CN113063038A

CN113063038A - Anti-scale fiber-reinforced beta-crystal-form PP-R composite pipe and preparation method thereof

Info

Publication number: CN113063038A
Application number: CN202110387553.7A
Authority: CN
Inventors: 赵春艳
Original assignee: Shanghai Weixing New Building Materials Co Ltd
Current assignee: Shanghai Weixing New Building Materials Co Ltd
Priority date: 2021-04-10
Filing date: 2021-04-10
Publication date: 2021-07-02

Abstract

The invention relates to an anti-scaling fiber reinforced beta-crystal form PP-R composite pipe and a preparation method thereof, and is characterized by comprising an outer layer, a middle layer and an inner layer, wherein the middle layer is arranged between the outer layer and the inner layer; the outer layer is beta-crystal-form random copolymer polypropylene (PP-R), the middle layer is beta-crystal-form PP-R enhanced by high-dispersion chopped glass fiber, and the inner layer is anti-scaling modified beta-crystal-form PP-R. The fiber reinforced layer resin provided by the invention adopts beta crystal form PP-R, so that the rigidity of the pipe, and the pressure resistance and bending resistance of the pipe are improved; the addition of the fluorine-containing modified beta-crystal form PP-R master batch reduces the surface energy and roughness of the inner wall of the pipe, improves the hydrophobicity and effectively reduces the adhesion of scale. The application can be used for cold and hot water pipeline systems in buildings, main vertical pipes in buildings, air-conditioning pipeline systems and other industrial pipes.

Description

Anti-scale fiber-reinforced beta-crystal-form PP-R composite pipe and preparation method thereof

Technical Field

The invention relates to the technical field of PP-R composite pipes, in particular to an anti-scale fiber-reinforced beta-crystal PP-R composite pipe and a preparation method thereof.

Background

Since plastic pipelines began to replace cast iron pipes and PVC water supply pipes in 1999, PP-R pipes rapidly occupy the whole indoor water supply pipeline market and become mainstream products in the market. Incomplete statistics, the PP-R percentage is over 80% throughout the indoor water supply pipeline market, but at the same time, some problems are also exposed. Such as the application of the product in the high temperature field, occasionally pipe explosion occurs, and the brittleness is larger in the winter. In some special fields, such as building main vertical pipes, products exist in domestic markets at present, such as steel-plastic composite pipes, plastic-lined steel pipes, stainless steel pipes and other products, and the former two products have the main problems of poor compatibility between plastics and metals and easy delamination due to poor adhesion; the problem that thin wall stainless steel pipe exists is that the connection reliability is low, mainly adopts the card to press the mode to carry out being connected of tubular product and pipe fitting, and the leakproofness all leans on inside EPT rubber circle, however the life-span of EPT rubber material in the hot water field is at most 20 years now, and how follow-up problem is solved and is become the biggest quality hidden danger. Therefore, a reinforced plastic pipeline product is urgently needed as a substitute to meet the requirements in the high-temperature and high-pressure field.

The beta crystal form nucleating agent can effectively solve the defect of insufficient rigidity of common random copolymerization polypropylene (PP-R), obviously improves the tensile strength and the flexural modulus of the PP-R, and improves the thermal deformation temperature of the PP-R by 10-15 ℃. As is well known, the glass fibers are added into the thermoplastic matrix resin, and the dispersed long-bundle fibers are inserted and connected in the matrix to form a network structure to play a role of framework support, so that the deformation resistance, the bending strength, the bending modulus and the thermal deformation temperature of the fiber reinforced composite material can be improved, and the linear expansion coefficient can be greatly reduced. However, the glass fiber is an inorganic material containing polar groups, and the interfacial compatibility between the glass fiber and the nonpolar organic polymer PP-R is poor, which greatly affects the comprehensive performance of the fiber reinforced composite material.

Although the PP-R material is sanitary and nontoxic, the PP-R material does not have antibacterial capability and cannot treat bacteria, organic compounds and heavy metal ions. In the actual transportation process of cold and hot water in a building, oxygen in the atmosphere easily permeates into the interior of a pipeline system through the pipe wall, pipe fittings and other parts made of metal materials connected with a PP-R pipe are corroded, microorganisms are bred due to the permeation of the oxygen, the transported water quality is adversely affected, and in addition, scales are easily formed to block the pipeline.

The organic fluorine material is the most commonly used low surface energy material and has excellent oil transportation hydrophobicity, self-cleaning property and antifouling property. However, the interfacial compatibility between the polyolefin resin and the resin is poor, and a good dispersion effect is difficult to achieve by adopting a direct physical blending mode.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provides an anti-scaling fiber reinforced beta-crystal form PP-R composite pipe and a preparation method thereof.

The purpose of the invention is realized by the following technical scheme:

an anti-scale fiber reinforced beta-crystal form PP-R composite pipe is characterized by comprising an outer layer, an intermediate layer and an inner layer, wherein the intermediate layer is arranged between the outer layer and the inner layer; the outer layer is made of beta-crystal form PP-R, and the middle layer is made of high-dispersion chopped glass fiber reinforced beta-crystal form PP-R; the inner layer of the pipe is made of anti-scaling modified beta-crystal form PP-R.

The outer layer of the pipe is made of beta-crystal form PP-R, so that the hot-melt connectivity of the plastic pipeline is ensured.

The middle layer of the pipe is made of beta-crystal form PP-R reinforced by high-dispersion chopped glass fibers, the mass part of the high-dispersion chopped glass fibers in the middle layer is 5-30 parts, and the length of the fibers is 2-8 mm; the middle layer of the pipe is a product reinforcing layer, and the addition of the high-dispersion chopped glass fiber can enhance the rigidity of the pipe and improve the pressure resistance of the pipe; the high-dispersion chopped glass fiber is a pretreated chopped glass fiber, and can enhance the compatibility of the fiber and the beta-crystal form PP-R particles.

The inner layer of the pipe is made of anti-scaling modified beta-crystal form PP-R, the anti-scaling modified beta-crystal form PP-R takes beta-crystal form PP-R as a raw material, fluorine-containing modified beta-crystal form PP-R master batches are added into the raw material, the raw material and the master batches are mixed by a high-speed mixer, and a high-mixing screw extruder is used for carrying out melt blending and granulation to prepare the anti-scaling modified beta-crystal form PP-R; the inner layer of the pipe is a product functional layer, and the surface energy of the inner layer material of the pipe is reduced by adding the fluorine-containing modified beta-crystal form PP-R master batch, so that the hydrophobicity and the antifouling property are improved, and the deposition of dirt on the inner wall of the pipe is reduced.

The preparation method of the outer layer material of the pipe comprises the following specific steps:

taking PP-R as a raw material, stirring the PP-R, a beta crystal form nucleating agent, a hindered phenol heat stabilizer, calcium stearate and white oil by a high-speed mixer, and carrying out melt blending and granulation by a high-mixing screw extruder to prepare the beta crystal form PP-R; wherein, based on 100 parts by weight of PP-R, the content of the beta crystal form nucleating agent is 0.05-5 parts, the content of the hindered phenol heat stabilizer is 0.1-10 parts, the content of the calcium stearate is 0.1-5 parts, and the content of the white oil is 0.1-5 parts.

The PP-R is resin with the density of 0.9-0.92 g/cm3 and the melt index of 0.2-0.5 g/10 min; in the prepared beta-crystal form PP-R, the content of the beta-crystal form reaches 60-75%; the impact strength of the beta-crystal form PP-R material is obviously improved; the melting temperature of the material was measured by differential scanning calorimetry and a distinct double peak appeared.

The preparation method of the pipe intermediate layer material comprises the following specific steps:

taking 100 parts by weight of beta-crystal form PP-R as a raw material, adding 0.1-5 parts of antioxidant, 5-30 parts of high-dispersion chopped glass fiber with the length of 2-8 mm, 0.1-10 parts of compatilizer and 0.1-5 parts of white oil, and stirring by adopting a high-speed mixer for 5-15 min at a stirring speed of 200-250R/min; a high-mixing screw extruder is adopted for melt blending, the temperature of the melting section of the extruder is controlled to be 180-220 ℃, the vacuum degree is controlled to be 0.008-0.03 MPa, the temperature of a cooling water tank is controlled to be 30-60 ℃, and the length of the cooling water tank is controlled to be 2-4 m; granulating by a granulator to prepare high-dispersion chopped glass fiber reinforced beta-crystal form PP-R;

the high-dispersion chopped glass fiber reinforced beta-crystal form PP-R has the density range: 1.0-1.2 g/cm3, a melt index of 0.4-0.55 g/10min, and an ash content of 5-30%.

The compatilizer is maleic anhydride grafted polypropylene and is a conventional polypropylene compatilizer.

The preparation method of the high-dispersion chopped glass fiber comprises the following specific steps:

placing 1-10 parts of polyethylene wax in an environment at 90-120 ℃ to soften the polyethylene wax into a liquid state, then soaking 0.5-5 parts of chopped glass fibers with the length of 4-8 mm in the polyethylene wax for processing for 1-10 min, meanwhile, maintaining the state of the polyethylene wax to be the liquid state, then adding 0.1-5 parts of TAF (polyethylene glycol) anti-glass fiber external exposure agent powder into the polyethylene wax and stirring uniformly, taking out the dipped chopped glass fibers, naturally cooling, and then placing the cooled dipped chopped glass fibers in a mortar for grinding and dispersing to obtain the high-dispersion chopped glass fibers.

The preparation method of the inner layer material of the pipe comprises the following specific steps:

taking 100 parts by weight of beta-crystal form PP-R as a raw material, adding 1-20 parts by weight of fluorine-containing modified beta-crystal form PP-R master batch, mixing by a high-speed mixer, and performing melt blending and granulation by a high-mixing screw extruder to prepare the anti-scaling modified beta-crystal form PP-R.

The preparation method of the fluorine-containing modified beta-crystal PP-R master batch comprises the following specific steps:

beta-crystal form PP-R is taken as a raw material, and is dried for later use. 0.1-1 part of dicumyl peroxide is dissolved in 1-10 parts of styrene, 5-25 parts of fluorine-containing monomer is added, and the mixture is uniformly mixed with 100 parts of dried beta-crystal form PP-R in a high-speed mixer for 5-30 min. Carrying out melt grafting, extrusion, drafting, cooling, grain cutting and drying on the mixed raw materials in a double-screw extruder, and purifying to obtain fluorine-containing modified beta-crystal form PP-R master batches; the melting temperature of the double-screw extruder is set to be 160-190 ℃, and the rotating speed of the screw is 70 rpm.

The fluorine-containing monomer is a fluorine-containing acrylate compound. Common fluorine-containing acrylate compounds include decahexafluorononyl acrylate (surface tension of 13mN/m), dodecafluoroheptyl methacrylate (surface tension of 18mN/m), perfluoroalkylethyl methacrylate, and the like.

The inner layer of the pipe ensures good sanitary performance when the pipe is used for delivering water, has an anti-scaling function and completely meets the requirements of drinking water materials.

The anti-scaling fiber reinforced beta-crystal form PP-R composite pipe and the preparation method thereof are characterized in that various raw materials of the inner layer, the middle layer and the outer layer are subjected to melt co-extrusion through three single-screw extruders, the sleeve temperature is 30-70 ℃, the head temperature is 200 +/-20 ℃, the die head temperature is 220 +/-20 ℃, and the screw rotating speeds of the three single-screw extruders are controlled so as to control the extrusion amount of three layers of materials, so that the thickness ratio of the three layers of the inner layer, the middle layer and the outer layer is 1:1: 1.

An anti-scaling double-layer beta-crystal form PP-R composite pipe is characterized by comprising an inner layer and an outer layer, wherein the wall thickness ratio of the inner layer to the outer layer is 1: 4; the inner layer material is anti-scaling modified beta-crystal form PP-R, and the outer layer material is beta-crystal form PP-R; the anti-scaling modified beta-crystal form PP-R is prepared by taking beta-crystal form PP-R as a raw material, adding fluorine-containing modified beta-crystal form PP-R master batches, and performing blending extrusion; the mass fraction of the fluorine-containing modified beta-crystal form PP-R master batch in the inner layer material is 1-20 parts.

The preparation method of the fluorine-containing modified beta-crystal PP-R master batch is the same as the steps.

Compared with the prior art, the invention has the following positive effects:

the bi-oriented anti-scaling fiber reinforced beta-crystal PP-R composite pipe with the anti-scaling function has the advantages that: the pressure resistance of the pipe and the rigidity of the pipe are improved by introducing the high-dispersion chopped glass fiber reinforced beta-crystal form PP-R layer, and the linear expansion coefficient of the product is obviously reduced; by adjusting the length of the high-dispersion chopped glass fiber, the linear expansion coefficient of the composite pipe can be reduced to 1/3-1/4 of that of a common PP-R pipe on the premise of meeting high pressure resistance. Secondly, the appearance of the beta crystal form PP-R enables the spherulite size in the material to be refined, the low-temperature impact property of the material to be greatly improved, the problem of low-temperature brittleness of the PP-R material is solved, and the pressure resistance of the product is improved; and finally, the fluorine-containing modified beta-crystal PP-R master batch is added, so that when the pipeline conveys drinking water, dirt is not easy to deposit or adhere to the interior of the pipeline, the aim of preventing scaling is fulfilled, and the sanitary performance is better. The invention can be used for cold and hot water pipeline systems in buildings, main riser systems of buildings, air-conditioning pipeline systems and other industrial pipes.

Drawings

Fig. 1 is a schematic structural diagram of embodiment 1 of the present application:

the reference numbers in the drawings are respectively:

1 an inner layer of a thermoplastic resin composition,

2 a middle layer and a bottom layer,

and 3, outer layer.

Detailed Description

The following provides a specific embodiment of the anti-scale fiber reinforced beta-crystal form PP-R composite pipe and the preparation method thereof.

Example 1

Referring to the attached figure 1, the anti-scale fiber reinforced beta-crystal form PP-R composite pipe is characterized by comprising an outer layer 3, an intermediate layer 2 and an inner layer 1, wherein the intermediate layer is arranged between the outer layer and the inner layer; the outer layer is made of beta-crystal form PP-R, and the middle layer is made of high-dispersion chopped glass fiber reinforced beta-crystal form PP-R; the inner layer of the pipe is made of anti-scaling modified beta-crystal form PP-R.

The middle layer of the pipe is made of beta-crystal form PP-R reinforced by high-dispersion chopped glass fibers, the mass part of the high-dispersion chopped glass fibers in the middle layer is 5-30 parts, and the length of the fibers is 2-8 mm; the middle layer of the pipe is a product reinforcing layer, and the addition of the high-dispersion chopped glass fiber enhances the rigidity of the pipe and improves the pressure resistance of the pipe; the high-dispersion chopped glass fiber is a pretreated chopped glass fiber, and can enhance the compatibility of the fiber and the beta-crystal form PP-R particles.

The inner layer of the pipe is made of anti-scaling modified beta-crystal form PP-R, the anti-scaling modified beta-crystal form PP-R takes beta-crystal form PP-R as a raw material, fluorine-containing modified beta-crystal form PP-R master batches are added into the raw material, the raw material and the master batches are mixed by a high-speed mixer, and a high-mixing screw extruder is used for carrying out melt blending and granulation to prepare the anti-scaling modified beta-crystal form PP-R; the inner layer of the pipe is a product functional layer, and the surface energy of the inner layer material of the pipe is reduced by adding the fluorine-containing modified beta-crystal form PP-R master batch, so that the hydrophobicity and antifouling property of the inner layer material are improved, and the deposition of dirt on the inner wall of the pipe is reduced.

PP-R is taken as a raw material, and is stirred with a beta crystal form nucleating agent, a hindered phenol heat stabilizer, calcium stearate and white oil through a high-speed mixer, and a high-mixing screw extruder is adopted for melt blending and granulation to prepare the beta crystal form PP-R. Wherein, based on 100 parts by weight of PP-R, the content of the beta crystal form nucleating agent is 1.0 part, the content of the hindered phenol heat stabilizer is 0.5 part, the content of the calcium stearate is 0.5 part, and the content of the white oil is 1.0 part.

The PP-R is resin with the density of 0.9-0.92 g/cm3 and the melt index of 0.4-0.5 g/10 min.

taking 100 parts by weight of beta-crystal form PP-R as a raw material, adding 0.5 part of antioxidant, 30 parts of high-dispersion chopped glass fiber with the length of 4-8 mm, 5 parts of compatilizer and 0.5 part of white oil, and stirring by adopting a high-speed mixer for 5min at a stirring speed of 200R/min; adopting a high-mixing screw extruder to carry out melt blending, wherein the temperature of the melting section of the extruder is controlled to be 180-210 ℃, the vacuum degree is controlled to be 0.01-0.02MPa, the temperature of a cooling water tank is controlled to be 35-55 ℃, and the length of the cooling water tank is controlled to be 2.5-3.5 m; granulating by a granulator to prepare high-dispersion chopped glass fiber reinforced beta-crystal form PP-R;

placing 2.5 parts of polyethylene wax in an environment at 95 ℃ to soften the polyethylene wax into a liquid state, then soaking 2 parts of chopped glass fibers with the length of 4-8 mm in the polyethylene wax for treatment for 5min, meanwhile, maintaining the state of the polyethylene wax to be the liquid state, then adding 1.3 parts of TAF (polyethylene glycol ether) glass fiber exposure preventing agent powder into the polyethylene wax and uniformly stirring, then taking out the chopped glass fibers subjected to the soaking treatment, naturally cooling, and then placing the cooled soaked chopped glass fibers in a mortar for grinding and dispersing to obtain the high-dispersion chopped glass fibers.

100 parts by weight of beta-crystal form PP-R are taken as a raw material, 6 parts of fluorine-containing modified beta-crystal form PP-R master batch are added, a high-speed stirrer is used for mixing, and a high-mixing screw extruder is used for carrying out melt blending and granulation to prepare the anti-scaling modified beta-crystal form PP-R.

beta-crystal form PP-R is taken as a raw material, and is dried for later use. 0.5 part of dicumyl peroxide is dissolved in 5 parts of styrene, 20 parts of fluorine-containing monomer of dodecafluorononyl acrylate is added, and the mixture is uniformly mixed with 100 parts of dried beta-crystal form PP-R in a high-speed mixer for 20 min. Carrying out melt grafting, extrusion, drafting, cooling, grain cutting and drying on the mixed raw materials in a double-screw extruder, and purifying to obtain fluorine-containing modified beta-crystal form PP-R master batches; the melting temperature of the double-screw extruder is set to be 160-190 ℃, and the rotating speed of the screw is 70 rpm.

A preparation method of an anti-scaling fiber reinforced beta-crystal form PP-R composite pipe comprises the steps of carrying out melt co-extrusion on various raw materials of an inner layer, a middle layer and an outer layer through three single-screw extruders, controlling the screw rotating speeds of the three single-screw extruders to control the extrusion amounts of three layers of materials, wherein the sleeve temperature is 35-50 ℃, the head temperature is 200 +/-20 ℃, the die head temperature is 220 +/-20 ℃, and the thickness ratio of the three layers of the inner layer, the middle layer and the outer layer is 1:1: 1.

And (3) performance testing:

the contact angle of the inner layer material of the anti-scale fiber reinforced beta-crystal form PP-R composite pipe is 109.4 degrees, and the surface roughness is 0.043 mu m. By adopting a chemical titration method, the fluorine-containing grafting rate of the fluorine-containing modified beta-crystal form PP-R master batch can reach 6.2 percent.

And testing the beta crystal form PP-R by adopting an X-ray diffraction method, and finding that the beta crystal form content is 61-65%. The impact strength of the beta-crystal form PP-R material is obviously improved; the melting temperature of the beta-crystal form PP-R material is tested by a differential scanning calorimeter, and an obvious double peak appears, which indicates that the preparation of the beta-crystal form PP-R is successful.

The density test result of the high-dispersion chopped glass fiber reinforced beta-crystal form PP-R material is 1.08g/cm3, the melt index is 0.45-0.49 g/10min, and the ash content is 20-23%; the bending strength is more than or equal to 40MPa, the bending modulus is more than or equal to 1500MPa, and the impact strength of a simply supported beam notch is more than or equal to 8kJ/m 2.

The hydrostatic pressure test result of the anti-scale fiber reinforced beta-crystal form PP-R composite pipe is as follows: 20 ℃, 17MPa, 1h, 95 ℃, 4.5MPa, 22h, 95 ℃, 4.0MPa, 1000 h; no damage and no infiltration. The axial linear expansion coefficient of the composite pipe is 0.04-0.05 mm/m DEG C.

Example 2

The preparation of the beta crystal form PP-R and the preparation of the beta crystal form PP-R reinforced by the highly dispersed chopped glass fiber are the same as in example 1.

beta-crystal form PP-R is taken as a raw material, and is dried for later use. 0.5 part of dicumyl peroxide is dissolved in 5 parts of styrene, 20 parts of dodecafluoroheptyl methacrylate are added, and the mixture is uniformly mixed with 100 parts of dried beta-crystal form PP-R in a high-speed mixer for 20 min. Carrying out melt grafting, extrusion, drafting, cooling, grain cutting and drying on the mixed raw materials in a double-screw extruder, and purifying to obtain fluorine-containing modified beta-crystal form PP-R master batches; the melting temperature of the double-screw extruder is set to be 160-190 ℃, and the rotating speed of the screw is 70 rpm.

And (3) performance testing:

the contact angle of the inner layer material of the anti-scale fiber reinforced beta-crystal form PP-R composite pipe is 104.6 degrees, and the surface roughness is 0.048 mu m. The fluorine-containing grafting rate of the fluorine-containing modified beta-crystal PP-R master batch is tested to be 5.1% by adopting a chemical titration method. Compared with the example 1, the contact angle of the inner layer material is reduced by 4.4%, the fluorine-containing grafting rate of the fluorine-containing modified beta-crystal form PP-R master batch is reduced by 17.7%, namely the anti-scaling effect is reduced. The shorter the side chain containing fluorine in the grafting monomer is, the more unfavorable the ordered arrangement of the fluorine-containing unit in the polymer is, the lower the fluorine content of the fluorine-containing modified polymer is, and the weaker the water repellency is.

The hydrostatic pressure test result of the anti-scale fiber reinforced beta-crystal form PP-R composite pipe is as follows: 20 ℃, 17MPa, 1h, 95 ℃, 4.5MPa, 22h, 95 ℃, 4.0MPa, 1000 h; no damage and no infiltration. The axial linear expansion coefficient of the composite pipe is 0.043 mm/m.

Example 3

A fiber reinforced beta-crystal form PP-R composite pipe comprises an outer layer, an intermediate layer and an inner layer, wherein the intermediate layer is arranged between the outer layer and the inner layer; the inner layer and the outer layer are made of beta-crystal PP-R, and the middle layer is made of high-dispersion chopped glass fiber reinforced PP-R.

The inner layer and the outer layer of the pipe are made of beta-crystal form PP-R, so that the hot-melt connectivity of the plastic pipeline is ensured.

The middle layer of the pipe is made of high-dispersion chopped glass fiber reinforced PP-R, the mass part of the high-dispersion chopped glass fiber in the middle layer is 5-30 parts, and the length of the fiber is 2-8 mm; the middle layer of the pipe is a product reinforcing layer, and the addition of the high-dispersion chopped glass fiber enhances the rigidity of the pipe and improves the pressure resistance of the pipe; the high-dispersion chopped glass fiber is a pretreated chopped glass fiber and can enhance the compatibility of the fiber and the PP-R particles.

The preparation of beta-crystalline PP-R is as in example 1.

taking 100 parts by weight of PP-R as a raw material, adding 0.5 part of antioxidant, 30 parts of high-dispersion chopped glass fiber with the length of 4-8 mm, 5 parts of compatilizer and 0.5 part of white oil, and stirring by adopting a high-speed mixer for about 5min at a stirring speed of 200R/min; adopting a high-mixing screw extruder to carry out melt blending, wherein the temperature of the melting section of the extruder is controlled to be 180-210 ℃, the vacuum degree is controlled to be 0.01-0.02MPa, the temperature of a cooling water tank is controlled to be 35-55 ℃, and the length of the cooling water tank is controlled to be 2.5-3.5 m; cutting the mixture into granules by a granulator to prepare the high-dispersion chopped glass fiber reinforced PP-R;

A preparation method of a fiber reinforced beta-crystal form PP-R composite pipe comprises the steps of carrying out melt co-extrusion on various raw materials of an inner layer, an intermediate layer and an outer layer through three single-screw extruders, controlling the extrusion amount of three layers of materials by controlling the screw rotation speed of the three single-screw extruders at the sleeve temperature of 35-50 ℃, the head temperature of 200 +/-20 ℃ and the die head temperature of 220 +/-20 ℃, and enabling the thickness ratio of the three layers of the inner layer, the intermediate layer and the outer layer to be 1:1: 1.

And (3) performance testing:

the contact angle of the inner layer material of the fiber reinforced beta-crystal form PP-R composite pipe is 94.8 degrees, and the surface roughness is 0.47 mu m. Compared with example 1, the contact angle of the inner layer material is obviously reduced, and the surface roughness is obviously increased.

The density test result of the high-dispersion chopped glass fiber reinforced PP-R material is 1.07g/cm3, the melt index is 0.43-0.47 g/10min, and the ash content is 20-23%; the bending strength is more than or equal to 40MPa, the bending modulus is more than or equal to 1500MPa, and the impact strength of a simply supported beam notch is more than or equal to 8kJ/m 2.

The hydrostatic pressure test result of the fiber reinforced beta-crystal form PP-R composite pipe is as follows: 20 ℃, 17MPa, 1h, 95 ℃, 4.3MPa, 22h, 95 ℃, 3.8MPa, 1000 h; no damage and no infiltration. The axial linear expansion coefficient of the composite pipe is 0.046 mm/m.

Compared with the example 1, the fiber reinforced beta-crystal form PP-R composite pipe has no fluorine-containing modified beta-crystal form PP-R master batch added to the inner layer of the pipe, and has no self-cleaning and anti-scaling functions; and compared with the example 1, the middle layer is the fiber-reinforced common PP-R, the crystal form conversion is not carried out, the hot water hydrostatic pressure test index of the pipe is reduced, and the manufacturing cost of the product is reduced.

Example 4

A fiber reinforced beta-crystal form PP-R composite pipe comprises an outer layer, an intermediate layer and an inner layer, wherein the intermediate layer is arranged between the outer layer and the inner layer; the inner layer and the outer layer are made of beta-crystal form PP-R, and the middle layer is made of common chopped glass fiber reinforced beta-crystal form PP-R.

The middle layer of the pipe is made of common chopped glass fiber reinforced beta-crystal form PP-R, the common chopped glass fiber is 5-30 parts by weight in the middle layer, and the length of the fiber is 2-8 mm; the middle layer of the pipe is a product reinforcing layer, and the rigidity of the pipe is enhanced and the pressure resistance of the pipe is improved by adding the common chopped glass fiber.

The preparation of beta-crystalline PP-R is as in example 1.

taking 100 parts by weight of PP-R as a raw material, adding 0.5 part of antioxidant, 30 parts of common chopped glass fiber with the length of 4-8 mm, 5 parts of compatilizer and 0.5 part of white oil, and stirring by adopting a high-speed mixer for 5min at a stirring speed of 200R/min; adopting a high-mixing screw extruder to carry out melt blending, wherein the temperature of the melting section of the extruder is controlled to be 180-210 ℃, the vacuum degree is controlled to be 0.01-0.02MPa, the temperature of a cooling water tank is controlled to be 35-55 ℃, and the length of the cooling water tank is controlled to be 2.5-3.5 m; cutting the mixture into granules by a granulator to prepare common chopped glass fiber reinforced beta-crystal form PP-R;

And (3) performance testing:

the contact angle of the inner layer material of the fiber reinforced beta-crystal form PP-R composite pipe is 94.8 degrees, and the surface roughness is 0.47 mu m. Compared with example 1, the contact angle of the inner layer material is obviously reduced, and the increase amplitude of the surface roughness is obvious.

The density test result of the common glass fiber reinforced beta-crystal form PP-R material is 1.08g/cm3, the melt index is 0.45-0.49 g/10min, and the ash content is 20-23%; the bending strength is 39MPa, the bending modulus is more than or equal to 1500MPa, and the impact strength of a simply supported beam notch is 7.7kJ/m 2.

The hydrostatic pressure test result of the fiber reinforced beta-crystal form PP-R composite pipe is as follows: 20 ℃, 17MPa, 1h, 95 ℃, 4.5MPa, 22h, 95 ℃, 3.8MPa, 1000 h; no damage and no infiltration. The axial linear expansion coefficient of the composite pipe is 0.044 mm/m.

Compared with the example 1, the fiber reinforced beta-crystal form PP-R composite pipe has no fluorine-containing modified beta-crystal form PP-R master batch added to the inner layer of the pipe, and has no self-cleaning and anti-scaling functions; compared with the example 1, the middle layer is the common chopped fiber reinforced beta-crystal form PP-R, the fiber is not pretreated, the hydrostatic hot water pressure test index of the pipe is reduced, and the manufacturing cost of the product is reduced.

Example 5

The application also provides an anti-scaling double-layer beta-crystal form PP-R composite pipe which is characterized by being divided into an inner layer and an outer layer, wherein the wall thickness ratio of the inner layer to the outer layer is 1: 4; the inner layer material is anti-scaling modified beta-crystal form PP-R, and the outer layer material is beta-crystal form PP-R.

The preparation of the beta crystalline form PP-R, the anti-fouling modified beta crystalline form PP-R, is the same as in example 1.

And (3) performance testing:

the contact angle of the inner layer material of the anti-scaling double-layer beta-crystal form PP-R composite pipe is 109.4 degrees, and the surface roughness is 0.043 mu m. By adopting a chemical titration method, the fluorine-containing grafting rate of the fluorine-containing modified beta-crystal form PP-R master batch can reach 6.2 percent.

The hydrostatic pressure test result of the anti-scale double-layer beta-crystal form PP-R composite pipe is as follows: 20 ℃, 17MPa, 1h, 95 ℃, 4.3MPa, 22h, 95 ℃, 3.8MPa, 1000 h; no damage and no infiltration. The axial linear expansion coefficient of the composite pipe is 0.15 mm/m.

Compared with the embodiment 1, the pipe is not reinforced by the middle layer, the hot water hydrostatic pressure test index of the pipe is reduced, and the manufacturing process is simple; and the ratio of the inner layer to the outer layer is set to be 1:4, and the inner surface of the pipe is only contacted with drinking water, so that the inner scale prevention layer does not need to be made thick, the manufacturing cost is low, and the pipe is easy to accept in the market.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, several modifications and decorations can be made without departing from the concept of the present invention, and these modifications and decorations should also be regarded as being within the protection scope of the present invention.

Claims

1. An anti-scale fiber reinforced beta-crystal form PP-R composite pipe is characterized by comprising an outer layer, an intermediate layer and an inner layer, wherein the intermediate layer is arranged between the outer layer and the inner layer; the outer layer is made of beta-crystal form PP-R, and the middle layer is made of high-dispersion chopped glass fiber reinforced beta-crystal form PP-R; the inner layer of the pipe is made of anti-scaling modified beta-crystal form PP-R.

2. The anti-scaling fiber reinforced beta-crystal form PP-R composite pipe according to claim 1, wherein the inner layer of the pipe is made of anti-scaling modified beta-crystal form PP-R, the anti-scaling modified beta-crystal form PP-R takes beta-crystal form PP-R as a raw material, fluorine-containing modified beta-crystal form PP-R master batches are added, the mixture is mixed by a high-speed mixer, and the mixture is prepared by melt blending and granulation by a high-mixing screw extruder.

3. The anti-scaling fiber reinforced beta-crystal form PP-R composite pipe according to claim 1, wherein the preparation method of the outer layer material of the pipe comprises the following specific steps:

4. The anti-scaling fiber reinforced beta-crystal form PP-R composite pipe according to claim 1, wherein the PP-R has a density of 0.9-0.92 g/cm³A resin with a melt index of 0.2-0.5 g/10 min; in the prepared beta-crystal form PP-R, the content of the beta-crystal form reaches 60-75%.

5. The anti-scaling fiber reinforced beta-crystal form PP-R composite pipe according to claim 1, wherein the preparation method of the pipe intermediate layer material comprises the following specific steps:

taking 100 parts by weight of beta-crystal form PP-R as a raw material, adding 0.1-5 parts of antioxidant, 5-30 parts of high-dispersion chopped glass fiber with the length of 2-8 mm, 0.1-10 parts of compatilizer and 0.1-5 parts of white oil, and stirring by adopting a high-speed mixer for 5-15 min at a stirring speed of 200-250R/min; a high-mixing screw extruder is adopted for melt blending, the temperature of the melting section of the extruder is controlled to be 180-220 ℃, the vacuum degree is controlled to be 0.008-0.03 MPa, the temperature of a cooling water tank is controlled to be 30-60 ℃, and the length of the cooling water tank is controlled to be 2-4 m; and granulating by a granulator to obtain the high-dispersion chopped glass fiber reinforced beta-crystal form PP-R.

6. The anti-scaling fiber reinforced beta-crystal form PP-R composite pipe according to claim 1, wherein the high-dispersion chopped glass fiber reinforced beta-crystal form PP-R has a density range of: 1.0-1.2 g/cm3, a melt index of 0.4-0.55 g/10min, and an ash content of 5-30%.

7. The anti-scaling fiber reinforced beta-crystal form PP-R composite pipe as claimed in claim 1, wherein the preparation method of the high-dispersion chopped glass fiber comprises the following specific steps:

8. The anti-scaling fiber reinforced beta-crystal form PP-R composite pipe according to claim 1, wherein the preparation method of the inner layer material of the pipe comprises the following specific steps:

taking 100 parts by weight of beta-crystal form PP-R as a raw material, adding 1-20 parts of fluorine-containing modified beta-crystal form PP-R master batch, mixing by using a high-speed mixer, and performing melt blending and granulation by using a high-mixing screw extruder to prepare the anti-scaling modified beta-crystal form PP-R;

taking beta-crystal form PP-R as a raw material, and drying the beta-crystal form PP-R for later use; dissolving 0.1-1 part of dicumyl peroxide in 1-10 parts of styrene, adding 5-25 parts of fluorine-containing monomer, and uniformly mixing with 100 parts of dried beta-crystal form PP-R in a high-speed mixer for 5-30 min; carrying out melt grafting, extrusion, drafting, cooling, grain cutting and drying on the mixed raw materials in a double-screw extruder, and purifying to obtain fluorine-containing modified beta-crystal form PP-R master batches; therefore, the melting temperature of the double-screw extruder is set to be 160-190 ℃, and the rotating speed of the screw is 70 rpm;

the fluorine-containing monomer is a fluorine-containing acrylate compound.

9. The preparation method of the anti-scaling fiber reinforced beta-crystal form PP-R composite pipe as claimed in claim 1, wherein the raw materials of the inner layer, the middle layer and the outer layer are subjected to melt co-extrusion through three single-screw extruders, the sleeve temperature is 30-70 ℃, the nose temperature is 200 +/-20 ℃, the die head temperature is 220 +/-20 ℃, and the screw rotation speeds of the three single-screw extruders are controlled to control the extrusion amount of the three layers of materials, so that the thickness ratio of the three layers of the inner layer, the middle layer and the outer layer is 1:1: 1.

10. An anti-scaling double-layer beta-crystal form PP-R composite pipe is characterized by comprising an inner layer and an outer layer, wherein the wall thickness ratio of the inner layer to the outer layer is 1: 4; the inner layer material is anti-scaling modified beta-crystal form PP-R, and the outer layer material is beta-crystal form PP-R; the anti-scaling modified beta-crystal form PP-R is prepared by taking beta-crystal form PP-R as a raw material, adding fluorine-containing modified beta-crystal form PP-R master batches, and performing blending extrusion; the mass fraction of the fluorine-containing modified beta-crystal form PP-R master batch in the inner layer material is 1-20 parts.