KR900007763B1 - Polyethylene resin concrete compositions - Google Patents

Abstract

The polyethylene resin concrete compsn is produced by the stages of preparing 12 wt.% high density and 14-30 wt.% low density polyethylene respectively by separating, washing and drying, adding 0.5 wt.% asbestos or 0.1-0.3 wt.% oxidized steel as reinforcing agent, adding 0.05-0.2 wt.% antimony or paraffin chlorid as oxidation inhibitor, carbon black as ultraviolet shielding agent, adding and heatmixing 60-80 wt.% dried aggregate and pressmoulding, rolling, cooling and demoulding. The compsn. has a good tensile and bending strength, a low coefficient of heat expansion, a good chemical resistance.

Description

Polyethylene Blended Resin Concrete Composition

The accompanying drawings are process schematics showing the manufacturing process of the present invention.

The present invention relates to a polyethylene-containing resin concrete composition, and more specifically, by mixing a high density polyethylene, low density polyethylene and aggregate and other additives in a proportion, strength and other properties can be remarkably improved as compared with general cement concrete structures. It relates to a resin concrete composition.

In general, polyethylene resins have higher melt viscosity as their molecular weight increases, and are easily regenerated and molded as resins having patented thermal and chemically superior properties.

Therefore, these fields of use are gradually spreading for various purposes with the development of the degree of blending ratio and use.

The present invention is one of the fields of application, the high-strength, and to provide a compounding resin concrete composition that can be effectively used in construction or other civil engineering fields where the impact resistance, chemical resistance and electrical insulation, water tightness, etc. are remarkably required have. In the existing construction and civil engineering fields, concrete structures using conventional cement are generally used. These include risk factors for structural safety due to erosion by chemical reactions or the effects of seawater. In the construction of major facilities or vulnerable districts, which require rapid speed, the construction of cement concrete requires considerable time, so many technical problems have been pointed out. In addition, they are expanding their required cross-sections more than necessary to secure the attachment stress with subsidiary materials including reinforcing bars, and the problems of structural management, repair and reinforcement after construction are also emerging as major technical tasks. Was.

Such a concrete structure has a relatively large resistance to compressive stress acting in the axial direction of the structure, while the bending and tensile strength due to long-term load or torsion are very small compared to the compressive strength, and the tensile strength is also minute, so the tensile stress is small. Inevitably, the cracks are generated, resulting in an unstable structure. Therefore, as a way to improve the problems of the concrete structure using the above-mentioned cement, the resin and aggregate were mixed to produce synthetic resin concrete. Although many efforts and researches are being made on their manufacturing, no effective method has been suggested. In addition, most of them are made of resin concrete by mixing aggregates with polyester resins, polyurethane resins, and epoxy resins. The resins generally used here are considerably more expensive than the polyethylene resins used in the present invention. It is impossible to produce economical products, and due to the problem of being eroded by academic materials such as acid and alkali, the durability and economic feasibility are extremely slim.

Accordingly, the present inventors have repeatedly conducted repeated experiments for the purpose of improving the above-mentioned defects. As a result, by using polyethylene resins widely used in all industries, the mechanical strength and chemical resistance are improved. Of course, it has been found that the above problems can be solved smoothly. Especially 0 were mixed with 941 to 0.970g / high-density polyethylene, and 0.910 to the predetermined low-density polyethylene having a density distribution ratio of 0.940g / cm ³ having a density distribution in cm ³ complementary mutual trade-offs, and blending, additive and sand, gravel By mixing aggregates, etc., it was possible to obtain a high-density, high-strength composition that can provide a cost reduction effect as well as mechanical strength and chemical resistance improvement compared to existing resin concrete compositions.

In addition, by adding a certain amount of additives such as vinyl chloride and salicylic acid ester, benzene acid ester, antimony oxide, tetrabromopusmutal acid, and carbon black to the composition, it is possible to effectively prevent deformation due to heat and self-righteousness, which is a weak point of polyethylene resin. I could see. In the present invention, by using the polyethylene used as the main raw material to recover and recycle the waste polyethylene occupying a large number of industrial waste, it is very efficient as a solution to the aspects of resource utilization and pollution problems, and the production cost is manufactured at a lower price The dual effect could be achieved.

In the present invention, by combining additives and reinforcing agents in polyethylene, a high-molecular and low-density polyethylene, which is a homopolymer having a single repeating structure, the thermal, chemical, and physical properties of the polyethylene are remarkably improved. In addition, as an additive, an antioxidant such as vinyl chloride, salicylic acid ester, benzene acid ester and antimony oxide, tetrabromomus phthalic acid, and anti-ultraviolet ray blocking agent, that is, carbon black, are mixed at a predetermined ratio, and heat, ultraviolet rays, and antioxidant effects are You can increase it. The molecule of ethylene used in the present invention is a single bond as C ₂ H ₄ , several are linked to constitute a polymer. In other words, crystalline high-density polyethylene with very low branching structure and low-density polyethylene forming a multi-layered structure, that is, atactic, isotactic, and syndiotactic structures, are largely classified according to the branching structure. In addition, the polymer having low atactic and syndiotactic structure has low mechanical strength, so that chaintwist is not easily formed. However, the isotactic polymer has a high density and high mechanical strength, so it is possible to improve the strength and transparency of the polymer by using catalysts such as AlCl ₃ and TiCl ₄ to improve the mechanical strength and transparency. A composition can be obtained.

That is, the use of a catalyst reduces the branching of polyethylene, improves crystallinity, and improves mechanical strength. Therefore, a high density polyethylene having a density distribution of 0.941 to 0 970 g / cm ³ is polymerized with linear polyethylene to be produced by a medium-low pressure method, and a low density polyethylene having a density distribution of 0.910 to 0 940 g / cm ³ has many branches. Since the polymer is polymerized, it is produced by a high pressure method. In addition, when the density distribution hayeoteul slowly cooled to 0 950g / cm ³ of the density distribution of the polyethylene is set to indicate the density of 0.920g / cm ³ when hayeoteul quenching it to be 0 960g / cm ^3. Polyethylene having the above properties has a relatively high shrinkage, so that the shrinkage is 3-4% by volume in the injection direction and 1-5-2% by volume in the perpendicular direction. to be.

The present invention constitutes a resin concrete composition by combining high density polyethylene and low density polyethylene, sand, pigments, and reinforcing agents and other additives, wherein the high density polyethylene or the low density polyethylene has a basic composition of C ₂ H ₄ , By adding sand to the low density compounding resin, the warpage and the increase of the overall strength and density are brought into high density and high strength state. In the resin concrete composition, the high density polyethylene and the low density polyethylene have a stable folded chain structure together with various fillers in the energy melted state in general, so that the degree of mixing is more stable.

In addition, the polyethylene high polymer resin concrete is not formed of pure resin but is reinforced with gravel, sand, etc., and is formed in a high density state by applying a mechanical load.

In other words, even if only low-density polyethylene is produced, a composition having a high density density distribution can be obtained by mixing with an additive, which is itself catalyzed by additives such as Fe ₂ O ₃ , TiCl ₄ , and AlCl ₃ . It will be denser.

The present invention will be described in detail for each manufacturing process as follows. Two polyethylene resins of different densities, specifically, 5-12 wt% of high density polyethylene having a density of about 0.941 to 0.970 g / cm ³ and 14-30 wt% of low density polyethylene having a density of about 0.910 to 0.940 g / cm ³ , respectively, are washed. It is melted at 110 ~ 140 ℃ strength through the process of dehydration and drying, and melted at 110 ~ 140 ℃ strength of high density polyethylene, especially at melting point 105 ~ 110 ℃ of low density polyethylene, but it is 190 to have melt fluidity. It has a desirable fluidity at about 210 ℃. It takes a lot of time and effort to melt the polyethylene uniformly, and it was found that the water content of the resin as a problem factor of the melting had a great influence, and that the water content of the most effective resin was less than 0.1% by weight. It became. Therefore, the surface of the polyethylene resin is washed with water, impurities are removed, dehydrated and dried to have a water content of 0.1 wt% or less.

Thus dried polyethylene resins of different densities are added to the melter together with other participating agents, such as antioxidants and sunscreens, and mixed under a temperature of 190 to 250 ° C., more preferably 220 to 250 ° C. Although the blending ratio of polyethylene varies slightly depending on the use of the composition, the ratio of 20-30 wt% of high density polyethylene is most preferable with respect to 70 to 80 wt% of low density polyethylene, and in particular, the blending amount of low density polyethylene is Because of the close relationship it is virtually difficult to reduce the mix. That is, high density polyethylene is generally used for the purpose of strength reinforcement, and low density polyethylene is used for reinforcing tensile strength, and the effective strength can be exerted by their mutually suitable blending ratio. At this time, as additives to supplement the fragility of the resin, pigments, such as reinforcing agents, antioxidants and sunscreens are added at a certain ratio, and asbestos, iron oxides are mainly used as reinforcing agents. The mixing ratio thereof is preferably 0.1 to 0.3% of asbestos 0 to 0.5% iron oxide relative to the total weight.

As the antioxidant, paraffin chloride and antimony oxide are preferably added in an amount of 0.1 to 0.3%, more preferably in the same weight of 0.1 to 0.2%, and the sunscreen is preferably added in an amount of 0.3 to 0.5% of carbon black.

The mixed resin can provide a composition suitable for the required strength by blending aggregates, such as sand or gravel prior to extrusion, in which the moisture content and the particle size of the aggregate acts as an important factor in order to be uniformly blended in the mixed resin. do. Therefore, the particle size distribution of aggregates is calculated by considering the vertical load, wind load, and earthquake due to dead and live loads. In case of no root: It is preferable to select and use the material in accordance with the provisions of Article 178, Precate: Article 13). It is effective to maintain it.

In addition, the mixing ratio of these aggregates may also be varied depending on the use, but may be 60 to 80% by weight or less, specifically, 30 to 45% by weight of gravel and 30 to 45% by weight of sand or 60 to 80% by weight of sand. It is possible to obtain a composition of high strength and high density which is further reinforced. Hereinafter, the present invention will be described by way of examples.

Example 1

14.2% by weight of low density polyethylene (LDPE) and 5.0% by weight of high density polyethylene (HDPE) having different density distributions were washed, dehydrated and dried to maintain a water content of 0.1% or less, and as an additive, 0.1% by weight of paraffin chloride and oxidation 0.1% by weight of antimony, 5% by weight of asbestos, 0.2% by weight of iron oxide, and 0.4% by weight of carbon black were melted in a melter at a temperature of 190 to 250 ° C, and then 30% by weight of gravel and 45% by weight of sand were added again. Aggregate with a water content of 0.1% or less according to the particle size distribution of the general concrete standard specification was mixed and heated, and extruded, rolled, molded, compressed, cooled, and demolded at an extrusion pressure of 33 to 38 kg / cm ³ . The results obtained therefrom are shown in Table 1.

Example 2

In Example 1, LDPE was 17.2 wt% and HDPE was 7.0 wt%, except that asbestos was removed from the additives. The compounding weight% of each component is shown in Table 1, and the results obtained therefrom are shown in Table 2.

Example 3

In Example 1, 21.6% by weight of LDPE 8.0% by weight of HDPE was used, 70% by weight of sand as an aggregate, and other additives were mixed by only 0.4% by weight of carbon black. The compounding weight% of each component is shown in Table 1, and the results obtained therefrom are shown in Table 2.

Example 4

In Example 1, 24.2% by weight of LDPE and 10% by weight of HDPE were washed, dehydrated, and dried, and 0.1% by weight of paraffin chloride, 0.1% by weight of antimony oxide, 5.0% by weight of asbestos, 0.2% by weight of iron oxide, and 0.4% of carbon black as additives. After mixing the% and 30% by weight of sand and gravel in the same process, respectively, was heated and treated. The compounding weight% of each component is shown in Table 1, and the results obtained therefrom are shown in Table 2.

Example 5

In Example 4, 11.0% by weight of LDPE and 28.2% by weight of HDPE were washed, dehydrated, and dried, and mixed and treated with the same additives except for asbestos. The compounding weight% of each component is shown in Table 1, and the results obtained therefrom are shown in Table 2.

TABLE 1

TABLE 2

* Durability test time (500 hours): corresponds to 10 years in natural state

* However, the results are the results under the extrusion pressure 33 to 38kg / cm ³ conditions.

As a result obtained from the above examples, it can be seen that as the polyethylene resin content in the total weight of the resin concrete composition increases, the strength of the composition decreases and the expansion coefficient increases, while the strength of the resin content increases. In addition, the strength was increased with the increase of gravel in the aggregate composition. In particular, these compositions have a lower compressive strength compared to general cement concrete strength, that is, compressive strength of 100 to 600 kg / cm ² , tensile strength of 20 to 70 lg / cm 2, and bending strength of 10 to 40 kg / cm 2, but they are remarkable in tensile strength and flexural strength. It can be seen that the superiority, the durability and the coefficient of thermal expansion is also improved. In addition, corrosion by acid, alkali, etc. did not occur, and insulation was improved, and cracking and shortening of life due to temperature change could be suppressed, and the curing time of the resin was also 10 minutes to 30 minutes. In particular, the economic feasibility could be improved by reducing the cross-section.

Claims (6)

The high density polyethylene and the low density polyethylene are separately washed, dehydrated and dried, followed by addition of asbestos or iron oxide as a reinforcing agent, cyanparaffin and antimony chloride as an antioxidant, and carbon black as a sunscreen, followed by mixing and melting. Polyethylene compounded resin concrete composition, characterized in that it is prepared by heating and mixing the dried aggregates into the extrusion, rolling, cooling and demolding. The method of claim 1, wherein the high density polyethylene has a water content of 0.11% or less and a density distribution of 0.941 to 0.970 g / cm ³ , and the low density polyethylene has a water content of 0.1% or less and a density distribution of 0.910 to 0.940 g / cm ³ . Polyethylene mixed resin concrete composition, characterized in that the composition of 5.0 to 12% by weight and 14 to 30% by weight of low density polyethylene. The method of claim 1, wherein the aggregate is polyethylene composite resin concrete composition, characterized in that 30% by weight of gravel having a water content of 0.1% or less and 30 to 50% by weight of sand, or 60 to 80% by weight of sand. The polyethylene blend resin composition of claim 1, wherein asbestos is added from 0 to 5% by weight of iron oxide, from 0.1 to 0.3% by weight. The polyethylene compound resin composition of claim 1, wherein paraffin chloride and antimony chloride are added in an amount of 0.05 to 0.2% by weight, respectively, as an antioxidant. The polyethylene compound resin composition according to claim 1, wherein 0.1 to 0.5% by weight of carbon black is added as the sunscreen.

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