KR100376231B1 - Polymer concrete foam and preparation method thereof - Google Patents

Abstract

The present invention relates to a foamed polymer concrete and a method for manufacturing the same, specifically, a polymer composed of 15 to 50% by weight of thermosetting polymer resin, 0 to 80% by weight of sand, 5 to 50% by weight of filler and 0.1 to 1.5% by weight of blowing agent. Foamed polymer concrete produced using a concrete composition and a method for producing foamed polymer concrete, characterized in that the composition is heat-treated at 100 to 200 ℃ for 30 minutes to 2 hours to cure simultaneously with foaming to form pores therein. The foamed polymer concrete according to the present invention may be used as a structural material because it has excellent mechanical strength and lightness, as well as heat insulation and sound insulation effects.

Description

Polymer concrete foam and preparation method

The present invention relates to a foamed polymer concrete and a method for manufacturing the same, specifically, a polymer composed of 15 to 50% by weight of thermosetting polymer resin, 0 to 80% by weight of sand, 5 to 50% by weight of filler and 0.1 to 1.5% by weight of blowing agent. Foamed polymer concrete produced using a concrete composition and a method for producing foamed polymer concrete, characterized in that the composition is heat-treated at 100 to 200 ℃ for 30 minutes to 2 hours to cure simultaneously with foaming to form pores therein. will be.

There are generally three methods for producing polymer concrete.

The first method is PCC (Polymer-modified cement concrete) which supplements the strength by adding organic polymer to the existing Portland cement binder. This method consists of a structure that protects the interior by forming a polymer film layer on the cement layer simultaneously with the hydration of the cement by mixing the emulsified particles or polymer powder or monomer thereof that can be dispersed with the cement binder and water.

The second method is PC (Polymer concrete) using pure polymer as a binder of aggregate. Since this method uses a polymer as a binder, it is generally evaluated to be superior in strength, adhesion, durability, weather resistance, and chemical resistance to concrete.

The third method is PIC (Polymer Impregnated Concrete) in which concrete material made of hardened cement is impregnated with polymer monomer, but it is not used well because it is difficult and expensive in practical application.

The polymer concrete as described above uses polymer instead of cement as a binder, so it is not easy to penetrate moisture or air, so it has excellent durability against the external environment, and general Portland Simet is used as a binder due to its strong binding strength between polymer and aggregate. It is known that the compressive and flexural strength is superior to that of cement concrete. Therefore, it may be used for the manufacture of communication menholes or radioactive waste containers requiring long-term durability, and is used for repair work on bridges, highways, and parking lots made of ordinary concrete. However, the problem of cure shrinkage could not be avoided because a thermoplastic resin was used as the polymer resin.

On the other hand, lightweight foamed concrete is generally produced by generating bubbles by using an antifoaming agent and water in concrete mortar. Such lightweight foam concrete is a low specific gravity light material is widely used as a heat dissipation, sound insulation and vibration prevention material, but is not used as a structural material because it does not have sufficient strength.

As described above, the conventional polymer concrete is poor in mechanical properties such as strength, and has a problem of hardening shrinkage due to the use of a thermoplastic resin, and thus there is a limit to use it as a substitute for concrete.

Accordingly, the present inventors have made efforts to solve the above problems, as a result of using a thermosetting polymer resin instead of a thermoplastic resin as a polymer concrete component and adding a blowing agent, unlike the conventional foam polymer concrete is produced through a manufacturing method that occurs simultaneously with foaming and curing The present invention has been completed by finding that the mechanical properties are improved and there is no problem of cure shrinkage.

It is an object of the present invention to provide a polymer concrete composition of new composition.

It is also an object of the present invention to provide a foamed polymer concrete having excellent mechanical strength prepared using the composition and a method for producing the same.

In order to achieve the above object, the present invention provides a polymer concrete composition comprising a thermosetting polymer resin and a blowing agent.

In another aspect, the present invention provides a foamed polymer concrete prepared by the polymer concrete composition and a method for producing the same.

Hereinafter, the present invention will be described in detail.

The polymer concrete composition according to the present invention is characterized by containing a thermosetting polymer resin and a blowing agent. In the conventional polymer concrete, a thermoplastic resin was used, but mechanical properties such as strength were poor, and there was a problem in that curing shrinkage occurred. In contrast, in the present invention, the mechanical properties of the polymer concrete are improved by using the thermosetting resin. In addition, the polymer concrete composition according to the present invention includes a foaming agent, thereby alleviating the problem that the polymer concrete produced by the composition is cured shrinkage.

Specifically, the polymer concrete composition according to the present invention is preferably composed of 15 to 50% by weight of thermosetting polymer resin, 0 to 80% by weight of sand, 5 to 50% by weight of filler and 0.1 to 1.5% by weight of blowing agent.

More preferably, the polymer concrete composition is composed of 15 to 25% by weight of thermosetting polymer resin, 45 to 60% by weight of sand, 10 to 30% by weight of filler and 0.7 to 1.4% by weight of blowing agent.

If the content of the resin is too small, the binding force between the particles is weak and the pores are not formed well, so it is preferable to add the composition ratio as described above.

Although sand is not included in the composition, it is possible to prepare a foamed hardened body, that is, foamed polymer concrete, and the content of sand is not limited in manufacturing foamed polymer concrete using the polymer concrete composition.

If no filler is included, the pore formation may be poor when preparing the cured product using the composition. However, the filler is preferably added in an amount of not more than 50 wt%, and more preferably 5 to 50 wt%, more preferably 10-30 weight% is added.

When the blowing agent exceeds a certain content, the foaming efficiency is reduced because the polymer concrete composition is not sufficiently foamed under the influence of internal pressure. Therefore, in the present invention, 0.1 to 1.5 wt%, more preferably 0.7 to 1.4 wt% is added.

In the polymer concrete composition according to the present invention, the thermosetting polymer resin is preferably used selected from the group consisting of unsaturated polyester resins, epoxy resins, polyurethane resins, acrylate resins and styrene resins. More preferably, unsaturated polyester resin is used.

Generally, polymer resins such as epoxy resins, polyurethane resins, acrylate resins and unsaturated polyester resins are used for polymer concrete. Epoxy resin is difficult to control the hardening behavior, but it is difficult to manufacture concrete, but it has advantages such as low shrinkage rate and strong bonding strength with the aggregate. Polyurethane, like epoxy resin, is bonded through a condensation reaction, so it may not be easy to control the curing reaction. On the other hand, since the acrylate resin or the unsaturated polyester resin is cured through a radical reaction, the solidification can be easily controlled. In particular, acrylate resins are highly volatile and may not have sufficient binding strength with aggregates, but since they mainly use methyl methacrylate (methyl methacrylate, MMA) as a monomer, they can be easily mixed with aggregates due to their low viscosity. Unsaturated polyester is the most widely used material as a polymer concrete binder, and has the advantage of good binding strength and high molecular weight. The polymer resin, such as a liquid unsaturated polyester, contains a plurality of unreacted double bonds in one molecule, and this part induces curing while undergoing a radical reaction. In addition to the unsaturated polyester, styrene monomer can be added to the inside of the resin as a diluent to lower the viscosity of the resin, thereby improving workability and controlling the degree of crosslinking.

In general, the resin is reacted using a curing agent, but in the present invention, a curing reaction can be induced only by applying heat without using a curing agent. This is because the present invention not only induces a radical reaction of the resin by applying heat to the polymer concrete composition, but also simultaneously advances foaming. Therefore, the resin that can be used in the polymer concrete composition of the present invention includes all kinds of resins capable of thermosetting, in addition to the above-mentioned kinds.

In the polymer concrete composition according to the present invention, the sand preferably has an average diameter of 1 mm or less, and more preferably, fine sand having an average diameter of 1 to 0.1 mm. The smaller the size of sand is, the more uniform the distribution of pores to be foamed. In addition, when the grains of sand are large, a problem may occur in that the resin layer and the sand layer are separated due to the load of sand, and may become uneven as a whole when the volume of the cured body is expanded.

The filler is preferably calcium carbonate (CaCO ₃ ) or fly ash, more preferably an average diameter of 0.001 to 0.1 mm. Calcium carbonate or fly ash fine powder acts to permeate the sand to reduce the required amount of resin and increase the mechanical strength of the cured body. In addition, the filler prevents the gas generated during foaming from escaping to the outside through the gap between the sand and significantly delays the bonding of the pores during the curing time. Therefore, in the present invention, the foamed process is more efficient for the cured product to which the filler is added than the cured product composed of only resin and sand.

The blowing agents of the present invention can be used as long as the compound generates gas by chemical action by heat, and is generally in the form of fine powder. Preferably, an azo compound is used.

In addition, the polymer concrete composition according to the present invention may further comprise a hardener 0.2% by weight or less in addition to the polymer concrete composition. In this case, it is preferable to use a peroxide-based compound for the curing agent.

In another aspect, the present invention provides a foamed polymer concrete prepared from the polymer concrete composition.

In another aspect, the present invention provides a method for producing expanded polymer concrete, characterized in that the polymer concrete composition is heat-treated at 100 to 200 ° C for 30 minutes to 2 hours to cure simultaneously with foaming to form pores therein.

In general, the polymer concrete containing the resin is reacted using a curing agent, but in the present invention, the curing reaction can be induced only by applying heat without using the curing agent.

On the other hand, in this invention, conditions of foaming temperature and hardening temperature are important. This is because when the curing proceeds first, it is not foamed, and when curing occurs after a long time after foaming, foamed polymer mortar and uncured polymer mortar are separated. Therefore, it is necessary to allow the polymer concrete composition to cure immediately after foaming. In addition, if the temperature is too low, the foaming efficiency is lowered, and if the temperature is lowered, thermal curing does not occur. On the other hand, if the temperature is too high, the curing speed is faster than the foaming speed, and if the temperature is higher, the organic binder, that is, the thermosetting resin, may be pyrolyzed. In view of the above factors, the foaming and curing temperatures are preferably similar to the lower limit foaming temperature of the blowing agent used, more preferably 100 to 200 ° C in the present invention.

Hereinafter, the present invention will be described in more detail with reference to Examples.

However, the following examples are illustrative of the present invention, and the content of the present invention is not limited by the examples.

Examples 1 to 13 Preparation and Properties of Foamed Polymer Concrete

The polymer concrete composition of the composition ratio as shown in Table 1 was mixed and foamed polymer concrete was prepared under the temperature and time conditions of Table 1.

The molding mold consists of two types of aluminum molds (25 mm diameter, 50 mm long, 5 cylindrical in series, and 5 mm thick, 20 mm wide, 20 mm wide, 90 mm long beam shaped frames arranged in series). Was used. The mold was sealed with a metal plate at the top, and two windows 2mm wide x 3mm thick were symmetrically formed on the top of the mold so that the overflowed contents escaped to the outside. The mold containing the mixture was allowed to stand and foamed in a preheated hot room for a predetermined time. After the test, the cured test piece was pulverized to check the presence of pores and the size of the pores.

Unsaturated polyester resin as binder was KL-103 (III liquid) (Aekyung Chemical), sand was used as intrinsic material 6 silica sand with a diameter of 0.2 to 0.6 mm, and calcium carbonate powder (first-class reagent) as a filler. (Oriental Chemistry) was used.

The blowing agent used was UNICELL-D1100 (Dongjin Semichem) having a foaming temperature of 200 to 230 ° C. and UNICELL-DL31 (Dongjin Semichem) having a foaming temperature of 140 to 145 ° C. UNICELL-D1100 is an azodicarbonamide (Azodicarbonamide or Azobisformamide) -based material and is known to be an effective blowing agent for general plastics and rubber, and is capable of foaming at temperatures lower than the actual foaming temperature of 200 to 230 ° C. In addition, UNICELL-DL31 is a material that has a rapid decomposition rate by modifying azodicarbonamide.

The curing agent was methyl ethyl ketone peroxide (MEKP, Aekyung Chem) and the curing accelerator was Cobalt Octoate (Aekyung Chem). The surfactant used was sodium dodecylbenzene sulfonate (Junsei Chemical), and the coagulant used paraffin having a melting point of 60 to 70 ° C. In all the examples below, the materials and molds used are as mentioned above unless otherwise specified.

Polymer Concrete Compositions and Foaming Conditions Example Number Content of polymer concrete composition (g) Firing conditions Suzy Hardener sand Filling blowing agent Surfactants Temperature (℃) time One 17 0.34 66.4 16.6 0.68 ^a 0 190 One 2 17 0 66.4 16.6 0.68 ^a 0 190 One 3 17 0 60 16 0.68 ^a 0 170 2 4 17 0 60 16 0 ^a 0 170 2 5 17 0 60 16 1.4 ^a 0 170 2 6 17 0 60 0 0.68 ^a 0 170 2 7 36 0 60 16 0.68 ^a 0 170 2 8 17 0 0 16 0.68 ^a 0 170 2 9 17 0 60 ^c 16 0.68 ^a 0 170 2 10 27.5 0 60 20 0.68 ^b 0 150 2 11 20 0 64 20 0.7 ^b 2.7 150 2 12 20 0 64 20 0.7 ^b 0.2 150 2 13 28 0 0 28 0.7 ^b 0 110 - a: UNICELL-D1100 (foaming temperature 200-230 ℃, Dongjin Semichem) b: UNICELL-DL31 (foaming temperature 140-145 ℃, Dongjin Semichem) c: crushed rock with a diameter of about 10 mm instead of sand

(1) Influence of Addition of Curing Agent (Examples 1 to 2)

In the case of Example 1 containing a curing agent, it was confirmed that the prepared cured product (foamed polymer concrete) had a small amount of fine pores having a diameter of 1 mm or less therein. In this case, it was determined that the curing of the polymer concrete proceeds faster than the foaming due to the effect of the curing agent.

On the other hand, in the case of Example 2, which is the same condition as Example 1 except not including a curing agent, it was confirmed that the prepared cured body had relatively large pores having a diameter of 0.1 to 5 mm therein. In this case, since the foaming temperature was set to 190 ° C, which is a relatively high temperature, some of the styrene monomers contained in the resin evaporated to the outside.

(2) Influence by Changes in Components and Ratios of Polymer Concrete Compositions (Examples 3 to 9)

In the case of Example 3 in which the content of the blowing agent was 0.68 g (0.73 wt%), pores of relatively large size were formed in the cured product. At this time, the cured product could be foamed at 170 ° C., which is lower than the foaming temperature of 200 to 230 ° C. of the material used as the blowing agent, and the gas generation rate was only slowed down.

In the case of Example 4, which was the same condition as Example 3 except that no blowing agent was added, air pores were found on the surface of the cured product. However, when the hardened | cured material was grind | pulverized and the inside was observed, it was not found that the pores were formed visually. The pores on the surface are thought to be formed by evaporation because the boiling point of the styrene monomer contained in the unsaturated polyester is low.

For Example 5, the same conditions as in Example 3 except that the content of the blowing agent was increased to 1.4 g (1.48% by weight), the cured product produced did not show a significant increase in the amount of foaming. This is thought to be because the pressure inside the mold prevents expansion due to foaming.

In Example 6, which was the same condition as Example 3 except that no filler was added, no pores could be found in the cured product. This is thought to be because all of the gas already generated from the blowing agent has escaped to the outside before curing.

In the case of Example 7, which was the same condition as Example 3 except that the resin was added in an excessive amount of 36 g (61.9 wt%), the amount of foaming was increased. However, sand was concentrated in the lower part of the cured body, and resin and filler were distributed in the upper part rather than sand component. In addition, due to the large number of resin components, the viscosity of the polymer mortar becomes low, and the sand settled before curing due to the density difference between the sand and the resin.

Except that no sand was added at all, in Example 8, which was the same as in Example 3, many large pores were found in the prepared cured product. On the other hand, there was a disadvantage in that the hardened body is easily broken even in a weak impact.

For Example 9, the same conditions as in Example 3, except that crushed rock having a uniform size of about 10 mm in diameter was added instead of sand, large pores were found in the hardened body. Could. However, although the volume of the cured body expanded due to the foaming, there was a disadvantage in that the aggregate did not move and only the remaining components expanded.

(3) Effect according to the type of blowing agent (Example 10)

In the case of Example 10 foamed at 150 ° C using a foaming agent having a lower foaming temperature (foaming temperature of 140 to 145 ° C) than the foaming agent used in Example 3 (foaming temperature of 200 to 230 ° C), the prepared cured product was pulverized to The difference in porosity and weight produced in was investigated, but no difference in foaming effect was found in comparison with the case of Example 3.

(4) Effect of Addition of Surfactant (Examples 11 to 12)

In general, surfactants are added to improve the stability of the resin, sand and the resulting gas in the polymer mortar. In the polymer concrete composition according to the present invention, it was examined whether such an effect can be obtained by adding a surfactant.

In Example 11, in which 2.7 g of a surfactant was added, the prepared cured product had a disadvantage in that the distribution of pores was uneven because internal pores were concentrated at the center of the cured body. In addition, the paraffin coagulant applied to the mold die was mixed into the hardened body under the influence of the surfactant, and the reactivity between the mold die and the hardened body became poor.

In Example 12, which was the same condition as Example 11 except that the content of the surfactant was reduced to 0.2 g, pores were collected in the inner center of the cured body. Reaction between the mold die and the cured product was better than Example 11, but still poor.

(5) foaming time change according to the foaming temperature (Example 13)

Example 13 was removed at a low temperature of 110 ° C. in a transparent bottle with an open top using a blowing agent (foaming temperature of 140 to 145 ° C.) lower than the blowing agent used in Example 3 (foaming temperature of 200 to 230 ° C.). Foamed. At this time, after the heat treatment was started, the bubble was formed in the mortar in the bottle after about 10 to 20 minutes and expanded, and the experiment was repeated five times, but the time to start foaming was constant.

Examples 14 to 20 Preparation and density analysis of foamed polymer concrete

The polymer concrete composition of the composition ratio as shown in Table 2 was mixed and the mold containing the mixture was left in a high temperature room heated to the high temperature of Table 2 for 2 hours to prepare a foamed polymer concrete. At this time, the resins, sand and fillers were those described in Examples 1 to 13, and the blowing agent used UNICELL-DL31 (Dongjin Semichem) having a foaming temperature of 140 to 145 ° C. Cylindrical specimens prepared as described above (moulds are used in those described in Examples 1 to 13) were measured and the density of the specimens was calculated based on the results, and the results are shown in Table 2 below.

Composition ratio, foaming temperature and density of hardened body of the polymer concrete composition Example Number Content of polymer concrete composition (g) Foam temperature (℃) Density ^a (g / cm ³ ) Suzy sand filling blowing agent 14 140 300 120 4 170 1.631 ± 0.088 15 140 250 170 4 170 1.725 ± 0.006 16 140 400 120 4 170 1.739 ± 0.043 17 140 300 120 8 170 1.437 ± 0.014 18 140 300 120 8 100-110 1.805 ± 0.008 19 140 300 120 8 140 1.470 ± 0.006 20 140 300 120 8 150 1.533 ± 0.007 a: mean of five specimens

As can be seen in Table 2, it was confirmed that the overall density is small and uniform, so that many pores are produced in the polymer concrete according to the present invention, thereby achieving a lightening effect. On the other hand, when a small amount of blowing agent was added (Example 14, 0.7 wt%), the density was lower when more blowing agents were added under the same conditions (Example 17, 1.4 wt%). For sand the density slightly increased (53.2% by weight of Example 14 and 60.2% by weight of Example 16) with increasing content. In the case of the foaming temperature, the density was the lowest when the foaming temperature of the foaming agent was equal to 140 to 145 ° C., and the density was slightly increased in the case of higher or lower than that, but still showed excellent density.

As described above, when the expanded polymer concrete is manufactured using the polymer concrete composition according to the present invention, the density thereof is small, thereby achieving a light weighting effect, and since the pores are contained in the interior, the thermal conductivity is low and the soundproofing and heat insulating effect is excellent. .

Examples 21 to 24 Preparation of Foamed Polymer Concrete Using Modified Molds

In order to investigate the effect of the mold structure on the properties of the polymer concrete, the following experiment was conducted using the modified mold.

Odd-numbered compartments of two types of molds: 5 cylindrical in diameter 25 mm, 50 mm long, arranged in series and 5 beam form frames in 20 mm thick, 20 mm wide, 90 mm long To fill the polymer concrete composition of Table 3 below. The upper part of the mold was sealed with a metal plate, and two windows 2 mm wide x 3 mm thick were symmetrically formed at the top of the mold to foam the overflowing contents to the outside. Separately, two symmetrical windows, 15 mm wide x 2 mm thick, were created on the top of the mold to ensure that the overflowed contents flow smoothly into the next compartment. The mold containing the polymer concrete composition was left in a high temperature room previously warmed to the foaming temperature of Table 3 for two hours to prepare foamed polymer concrete. The composition ratio of the polymer concrete composition used in this example, the foaming temperature and the density of the prepared foamed polymer concrete (hardened body) are shown in Table 3 below.

Composition ratio, foaming temperature and density of hardened body of the polymer concrete composition Example Number Content of polymer concrete composition (g) Foaming temperature (℃) Density ^a (g / cm ³ ) Suzy sand filling blowing agent 21 98 210 84 5.6 130-140 1.350 ± 0.044 22 98 210 84 5.6 140-150 1.427 ± 0.010 23 98 210 84 2.8 140 1.335 ± 0.030 24 130 130 130 5.6 140 1.175 ± 0.009 a: mean of three specimens

The foamed polymer concrete of Examples 21 and 22 prepared in a modified mold using a composition having a composition of resin: sand: filler: foaming agent = 24.6: 52.8: 21.1: 1.4 in weight ratio, each having a density of 1.350 ± 0.044 g, respectively. / Cm 3, 1.427 ± 0.010 g / cm 3. On the other hand, the polymer concretes of Examples 19 and 20 prepared with the same composition ratio were 1.470 ± 0.006 g / cm 3 and 1.533 ± 0.007 g / cm 3, respectively. That is, when the modified mold was used, it was found that bubbles were generated more smoothly when foaming under the same conditions, resulting in a smaller density. Therefore, when foaming the cured product, it was found that it is important to improve the mold mold so that the contents are not subjected to pressure.

On the other hand, in Example 23, the amount of blowing agent was reduced by half compared to Examples 21 and 22, but the density of the prepared polymer concrete was still excellent, at 1.335 ± 0.030 g / cm 3. That is, when the amount of the blowing agent is a certain amount or more it was found that the foaming effect no longer increases.

Example 25 Preparation of Foamed Polymer Concrete without a Mold

In order to investigate the properties of the foamed polymer concrete when the mold is not used, the polymer concrete composition was manufactured in the form of a sheet in a thin space.

50 g of the polymer concrete composition having the same composition ratio as in Example 22 was heat-treated at 140 ° C. in a space of 10 mm in height made of a metal plate. Sufficient empty space was provided on all sides so that the polymer mortar foamed freely and expanded in the 360 degree direction. Sheets made at this time had the advantage of abundant pores compared to the cured product made in the mold, but had a disadvantage in that the mechanical strength was somewhat reduced.

Comparative Example Preparation of Foam-Free Polymer Concrete

The polymer concrete cured at room temperature without foaming was prepared and compared with the foamed polymer concrete of the present invention.

Mix 300 g of aggregate, 120 g of filler, 2 g of methyl ethyl ketone peroxide as a curing agent, 4 mg of cobalt octoate as a curing accelerator for curing at room temperature and 140 g of resin (the composition ratio is Same as Example 24), two types of molds (25 mm in diameter, 50 mm in length and 5 cylinders arranged in series and 5 mm in thickness, 20 mm in width and 5 mm in length, in the form of 5 frames arranged in series) were respectively filled. . The upper part of the mold was sealed with a metal plate and cured at room temperature for one day to prepare a foamless polymer concrete. As a result of calculating the density by measuring the weight of the prepared cylindrical specimen, it was very high as 1.964 ± 0.007 g / cm 3.

Experimental Example 1 Shrinkage Measurement

Generally, there is a problem of curing shrinkage in the production of polymer concrete, but the polymer concrete according to the present invention does not cure shrinkage due to expansion characteristics during foaming because foaming and curing occur simultaneously.

On the other hand, the heat shrinkage phenomenon appeared while cooling to room temperature after thermosetting. Table 4 shows the results of examining the diameter size of the cylindrical polymer concrete manufactured using the cylindrical mold with the composition of Examples 21 to 23.

Heat shrinkage results Example number Cylinder diameter reduction rate 21 0.8 to 1.0% 22 0.8 to 1.0% 23 1.6% 24 1.8%

For Example 21 and Example 22, the heat shrink was minimal. On the other hand, in the case of Example 23, the diameter reduction rate slightly increased to 1.6%, which is considered to be due to the decrease in the amount of blowing agent. In addition, in the case of Example 24, the diameter reduction rate was slightly increased to 1.8%, which is considered to be due to the fact that the thermal shrinkage occurred much higher than that of other examples. However, in all cases, since the heat shrinkage rate was extremely small, less than 2%, it was judged that it is not necessary to add a shrinkage inhibitor which is generally added in the production of the polymer concrete according to the present invention.

Experimental Example 2 Mechanical Strength Measurement

The strength was measured for the polymer concrete prepared in Examples 14-24.

In the compression test, a cylindrical specimen having a diameter of 25 mm and a length of 50 mm was applied by a compression tester to measure the force at break, and the compressive strength was calculated by dividing the magnitude of this force by the cross section of the specimen. In the bending test, a beam-shaped specimen having a thickness of 20 mm, a width of 20 mm, and a length of 90 mm was subjected to a three-point bending strength test using a compression tester with a span spacing of 50 mm. The intensity was calculated.

Flexural Strength = (3 × Span × Breaking Strength) / (2 × Width × Thickness 2)

The results are shown in Table 5 below.

Mechanical strength Example number Compressive strength (kgf / cm ² ) Flexural strength (kgf / cm ² ) 14 516 ± 11 166 ± 10 15 627 ± 01 225 ± 07 16 265 ± 30 165 ± 12 17 480 ± 27 150 ± 24 18 624 ± 01 235 ± 10 19 523 ± 06 169 ± 05 20 574 ± 17 191 ± 09 21 317 ± 23 126 ± 11 22 437 ± 08 156 ± 09 23 173 ± 05 - 24 304 ± 27 142 ± 13 Plain cement concrete ^a To 200 ~ 40 a: References "Composition and Properties of Concrete", G.E. Troxell et., 2nd Ed., McGRAW-HILL Com., p231.

As can be seen in Table 5, the mechanical strength of the polymer concrete according to the present invention was superior to that of general cement concrete.

On the other hand, Examples 14 to 16 had similar densities, but as shown in Table 5, when more filler was added than sand (Example 15), the strength was excellent. In addition, in Examples 17 to 20 with different foaming temperatures under the same conditions, when the foaming temperature was low (Example 18), the density was slightly higher but the mechanical strength was excellent.

Experimental Example 3 Thermal Conductivity Measurement

The thermal conductivity of the polymer concrete according to the present invention is determined by the hot wire method (KS L 3306, a hot wire is inserted between two specimen surfaces (20 mm × 40 mm) and the temperature of the inner and outer surfaces is measured to obtain thermal conductivity). Was measured. The specimens used were 10 mm thick, 20 mm wide, and 40 mm long. The hot wire was used as a clean surface with no holes.

Thermal conductivity Example number 21 22 24 25 Comparative example General Cement Concrete Thermal Conductivity (Wm ^-1 K ^-1 ) 0.465 0.550 0.392 ^a 0.397 1.167 1.4 to 3.6 ^b a: Since the specimen of Example 24 had many pores on the surface, the thermal conductivity may be slightly different due to contact with the hot wire. b: Reference "properties of Concrete", A.M. Neville, 3rd ed., Pitman Publishing Ltd., p488.

As can be seen in Table 6, in the comparative example of the non-foamed polymer concrete, the thermal conductivity is 1.167 Wm ⁻¹ K ^−1, and in the case of general cement concrete, 1.4 to 3.6 Wm ⁻¹ K ⁻¹ is common. On the other hand, the polymer concrete according to the present invention had excellent thermal conductivity of about 0.5 Wm ⁻¹ K ⁻¹ or less. Therefore, the polymer concrete according to the present invention is expected to have excellent thermal insulation effect and can be usefully used as a building material.

As described above, the foamed polymer concrete according to the present invention has mechanical strength superior to that of general cement concrete in bending strength and compressive strength, and the problem of hardening shrinkage, which has been pointed out as a problem in general polymer concrete by adding a blowing agent, It was solved. In addition, since the pores are formed inside, the weight can be reduced, and the sound insulation and vibration prevention effect is excellent, and the thermal conductivity is small, and the heat insulation effect is excellent. Therefore, the foamed polymer concrete according to the present invention can be used as a general structural material, and when used as a building structural material can significantly reduce the requirements of heat dissipation, sound insulation, and vibration prevention materials additionally installed in addition to the structural material. Using, it can be usefully used as a prefabricated building structural material to make a structural material in advance and then transport and install it where necessary.

Claims (10)

A polymer concrete composition composed of 15 to 50% by weight of thermosetting polymer resin, 0 to 80% by weight of sand, 5 to 50% by weight of filler and 0.1 to 1.5% by weight of blowing agent. The polymer concrete composition of claim 1, further comprising 0.2 wt% or less of a curing agent in addition to the component. The polymer concrete composition according to claim 1 or 2, wherein the thermosetting polymer resin is selected from the group consisting of unsaturated polyester resins, epoxy resins, polyurethane resins, acrylate resins and styrene resins. The polymer concrete composition according to claim 1 or 2, wherein the sand has an average diameter of 1 mm or less. _{3. The} polymer concrete composition of claim 1, wherein the filler is calcium carbonate (CaCO ₃ ) or fly ash. 4. 6. The polymer concrete composition according to claim 5, wherein the filler has an average diameter of 0.001 to 0.1 mm. The polymer concrete composition according to claim 1 or 2, wherein the blowing agent is an azo compound. The polymer concrete composition of claim 2, wherein the curing agent is a peroxide-based compound. Foamed polymeric concrete made from the polymeric concrete composition of claim 1. The method of claim 1, wherein the polymer concrete composition of claim 1 is heat-treated at 100 to 200 ° C. for 30 minutes to 2 hours to cure simultaneously with foaming to form pores therein.