KR20230033933A - Resin composition for guardrail end terminal and surface coating composition comprising the same - Google Patents

Abstract

The present invention relates to a resin composition for manufacturing guardrail end terminals. The resin composition comprises: 100 parts by weight of at least one resin selected from polyethylene (PE), polypropylene (PP), polycarbonate (PC), polyvinyl chloride (PVC), and acrylonitrile-butadiene-styrene (ABS); 0.5 to 2 parts by weight of zinc peroxide; and 5 to 10 parts by weight of any one stabilizer selected from bis[2-(methacryloyloxy)ethyl]phosphate (BMEP), o-phosphorylethanolamine (o-PEA), and sodium citrate. The purpose is to provide a resin composition that can improve durability and impact resistance.

Description

A resin composition for guardrail end terminals and a surface coating composition for guardrail end terminals comprising the resin composition.

The present invention relates to a resin composition for manufacturing a road guardrail end terminal and an end terminal surface coating composition comprising the resin composition, wherein an end terminal installed at the end of a road guardrail structure is formed of a resin composition, while It relates to a resin composition having sufficient strength and durability.

A guardrail is a road facility installed along a roadside for the purpose of marking the boundary of a road and preventing vehicles from departing, and is generally made of a metal material. The guardrail needs to have high impact strength to prevent the vehicle from being separated when the vehicle collides, while at the same time it is required to have characteristics capable of absorbing impact applied to the vehicle and the guardrail to protect the driver and passengers.

The applicant developed resin guardrails made of plastic to replace the existing metal guardrails, and Korean Patent Registration Nos. 10-1835000, 10-1738549, 10-1771134, 10-1763292, 10- 1799852 and the like have disclosed related technologies. This is a technology for improving the structural stability of guardrails, and through this, the durability and impact resistance of resin guardrails can be improved to replace metal guardrails.

In addition, there is a limit to improving durability or impact resistance only by improving the structure of the resin guardrail, and recently, through Korean Patent Registration No. 10-2024543, polyvinyl chloride (PVC) and acrylonitrile-butadiene-styrene We are developing a product in the direction of improving the material of the resin guardrail by developing a technology using a resin composition containing (ABS).

As shown in FIG. 1, the structure for installing the guardrail on the roadside is to fix the resin guardrail in the horizontal direction continuously using brackets on the guardrail support vertically embedded in the road surface, or the guardrail without a separate bracket It is constructed by being directly coupled to the holding post and fixed. At this time, an end terminal is coupled to an end of the guardrail to form an end portion. Like the main body of the guardrail, the end terminal requires high durability and impact resistance.

Recently, in order to realize the visual effect of the guardrail, the demand for wood color guardrails having a wood-textured surface is increasing, and accordingly, the applicant is developing a guardrail using synthetic wood. The synthetic wood is molded by mixing plastic and wood powder, and can exhibit the same texture as wood, so it is a material suitable for realizing visual effects. Therefore, it is used for interior and exterior materials for construction, flooring, etc., and is also applied to guardrails in India.

However, when using the synthetic wood, there is a problem in that it is difficult to obtain sufficient durability and impact resistance when applied to a guardrail installed on a road because the strength is lowered due to the combination of plastic and wood flour, and simply expressing the texture of wood In the case of mixing plastic and wood flour as a material for the guardrail, an increase in manufacturing cost may also be a problem. In particular, since the end terminal part has a curvature, surface damage can easily occur, so it needs to be improved.

The present invention has been made in view of the prior art as described above, and an object of the present invention is to provide a resin composition capable of improving durability and impact resistance of road guardrail end terminals made of synthetic resin.

In addition, when extruding the end terminal to realize wood color on the surface of the end terminal, a surface coating composition composed of wood flour and the resin composition is double-extruded to realize wood color on the surface of the guardrail end terminal Surface coating that can implement wood color It is an object thereof to provide a composition.

The resin composition of the present invention to solve the above problems is for manufacturing a guardrail end terminal, the resin composition is polyethylene (PE), polypropylene (PP), polycarbonate (PC), polyvinyl chloride (PVC) ) And 100 parts by weight of at least one resin selected from acrylonitrile-butadiene-styrene (ABS), any one selected from caprylic acid, pelargonic acid or capric acid 3 to 5 parts by weight of a carboxylic acid, 0.5 to 2 parts by weight of zinc peroxide, and bis[2-(methacryloyloxy)ethyl] phosphate (BMEP), o-phosphorylethanolamine (o-PEA) , 5 to 10 parts by weight of any one stabilizer selected from sodium citrate.

The resin composition may additionally include any one or more of a UV absorber, a photocatalyst, and a light stabilizer.

In addition, the coating composition for other guardrail end terminals in the present invention is characterized in that it consists of 60 to 80% by weight of the resin composition and 20 to 40% by weight of wood flour.

By using the resin composition according to the present invention, road guardrail end terminals made of conventional metal materials can be manufactured with synthetic resin, and sufficient durability and impact resistance of the manufactured end terminals can be secured.

In addition, when the end terminal is extruded to implement a wood color on the surface of the end terminal, a surface coating composition composed of wood flour and the resin composition may be double-extruded to implement a wood color on the surface of the guardrail end terminal.

1 is a conceptual diagram showing the installation state of a road guardrail structure.
2 is a conceptual diagram illustrating a state in which an end terminal is coupled to a road guardrail structure.
Figure 3 is a cross-sectional view showing the cross-sectional structure of the guardrail end terminal of the present invention.
4 is a photograph of a prototype guardrail end terminal of the present invention, and is an exemplary view showing a roadside guardrail end terminal (a) and a median barrier end terminal (b).

Hereinafter, the present invention will be described in more detail. Terms or words used in this specification and claims should not be construed as being limited to ordinary or dictionary meanings, and the inventor may appropriately define the concept of terms in order to explain his or her invention in the best way. It should be interpreted as a meaning and concept consistent with the technical idea of the present invention based on the principle that there is.

The resin composition according to the present invention is for manufacturing a guardrail end terminal, and the resin composition includes polyethylene (PE), polypropylene (PP), polycarbonate (PC), polyvinyl chloride (PVC) and acrylonitrile-butadiene - 100 parts by weight of at least one resin selected from styrene (ABS), 3 to 5 parts by weight of any one carboxylic acid selected from caprylic acid, pelargonic acid or capric acid parts by weight, 0.5 to 2 parts by weight of zinc peroxide, and any selected from bis[2-(methacryloyloxy)ethyl]phosphate (BMEP), o-phosphorylethanolamine (o-PEA), and sodium citrate It is characterized by consisting of 5 to 10 parts by weight of one stabilizer.

An end terminal may be manufactured by extrusion molding using the resin composition. As shown in FIG. 2, the end terminal includes an inner wall, an outer wall disposed to face the inner wall, and a plurality of ribs connecting a space between the inner wall and the outer wall. It can be configured to include.

The structure of the guardrail end terminal is the same as that of the resin guardrail disclosed by the applicant in Korean Patent Registration No. 10-2024543, which is formed by constructing the resin guardrail to form a guardrail structure, and at the end of the present invention In order to complete the guardrail structure by combining end terminals, it has the same cross-sectional structure as the resin guardrail body.

As shown in FIG. 3, the guardrail end terminal is composed of an inner wall, an outer wall, and a rib. In addition, as shown in Figure 2, it is installed at the end where the guardrail is installed, and the inner wall is installed by providing a fixing surface to the support and fastening it. In addition, the outer wall is disposed to face the inner wall to provide a contact surface for external impact, and the ribs are formed in plurality to connect a space between the inner wall and the outer wall to absorb shock.

In addition, as shown in FIG. 4, since the shape of the guardrail end terminal can be different depending on the installation location such as for roadside use or median separator, the rib also considers structural stability according to the shape of the guardrail end terminal. Thus, it may have a 'Y' shape, or may be configured in various shapes such as 'I', 'V', and 'X' shapes.

The guardrail end terminal is manufactured using a synthetic resin instead of a metal material like a known resin guardrail. In the present invention, as a resin composition for constituting the guardrail end terminal, 100 parts by weight of synthetic resin, 3 to 5 carboxylic acids It is technically characterized by using a resin composition composed of 0.5 to 2 parts by weight of zinc peroxide, and 5 to 10 parts by weight of a stabilizer.

As the synthetic resin, one or a mixture thereof selected from polyethylene (PE), polypropylene (PP), polycarbonate (PC), polyvinyl chloride (PVC), and acrylonitrile-butadiene-styrene (ABS) may be used. For example, polyvinyl chloride (PVC) and acrylonitrile-butadiene-styrene (ABS) disclosed by the applicant in Korean Patent Registration No. 10-2024543 may be used as synthetic resins.

In addition, as the synthetic resin, not only a new plastic material but also a mixture of waste plastics may be used. Through this, waste plastic can be recycled to manufacture guardrail end terminals. In addition, when using waste plastic, it may be blended and used in the range of 60 to 80% by weight of waste plastic and 20 to 40% by weight of new plastic material.

In order to manufacture guardrail end terminals using various types of synthetic resins, a means to improve moldability and durability of synthetic resins is required. In particular, in the case of waste plastics, the compatibility of the resin itself tends to deteriorate Therefore, it is necessary to optimize the composition of the resin composition to improve the bonding strength of the resin in the molding process.

To this end, a binder composed of 3 to 5 parts by weight of carboxylic acid, 0.5 to 2 parts by weight of zinc peroxide, and 5 to 10 parts by weight of a stabilizer is mixed with the synthetic resin to form a resin composition. When the resin composition is used, even if it contains various plastics or waste plastics, a smooth curing reaction can be caused in the molding process of the guardrail end terminal, so that the guardrail end terminal having excellent durability and impact resistance can be manufactured.

In Korean Patent Registration Publication No. 10-2024543, the applicant is a resin composition for manufacturing a resin guardrail body, in which a PVC compound and an ABS compound are mixed in a weight ratio of 50:50 to 90:10, based on 100 parts by weight of a resin mixture acrylic acid and hydrogen peroxide , lithium nitrate trihydrate, and 1 to 10 parts by weight of microcapsules containing acrylonitrile are mixed to improve the bonding force between resins in the molding process of the guardrail, thereby improving the durability and impact resistance of the prepared resin guardrail. When the acid component, the base component, the metal catalyst, and the stabilizer contained in the resin composition are properly mixed, the bonding strength of the resin is improved in the molding process, thereby improving the durability and impact resistance of the molded article.

In the present invention, by using the principle of the applicant's developed technology, a binder composed of acid, base, and metal catalyst is used to improve the bonding strength of the synthetic resin constituting the guardrail end terminal during molding processing to form a surface with high strength and excellent impact resistance will do

The carboxylic acid is used as an acid component. Conventionally, a strong acid is used to promote the reaction in the molding process, but in the present invention, a carboxylic acid having 8 to 10 carbon atoms in an alkyl group is used as the carboxylic acid, there is. That is, caprylic acid, pelargonic acid, or capric acid may be used as the carboxylic acid, and the carboxylic acid has a pKa of 4.89, 4.96, and 4.9, respectively, and is a relatively weak acid. that corresponds to It is known that when the acidity is weak, sufficient bonding strength cannot be exhibited even when mixed with a base. However, in the present invention, sufficient moldability of waste plastic can be obtained even when a weak acid is contained by appropriately adjusting the pressure and molding time during pressure molding. In addition, the carboxylic acid is used in the range of 3 to 5 parts by weight, but if the content of the carboxylic acid is too small or too large, moldability is lowered and the strength of the molded article is insufficient.

In addition, the zinc peroxide is used to supply metal ions, which are ionized in an aqueous solution to form peroxide salts and zinc ions. In addition, the zinc peroxide has a pKa of about 7, corresponding to a weak base. When mixed with the carboxylic acid and pressure is applied in the molding process, the zinc peroxide reacts and promotes the bonding reaction of the polymer.

The zinc peroxide is preferably contained in the range of 0.5 to 2 parts by weight. Outside of the above range, the acid-base reaction was insufficient, so that strong bonding strength could not be obtained during the manufacture of the molded article, and thus the strength of the molded article was insufficient.

In addition, zinc peroxide and hydrogen peroxide may be mixed. In this case, it is preferable to add 0.1 to 0.5 parts by weight of hydrogen peroxide to 0.5 to 2 parts by weight of zinc peroxide. Through experiments with various formulations, it was found that the acid-base reaction that occurs during the molding process can be promoted by mixing a small amount of hydrogen peroxide.

In addition, the stabilizer is added to stabilize the peroxide such as zinc peroxide or hydrogen peroxide so that the resin does not harden until the resin composition is molded. As a stabilizer capable of stabilizing the zinc peroxide, any one of bis[2-(methacryloyloxy)ethyl]phosphate (BMEP), o-phosphorylethanolamine (o-PEA), and sodium citrate may be used. . It is known that the stabilizer is adsorbed on the surface of the nanoparticled peroxide to stabilize it so that it does not dissociate.

Therefore, by mixing the stabilizer, acid-base reaction in the resin composition is stabilized so that the composition can be formed. The stabilizer is preferably used in the range of 5 to 10 parts by weight, which is introduced in an amount determined stoichiometrically to sufficiently cover zinc peroxide according to the content of peroxide.

The guardrail end terminal may be manufactured through a conventional extrusion or injection molding process, and may be manufactured by heating and melting the resin composition at 180 to 220° C. and then using an injection molding machine or an extruder.

In addition, it was found that a temperature of 120° C. or more and a pressure of 30 kgf/cm 2 or more are required to react the acid and base components contained in the resin composition. Since the above temperature and pressure can be realized in a conventional double extrusion process, the bonding strength during the molding process It is believed that improvement can be achieved. In addition, since the self-crosslinking of the resin occurs during the cooling stabilization process after the molding process is finished, it was found that sufficient bonding force can be obtained regardless of the type of resin or whether waste plastic or new material is used.

In addition, when molding the guardrail end terminal, a surface coating composition composed of 60 to 80% by weight of a resin composition and 20 to 40% by weight of wood flour may be laminated on the surface of the outer wall to achieve a wood color. That is, the guardrail end terminal is formed to realize the texture of wood by the surface coating formed on the outer surface of the guardrail end terminal.

To this end, the same resin composition as the resin composition for forming the guardrail end terminal may be used as the resin composition, and even if wood flour is mixed with the resin composition, sufficient bonding strength can be obtained, so that a synthetic wood layer is formed on the surface through an extrusion or injection molding process. can be layered. For example, when extruding a guardrail end terminal, a synthetic wood layer can be easily formed on the surface by extruding with double extrusion. In addition, the synthetic wood layer contains wood flour in the range of 20 to 40% by weight, and even if it contains a small amount of wood powder, it is distributed only on the outer surface of the guardrail end terminal, so that wood color with sufficient wood texture can be implemented.

In addition, the synthetic wood layer can be formed in a wide range of thickness from 50㎛ to 10㎜. Since the synthetic wood layer is intended to implement visual effects, it is okay to have a thin thickness, but it may be formed to a thickness of several mm in consideration of problems such as damage to the synthetic wood layer over time.

In addition, functionality may be imparted to the surface of the guardrail end terminal by additionally including any one or more of a UV absorber, a photocatalyst, and a light stabilizer in the resin composition. In particular, it is helpful to improve product quality by adding additives to prevent deterioration or surface contamination by UV rays due to the characteristics of guardrail end terminals installed on roadsides.

As the ultraviolet absorber, 2,2',4,4'-tetrahydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzo Phenone, 2-hydroxy-4-n-octyloxybenzophenone, 2-(5-chloro-2H-benzotriazol-2-yl)-6-(1,1-dimethylethyl)-4-methyl- Either phenol can be used.

In addition, titanium dioxide (TiO ₂ ) and zinc oxide (ZnO) may be used as the photocatalyst.

In addition, the light stabilizer is poly[[6-[6-[(1,1,3,3-tetramethylbutyl)amino]-1,3,5-triazine-2,4-diyl][2, 2,6,6-tetramethyl-4-piperidyl]imino], (1-octyloxy-2,2,6,6-tetramethyl-4-piperidinyl)sebacic acid, bis(1,2 ,2,6,6-pentamethyl-4-piperidyl)sebacic acid may be used.

It is preferable that the total amount of the ultraviolet absorber, photocatalyst, and light stabilizer added is less than 5 parts by weight. If the addition amount is too large outside the above range, the moldability of the resin composition is deteriorated.

In order to confirm whether the physical properties of the guardrail end terminal according to the present invention are lower than those of the conventional guardrail end terminal, a test evaluation was conducted as follows. Since the resin composition hardens in the molding process to form a structure, it is difficult to test and evaluate the resin composition itself, so the effect was evaluated by directly evaluating the finished product after molding the end terminal.

It was compared with the steel guardrail end terminal currently constructed on the road. As a resin composition for manufacturing a guardrail end terminal, guardrail end terminal test specimen 1 using a resin composition mixed in a ratio of 4 parts by weight of capric acid, 1 part by weight of zinc peroxide, and 6 parts by weight of sodium citrate with respect to 100 parts by weight of PVC. was manufactured. In addition, using a resin composition in which 4 parts by weight of capric acid, 1 part by weight of zinc peroxide, and 6 parts by weight of sodium citrate were mixed with respect to 100 parts by weight of a synthetic resin in which waste plastic PVC and new PVC were mixed in a weight ratio of 7:3, Another guardrail end terminal specimen 2 was prepared. In addition, a guardrail end terminal specimen 3 was prepared using a resin composition mixed with 100 parts by weight of PVC, 4 parts by weight of capric acid, 0.8 parts by weight of zinc peroxide, 0.2 parts by weight of hydrogen peroxide, and 6 parts by weight of sodium citrate.

For the guardrail end terminal, an SB2 grade crash test was conducted according to the 'vehicle protection safety facility actual crash test' conducted by the 'Korea Transportation Safety Authority' (height: 750mm, minimum installation length 30m, horizontal bearing capacity of the prop 4.49 tonf). ).

The strength performance evaluation crash test was conducted under the conditions of a test vehicle weight of 8,030 kg, impact speed of 65.5 km/h, impact angle of 15°, and impact of 89 kJ. /h, the collision angle was carried out under the conditions of 20 °.

As a result, it was found that both the steel guardrail end terminal constructed on the road and the protective fence performance evaluation and the protective fence impact test conducted on specimens 1 to 3 satisfied the SB2 (Korean standard test) grade. These results suggest that the guardrail end terminal according to the present invention exhibits sufficient durability and impact resistance.

The rights of the present invention are defined by what is described in the claims, not limited to the embodiments described above, and that those skilled in the art can make various modifications and adaptations within the scope of rights described in the claims. It is self-evident.

Claims (3)

As a resin composition for manufacturing a guardrail end terminal,
The resin composition includes 100 parts by weight of at least one resin selected from polyethylene (PE), polypropylene (PP), polycarbonate (PC), polyvinyl chloride (PVC) and acrylonitrile-butadiene-styrene (ABS), caprylic 3 to 5 parts by weight of any one carboxylic acid selected from caprylic acid, pelargonic acid or capric acid, 0.5 to 2 parts by weight of zinc peroxide, and bis[2-( A resin composition comprising 5 to 10 parts by weight of any one stabilizer selected from methacryloyloxy)ethyl]phosphate (BMEP), o-phosphorylethanolamine (o-PEA), and sodium citrate.
The method of claim 1,
The resin composition further comprises any one or more of a UV absorber, a photocatalyst, and a light stabilizer.
A coating composition for guardrail end terminals comprising 60 to 80% by weight of the resin composition according to claim 1 and 20 to 40% by weight of wood flour.

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