KR20110034979A - High temperature pipe - Google Patents

Abstract

PURPOSE: A high-temperature pipe is provided to maintain high heat distortion temperature and improve processibility and formability with maintaining the property of matter of a single plastic material. CONSTITUTION: A high temperature pipe(1) comprises an internal layer(10) of 80~90wt.% and an outer layer(20) of 10~20 wt.%. The internal layer comprises PE- RT(Polyethylene Raised Temperature). The outer layer covers the internal layer. The outer layer contains HDPE(High Density Polyethylene) and master batch, and the weight ratio thereof is 1.5~2.0:1.

Description

High Temperature Pipe

The present invention relates to a high temperature pipe, and in particular, a high density polyethylene (HDPE) having excellent processability and moldability is mixed with a polyethylene raised temperature (PE-RT) raw material which is excellent in heat resistance to produce a single tube or multilayer tube. The present invention relates to a high temperature pipe having a high deformation temperature, which does not cause physical and chemical changes even at high temperatures, and which has excellent impact resistance, flexibility, processability, and formability.

Currently, polyethylene pipe or polypropylene pipe produced as a synthetic resin product is not used for high temperature, so it is used as a stainless steel pipe (sus pipe) or general steel pipe, and general resin pipe is used at room temperature and pipe life when using a high temperature fluid Shortening and connecting parts are not used due to incompatibility.

Therefore, in terms of technology development for utilizing renewable energy, it is required to develop pipes, which are construction materials, and accessories that connect pipes. However, until now, existing steel pipes are mainly used, and synthetic resin pipes can be conveniently used. Development is not ongoing.

In addition, the state of the art in the domestic and foreign countries as a high-temperature pipe is released only a small diameter pipe system for hot water supply and hot water pipes, the medium diameter or large diameter pipe is hardly produced.

Therefore, there is a need for further research on high-temperature pipes that can be used as large-diameter pipes for cooling and heating pipes for special crop cultivation, main pipes for renewable energy, and power plants using seawater.

In order to solve the problems of the prior art as described above, an object of the present invention is to provide a high temperature pipe that is resistant to high temperature and heat, and excellent in impact resistance and flexibility.

It is also an object of the present invention to provide a high temperature pipe having the physical properties of a single plastic material and at the same time significantly improving workability and formability.

In addition, an object of the present invention is to provide a high-temperature pipe capable of producing large diameter pipes with strong internal pressure at high and low temperatures, such as water supply, hot water supply, and ondol.

In order to achieve the above object, the present invention a) an inner layer comprising a polyethylene raised temperature (PE-RT); And b) an outer layer formed to surround the inner layer, the outer layer comprising a high density polyethylene (HDPE) and a masterbatch.

In particular, the inner layer and the outer layer is preferably formed in a weight ratio of 80 ~ 90:10 ~ 20 to the total weight of the pipe.

In another aspect, the present invention provides a high-temperature pipe, characterized in that it comprises a polyethylene raised temperature (PE-RT), high density polyethylene (HDPE), masterbatch and additives.

Specifically, the pipe is preferably contained in 80 to 90 parts by weight of PE-RT, 10 to 20 parts by weight of high density polyethylene and 5.0 to 6.25 parts by weight of the master batch relative to the total weight of the pipe.

The high temperature pipe of the present invention is a mixture of PE-RT and high-density polyethylene, which is manufactured as an alloy single-layer or multi-layer tube, so that the thermal deformation temperature is high, so that no physical and chemical changes occur at high temperatures, and the impact resistance and flexibility are excellent. There is this. In addition, the high temperature pipe of the present invention has the physical properties of a single plastic material and at the same time the workability and formability is remarkably improved, the pressure resistance is strong at high and low temperatures, such as for water supply, hot water supply, ondol, and can be produced in a large diameter.

Hereinafter, the present invention will be described in detail.

The inventors of the present invention manufacture a single-layer tube using a PE-RT raw material having excellent heat resistance and a polymer having excellent heat resistance obtained by reforming a high density polyethylene (HDPE) having excellent processability and moldability with a polymer alloy. As the inner layer was formed by -RT and the outer layer was formed to cover the surface with high density polyethylene, the multilayer tube was manufactured. As a result, it is possible to manufacture a large diameter pipe of 100 to 200 mm, and the pressure resistance at high and low temperatures is strong. It was confirmed that the workability and formability are remarkably improved and completed the present invention.

The high temperature pipe of the present invention is formed to surround the inner layer and the inner layer made of polyethylene raised temperature (PE-RT), and configured to include an outer layer made of high density polyethylene (HDPE) and masterbatch It is characterized by a layered pipe.

The PE-RT forming the inner layer is a polyethylene-based synthetic resin having excellent heat resistance, and the inner layer may further include additives such as impact modifiers, fluidity improvers, and antioxidants to increase heat resistance and reforming performance in addition to the resin component of PE-RT. have.

Specifically, the impact modifier may be a methyl methacrylate butadiene styrene copolymer (CAS NO: 1309-64-4), and as a fluidity improving agent (antistatic agent) is glyceryl monostea Glyceryl monostearate (CAS NO: 1309-64-4) can be used, and n-octadecyl-3- (4-hydroxy-3,5-di-butylbutyl) propionate as an antioxidant (n-octadecyl-3- (4-hydroxy-3,5-di-t-butyl phenyl) propionate, CAS NO: 2082-79-3) can be used.

The additive is preferably used within 10 parts by weight based on the total weight of PE-RT used in the inner layer.

The outer layer consists of high density polyethylene (HDPE) and a masterbatch.

The high-density polyethylene is a synthetic resin excellent in processability and formability, by forming the outer layer to surround the inner surface of the inner layer with high-density polyethylene can further complement the processability and formability to the general physical properties of PE-RT.

The master batch (pigment) must include carbon black to be able to maintain the anti-aging or long-term durability of the pipe. At this time, the carbon black is preferably included in the total weight of the master batch to be 40% by weight, the total weight of the pipe of the present invention to be about 2 to 3% by weight.

In addition, by using a separate color master batch to distinguish the color of the high-temperature piping, it is possible to check the use, characteristics, etc. by the color of the final pipe obtained. At this time, in the present invention, the pipe color is a master batch of orange color so as to express the entire color of the pipe used for the mast batch for gray and PE-RT raw material of the inner layer.

In order to distinguish it from general pipes, it is intended to be expressed on the outer surface of the pipe in the form of whole or space (2 or 3 lines).

As a coloring agent other than the said carbon black, normal organic and inorganic pigments, such as cadmium mercury red and phthalocyanine green, can be used.

The master batch (based on 40% by weight of carbon content) containing high density polyethylene and carbon black forming the outer layer is preferably used in a weight ratio of 1.5 to 2.0: 1.

The melt index (MI) of the high density polyethylene used in the multilayer tube is 0.12g / 10min, the melt index (MI) of PE-RT is 0.65g / 10min, the melt index represents the fluidity of the synthetic resin, and the PE-RT is Because of high viscosity of melt index and low viscosity, flow does not continue when passing through the extruder, and the polymer flow is cut off, which makes molding difficult. Therefore, when used alone, fluidity is not good. In order to produce a high-density polyethylene of the polyethylene (PE) system as the outer layer to wrap the inner layer and by partially mixing the fluidity improver, it is possible to produce a high-temperature pipe for medium and large diameter during extrusion molding.

As described above, the multilayer tube of the present invention is formed with an outer layer to surround the inner layer surface of PE-RT with high density polyethylene. The inner layer is preferably 80 to 90 parts by weight based on the total weight of the pipe, and the outer layer is formed to be 10 to 20 parts by weight based on the total weight of the pipe. When the weight range of the inner layer and the outer layer is in the above range, the affinity between PE-RT and high density polyethylene is excellent, and the physical properties of each resin are complemented to each other to exhibit maximum heat resistance, workability, and moldability.

In addition, the high-temperature pipe of the multilayer tube is nominal 150, the thickness of the inner layer cross section is 18.2 ~ 20.5mm, the thickness of the outer layer cross section is 2.2 ~ 3.0mm, the overall thickness is 20.4 ~ 23.5mm as the Korea Industrial Standard (KS M 3408-2: water-soluble polyethylene pipe).

In addition, the high temperature pipe of the present invention is characterized in that the single-layer pipe comprising a polyethylene raised temperature (PE-RT), high density polyethylene (HDPE), master batch and additives.

The resin component used in the single-layer pipe is modified by polymer alloying PE-RT and high density polyethylene, and has impact resistance, flexibility, and heat resistance of the existing polyethylene, and at the same time, processability and formability of the high density polyethylene. This is a new resin that is complemented.

The resin component may be produced by melt-extruding PE-RT and high-density polyethylene using an extruder, and in this case, it is preferable to mix at an appropriate ratio to prevent separation between the affinity and kneading with each other.

The PE-RT is preferably used in an amount of 80 to 90 parts by weight based on 100 parts by weight of the resin component used in the single-wall pipe. When the content is within the above range, it is possible to impart excellent impact resistance, flexibility and heat resistance to the pipe, which is better in terms of affinity with high density polyethylene.

It is preferable that the said high density polyethylene is used in 10-20 weight part with respect to 100 weight part of resin components used for a single-wall pipe. When the content is within the above range, it is possible to impart excellent processability and formability to the pipe, it is better to prevent separation when kneading with PE-RT.

In addition, the master batch may use the same purpose and components as the master batch used in the above-described multilayer tube, and a detailed description thereof will be omitted.

The master batch is used in 5 to 6 parts by weight with respect to 100 parts by weight of the resin component is excellent in the aging, crack prevention effect, it is better to see the maximum effect according to the amount used.

In addition, the pipe of the single-layer pipe made of the above components may further include additives such as impact modifiers, fluidity improvers, antioxidants, etc. in an amount of 4 to 6 parts by weight based on 100 parts by weight of the resin component in order to increase heat resistance and reforming performance.

Since the additive is the same as the component used in the above-described multilayer tube, a detailed description thereof will be omitted here.

Single-wall tube high temperature pipe of the present invention made of the above components can be produced so that the total thickness is 20.4 ~ 23.5mm in the case of the nominal 150.

The high temperature pipe in the form of a multi-layer pipe or a single-layer pipe manufactured as described above has excellent thermal conductivity due to its smooth surface, and is easy to handle due to its light weight as a plastic product. This strong and easy pipe connection work such as heat fusion, heating and cooling pipe in glass greenhouse for special crop cultivation, heating and cooling pipe using geothermal and solar heat among new renewable energy, heat pump pipe in machine room, sea water It can be used as a pipe, such as cooling water discharge pipe for power plants. In addition, the high temperature pipe of the present invention can be manufactured in a large diameter of 100 ~ 200mm and more with excellent workability and formability.

Hereinafter, the high temperature pipe of the present invention will be described in detail with reference to the accompanying drawings. The configuration shown in this drawing is only one of the most preferred embodiments of the present invention and does not face all of the technical idea of the present invention, there may be various equivalents and modifications that can replace them at the time of the present application Should be understood.

1 is a cross-sectional view of a hot pipe of a multi-layer tube according to an embodiment of the present invention, Figure 2 is a cross-sectional view of a hot pipe of a single-wall tube according to another embodiment of the present invention.

Referring to Figure 1, the high-temperature pipe (1) of the multi-layer pipe manufactured according to an embodiment of the present invention is an inner layer 10 made of PE-RT and an outer layer 20 made of high density polyethylene and masterbatch It is composed.

The inner layer 10 is formed so that the cross-sectional thickness is 18.2 ~ 20.50mm in the case of No. 150 using PE-RT as the main raw material, the cross-sectional thickness using high density polyethylene and master batch to cover the outer surface of the inner layer 10 The outer layer which is 2.2-3.0 mm is formed.

Since the detailed description of the inner layer 10 and the outer layer 20 is the same as described above, a detailed description thereof will be omitted.

Referring to Figure 2, the hot pipe (2) of the single-layer pipe according to another embodiment of the present invention is manufactured with PE-RT, high density polyethylene and masterbatch and additives as a main component.

The single-layer pipe high temperature pipe layer 30 using the components as described above was manufactured so that the total thickness is 20.4 ~ 23.5 mm in the case of the nominal 150, and the specific name for the single-wall tube high temperature pipe 30 is the same as described above. , The detailed description is omitted here.

Hereinafter, the present invention will be described in more detail with reference to examples. These embodiments are for purposes of illustration only and are not intended to limit the scope of protection of the present invention.

Example 1

4 weights of impact modifier (CAS NO: 1309-64-4), fluidity improver (CAS NO: 1309-64-4) and antioxidant (CAS NO: 2082-79-3) as additives to 80 parts by weight of PE-RT resin In the case of No. 150, the inner layer pipe having a cross section thickness of 18.2 mm was manufactured by adding parts.

20 parts by weight of high density polyethylene (HDPE), 1.25 parts by weight of carbon black (40% by weight), and 0.01 parts by weight of cadmium red, which is an orange colorant, were added to the surface of the inner layer pipe. The outer tube was manufactured to produce a hot pipe in the form of a multilayer tube having a pipe diameter of 150 mm.

Example 2

80 parts by weight of PE-RT resin and 20 parts by weight of high-density polystyrene (HDPE) are mixed and melted and extruded using an extruder to 100 parts by weight of the resin component, and 6 parts by weight of carbon black (40 wt%) is added in a mast batch and impacted. 5 parts by weight of a reinforcing agent (CAS NO: 1309-64-4), a flow improving agent (CAS NO: 1309-64-4) and an antioxidant (CAS NO: 2082-79-3) was added, and the total thickness was 20.4-23.5 mm, A high temperature pipe in the form of a single layer pipe having a pipe diameter of 150 mm was manufactured.

Comparative Example 1

Conventional high density polyethylene (HDPE) pipes have been used.

Comparative Example 2

Conventionally high temperature polyethylene (PE-RT) pipes have been used.

The physical properties shown in Table 1 below were measured using the pipes of Example 1 and Comparative Examples 1 and 2, and the results are shown in Table 1 below.

In addition, the internal pressure test and the highest pressure test under high temperature for the pipes of Examples 1 and 2 and Comparative Examples 1 and 2 were measured by the methods of Tables 2 and 3, and the results are shown in Table 4 below.

As shown in Tables 2 to 4, the high temperature pipes of Examples 1 and 2 prepared according to the present invention showed excellent heat resistance even at a temperature of 70 to 90 ° C., and also showed excellent workability.

Further, using the pipes of Examples 1 and 2 and Comparative Examples 1 and 2, heat resistance at high temperature 70 ° C, pressure resistance at high temperature (70 ° C) and low temperature (-20 ° C), workability and moldability were measured. The results are shown in Table 5 below.

As shown in Table 5, the high-temperature pipes of Examples 1 and 2 manufactured in the form of a polymer alloy or a multilayer tube using PE-RT and high-density polyethylene (HDPE) as the main ingredient resin according to the present invention. It can be seen that the heat resistance at high temperature 70 ℃, high temperature 70 ℃ and low pressure -20 ℃ all excellent, in addition to the physical properties such as impact strength, molding shrinkage, bending tendency.

In addition, the PE-RT pipe of Comparative Example 2 was not good workability and formability could be manufactured only in small diameter, but the high temperature pipes of Examples 1 and 2 according to the present invention is excellent in workability and formability diameter It was confirmed that the fabrication was possible even with a large diameter of 100 mm or more.

In addition, it can be seen that the high temperature pipes of Examples 1 and 2 according to the present invention can easily maintain the watertightness of the connection part by easy pipe connection (butt fusion type) by electrofusion.

Through such a result, the high temperature pipe according to the present invention is a pipe for heating and cooling in a glass greenhouse for special crop cultivation, a heating and cooling pipe using geothermal and solar heat among renewable energy, a pipe for a heat pump of a machine room, seawater It could be predicted that it could be used as large-diameter pipe such as cooling water discharge pipe for power plant.

Although the present invention has been described as the preferred embodiment mentioned above, it is possible to make various modifications or variations without departing from the spirit and scope of the invention. The appended claims also cover such modifications and variations as fall within the spirit of the invention.

1 is a cross-sectional view of a multi-layer tube high temperature pipe according to an embodiment of the present invention.

2 is a cross-sectional view of a single-wall tube high temperature pipe according to another embodiment of the present invention.

Explanation of symbols on the main parts of the drawings

 1: multi-layer high temperature pipe 2: single layer high temperature pipe

10: inner layer of high temperature pipe of multilayer tube 20: outer layer of high temperature pipe of multilayer tube

30: single layer high temperature pipe layer

Claims (7)

a) an inner layer comprising polyethylene raised temperature (PE-RT); And b) an outer layer formed to surround the inner layer and comprising a high density polyethylene (HDPE) and a masterbatch; High temperature pipe comprising a. The method of claim 1, The pipe is a high temperature pipe, characterized in that formed of 80 to 90 parts by weight of the inner layer and 10 to 20 parts by weight of the outer layer relative to the total weight of the pipe. The method of claim 1, The inner layer further comprises any one or more additives selected from impact modifiers, flow improvers and antioxidants. The method of claim 1, The high density polyethylene and the masterbatch (carbon content) is a high temperature pipe, characterized in that used in the weight ratio of 1.5 ~ 2.0: 1. A high temperature pipe comprising a polyethylene raised temperature (PE-RT), a high density polyethylene (HDPE), a masterbatch and an additive. The method of claim 5, The PE-RT is used in 80 to 90 parts by weight based on 100 parts by weight of the resin component used in the pipe, the high-density polyethylene is used in 10 to 20 parts by weight, the master batch is used at 5 to 6 parts by weight pipe. The method of claim 5, The additive is any one or more components selected from impact modifiers, fluidity improvers and antioxidants, high temperature pipe, characterized in that used in 4 to 6 parts by weight based on 100 parts by weight of the resin component.

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