstract

The application relates to the technical field of anti-static PVC material research and development, and discloses an anti-static PVC calendering film and a preparation method thereof, specifically: quaternary ammonium organosilicon modified PVC is prepared by grafting secondary amine quaternary ammonium linear organosilicon compounds and secondary amine quaternary ammonium cage organosilicon compounds onto PVC molecular chains through a nucleophilic substitution reaction of secondary amine-chlorine; sulfonated conductive carbon black fillers are prepared by functionally modifying conductive carbon black fillers with 1,3-propane sulfonic acid lactone; in the presence of a heat stabilizer, the quaternary ammonium organosilicon modified PVC and the sulfonated conductive carbon black fillers are first mixed and milled, the ion bonding type interface compatibility of the conductive carbon black fillers and the PVC matrix is realized through electrostatic adsorption, then PVC resin is compounded, and finally, the PVC calendering film is prepared through a calendering forming process; the film product has an anti-static effect and shows strong and tough balanced characteristics.

Description

Technical Field

[0001] This invention relates to the field of antistatic PVC material research and development technology, specifically to antistatic PVC calendered film and its preparation method. Background Technology

[0002] PVC calendered film is a polymer film material made from polyvinyl chloride (PVC) resin through high-speed mixing, open milling and calendering processes. Due to its advantages such as high cost-effectiveness, wear resistance, chemical corrosion resistance and good flame retardancy, it is widely used in many fields such as packaging, construction, electronics, medical and home decoration.

[0003] However, PVC calendered film has high molecular insulation properties (its volume resistivity is typically as high as 10). 14 -10 16 During calendering and subsequent processing, transportation, and use, electrostatic discharge (ESD) can easily lead to charge transfer and static electricity accumulation due to friction and contact separation. This static electricity not only causes dust accumulation and damage to the film surface, but also triggers process failures such as film adhesion and misalignment in high-speed production lines. In the electronics field, ESD can cause component breakdown; in flammable environments, it poses a serious ignition hazard.

[0004] Introducing conductive fillers into PVC materials is one of the important technical paths to achieve antistatic modification. However, the interfacial compatibility between inorganic conductive fillers (such as graphene, carbon nanotubes, carbon black, etc.) and organic PVC cotton matrix is ​​limited. Direct addition can easily lead to agglomeration or interfacial defects, which significantly degrades the performance of the material.

[0005] Studies have found that due to the large number of strongly polar C-Cl bonds in the PVC molecular chain, the strong intermolecular forces result in defects such as high brittleness, poor toughness, and insufficient ductility, making the material prone to cracking during the calendering process. Currently, the industry often uses small-molecule plasticizers such as phthalates (e.g., DOP, DBP, DIBP) to improve its flexibility. However, these small-molecule plasticizers not only have long-term stability problems such as easy migration, volatility, and precipitation, but also cause the physical and mechanical properties of PVC calendered films to degrade over time, and may also pose environmental and health risks.

[0006] Existing technologies have reported methods to toughen PVC by introducing flexible segments into the PVC molecular chain. However, while the introduction of flexible segments can improve impact toughness, it can significantly reduce the material's mechanical strength (such as tensile strength). Therefore, achieving a balance between strength and toughness in PVC while maintaining its mechanical strength is of great significance for expanding its engineering application value. Summary of the Invention

[0007] This invention uses conductive carbon black as an antistatic filler and, through molecular design, develops quaternized linear organosilicon compounds with flexible structures and quaternized cage-type organosilicon compounds with both rigid and flexible structures. These compounds are introduced into the PVC molecular chain through chemical bonding. On the one hand, the flexible structure achieves the technical effect of toughening; on the other hand, the rigid structure maintains the mechanical strength of the material; and thirdly, the quaternary ammonium structure utilizes electrostatic adsorption to achieve ion-bonded interface compatibility between the conductive carbon black filler and the PVC matrix. The resulting PVC calendered film product has an antistatic effect and exhibits a balance of strength and toughness.

[0008] An antistatic PVC calendered film comprises the following raw materials in parts by weight:

[0009] 30-45 parts PVC resin;

[0010] 45-60 parts of quaternized organosilicon-modified PVC;

[0011] 8-12 parts sulfonated conductive carbon black filler;

[0012] 0.5-3 parts heat stabilizer;

[0013] Among them, the quaternized organosilicon modified PVC is prepared by grafting secondary amine quaternized linear organosilicon compounds and secondary amine quaternized cage organosilicon compounds onto the PVC molecular chain through a nucleophilic substitution reaction of secondary amine-chlorine.

[0014] Sulfonated conductive carbon black filler is prepared by grafting 1,3-propanesulfonic acid lactone onto the surface of hydroxylated conductive carbon black filler via a sulfonyl lactone-hydroxy ring-opening reaction, followed by alkali neutralization treatment.

[0015] Preferably, the formulation of the quaternized organosilicon modified PVC is: 86-96 wt% polyvinyl chloride resin, 2-7 wt% secondary amine quaternized linear organosilicon compound and 2-7 wt% secondary amine quaternized cage-type organosilicon compound.

[0016] Preferably, the mass ratio of 1,3-propanesulfonic acid lactone to hydroxylated conductive carbon black filler in the sulfonated conductive carbon black filler is (0.3-1):10.

[0017] Preferably, the particle size of the hydroxylated conductive carbon black filler is 20-30 nm.

[0018] A method for preparing an antistatic PVC calendered film includes the following steps:

[0019] Step 1: By conducting a nucleophilic substitution reaction between the secondary amine functional groups in the secondary amine quaternized linear organosilicon compound and the secondary amine quaternized cage organosilicon compound and the chlorine functional groups on the PVC molecular chain, the grafting modification treatment of PVC resin by the secondary amine quaternized linear organosilicon compound and the secondary amine quaternized cage organosilicon compound is achieved, resulting in quaternized organosilicon modified PVC.

[0020] Step 2: The hydroxyl functional groups on the surface of the hydroxylated conductive carbon black filler undergo a ring-opening reaction with 1,3-propanesulfonic acid lactone to form sulfonic acid groups, and then the filler is neutralized with sodium hydroxide to obtain sulfonated conductive carbon black filler.

[0021] Step 3: In the presence of a heat stabilizer, quaternized organosilicon-modified PVC and sulfonated conductive carbon black filler are first mixed. The sulfonate groups in the sulfonated conductive carbon black filler and the quaternary ammonium salt groups in the quaternized organosilicon-modified PVC undergo electrostatic adsorption, achieving ion-bonded interfacial compatibility between the conductive carbon black filler and the PVC matrix. Then, PVC resin is compounded and calendered to obtain an antistatic PVC calendered film.

[0022] Preferably, the method for preparing the secondary amine quaternized linear organosilicon compound is as follows:

[0023] An addition reaction is carried out between the Si-H functional group of 1,1,3,3,5,5,7,7-octamethyltetrasiloxane and the alkenyl functional group of vinyldimethylethoxysilane, and the molar ratio of 1,1,3,3,5,5,7,7-octamethyltetrasiloxane to vinyldimethylethoxysilane is controlled to be 1:2.01-2.05, to generate a diethoxy linear silane monomer;

[0024] The addition reaction between the -NH2 functional group of (3-aminopropyl)dimethylethoxysilane and the α,β-alkenyl functional group of acryloyloxyethyltrimethylammonium chloride, with the molar ratio of (3-aminopropyl)dimethylethoxysilane to acryloyloxyethyltrimethylammonium chloride controlled at 1:0.95-0.99, yields a secondary aminoquaternized ethoxysilane monomer.

[0025] A secondary amino-quaternized linear organosilicon compound is generated by a condensation reaction between the silyl ethoxy group of a diethoxy linear silane monomer and the silyl ethoxy group of a secondary amino-quaternized ethoxy silane monomer, with the molar ratio of the diethoxy linear silane monomer to the secondary amino-quaternized ethoxy silane monomer controlled at 1:2.01-2.05.

[0026] Preferably, the preparation method of the secondary amine quaternized cage-type organosilicon compound is as follows:

[0027] The addition reaction between the Si-H functional group of hexamethyldihydroPOSS and the alkenyl functional group of vinyldimethylethoxysilane is carried out, and the molar ratio of hexamethyldihydroPOSS to vinyldimethylethoxysilane is controlled to be 1:2.01-2.05, to generate diethoxycage silane monomer.

[0028] A secondary amino-quaternized cage-type organosilicon compound is generated by a condensation reaction between the silyl ethoxy group of the diethoxy cage-type silane monomer and the silyl ethoxy group of the secondary amino-quaternized ethoxysilane monomer, and by controlling the molar ratio of the diethoxy cage-type silane monomer to the secondary amino-quaternized ethoxysilane monomer to be 1:2.01-2.05.

[0029] Preferably, the preparation method of hexamethyldihydroPOSS is as follows: by acid-catalyzing the hydrolysis and condensation reaction of methyltrimethoxysilane and trimethoxysilane, and controlling the molar ratio of methyltrimethoxysilane and trimethoxysilane to be 3.01-3.05:1, hexamethyldihydroPOSS is generated.

[0030] Beneficial effects:

[0031] This invention uses 1,1,3,3,5,5,7,7-octamethyltetrasiloxane (flexible linear structure) or hexamethyldihydroPOSS (rigid cage structure) as raw materials. First, it undergoes an addition reaction with vinyldimethylethoxysilane to introduce a silane ethoxy group. Then, it undergoes a condensation reaction with the silane ethoxy group of a secondary amino quaternized ethoxysilane monomer (obtained by an addition reaction between (3-aminopropyl)dimethylethoxysilane and acryloyloxyethyltrimethylammonium chloride) to form a flexible siloxane chain and introduce a quaternary ammonium structure, thus obtaining a quaternized linear organosilicon compound with a flexible structure (secondary amino quaternized linear organosilicon compound) or a quaternized cage organosilicon compound with both rigid and flexible structures (secondary amino quaternized cage organosilicon compound).

[0032] Quaternized organosilicon modified PVC is prepared by grafting secondary amine quaternized linear organosilicon compounds and / or secondary amine quaternized cage organosilicon compounds onto the PVC molecular chain via a nucleophilic substitution reaction of secondary amine-chlorine.

[0033] Sulfonated conductive carbon black filler was prepared by functional modification of conductive carbon black filler with 1,3-propanesulfonate lactone.

[0034] In the presence of a heat stabilizer, quaternized organosilicon-modified PVC and sulfonated conductive carbon black filler are first mixed and then the conductive carbon black filler and the ion-bonded interface of the PVC matrix are made compatible through electrostatic adsorption. Then, PVC resin is compounded and an antistatic PVC calendered film is obtained through a calendering process.

[0035] The experimental results show that the PVC calendered film product prepared by this invention has an antistatic effect.

[0036] The antistatic PVC calendered film prepared by the present invention using secondary amine quaternized linear organosilicon compounds and secondary amine quaternized cage-type organosilicon compounds has both excellent longitudinal tensile strength and resistance to pendulum impact energy, exhibiting a strong and tough balance. Detailed Implementation

[0037] Example 1:

[0038] The preparation of secondary amine quaternized linear organosilicon compounds includes the following processes:

[0039] (1) Preparation of diethoxy linear silane monomer: The diethoxy linear silane monomer is generated by the addition reaction of the Si-H functional group of 1,1,3,3,5,5,7,7-octamethyltetrasiloxane with the alkenyl functional group of vinyldimethylethoxysilane, and the molar ratio of 1,1,3,3,5,5,7,7-octamethyltetrasiloxane to vinyldimethylethoxysilane is controlled to be 1:2.04. The preparation steps are as follows: 2.8g of 1,1,3,3,5,5,7,7-octamethyltetrasiloxane (CAS No. 100) is added to the diethoxy linear silane monomer. 0-05-1) and 30 mL of anhydrous N,N-dimethylformamide were added to a three-necked flask and stirred at room temperature until completely dissolved. Then, under nitrogen protection, 3.4 mL of vinyldimethylethoxysilane (CAS No. 5356-83-2) and 2 drops of caster catalyst (containing 2% Pt) were added dropwise to the three-necked flask. The mixture was heated to 80 °C and stirred for 5 h. After cooling to room temperature, 10 mg of triphenylphosphine was added, and the mixture was stirred for 1 h. The mixture was then filtered, and the filtrate was collected, evaporated under reduced pressure, and dried to obtain a diethoxy linear silane monomer with the following chemical structure:

[0040] ;

[0041] (2) Preparation of secondary amino quaternized ethoxysilane monomer: A secondary amino quaternized ethoxysilane monomer is generated by the addition reaction of the -NH2 functional group of (3-aminopropyl)dimethylethoxysilane with the α,β-alkenyl functional group of acryloyloxyethyltrimethylammonium chloride, with the molar ratio of (3-aminopropyl)dimethylethoxysilane to acryloyloxyethyltrimethylammonium chloride controlled at 1:0.96. The preparation steps are as follows: Under nitrogen protection, 3.2 g of (3-aminopropyl)dimethylethoxysilane... A silane (CAS No. 18306-79-1) and 30 mL of anhydrous N,N-dimethylformamide were added to a three-necked flask and stirred at room temperature until completely dissolved. Then, 30 mL of anhydrous N,N-dimethylformamide solution containing 3.7 g of acryloyloxyethyltrimethylammonium chloride (CAS No. 44992-01-0) was added to the flask. The mixture was heated to 70 °C and stirred for 4 h. After cooling to room temperature, the mixture was rotary evaporated under reduced pressure and dried to obtain a secondary aminoquaternized ethoxysilane monomer with the following chemical structure:

[0042] ;

[0043] (3) Preparation of secondary amino quaternized linear organosilicon compounds: A secondary amino quaternized linear organosilicon compound is generated by condensation reaction of the silyl ethoxy group (-Si-O-CH2CH3) of the diethoxy linear silane monomer with the silyl ethoxy group of the secondary amino quaternized ethoxy silane monomer, and the molar ratio of the diethoxy linear silane monomer to the secondary amino quaternized ethoxy silane monomer is controlled at 1:2.02. The preparation steps are as follows: 2.7 g of diethoxy linear silane monomer, 25 mL of anhydrous N,N- Dimethylformamide and 5 mL of deionized water were added to a three-necked flask and stirred at room temperature for 30 min. Then, 30 mL of a secondary aminoquaternized ethoxysilane monomer solution (prepared from 3.5 g of secondary aminoquaternized ethoxysilane monomer, 25 mL of anhydrous N,N-dimethylformamide, and 5 mL of deionized water) and 2 drops of glacial acetic acid were added sequentially to the flask. The mixture was heated to 60 °C and stirred for 10 h. After cooling to room temperature, the mixture was rotary evaporated under reduced pressure and dried to obtain a secondary aminoquaternized linear organosilicon compound with the following chemical structure:

[0044] ;

[0045] The 1H NMR characterization of secondary amine quaternized linear organosilicon compounds is as follows: 1H NMR (DMSO-d6, 400MHz) δ: 0.02 (s, 12H), 0.05 (s, 12H), 0.07 (s, 12H), 0.12 (s, 12H), 0.70-0.80 (m, 12H), 1.41-1.48 (m, 4H), 2.49-2.53 (t, 4H), 2.63-2.68(m, 4H), 2.91-2.96(m, 4H), 3.36(s, 18H), 3.65-3.69(t, 4H), 4.00-4.06(m, 2H), 4.32-4.35(t, 4H).

[0046] Example 2:

[0047] The preparation of secondary amine quaternized cage-type organosilicon compounds includes the following process:

[0048] (1) Preparation of diethoxy cage-type silane monomers: A diethoxy cage-type silane monomer is generated by the addition reaction of the Si-H functional group of hexamethyldihydroPOSS with the alkenyl functional group of vinyldimethylethoxysilane, with the molar ratio of hexamethyldihydroPOSS to vinyldimethylethoxysilane controlled at 1:2.04. The difference between the preparation steps and those of diethoxy linear silane monomers lies only in the use of 5.1 g of hexamethyldihydroPOSS to replace 2.8 g of 1,1,3,3,5,5,7,7-octamethyltetrasiloxane. Its chemical structural formula is:

[0049] ;

[0050] The preparation method of hexamethyldihydroPOSS is as follows: Acid-catalyzed hydrolysis and condensation reaction of methyltrimethoxysilane and trimethoxysilane is carried out, and the molar ratio of methyltrimethoxysilane to trimethoxysilane is controlled at 3.02:1 to generate hexamethyldihydroPOSS. The preparation steps are as follows: Under nitrogen protection and mechanical stirring, 8.2 g of methyltrimethoxysilane (CAS No. 1185-55-3) and 2.4 g of trimethoxysilane (CAS No. 2487-90-3) are mixed evenly and then added dropwise to a mixed solution composed of 60 mL of anhydrous ethanol, 5 mL of deionized water, and 2 mL of concentrated hydrochloric acid. The mixture is heated to 50 °C and stirred for 4 h, then stirred at room temperature for 40 h. After filtration, washing with ethanol, and drying, hexamethyldihydroPOSS is obtained. Its chemical structural formula is:

[0051] ;

[0052] The 1H NMR spectrum of hexamethyldihydroPOSS is characterized as follows: 1 H NMR (DMSO-d6, 400MHz) δ: 0.17 (s, 18H), 2.76 (s, 2H);

[0053] (2) The secondary amino quaternized ethoxysilane monomer was prepared by the same method as that used in Example 1.

[0054] (3) Preparation of secondary amino quaternized cage-type organosilicon compounds: A condensation reaction is performed between the silylethoxy group (-Si-O-CH2CH3) of the diethoxy cage-type silane monomer and the silylethoxy group of the secondary amino quaternized ethoxysilane monomer, with the molar ratio of the diethoxy cage-type silane monomer to the secondary amino quaternized ethoxysilane monomer controlled at 1:2.02. The secondary amino quaternized cage-type organosilicon compound is generated. The only difference between its preparation steps and those of the secondary amino quaternized linear organosilicon compound is that 3.8 g of the diethoxy cage-type silane monomer is used to replace 2.7 g of the diethoxy linear silane monomer. Its chemical structural formula is:

[0055] ;

[0056] The 1H NMR characterization of the secondary amino quaternized cage-like organosilicon compounds is as follows: 1 H NMR (DMSO-d6, 400MHz) δ: 0.03 (s, 18H), 0.08 (s, 12H), 0.11 (s, 12H), 0.65-0.71 (m, 8H), 0.79-0.82 (t, 4H), 1.38-1.45 (m, 4H), 2.48-2.51 (t , 4H), 2.65-2.70(m, 4H), 2.91-2.96(m, 4H), 3.37(s, 18H), 3.68-3.72(t, 4H), 3.99-4.05(m, 2H), 4.29-4.33(t, 4H).

[0057] Example 3:

[0058] A quaternized organosilicon-modified PVC-I was prepared, with the following formulation: 94 wt% polyvinyl chloride resin and 6 wt% secondary amine quaternized linear organosilicon compound. The preparation method involved a nucleophilic substitution reaction between the secondary amine functional group in the secondary amine quaternized linear organosilicon compound and the chlorine functional group on the PVC molecular chain, thereby achieving graft modification of the PVC resin by the secondary amine quaternized linear organosilicon compound. The preparation steps were as follows: under nitrogen protection, 9.4 g of PVC resin (type...) was... Add 100 mL of anhydrous N,N-dimethylformamide (labeled SG-5) and 100 mL of anhydrous N,N-dimethylformamide to a three-necked flask, heat to 60 °C and stir until completely dissolved. Then, add 10 mL of anhydrous N,N-dimethylformamide solution containing 0.6 g of secondary amine quaternized linear organosilicon compound and 5 mL of triethylamine catalyst to the three-necked flask. Heat to 90 °C and stir for 12 h. Cool to room temperature, pour into a 30 wt% methanol aqueous solution, filter, wash repeatedly with 30 wt% methanol aqueous solution, and dry to obtain quaternized organosilicon modified PVC-I.

[0059] Example 4:

[0060] A quaternized organosilicon-modified PVC-II was prepared. Its formulation consisted of 94 wt% polyvinyl chloride resin and 6 wt% secondary quaternized cage-type organosilicon compound. The preparation method involved a nucleophilic substitution reaction between the secondary amine functional groups in the secondary quaternized cage-type organosilicon compound and the chlorine functional groups on the PVC molecular chain. This resulted in the grafting modification of the PVC resin by the secondary quaternized cage-type organosilicon compound, yielding quaternized organosilicon-modified PVC-II. The only difference between this preparation method and that of quaternized organosilicon-modified PVC-I was the substitution of 0.6 g of the secondary quaternized cage-type organosilicon compound for 0.6 g of the secondary quaternized linear organosilicon compound.

[0061] Example 5:

[0062] A quaternized organosilicon-modified PVC-III was prepared with the following formulation: 94 wt% polyvinyl chloride resin, 3 wt% secondary amino quaternized linear organosilicon compound, and 3 wt% secondary amino quaternized cage-type organosilicon compound. The preparation method involved a nucleophilic substitution reaction between the secondary amine functional groups in the secondary amino quaternized linear organosilicon compound and the secondary amino quaternized cage-type organosilicon compound and the chlorine functional groups on the PVC molecular chain. This resulted in the grafting modification of the PVC resin by the two compounds, yielding quaternized organosilicon-modified PVC-III. The specific preparation steps differed from those of quaternized organosilicon-modified PVC-I only in that 0.3 g of the secondary amino quaternized linear organosilicon compound and 0.3 g of the secondary amino quaternized cage-type organosilicon compound were used to replace 0.6 g of the secondary amino quaternized linear organosilicon compound.

[0063] Example 6:

[0064] The preparation of sulfonated conductive carbon black filler includes the following processes:

[0065] (1) Preparation of hydroxylated conductive carbon black filler: 10g of conductive carbon black powder (particle size of 20-30nm) and 200mL of 20wt% hydrogen peroxide aqueous solution were added to a three-necked flask, and the mixture was sonicated at room temperature for 30min to disperse it evenly. The temperature was raised to 85℃ and stirred for 10h. After cooling to room temperature, the mixture was separated by centrifugation. The mixture was repeatedly washed and centrifuged with deionized water and dried to obtain hydroxylated conductive carbon black filler.

[0066] (2) Preparation of sulfonated conductive carbon black filler: The hydroxyl functional groups on the surface of the hydroxylated conductive carbon black filler undergo a ring-opening reaction with 1,3-propanesulfonic acid lactone to form sulfonic acid groups, and are then neutralized with sodium hydroxide to obtain sulfonated conductive carbon black filler. The preparation steps are as follows: 10g of hydroxylated conductive carbon black filler and 200mL of anhydrous N,N-dimethylformamide are added to a three-necked flask and ultrasonically dispersed at room temperature for 30min. Under nitrogen protection, 5mL of anhydrous N,N-dimethylformamide solution containing 0.5g of 1,3-propanesulfonic acid lactone is added to the three-necked flask. The temperature is raised to 80℃ and stirred for 12h. After cooling to room temperature, 10mL of 15wt% sodium hydroxide aqueous solution is added dropwise and stirred at room temperature for 30min. After centrifugation, the filler is repeatedly washed and centrifuged with deionized water and dried to obtain sulfonated conductive carbon black filler.

[0067] Example 7:

[0068] An antistatic PVC calendered film comprises the following raw materials in parts by weight:

[0069] 40 parts of PVC resin (model SG-5);

[0070] 50 parts of quaternized organosilicon-modified PVC;

[0071] 9 parts sulfonated conductive carbon black filler;

[0072] 1 part heat stabilizer (model WWP-R03);

[0073] Among them, quaternized organosilicon modified PVC is one of quaternized organosilicon modified PVC-Ⅰ, quaternized organosilicon modified PVC-Ⅱ, and quaternized organosilicon modified PVC-Ⅲ.

[0074] Example 8:

[0075] Preparation of antistatic PVC calendered film: In the presence of a heat stabilizer, quaternized organosilicon-modified PVC and sulfonated conductive carbon black filler are first mixed. The sulfonate groups in the sulfonated conductive carbon black filler and the quaternary ammonium salt groups in the quaternized organosilicon-modified PVC undergo electrostatic adsorption, achieving ion-bonded interfacial compatibility between the conductive carbon black filler and the PVC matrix. Then, PVC resin is composited, and the film is calendered to obtain the antistatic PVC calendered film. The preparation steps are as follows: Quaternized organosilicon-modified PVC, sulfonated conductive carbon black filler, and heat stabilizer are added to a high-speed mixer. In the mixing machine, the mixture is mixed for 10 minutes at 100℃ and 1200r / min. After being discharged and cooled to 40℃, it is placed in an internal mixer and mixed at 180℃ for 2 minutes. The formulated amount of PVC resin is added and the mixture is mixed for another 5 minutes. After homogenization in an open mill (170℃), it is transferred to a filter (175℃, 150-mesh double-layer filter screen) for filtration. Finally, it is calendered and formed using a calendering machine with a calendering roller temperature of 180℃ and a speed of 40m / min, and a cooling roller temperature of 30℃ and a speed of 40.2m / min. The film is then slit and wound up to obtain an antistatic PVC calendered film with a thickness of 150μm.

[0076] When the quaternized organosilicon modified PVCs are respectively quaternized organosilicon modified PVC-Ⅰ, Ⅱ, and Ⅲ, antistatic PVC calendered films Ⅰ, Ⅱ, and Ⅲ are prepared sequentially.

[0077] Comparative Example 1:

[0078] The PVC calendered film a is prepared, and its only difference from the antistatic PVC calendered film III is that conductive carbon black powder (particle size of 20-30nm) is used instead of sulfonated conductive carbon black filler.

[0079] Comparative Example 2:

[0080] The PVC calendered film b is prepared in the following ways: it differs from the antistatic PVC calendered film III only in that: conductive carbon black powder (particle size 20-30nm) is used to replace the sulfonated conductive carbon black filler, and PVC resin (model SG-5) is used to replace the quaternized organosilicon modified PVC-III.

[0081] Performance testing:

[0082] I. Antistatic performance test: The volume resistivity of the membrane sample was measured using an impedance analyzer according to GB / T 31838.2-2019 standard, and the test voltage was 300V;

[0083] II. Mechanical property testing:

[0084] (1) Tensile strength test: The longitudinal tensile strength of the film sample was measured using a universal electronic testing machine according to GB / T 1040.3-2006 standard (calendering direction is longitudinal), and the tensile rate was 100 mm / min;

[0085] (2) Impact toughness test: The pendulum impact energy of the membrane sample was measured according to GB / T 8809-2015 standard using a pendulum impact tester. The sample size was 100mm×100mm and the punch type was A.

[0086] The experimental results are shown in Table 1.

[0087] Table 1. Experimental results of the performance of antistatic PVC calendered film

[0088] Product Type Volume resistivity (Ω·cm) Longitudinal tensile strength (MPa) Anti-pendulum impact energy (J) Antistatic PVC Calendered Film I <![CDATA[6.2×10 7 ]]> 34.6 1.13 Antistatic PVC Calendered Film II <![CDATA[5.9×10 7 ]]> 45.2 0.64 Antistatic PVC Calendered Film III <![CDATA[6.0×10 7 ]]> 45.0 1.10 Comparative Example 1 <![CDATA[1.3×10 10 ]]> 42.1 0.98 Comparative Example 2 <![CDATA[1.7×10 10 ]]> 46.4 0.26

[0089] A comprehensive analysis of the above experimental results leads to the following conclusions:

[0090] Conclusion 1: Referring to national industry standards and enterprise user requirements: when 10 6 Ω·cm≤volume resistivity≤10 9 When the value is Ω·cm, the material is considered to have good electrostatic dissipation capability;

[0091] Accordingly, the PVC calendered film product prepared by the present invention has an antistatic effect;

[0092] Conclusion 2: By utilizing the synergistic effect of secondary amine quaternized linear organosilicon compounds and secondary amine quaternized cage-type organosilicon compounds, the present invention produces an antistatic PVC calendered film III that maintains a high tensile strength (45 MPa) comparable to that of the pure rigid modified system while significantly improving its impact toughness (approximately 70% higher than that of the pure rigid film II and approximately 4.2 times higher than that of the unmodified comparative example II), thus achieving a functional balance between antistatic properties and mechanical strength and toughness.

Claims

1. An antistatic PVC calendered film, characterized in that, The ingredients include the following parts by weight: 30-45 parts PVC resin; 45-60 parts of quaternized organosilicon-modified PVC; 8-12 parts sulfonated conductive carbon black filler; 0.5-3 parts heat stabilizer; Among them, the quaternized organosilicon modified PVC is prepared by grafting secondary amine quaternized linear organosilicon compounds and secondary amine quaternized cage organosilicon compounds onto the PVC molecular chain through a nucleophilic substitution reaction of secondary amine-chlorine; the formulation of the quaternized organosilicon modified PVC is: 86-96wt% polyvinyl chloride resin, 2-7wt% secondary amine quaternized linear organosilicon compounds and 2-7wt% secondary amine quaternized cage organosilicon compounds; The sulfonated conductive carbon black filler is prepared by grafting 1,3-propanesulfonate lactone onto the surface of hydroxylated conductive carbon black filler via a sulfonate lactone-hydroxy ring-opening reaction, followed by alkali neutralization treatment; the mass ratio of 1,3-propanesulfonate lactone to hydroxylated conductive carbon black filler in the sulfonated conductive carbon black filler is (0.3-1):10; the particle size of the hydroxylated conductive carbon black filler is 20-30 nm. The chemical structural formula of the secondary amino quaternized linear organosilicon compound is as follows: ； The chemical structural formula of the secondary amino quaternized cage-type organosilicon compound is as follows: 。 2. The method for preparing an antistatic PVC calendered film according to claim 1, characterized in that, Includes the following steps: Step 1: By conducting a nucleophilic substitution reaction between the secondary amine functional groups in the secondary amine quaternized linear organosilicon compound and the secondary amine quaternized cage organosilicon compound and the chlorine functional groups on the PVC molecular chain, the grafting modification treatment of PVC resin by the secondary amine quaternized linear organosilicon compound and the secondary amine quaternized cage organosilicon compound is achieved, resulting in quaternized organosilicon modified PVC. Step 2: The hydroxyl functional groups on the surface of the hydroxylated conductive carbon black filler undergo a ring-opening reaction with 1,3-propanesulfonic acid lactone to form sulfonic acid groups, and then the filler is neutralized with sodium hydroxide to obtain sulfonated conductive carbon black filler. Step 3: In the presence of a heat stabilizer, quaternized organosilicon-modified PVC and sulfonated conductive carbon black filler are first mixed. The sulfonate groups in the sulfonated conductive carbon black filler and the quaternary ammonium salt groups in the quaternized organosilicon-modified PVC undergo electrostatic adsorption, achieving ion-bonded interfacial compatibility between the conductive carbon black filler and the PVC matrix. Then, PVC resin is compounded and calendered to obtain an antistatic PVC calendered film.

3. The method for preparing an antistatic PVC calendered film according to claim 2, characterized in that, The preparation method of the secondary amino quaternized linear organosilicon compound is as follows: An addition reaction is carried out between the Si-H functional group of 1,1,3,3,5,5,7,7-octamethyltetrasiloxane and the alkenyl functional group of vinyldimethylethoxysilane, and the molar ratio of 1,1,3,3,5,5,7,7-octamethyltetrasiloxane to vinyldimethylethoxysilane is controlled to be 1:2.01-2.05, to generate a diethoxy linear silane monomer; The addition reaction between the -NH2 functional group of (3-aminopropyl)dimethylethoxysilane and the α,β-alkenyl functional group of acryloyloxyethyltrimethylammonium chloride, with the molar ratio of (3-aminopropyl)dimethylethoxysilane to acryloyloxyethyltrimethylammonium chloride controlled at 1:0.95-0.99, yields a secondary aminoquaternized ethoxysilane monomer. A secondary amino-quaternized linear organosilicon compound is generated by a condensation reaction between the silyl ethoxy group of a diethoxy linear silane monomer and the silyl ethoxy group of a secondary amino-quaternized ethoxy silane monomer, with the molar ratio of the diethoxy linear silane monomer to the secondary amino-quaternized ethoxy silane monomer controlled at 1:2.01-2.

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4. The method for preparing an antistatic PVC calendered film according to claim 3, characterized in that, The preparation method of the secondary amino quaternized cage-type organosilicon compound is as follows: The addition reaction between the Si-H functional group of hexamethyldihydroPOSS and the alkenyl functional group of vinyldimethylethoxysilane is carried out, and the molar ratio of hexamethyldihydroPOSS to vinyldimethylethoxysilane is controlled to be 1:2.01-2.05, to generate diethoxycage silane monomer. A secondary amino-quaternized cage-type organosilicon compound is generated by a condensation reaction between the silyl ethoxy group of the diethoxy cage-type silane monomer and the silyl ethoxy group of the secondary amino-quaternized ethoxysilane monomer, and by controlling the molar ratio of the diethoxy cage-type silane monomer to the secondary amino-quaternized ethoxysilane monomer to be 1:2.01-2.

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5. The method for preparing an antistatic PVC calendered film according to claim 4, characterized in that, The preparation method of the hexamethyldihydroPOSS is as follows: the hexamethyldihydroPOSS is generated by acid-catalyzing the hydrolysis and condensation reaction of methyltrimethoxysilane and trimethoxysilane, and controlling the molar ratio of methyltrimethoxysilane and trimethoxysilane to be 3.01-3.05:1.

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