阅读说明：本技术 一种高密度聚乙烯管材混配料及其制备方法 (High-density polyethylene pipe mixed material and preparation method thereof ) 是由 李波 梁胜轲 杜中杰 金华 王武聪 孙佩鑫 侯斌 于 2019-11-05 设计创作，主要内容包括：本发明公开了一种高密度聚乙烯管材混配料及其制备方法,属于塑料管材生产技术领域,高密度聚乙烯管材混配料包括高密度聚乙烯、炭黑母料和相容剂,通过双螺杆挤出加工造粒而成；其中炭黑母料的含量为高密度聚乙烯质量的5％,相容剂的含量为高密度聚乙烯质量的0.1～3.0％。本发明管材混配料的制备方法简单,制备得到的管材混配料中炭黑分散均匀,制备得到的管材还具有质量稳定、使用寿命长的优点。(The invention discloses a high-density polyethylene pipe mixed material and a preparation method thereof, belonging to the technical field of plastic pipe production, wherein the high-density polyethylene pipe mixed material comprises high-density polyethylene, carbon black master batch and compatilizer, and is prepared by extruding, processing and granulating through double screws; wherein the content of the carbon black master batch is 5% of the mass of the high-density polyethylene, and the content of the compatilizer is 0.1-3.0% of the mass of the high-density polyethylene. The preparation method of the pipe mixed material is simple, the carbon black in the prepared pipe mixed material is uniformly dispersed, and the prepared pipe also has the advantages of stable quality and long service life.)

1. The high-density polyethylene pipe mixing material is characterized in that: comprises high-density polyethylene, carbon black master batch and compatilizer, and is formed by extruding, processing and granulating through double screws; wherein the content of the carbon black master batch is 5% of the mass of the high-density polyethylene, and the content of the compatilizer is 0.1-3.0% of the mass of the high-density polyethylene.

2. The high density polyethylene pipe compound according to claim 1, wherein: the high-density polyethylene has a melt index of 0.01-2.5 g/10min at 190 ℃ and under a pressure of 2.16 kg.

3. The high density polyethylene pipe compound according to claim 2, wherein: the high-density polyethylene has a melt index of 0.05-2.00 g/10min at a temperature of 190 ℃ and a pressure of 2.16 kg.

4. The high density polyethylene pipe compound according to claim 1, wherein: the carrier of the carbon black master batch is one or a mixture of two of linear low-density polyethylene and high-density polyethylene, and the content of carbon black in the carbon black master batch is 30-60%.

5. The high density polyethylene pipe compound according to claim 4, wherein: the carbon black content in the carbon black master batch is 40-50%.

6. The high density polyethylene pipe compound according to claim 1, wherein: the compatilizer is modified polytetrafluoroethylene micro powder, the modified polytetrafluoroethylene micro powder is prepared from polytetrafluoroethylene micro powder, a modified monomer and peroxide, and the mass ratio of the polytetrafluoroethylene micro powder to the modified monomer to the peroxide is 100: 0.1-1.0: 0.1-0.5; the average particle size D50 of the compatilizer is 1-20 microns, and the number average molecular weight is 5000-30000; the compatilizer is of a porous structure, and the porosity is 25-75%.

7. The high density polyethylene pipe compound according to claim 6, wherein: the modified monomer is any one of maleic anhydride, acrylic acid, methacrylic acid, fumaric acid and glycidyl methacrylate; the peroxide is any one of dicumyl peroxide, diacetyl peroxide, dibenzoyl peroxide, diisobutylene peroxide, tert-butyl dicumyl peroxide and tert-butyl acetate peroxide.

8. A preparation method of a high-density polyethylene pipe material mixing material is characterized by comprising the following steps:

A. preparing a compatilizer: weighing polytetrafluoroethylene micro powder, a modified monomer and peroxide according to a preset proportion, adding the polytetrafluoroethylene micro powder, the modified monomer and the peroxide into a high-pressure reaction kettle, sealing, uniformly stirring, heating to 200 ℃, introducing supercritical carbon dioxide, controlling the pressure to be 20MPa, keeping for 10min, and relieving pressure;

B. preparing a mixed material: weighing high-density polyethylene, carbon black master batch and compatilizer in a preset proportion, uniformly mixing, and then extruding and processing by a double screw to granulate.

9. The method for preparing the high density polyethylene pipe compound according to claim 8, wherein the method comprises the following steps: the temperature rising rate in the step A is 20 ℃/min, and supercritical carbon dioxide is introduced until the pressure of the reaction kettle is 20 MPa; and the temperature of the twin-screw extrusion processing in the step B is 200-210 ℃, and the rotating speed of the screw is 100-400 rpm.

Technical Field

The invention relates to a polyethylene pipe mixed material, in particular to a high-density polyethylene pipe mixed material and a preparation method thereof, belonging to the technical field of plastic pipe production.

Background

The plastic pipe is a chemical building material formed by high-tech compounding, and the chemical building material is a fourth novel building material which is newly developed in the modern time after steel, wood and cement. The chemical building materials are developed rapidly and greatly in China, and particularly, the novel environment-friendly plastic pipes are widely used, so that a revolution of replacing the traditional building materials is raised. The plastic pipe has the advantages of small water flow loss, energy conservation, material saving, ecological protection, convenient completion and the like, is widely applied to the fields of building water supply and drainage, town water supply and drainage, gas pipes and the like, and becomes the main force of a new century urban pipe network.

The plastic pipes mainly comprise a UPVC drain pipe, a UPVC water supply pipe, an aluminum-plastic composite pipe, a Polyethylene (PE) water supply pipe and a polypropylene PPR hot water pipe. High Density Polyethylene (HDPE), also known as low pressure Polyethylene, is a translucent material with High crystallinity and a non-polar surface. PE pipes are further classified into five grades, PE32, PE40, PE63, PE80, PE100, according to their long term hydrostatic strength (MRS). Currently, the largest number of PE pipes used internationally is PE 80. With the improvement of the requirement on the pipe, the pipe resin with the MRS value of 100MPa (PE 100 grade) has bimodal molecular weight distribution and hexene copolymer, has stronger creep resistance, improves the long-term hydrostatic strength, improves the slow crack growth resistance and the fast crack propagation resistance, and provides favorable conditions for increasing the pipe diameter, improving the transportation pressure of a pipe network and expanding the application range.

The production mode of the traditional processing enterprises in manufacturing PE100 plastic pipes is as follows: and adding black master batch into the natural-color polyethylene. The dispersion performance of carbon black in a polyethylene resin matrix is closely related to the quality index of the pipe, and with the revision and implementation of the national standard GBT13663-2000, how to produce the polyethylene pipe with uniformly dispersed carbon black becomes the key for the transformation of enterprise products. The existing black polyethylene pipe is prepared by adding carbon black master batch in the extrusion granulation process of polyethylene, but the compatibility of inorganic carbon black particles and an organic polyethylene resin matrix is poor, and carbon black particles have strong aggregation tendency. Therefore, the carbon black is difficult to uniformly disperse in the polyethylene matrix, so that the pipe quality is unstable and the service life is short.

In order to uniformly distribute carbon black in polyethylene resin, some conventional methods add a compatilizer in the preparation process of a pipe to promote uniform distribution of the carbon black, but the types of the conventional compatilizers are very different, and the component types and the preparation method of the compatilizer have crucial influence on the function of the compatilizer. Whether the compatibilizer can promote the uniform distribution of the carbon black in the polyethylene resin or not is an important judgment index. Porosity is the percentage of the volume of pores in the bulk material to the total volume of the material in its natural state, and the characteristic state of the pores, in addition to the amount of the pores inside the material, is one of the important factors affecting the properties of the material. The pore characteristics of the material are characterized by whether the pores are closed inside the material or open to the outside at the surface of the material. The former is a closed pore and the latter is an open pore. Some pores are separated into independent pores inside the material, and other pores are communicated with each other inside the material. In addition, the size of the pores, the uniformity of the distribution of the pores in the material, and the like are all characteristic expressions of the pores in the material, and are closely related to the effect of the compatilizer on improving the dispersibility.

Disclosure of Invention

The technical problem to be solved by the invention is to provide a high-density polyethylene pipe mixing material and a preparation method thereof, which can improve the uniform dispersion of carbon black and improve the stability of pipe quality.

In order to solve the technical problems, the technical scheme adopted by the invention is as follows:

a high-density polyethylene pipe mixing material comprises high-density polyethylene, carbon black master batch and compatilizer, and is prepared by extruding, processing and granulating through double screws; wherein the content of the carbon black master batch is 5% of the mass of the high-density polyethylene, and the content of the compatilizer is 0.1-3.0% of the mass of the high-density polyethylene.

The technical scheme of the invention is further improved as follows: the high-density polyethylene has a melt index of 0.01-2.50 g/10min at a temperature of 190 ℃ and a pressure of 2.16 kg.

The technical scheme of the invention is further improved as follows: the high-density polyethylene has a melt index of 0.05-2.00 g/10min at a temperature of 190 ℃ and a pressure of 2.16 kg.

The technical scheme of the invention is further improved as follows: the carrier of the carbon black master batch is one or a mixture of two of linear low-density polyethylene and high-density polyethylene, and the content of carbon black in the carbon black master batch is 30-60%.

The technical scheme of the invention is further improved as follows: the carbon black content in the carbon black master batch is 40-50%.

The technical scheme of the invention is further improved as follows: the compatilizer is modified polytetrafluoroethylene micro powder, the modified polytetrafluoroethylene micro powder is prepared from polytetrafluoroethylene micro powder, a modified monomer and peroxide, and the mass ratio of the polytetrafluoroethylene micro powder to the modified monomer to the peroxide is 100: 0.1-1.0: 0.1-0.5; the average particle size D50 of the compatilizer is 1-20 microns, and the number average molecular weight is 5000-30000; the compatilizer is of a porous structure, and the porosity is 25-75%.

The technical scheme of the invention is further improved as follows: the modified monomer is any one of maleic anhydride, acrylic acid, methacrylic acid, fumaric acid and glycidyl methacrylate; the peroxide is any one of dicumyl peroxide, diacetyl peroxide, dibenzoyl peroxide, diisobutylene peroxide, tert-butyl dicumyl peroxide and tert-butyl acetate peroxide.

A preparation method of a high-density polyethylene pipe material mixing material comprises the following steps:

A. preparing a compatilizer: weighing polytetrafluoroethylene micro powder, a modified monomer and peroxide according to a preset proportion, adding the polytetrafluoroethylene micro powder, the modified monomer and the peroxide into a high-pressure reaction kettle, sealing, uniformly stirring, heating to 200 ℃, introducing supercritical carbon dioxide, controlling the pressure to be 20MPa, keeping for 10min, and relieving pressure;

B. preparing a mixed material: weighing high-density polyethylene, carbon black master batch and compatilizer in a preset proportion, uniformly mixing, and then extruding and processing by a double screw to granulate.

The technical scheme of the invention is further improved as follows: the temperature rising rate in the step A is 20 ℃/min, and supercritical carbon dioxide is introduced until the pressure of the reaction kettle is 20 MPa; and the temperature of the twin-screw extrusion processing in the step B is 200-210 ℃, and the rotating speed of the screw is 100-400 rpm.

Due to the adoption of the technical scheme, the invention has the technical progress that:

the preparation method of the pipe mixed material is simple, the prepared pipe mixed material has uniform dispersion of carbon black, and the prepared pipe also has the advantages of stable quality and long service life.

The compatilizer in the high-density polyethylene pipe mixing material is preferably modified polytetrafluoroethylene micro powder, the average grain diameter of the Polytetrafluoroethylene (PTFE) micro powder is less than 5 mu m, and the specific surface is more than 10m²The lubricant has the advantages of a friction coefficient of 0.06-0.07, good lubricity and capability of being well dispersed in a plurality of materials; can be used as an anti-sticking, anti-friction and flame-retardant additive for plastics, rubber, printing ink, paint and lubricating grease, and can also be used as a dry lubricant to be prepared into aerosol and the like; the PTFE micro powder product has the purity of 100 percent, the molecular weight of less than 1 ten thousand and the grain diameter of 0.5-15 mu m, not only maintains all the original excellent performances of the polytetrafluoroethylene, but also has a plurality of unique performances: such as no self-coagulation, no electrostatic effect, good intermiscibility, low molecular weight, good dispersibility, high self-lubricity, obvious reduction of friction coefficient and the like. The compatilizer prepared by mixing polytetrafluoroethylene micro powder, modified monomer and peroxide within the range defined by the invention according to a predetermined proportion and then carrying out high-temperature high-pressure preparation in supercritical carbon dioxide has high grafting efficiency and a porous structure, the porosity of the compatilizer can reach 25-75%, the pores of the prepared compatilizer are open pores, the surface of the compatilizer is communicated with the outside, the pores are uniformly distributed in the compatilizer, and the compatilizer has the advantages of uniform porosity and pore distribution under the optimal condition that the porosity and the pore distribution are uniformThe performance of improving the dispersion effect is optimal, so that the carbon black can be uniformly dispersed in the high-density polyethylene, and the bottleneck problem that the carbon black is difficult to uniformly disperse in a polyethylene matrix is solved. The compatibility agent has too small porosity and poor capability of improving the dispersion effect, the improvement of the porosity has higher requirements on the preparation process conditions of the compatibility agent, the production cost of enterprises can be greatly increased, and the performance of improving the dispersion effect cannot be improved too much due to too high porosity.

Drawings

FIG. 1 is a diagram showing the dispersion of carbon black in a compounding material obtained by a conventional PE pipe production method;

FIG. 2 is a graph showing the dispersion of carbon black in a compounded material obtained by the production method of the present invention.

Detailed Description

The present invention will be described in further detail with reference to the following examples:

the high-density polyethylene pipe mixing material comprises high-density polyethylene, carbon black master batch and a compatilizer, wherein the content of the carbon black master batch is 5% of the mass of the high-density polyethylene, the content of the compatilizer is 0.1-3.0% of the mass of the high-density polyethylene, and the content of the preferable compatilizer is 0.3-1.0% of the mass of the high-density polyethylene. The melt index of the high-density polyethylene under the conditions of 190 ℃ of temperature and 2.16kg of pressure is 0.01-2.50 g/10min, and the melt index of the preferred high-density polyethylene under the conditions of 190 ℃ of temperature and 2.16kg of pressure is 0.05-2.00 g/10 min; the carrier of the carbon black master batch is one or a mixture of two of linear low-density polyethylene and high-density polyethylene, the content of carbon black in the carbon black master batch is 30-60%, and the content of carbon black in the carbon black master batch is preferably 40-50%; the compatilizer is modified polytetrafluoroethylene micro powder and is of a porous structure, and the porosity of the compatilizer is 25-75%; the modified polytetrafluoroethylene micro powder is prepared from polytetrafluoroethylene micro powder, a modified monomer and peroxide, and the mass ratio of the polytetrafluoroethylene micro powder to the modified monomer to the peroxide is 100: 0.1-1.0: 0.1-0.5; the average particle size D50 of the compatilizer is 1-20 micrometers, the number average molecular weight is 5000-30000, and the modified monomer is any one of maleic anhydride, acrylic acid, methacrylic acid, fumaric acid and glycidyl methacrylate; the peroxide is any one of dicumyl peroxide, diacetyl peroxide, dibenzoyl peroxide, diisobutylene peroxide, tert-butyl dicumyl peroxide and tert-butyl acetate peroxide.

A preparation method of a high-density polyethylene pipe material mixing material comprises the following steps:

A. preparing a compatilizer: weighing polytetrafluoroethylene micro powder, a modified monomer and peroxide according to a preset proportion, adding the polytetrafluoroethylene micro powder, the modified monomer and the peroxide into a high-pressure reaction kettle, sealing, uniformly stirring, heating to 200 ℃, introducing supercritical carbon dioxide, controlling the pressure to be 20MPa, keeping for 10min, and relieving pressure; wherein supercritical carbon dioxide is introduced until the pressure of the reaction kettle is 20MPa, and the heating rate is 20 ℃/min;

B. preparing a mixed material: weighing high-density polyethylene, carbon black master batch and compatilizer in a preset proportion, uniformly mixing, and then extruding and processing and granulating by double screws, wherein the temperature during the extrusion and processing of the double screws is 200-210 ℃, and the rotating speed of the screws is 100-400 rpm.