Production method of cross-linking type air conditioner heat preservation drain pipe

Abstract

The invention provides a preparation method of a cross-linking type air conditioner heat preservation drain pipe. According to the method, polybutadiene modified polyethylene resin is adopted as an assistant cross-linking agent, uniform dispersion of the polybutadiene modified polyethylene resin in the product is promoted, the polybutadiene modified polyethylene resin and polyolefin molecular chains are well mixed and wound, the crosslinking degree of the product is improved by means of rich double-bond structures in polybutadiene, and the cross-linking type air conditioner heat preservation drain pipe is prepared. The method provided by the invention has the following advantages: (1) the mechanical property of the product is good, the breaking strength is greater than or equal to 270 N, the elongation at break is greater than or equal to 150%, and the indentation hardness is greater than or equal to 420 N; (2) the crosslinking degree is high, and the gel content is greater than or equal to 30%; (3) the raw materials are rich in source and low in price; and (4) the prepared drain pipe has a wide market prospect in the aspect of air conditioner drain pipes.

Description

Technical Field

[0001] The invention relates to a method for preparing a cross-linked air-conditioning thermal insulation drainage pipe, belonging to the technical field of polymer materials. Background Art

[0002] Polyolefin plastic hoses are widely used as drainage pipes for household appliances such as air conditioners and washing machines. They have many advantages such as light weight and adjustable appearance.

[0003] Due to its high crystallinity, the molecular chains of polyolefin resins will gradually rearrange themselves to form a stable crystalline structure over time, resulting in severe deformation creep. At the same time, the flexible molecular chains of polyolefins reduce their mechanical strength, especially at the interfaces, which are prone to deformation and loosening, causing water leakage. Therefore, improving the creep resistance and mechanical properties of air-conditioning drain pipes is very important to improving the performance of the drain pipes.

[0004] Therefore, new solutions need to be proposed to solve this problem. Summary of the invention

[0005] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a method for preparing a cross-linked air-conditioning insulation drainage pipe, and polybutadiene-modified polyethylene resin is used as a co-cross-linking agent to solve the problems existing in the background technology.

[0006] The present invention solves the technical problem through the following technical scheme: based on the traditional formula, polybutadiene-modified polyethylene resin is used as a cross-linking agent to promote its more uniform dispersion in the product, better mixing and entanglement with the polyolefin molecular chain, and the rich double bond structure in polybutadiene is utilized to improve the cross-linking degree of the product.

[0007] The above technical objectives of the present invention are achieved through the following technical solutions: a production method of a cross-linked air-conditioning thermal insulation drainage pipe, wherein the pipe is made of the following components in parts by weight: 60 to 95 parts by weight of polyethylene resin, 5 to 30 parts by weight of polybutadiene-modified polyethylene resin, 1 to 3 parts by weight of a crosslinking agent, 0.5 to 2 parts by weight of anti-aging agent; The cross-linked air-conditioning thermal insulation drainage pipe is prepared by mixing 60 to 95 parts by weight of polyethylene resin, 5 to 30 parts by weight of polybutadiene-modified polyethylene resin, 1 to 3 parts by weight of a cross-linking agent, and 0.5 to 2 parts by weight of an anti-aging agent, and then adding the mixture into a screw extruder for mixing and extrusion, thereby preparing the cross-linked air-conditioning thermal insulation drainage pipe.

[0008] Furthermore, the polybutadiene-modified polyethylene resin is prepared by mixing 100 parts by weight of polyethylene, 10 to 30 parts by weight of liquid polybutadiene with a molecular weight of 3,000 to 10,000, and 1 part by weight of azobisisobutyronitrile in a 130° C. internal mixer for 0.5 to 2 hours, followed by granulation and extrusion to obtain the polybutadiene-modified polyethylene resin.

[0009] Furthermore, the anti-aging agent is selected from one or more of the following groups: 2-hydroxybenzophenone, 2-(2′-hydroxy-5′-methylphenyl)benzotriazole, N,N′-diphenyl-p-phenylenediamine, and 2,2′-diaminodiphenyl sulfide.

[0010] Furthermore, the cross-linking agent is one or a combination of more than one of benzoyl peroxide, diisopropyl peroxide, di-(tert-butylperoxyisopropyl)benzene, methyl ethyl ketone peroxide, and tert-butyl peroxypivalate.

[0011] Furthermore, a method for preparing a cross-linked air-conditioning thermal insulation drainage pipe is provided, wherein a poly-bio-oil polyol-modified polyethylene resin is introduced as an active component into a basic formula of polyethylene resin and an aging agent to prepare a cross-linked air-conditioning thermal insulation drainage pipe, and the specific operation steps are as follows: Step 1, preparation of polybutadiene modified polyethylene resin; Step 2, production of cross-linked air-conditioning thermal insulation drainage pipe, take 60-95 parts by weight of polyethylene, 5-30 parts by weight of polybutadiene modified polyethylene resin, 1-5 parts by weight of cross-linking agent and 1 part by weight of anti-aging agent, mix them evenly, add them into a single screw extruder for extrusion, control the extrusion temperature at 110-160°C, the screw speed at 60-120rpm, and the die head temperature at 140-180°C to obtain a cross-linked air-conditioning thermal insulation drainage pipe.

[0012] In summary, the present invention has the following beneficial effects: (1) The product has good mechanical properties, breaking strength: ≥270 N, breaking elongation: ≥150%, indentation hardness: ≥430N; (2) High degree of cross-linking, gel content: ≥30%; (3) The raw materials are abundant and inexpensive; (4) The preparation of drainage pipes has broad market prospects in air conditioning drainage pipes. DETAILED DESCRIPTION

[0013] The present invention is described in detail below in conjunction with embodiments.

[0014] It should be noted that: (1) The present invention adopts the method for determining the tensile properties of plastic parts in GB / T 1040.1 to test the mechanical properties of the material.

[0015] (2) The present invention adopts GB / T 10807 Determination of hardness of flexible foam polymeric materials (indentation method) to determine the material hardness (pressing into 60% of the diameter of the sample).

[0016] (3) The present invention adopts the standard of GB / T 18474-2001 to test the crosslinking degree and the gel content of the test sample.

[0017] (4) The present invention adopts the following method to test the air tightness of the product: seal the water inlet and outlet, and apply a certain gas pressure (0.05 MPa is applied to the corrugated insulated drainage pipe with a length greater than or equal to 0.5 m, and 0.025 MPa is applied to the corrugated insulated drainage pipe with a length less than 0.5 m), and completely immerse the pipe body in water and visually inspect it.

[0018] Step 1, preparation of polybutadiene modified polyethylene resin: 100 parts by weight of polyethylene, 15 parts by weight of liquid polybutadiene with a molecular weight of 5000 and 1 part by weight of azobisisobutyronitrile were subjected to internal kneading reaction in an internal mixer at 130° C. for 1.0 hour, and then pelletized and extruded to obtain a polybutadiene-modified polyethylene resin.

[0019] Step 2: Production of cross-linked air conditioning insulation drainage pipe: 85 parts by weight of polyethylene, 15 parts by weight of polybutadiene modified polyethylene resin, 2 parts by weight of diisopropylbenzene peroxide and 1 part by weight of 2,2′-diaminodiphenyl sulfide were mixed evenly, and then added to a single screw extruder for extrusion, and the extrusion temperature was controlled at 110-160°C, the screw speed was 85 rpm, and the die head temperature was 130°C to obtain a cross-linked air conditioning insulation drainage pipe. The breaking strength was 305N, the breaking elongation was 156%, the indentation hardness was 425N, the sealing durability was watertight, and the gel content was 35%.

[0020] The same as Example 1 except for the following differences, different polybutadiene was selected.

[0021] Table 1 Example 2 3 4 5 Polybutadiene Polybutadiene particles Liquid Polybutadiene (4000) Liquid Polybutadiene (7000) Liquid polybutadiene (10000) Breaking strength / N 274 326 327 328 Elongation at break / % 223 132 157 168 Indentation hardness / N 355 453 457 451 Seal durability Slight water leakage Watertight Watertight Watertight Gel content / % 25% 50% 45% 40% When polybutadiene particles were selected, the performance was poor (Example 2).

[0022] Except for the following differences, the rest is the same as Example 1, and a different cross-linking agent is selected.

[0023] Table 2 Example 6 7 8 Crosslinking agent AIBN Di-(tert-butylperoxyisopropyl)benzene Methyl Ethyl Ketone Peroxide Breaking strength / N 297 311 320 Elongation at break / % 124 163 158 Indentation hardness / N 395 455 457 Seal durability Slight water leakage Watertight Watertight Gel content / % 30% 43% 45% When AIBN with a lower decomposition temperature is selected, the product performance is poorer.

[0024] Except for the following differences, the rest is the same as Example 1, and different amounts of polybutadiene-modified polyethylene resin are selected.

[0025] Table 3 Example 9 10 11 12 Polybutadiene modified polyethylene resin dosage / mass parts 0 10 25 30 Breaking strength / N 221 313 320 322 Elongation at break / % 254 143 158 148 Indentation hardness / N 315 451 456 459 Seal durability water leakage Watertight Watertight Watertight Gel content / % 21% 40% 45% 47% When the polybutadiene-modified polyethylene resin is not used, the cold resistance of the product is poor (Example 9).

[0026] The above is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A method for producing a cross-linked air-conditioning thermal insulation drainage pipe, characterized in that: The pipe is made of the following components in parts by weight: 60 to 95 parts by weight of polyethylene resin, 5 to 30 parts by weight of polybutadiene-modified polyethylene resin, 1 to 3 parts by weight of a crosslinking agent, 0.5 to 2 parts by weight of anti-aging agent; The cross-linked air-conditioning thermal insulation drainage pipe is prepared by mixing 60 to 95 parts by weight of polyethylene resin, 5 to 30 parts by weight of polybutadiene-modified polyethylene resin, 1 to 3 parts by weight of a cross-linking agent, and 0.5 to 2 parts by weight of an anti-aging agent, and then adding the mixture into a screw extruder for mixing and extrusion, thereby preparing the cross-linked air-conditioning thermal insulation drainage pipe.

2. The method for producing a cross-linked air-conditioning thermal insulation drainage pipe according to claim 1, characterized in that: The polybutadiene modified polyethylene resin is prepared by mixing 100 parts by weight of polyethylene, 10 to 30 parts by weight of liquid polybutadiene with a molecular weight of 3,000 to 10,000, and 1 part by weight of azobisisobutyronitrile in a 130° C. internal mixer for 0.5 to 2 hours, followed by granulation and extrusion to obtain the polybutadiene modified polyethylene resin.

3. The method for producing a cross-linked air-conditioning thermal insulation drainage pipe according to claim 1, characterized in that: The anti-aging agent is selected from one or more of the following groups: 2-hydroxybenzophenone, 2-(2′-hydroxy-5′-methylphenyl)benzotriazole, N,N′-diphenyl-p-phenylenediamine, and 2,2′-diaminodiphenyl sulfide.

4. The method for producing a cross-linked air-conditioning thermal insulation drainage pipe according to claim 1, characterized in that: The crosslinking agent is one or a combination of more than one of benzoyl peroxide, diisopropyl peroxide, di-(tert-butylperoxyisopropyl)benzene, methyl ethyl ketone peroxide, and tert-butyl peroxypivalate.

5. The method for producing a cross-linked air-conditioning thermal insulation drainage pipe according to claim 2, characterized in that: A method for preparing a cross-linked air-conditioning thermal insulation drainage pipe is provided. Poly(bio-oil) polyol-modified polyethylene resin is introduced as an active component into a basic formula of polyethylene resin and an aging agent to prepare the cross-linked air-conditioning thermal insulation drainage pipe. The specific operation steps are as follows: Step 1, preparation of polybutadiene modified polyethylene resin; Step 2, production of cross-linked air-conditioning thermal insulation drainage pipe, take 60-95 parts by weight of polyethylene, 5-30 parts by weight of polybutadiene modified polyethylene resin, 1-5 parts by weight of cross-linking agent and 1 part by weight of anti-aging agent, mix them evenly, add them into a single screw extruder for extrusion, control the extrusion temperature at 110-160°C, the screw speed at 60-120rpm, and the die head temperature at 140-180°C to obtain a cross-linked air-conditioning thermal insulation drainage pipe.