KR100545058B1 - Waste Paper Composite Board - Google Patents

Abstract

There is provided a composite board containing waste paper which is industrial waste. The composite board is a functional composite material that recycles a huge amount of waste paper, which is one of serious wastes causing environmental pollution, and has superior properties to existing materials. Therefore, it can be applied to various fields including environmentally friendly building interior materials and consumables such as automobiles.

Waste Paper, Functional Boards, Environment Friendly

Description

Waste Paper Composite Board {WASTE PAPER COMPOSITE BOARD}             

1 illustrates an example of a manufacturing process of the waste paper composite board according to the present invention.

Figure 2a is a graph showing the bending strength measurement results of the waste paper composite board according to the present invention.

Figure 2b is a graph showing the bending strength measurement results of the waste paper composite board mixed with a flame retardant according to the present invention.

Figure 2c is a graph showing the bending strength measurement results of the waste paper composite board mixed with flame-retardant waste fiber according to the present invention.

Figure 2d is a graph showing the results of the measurement of the bending strength of the waste paper composite board mixed with flame retardant waste fiber and flame retardant 10% according to the present invention.

The present invention relates to a composite board containing waste paper which is industrial waste.

The biggest problem faced by humankind in modern society is the occurrence of environmental pollution caused by industrial wastes and other household wastes. In order to solve this problem, global attention and efforts focused on developed countries have been concentrated.

In particular, the amount of waste paper, such as waste paper and waste cardboard discharged from homes and factories, is increasing. The recycling of waste paper remains mainly at the simple stage of regenerating recycled paper by disposing waste paper in water, and so the recycling method for waste paper is still insufficient.

Sohn (1995) et al. Manufactured a board with PMDI, UF, PF resin rice by mixing paper cut to small size using various dry materials and 50:50 using dry board manufacturing method for manufacturing wood mixed composite material using waste paper. In addition, the evaluation of the wood composite composite produced showed the possibility of board manufacturing.

International research trends show that Deppe (1985) is concerned with the low peel strength and poor dimensional stability, especially when manufacturing medium density fiberboard mixed with high paper fiber through dry board manufacturing method. When used as a raw material, he explained that the "fiber-ball" phenomenon, in which the fibers spun together appear to entangle each other. If he is to produce a medium density fiber board increases the amount of paper notice fiber as thus physical and mechanical properties are reduced, and to mixed to prepare a density fiber board of the good properties of notice fibers raise the board density 800kg / m ³ or higher It is reported that the amount of resin should be increased.

Stokke and Liang (1991) produced a wood-mixed composite material by mixing 50-50 of high paper and wood raw materials (flakes, particles, thermo-based pulp wood fibers) and found that the flexural strength comparable to that of industrial boards. Although it shows properties, the peel strength is low and the thickness swelling rate is reported to increase to 25% or more. He reports that he added foamed polystyrene to reduce the thickness swelling rate, and has established a foundation for manufacturing functional boards that recycled waste paper by dry board manufacturing method through domestic and overseas research. However, systematic research for further improving flame retardancy, water resistance and practical mass production of the board should be further progressed.

On the other hand, waste paper does not require deinking process, the pretreatment process of raw material is unnecessary and biodegradable, which can reduce secondary environmental pollution after production. In addition, since waste is used as a raw material, production costs can be greatly reduced compared to existing products, and high value-added value can be created by the development of composite materials that additionally provide functionality. In particular, the eco-friendly functional composite material that recycled waste paper will have considerable competitiveness in foreign markets with strict domestic demands and environmental regulations.

Therefore, the present inventors made a composite board using the waste paper in order to find ways to utilize the waste paper, and examined the possibility of practical use by examining the physical properties and evaluating the level, and confirmed the feasibility of development as a functional composite material. The invention has been completed.

Accordingly, an object of the present invention is to examine the applicability of waste paper as a raw material of a functional composite material, and to develop a use that properly utilizes the advantages of waste paper as a recycling resource.

Another object of the present invention is to provide a composite board containing waste paper.

The present invention relates to a composite board made of waste paper, the composite board has a structure in which the waste paper is bonded by an adhesive and a hardener.

In addition, a flame retardant is further added to give a special purpose such as flame retardancy.

As used herein, "paper waste" refers to all waste paper recovered from general household or industrial waste, and examples thereof include waste paper, waste cardboard, and waste pulp obtained from waste paper waste, and the form thereof is not particularly limited. The waste paper can reduce secondary environmental pollution due to biodegradability.

In the present specification, "waste powder" means that the waste paper, which is a raw material, is obtained by crushing after cutting with a cutting machine to facilitate processing.

As used herein, "additive" refers to added to improve the mechanical, surface, chemical, aesthetic and processing properties of the board, for example, inorganic fillers, dyes and flame retardants, etc. According to the "solid additives" and "liquid additives", the kind is also not limited in the present invention.

As used herein, the term "abolition composite board" refers to a composite board made of waste paper.

The composite board of the present invention can be obtained, for example, by a general method for producing a particle board. FIG. 1 illustrates the above process, wherein a mixed raw material 101 is sprayed and mixed with an adhesive, a curing agent, and a liquid additive by using an air compressor to a powder in which solid additives are mixed into waste paper cut and crushed to a predetermined size. The moisture content of is adjusted to 8 to 14% of range, preferably to 10 to 12% of range. The dried mixed raw material 108 is placed in the mold 102 and cold-pressed by a cold press 103 to produce a mat 104, and the mat 104 is placed between two cowls 105. Thereafter, the stopper 106 is positioned on both sides of the mat 104 and then hot compressed using the hot plate 107 to complete the composite board 108 for waste paper. The completed composite board 108 has a form in which waste paper is firmly bonded by an adhesive and a hardener.

In the spraying process using an air injector during the process, the adhesive and the curing agent are sprayed in the order of the additives, which is to prevent the deterioration of the adhesive properties of the adhesive due to the additive. In addition, by appropriately adjusting the pressure of cold compression and hot compression to form pores in the composite board within the range of 3 to 20% by volume, by doing so, the mechanical strength is relatively reduced, but the sound absorption and dustproofing ability can be further improved. .

The abolition of this process can be applied to waste paper, waste cardboard and the like, which will be apparent to those skilled in the art.

The adhesive used in the composite board of the present invention is not particularly limited as long as the adhesive is applicable to paper products. The present inventors used commercially available polyvinylalchol (PVA) and urea resin adhesives for convenience. The amount of the adhesive is not particularly limited as long as it is an amount capable of maintaining the bond between the waste papers, and is usually used in an amount of 6 to 14% by weight, preferably 8 to 12% by weight based on the waste paper.

The present invention may further use a hardener or curing agent in addition to the adhesive, which is not particularly limited in the present invention. The inventors used a commercially available NH ₄ Cl curing agent for convenience. The amount of the curing agent used is usually in the range of 6 to 14% by weight, preferably 8 to 10% by weight based on the adhesive.

The composite board of the present invention can be appropriately adjusted in a range capable of maintaining appropriate mechanical strength (bending strength, peel strength, sound absorption) and physical properties (specific gravity, moisture content, water absorption rate, thickness expansion rate, etc.), thereby controlling the composite board of the present invention. When applied to the intended use it is easy to obtain the desired physical properties, for example, in addition to the biodegradability of the waste paper can be further added to the flame retardancy, sound absorption, etc. by adding an appropriate additive.

Since the color of the manufactured board is not suitable for industrial use, the dye and white carbon of the desired color are added. At this time, the content is usually used in an amount of 1 to 20% by weight, preferably 1 to 10% by weight based on waste paper.

For use as materials of construction, such as it is added to the inorganic flame retardant (FR-7 ^R) to impart flame retardancy. According to a preferred embodiment of the present invention, as the content of the added flame retardant increases, the whip strength of the manufactured composite board decreases slightly, so that the content is 10 to 20% by weight relative to the waste paper.

The composite board of the present invention can be used for various purposes by properties such as sound absorption, flame retardancy, dimensional stability, flexural strength, heat resistance, impact resistance, flame resistance, antibacterial property, and heat insulation by various additives in addition to biodegradability of waste paper.

According to a preferred embodiment, a prototype of a frame box, a gypsum board, a medium density fiberboard (MDF) and a particle board for automobile air filter as a raw material was measured and its physical properties were measured. Several physical properties also yielded results at or above the highest levels. In particular, the composite board of the present invention is capable of manufacturing a frame box using a press process, and can be manufactured in various forms-irregularities-because it is lightweight, has low thermal deformation, and has thermoforming. The gypsum board made of the composite board of the present invention has a low specific gravity and high strength as well as excellent flame retardancy by supplementing the disadvantages of the high specific gravity and low strength of the conventional gypsum board. In addition, the development of medium-density fiberboard and particle board substitutes, and the use of environmentally friendly adhesives (E ₀ , E ₁ ) can reduce the release of harmful formaldehyde. In particular, the inorganic flame retardant (FR-7 ^R ) can be processed to produce a flame-retardant board for the interior and can be applied to the construction field, it can prevent harmful gases generated by the combustion of the interior materials in the event of fire in the building. As the flame retardant, inorganic flame retardants (FR-7 ^R ) as well as flame retardant treated fibers can be used.

The specific products described above are described one example that can be produced by the composite board of the present invention, in addition to the appropriate additives can be used in accordance with each purpose of use. For example, an inorganic flame retardant (FR-7 ^R ) and flame retardant waste fibers may be used to produce a composite board having flame retardancy. Therefore, it should be construed that the present invention may further comprise additive components depending on the use used.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the scope of the present invention is not limited thereto.

<Experimental material>

-Abolition

Waste paper was used as a secondary grinding powder (less than 2 mm) in the form of powder collected by processing. The shredded waste paper was kept in a closed container so that the waste paper moisture content was less than 10% using a specially manufactured storage tank.

- glue

The adhesive was used by purchasing a PVA aqueous solution having a solid content of 14% and an aqueous urea resin solution having a solid content of 60%.

-Curing agent

The curing agent was used by purchasing an aqueous NH ₄ Cl solution.

-Flame retardant

A (main) Li 15-25% inorganic flame retardant (FR-7 ^R) dissolved in methanol was used as developed by the Im Tech. In addition, flame retardant waste fibers (10-20 mm) were used.

-White carbon

120 mesh of white carbon was used as an additive.

Example 1

Manufacture of composite board

Inject waste paper powder and white carbon into the mixer, mix it uniformly with an air compressor, and then spray with PVA adhesive (10 wt%) and urea resin adhesive (10 wt%), and then use inorganic flame retardant (FR-7 ^R ) and flame retardant. Treated waste fibers and mixed them uniformly. The water content of the homogeneously mixed raw material is controlled by the water content of the raw material and the water content of other additives, and the water content of the mixed raw material is appropriately controlled to 8 to 14% by weight, preferably 10 to 12% by weight.

In order to make a certain shape before putting the mixed raw material into the mold, it is put into a molding mold of 30cm × 30cm × 40cm (length × width × height) and cold-pressed using a screw press at a pressure of 2 kgf / cm ² . It was. After cold compression, the mold is removed, the mat is placed on the cowl, and a 1.0 cm stopper is placed on the cowl in the longitudinal direction of the mat to obtain a uniform waste paper thickness. Put on top. Then, the cowl was placed between the hot plates of the thermocompressor, and the thermostatic pressure was applied under a thermostatic pressure schedule of 50 kgf / cm ² , a thermostatic pressure temperature of 130 ° C., and a main thermostatic pressure time of 10 minutes. This reduces the pressure of the steam and prevents the mat from expanding due to the steam pressure during the curing of the adhesive inside the mat. In this state, the pressure was finally lowered once again to completely cure the adhesive in the mat, remove the cowl from the hot plate, and then remove the prepared composite was cooled to room temperature to manufacture a waste paper composite board.

Through the above process, specific gravity was 0.8 and 1.0, and a composite board having a thickness of 6 cm, 9 cm and 12 cm, respectively.

The obtained waste paper composite board was used to measure physical properties, mechanical properties and flame retardancy.

-Density, specific gravity, moisture content

Specific gravity and water content of waste paper composite boards were measured according to KS F 3104.

-Flexural strength

According to KS F 3104, one specimen of 25 cm × 5 cm × 1.0 cm was cut out from each composite material and subjected to five repeated measurements using Hounsfield's Universal Testing Machine at a load speed of 10 mm / min and span of 15 cm.

<Results and Discussion>

A. Physical Properties

a) specific gravity, moisture content

As shown in Table 1, the average moisture content of the abolished composite board of the present invention was 8.32%.

Pageboard Soft fiber board Medium density fiberboard Rigid fiberboard Gypsum board (1.25cm thick) importance 1.00 <0.35 0.35 to 0.85 0.85 < 0.75 to 1.13 Water content 8.32% 5 to 13% 5 to 13% 5 to 13% <3%

B. Mechanical Properties

a) flexural strength

Flexural strength of the waste paper composite board according to the present invention is shown in Figures 2a to 2d.

Figure 2a is a graph showing the bending strength according to the specific gravity and thickness of the waste paper composite board containing no flame retardant, the specific gravity of the composite board was 1.0 showed that the bending strength is superior to that of 0.8, the flexural strength by thickness of the composite board It can be seen that there is no difference. Figure 2b is a graph showing the bending strength according to the content of the flame retardant of the composite board (specific gravity 1.0, thickness 9 mm) containing the inorganic flame retardant (FR-7 ^R ), it can be seen that the flexural strength decreases as the content of the flame retardant increases. The results were better than gypsum board and soft board. Figure 2c is a graph showing the bending strength according to the content of the waste fiber of the composite board (specific gravity 1.0, thickness 9mm) mixed with the flame retardant treated flame retardant, showing the same trend as in Figure 2b. Figure 2d is a graph showing the flexural strength according to the content of the waste fiber in the composite board using the inorganic flame retardant (FR-7 ^R ) and flame retardant treated waste fiber, as shown in Figure 2b and 2c As this increases, the flexural strength decreases. However, in all of the above experiments, it was found that the flexural strength is much superior to that of the conventional gypsum board and the softening board. This result is considered to be because the flexural strength is increased by the cellulose component contained in the waste paper and the components are firmly bonded due to the adhesive or the like. Also overall, medium density fiberboard (2,150 psi (15 type)) and rigid fiberboard (2,870 psi It shows lower flexural strength than (S20 type)) but significantly higher than soft board (15 psi) and gypsum board (400 psi), so it can be suitably used as a functional building material for flame retardancy. can do. In particular, the abolished composite board of the present invention is due to the characteristics of low specific gravity and high strength, it is judged that it is possible to be an excellent substitute of gypsum board with a high specific gravity and weak strength in the raw material properties.

C. Flame Retardant

10, 15 and 20% by weight addition of an inorganic flame retardant (FR-7 ^R) to impart flame retardancy to 1.0 specific gravity, was produced a composite board having a thickness of 9mm, measure the flame retardant as follows on the basis of JIS A 1321-1994 It was.

-Coefficient of smoke (C _A )

The coefficient of smoke per unit area was measured based on the following equation, and the flame retardant class 1 was classified as 30 or less, the flame retardant class 2 was 60 or less, and the flame retardant third class was 120 or less.

C _A = 240 log (I _o / I)

I _o : Light intensity at the start of the heating test (lx)

I: minimum value of light intensity during heating test (lk)

-Surface area (℃ × min)

The area of the exhaust temperature curve where the exhaust temperature curve exceeded the standard temperature curve and the area surrounded by the standard temperature curve was classified as 100 or less for the second flame retardant and 350 or less for the third flame retardant.

-Weight loss (%)

The weight loss rate was measured by measuring the weight before and after the heating test.

-Ignition time

The time taken to start ignition after the start of heating was measured.

Afterglow time

The duration of residual flame after heating was measured.

-Oxygen index

The oxygen index of the composite board was measured according to ASTM D 2863.

Evaluation item Content of flame retardant (%) 10 15 20 importance 1.0 1.0 1.0 Smoke coefficient C _A 24 15.7 6.75 Ammunition ℃ min 119 67.5 50 Weight loss rate % 18.15 13.78 12.1 Ignition time sec 99 103.33 127.5 Afterglow time min 75 65 57.5 Oxygen index 29.1 31.2 35.11

According to Table 2, as the content of the inorganic flame retardant (FR-7 ^R ) is increased, the flame retardancy is excellent, especially in the case of the coefficient of smoke all obtained the results corresponding to the flame retardant class 1, in the case of the burn area The content of 10% by weight of the flame retardant class 3, the rest of the flame retardant class 2, etc. showed very good results.

In the case of the oxygen index is also a value indicating the minimum concentration of oxygen in the air to burn the specimen, it was confirmed that the flame retardancy is excellent as the content of the inorganic flame retardant (FR-7 ^R ) increases as the content increases.

conclusion

As a result of evaluating and testing the physical and mechanical properties of the waste paper composite board recycled from waste resources and conducting a basic research on the possibility of manufacturing the composite material, the following conclusions were obtained.

1. The specific gravity and a low water content high specific gravity according to the conventional bending strength is superior revealed the excellent potential as alternative material for the low strength of gypsum board, especially in the non-built-noncombustible building as the addition of inorganic flame retardant (FR-7 ^R) It turned out that it is suitable as a material.

2. As a result of the flexural strength test, the higher the specific gravity, the higher the flexural strength value, and the higher the content of the flame retardant, the lower the value was, but it was significantly higher than the conventional soft board and the gypsum board.

3. In order to impart flame retardancy to the manufactured waste paper composite board, an inorganic flame retardant (FR-7 ^R ) was added to confirm the excellent flame retardant effect. This means that if the waste paper composite board of the present invention is to obtain physical properties other than flame retardant properties, additives corresponding thereto may be appropriately used.

4. The utilization of recycled waste functional composite materials as building materials has great significance in that it can develop materials that perform better than existing materials and can also reduce environmental pollution factors by recycling waste resources. something to do.

As described above, the composite board of the present invention is characterized in that it is a functional composite material that recycles a huge amount of waste paper, which is one of the serious wastes causing environmental pollution, and not only has superior characteristics than conventional wood boards. In addition, it is significant in that the recycling of waste resources can reduce the causes of environmental pollution. In other words, it is expected to provide a material with better performance than existing materials, to recycle the advantages of waste paper as a recycling resource, and to reduce the production cost of building materials.

In addition to the biodegradability of the waste paper can be used in various applications by the properties such as sound absorption, flame retardancy, dimensional stability, flexural strength, impact resistance, flame resistance and thermal insulation by various additives. Furthermore, it can be easily utilized as industrial or building materials, such as a frame box for automobile air filters, gypsum goods, a medium density fiber board, or a particle board.

Claims (6)

Dry waste powder; Adhesive 6-14% by weight based on the weight of the waste paper powder; 6-14% by weight of hardener based on the weight of the waste paper powder; Waste paper composite board manufactured by dry molding a water content of 8-14% mixed raw material comprising a 10-20% by weight relative to the weight of the waste paper powder. The waste paper composite board according to claim 1, wherein the dry waste paper powder is selected from the group consisting of waste newspaper paper powder, waste cardboard paper powder, waste pulp powder obtained from paper waste paper, and a mixed composition thereof. delete delete delete delete

Images