An antistatic agent and its preparation method and application

Abstract

The present invention provides an antistatic agent and a preparation method and application thereof, and relates to the technical field of antistatic agents. An antistatic agent comprises polyolefin and polar long-chain branched polymer compound. The polyolefin is selected from one or more of ethylene propylene diene monomer copolymer, diethylene-norbornene copolymer and dipropylene-norbornene copolymer. The polar long-chain branched polymer compound is selected from one or more of polyethylene oxide and acrylic acid-acrylate copolymer. The present invention prepares a long-chain polar olefin polymer as a permanent antistatic agent for application in polyolefin film by a two-step process of acidification-grafting, and the reaction conditions are mild and the antistatic effect is good.

Description

Technical Field

[0001] The present invention relates to the technical field of antistatic agents, and in particular to an antistatic agent and a preparation method and application thereof. Background Art

[0002] During the preparation and use of plastic products, static electricity is very likely to accumulate, leading to problems such as damage to production equipment, unstable production process and personal injury. For transparent products such as plastic films, it is difficult to solve this problem by embedding carbon black, copper powder and other solutions, which results in the use of precipitating quaternary ammonium salts, phosphates and other products as antistatic agents for film products. Therefore, it is urgent to develop a long-chain polar olefin polymer antistatic agent, which is of great significance for the widespread application of polyolefin films. Summary of the invention

[0003] Based on the technical problems existing in the background technology, the present invention proposes an antistatic agent and a preparation method and application thereof.

[0004] The invention provides an antistatic agent comprising polyolefin and a polar long-chain branched polymer compound.

[0005] Preferably, the polyolefin is selected from one or more of ethylene propylene diene monomer copolymer, binary ethylene-norbornene copolymer and binary propylene-norbornene copolymer.

[0006] More preferably, the molecular weight of the EPDM copolymer is 2000-200000, and the third member of the EPDM copolymer is norbornene.

[0007] More preferably, the content of norbornene is greater than 1%.

[0008] More preferably, the content of norbornene is 3-10%.

[0009] Preferably, the polar long-chain branched polymer compound is selected from one or more of polyethylene oxide and acrylic acid-acrylate copolymer.

[0010] More preferably, the molecular weight of the polyethylene oxide is 100-1000.

[0011] Preferably, the antistatic agent comprises the following raw materials in parts by weight: 90-110 parts of polyolefin and 3-50 parts of polar long-chain branched polymer compound.

[0012] More preferably, the mass ratio of polyethylene oxide to acrylic acid-acrylate copolymer in the polar long-chain branched polymer compound is (30-50):(50-70).

[0013] The present invention also provides a method for preparing an antistatic agent, comprising the following steps: introducing carboxyl groups into polyolefins through free radical addition reaction, and then combining the carboxyl groups with the branched groups of polar long-chain branched polymer compounds through polycondensation reaction to obtain the antistatic agent.

[0014] Preferably, the free radical addition reaction comprises: introducing carboxyl groups into the polyolefin main chain through a free radical addition reaction of a carboxyl-containing compound.

[0015] More preferably, the carboxyl-containing compound is selected from one or more of maleic anhydride, acrylic acid, and methacrylic acid.

[0016] More preferably, the mass ratio of the carboxyl-containing compound to the polyolefin is (2-10):100.

[0017] More preferably, the initiator in the free radical addition reaction is a peroxide initiator.

[0018] More preferably, the added amount of the initiator is 0.1%-0.3% of the mass of the polyolefin.

[0019] More preferably, the temperature of the free radical addition reaction is 120-160°C.

[0020] Preferably, the polycondensation reaction comprises: the polar long-chain branched polymer compound undergoes condensation with the carboxyl group introduced in the first step via a hydroxyl group, or undergoes an ester exchange reaction with the carboxyl group introduced in the first step to introduce polar long-chain macromolecules to form branches.

[0021] More preferably, the temperature of the polycondensation reaction is 140-180°C.

[0022] Application of the antistatic agent or the antistatic agent prepared by the preparation method in polyolefin film.

[0023] The beneficial effects of the present invention are:

[0024] The invention adopts an acidification-grafting two-step process to prepare a long-chain polar olefin polymer as a permanent antistatic agent for application in a polyolefin film, has mild reaction conditions, high grafting efficiency and good antistatic effect.

[0025] The polyolefin material of the present invention has an unsaturated structure, carboxyl groups are added to norbornene of the polyolefin by a free radical addition method, and polar branches are introduced into the polyolefin chain by a condensation reaction, thereby preparing a long-chain polar olefin polymer with a permanent antistatic effect.

[0026] The present invention introduces a carboxyl group through a free radical addition reaction, has high reactivity and stable active sites. Polar chains are introduced on polyolefins, the polar chains are long, the polar effect is stable, and the static electricity conductivity is strong. By grafting different polar long chain branches, it can not only have an antistatic effect, but also have a permanent anti-fog effect. The carboxyl and polar long chain branch groups have strong reactivity, stable grafting rate, and good site selectivity. The long-chain polar olefin polymer antistatic agent not only has a good antistatic effect on the surface of polyolefins, but also has a stable antistatic effect and does not have precipitation problems. DETAILED DESCRIPTION

[0027] The technical solution of the present invention is described in detail through specific embodiments.

[0028] Unless otherwise specified, the materials, reagents, etc. used in the following examples and comparative examples can be obtained from commercial sources.

[0029] Commercially available migratory antistatic agent masterbatch: Manufacturer: Shantou Best Technology Co., Ltd., brand: AS2335PPTR.

[0030] Example 1

[0031] An antistatic agent comprises 100 parts of polyolefin and 5 parts of polar long-chain branched polymer compound;

[0032] The polyolefin is ethylene propylene diene monomer rubber with norbornene as the third element, the molecular weight is 100,000, the ethylene propylene ratio is 80:20, and the norbornene content is 5%. The polar long-chain branched polymer compound includes polyethylene oxide and acrylic acid-acrylate copolymer, the molecular weight of polyethylene oxide is 500, and the mass ratio of polyethylene oxide and acrylic acid-acrylate copolymer is 30:70.

[0033] A method for preparing an antistatic agent comprises the following steps: introducing a carboxyl group into a polyolefin through a free radical addition reaction, and then combining the carboxyl group with a polar long-chain branched polymer compound through a polycondensation reaction to obtain an antistatic agent. The free radical addition reaction comprises: introducing a carboxyl group into a polyolefin main chain through a free radical addition reaction using a HBr / peroxide system (mass ratio of 1:1.5) at 140°C to obtain a compound A; and the polycondensation reaction comprises: preparing the compound A and the polar long-chain branched polymer compound through a polycondensation reaction at 170°C.

[0034] Application: Take 15 parts of the above antistatic agent and mix it with 100 parts of polypropylene to prepare a polypropylene film. Test its surface resistivity to be 10 12.1 Ω / m 2 .

[0035] Example 2

[0036] An antistatic agent comprises 100 parts of polyolefin and 20 parts of polar long-chain branched polymer compound;

[0037] The polyolefin is ethylene propylene diene monomer rubber with norbornene as the third member, the molecular weight is 100,000, the ethylene propylene ratio is 50:50, and the norbornene content is 7%. The polar long-chain branched polymer compound is polyethylene oxide and acrylic acid-acrylate copolymer, the molecular weight of polyethylene oxide is 600, and the mass ratio of polyethylene oxide and acrylic acid-acrylate copolymer is 40:60.

[0038] A method for preparing an antistatic agent comprises the following steps: introducing a carboxyl group into a polyolefin through a free radical addition reaction, and then combining the carboxyl group with a polar long-chain branched polymer compound through a polycondensation reaction to obtain an antistatic agent. The free radical addition reaction comprises: introducing a carboxyl group into a polyolefin main chain through a free radical addition reaction using a HBr / peroxide system (mass ratio of 1:1.5) at 160°C to obtain a compound A; and the polycondensation reaction comprises: preparing the compound A and the polar long-chain branched polymer compound through a polycondensation reaction at 150°C.

[0039] Application: Take 4.5 parts of the above antistatic agent and mix it with 100 parts of polypropylene to prepare a polypropylene film. The surface resistivity is 10 10.5 Ω / m 2 .

[0040] Example 3

[0041] An antistatic agent comprises 100 parts of polyolefin and 50 parts of polar long-chain branched polymer compound;

[0042] The polyolefin is ethylene propylene diene monomer rubber with norbornene as the third member, the molecular weight is 100,000, the ethylene propylene ratio is 70:30, and the norbornene content is 5%. The polar long-chain branched polymer compound is polyethylene oxide and acrylic acid-acrylate copolymer, the molecular weight of polyethylene oxide is 600, and the mass ratio of polyethylene oxide and acrylic acid-acrylate copolymer is 50:50.

[0043] A method for preparing an antistatic agent comprises the following steps: introducing a carboxyl group into a polyolefin through a free radical addition reaction, and then combining the carboxyl group with a polar long-chain branched polymer compound through a polycondensation reaction to obtain an antistatic agent. The free radical addition reaction comprises: introducing a carboxyl group into a polyolefin main chain through a free radical addition reaction using a HBr / peroxide system (mass ratio of 1:1.5) at 140°C to obtain a compound A; and the polycondensation reaction comprises: preparing the compound A and the polar long-chain branched polymer compound through a polycondensation reaction at 170°C.

[0044] Application: Take 3 parts of the above antistatic agent and mix them evenly with 100 parts of polypropylene to prepare a polypropylene film. Test its surface resistivity to be 10 9.3 Ω / m 2 .

[0045] Example 4

[0046] An antistatic agent comprises 100 parts of polyolefin and 5 parts of polar long-chain branched polymer compound;

[0047] The polyolefin is ethylene propylene diene monomer rubber with norbornene as the third member, the molecular weight is 5000-200,000, the ethylene propylene ratio is 80:20, and the norbornene content is 5%. The polar long-chain branched polymer compound is polyethylene oxide and acrylic acid-acrylate copolymer, the molecular weight of polyethylene oxide is 500, and the mass ratio of polyethylene oxide and acrylic acid-acrylate copolymer is 30:70.

[0048] A method for preparing an antistatic agent comprises the following steps: introducing a carboxyl group into a polyolefin through a free radical addition reaction, and then combining the carboxyl group with a polar long-chain branched polymer compound through a polycondensation reaction to obtain an antistatic agent. The free radical addition reaction comprises: introducing a carboxyl group into a polyolefin main chain through a free radical addition reaction using a HBr / peroxide system (mass ratio of 1:1.5) at 140°C to obtain a compound A; and the polycondensation reaction comprises: preparing the compound A and the polar long-chain branched polymer compound through a polycondensation reaction at 180°C.

[0049] Application: Take 15 parts of the above antistatic agent and mix it with 100 parts of polyethylene to prepare a polyethylene film. The surface resistivity is 10 12.1 Ω / m 2 .

[0050] Comparative Example 1

[0051] Polypropylene only.

[0052] The surface resistivity is 10 13 Ω / m 2 , 10 13 Ω / m 2 It is the minimum current limit of the equipment test, indicating that the film surface has no electrostatic conductivity effect, and its actual surface resistance will be much greater than 10 13 Ω / m 2 .

[0053] Comparative Example 2

[0054] Polyethylene only.

[0055] The surface resistivity is 10 13 Ω / m2 , 10 13 Ω / m 2 It is the minimum current limit of the equipment test, indicating that the film surface has no electrostatic conductivity effect, and its actual surface resistance will be much greater than 10 13 Ω / m 2 .

[0056] Comparative Example 3

[0057] Application: Take 2 parts of commercially available migratory antistatic agent masterbatch and mix them evenly with 100 parts of polypropylene to prepare a polypropylene film. The surface resistivity is 10 11.4 Ω / m 2 , the surface resistivity begins to decline after half a year.

[0058] In summary, the antistatic agent provided by the present invention is applied to polyolefin films, which can significantly reduce the surface resistivity of polyolefin films and improve their antistatic effect. The antistatic agent of the present invention has a stable antistatic effect, and the surface resistivity of the film material does not show a significant decline within one year when applied thereto.

[0059] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. An antistatic agent, characterized in that Including polyolefins and polar long-chain branched polymer compounds.

2. The antistatic agent according to claim 1, characterized in that The polyolefin is selected from one or more of ethylene propylene diene monomer copolymer, binary ethylene-norbornene copolymer and binary propylene-norbornene copolymer.

3. The antistatic agent according to claim 2, characterized in that The molecular weight of the EPDM copolymer is 2000-200000, and the third member of the EPDM copolymer is norbornene.

4. The antistatic agent according to claim 3, characterized in that The content of norbornene is greater than 1%.

5. The antistatic agent according to claim 1, characterized in that The polar long-chain branched polymer compound is selected from one or more of polyethylene oxide and acrylic acid-acrylate copolymer.

6. The antistatic agent according to claim 1, characterized in that The invention comprises the following raw materials in parts by weight: 90-110 parts by weight of polyolefin and 3-50 parts by weight of polar long-chain branched polymer compound.

7. A method for preparing the antistatic agent according to any one of claims 1 to 6, characterized in that: The method comprises the following steps: introducing carboxyl groups into polyolefin through free radical addition reaction, and then combining the carboxyl groups with the branched groups of polar long-chain branched polymer compounds through polycondensation reaction to obtain an antistatic agent.

8. The preparation method according to claim 7, characterized in that: The free radical addition reaction comprises: introducing a carboxyl group into the main chain of the polyolefin by a free radical addition reaction of a carboxyl-containing compound; the carboxyl-containing compound is selected from one or more of maleic anhydride, acrylic acid and methacrylic acid.

9. Use of the antistatic agent according to any one of claims 1 to 6 or the antistatic agent prepared by the preparation method according to any one of claims 7 to 8 in polyolefin films.