KR20120136002A

KR20120136002A - Synthetic wood with enhaced flame refardancy and bending strength and manufacturing method thereof

Info

Publication number: KR20120136002A
Application number: KR1020110054950A
Authority: KR
Inventors: 박유홍
Original assignee: (주)와이엠산업
Priority date: 2011-06-08
Filing date: 2011-06-08
Publication date: 2012-12-18

Abstract

PURPOSE: Synthetic wood with improved fire retardant property and flexural strength, and a producing method thereof are provided to prevent the carbonization of wood powder. CONSTITUTION: Synthetic wood with improved fire retardant property and flexural strength contains less than 5% of water, and is produced with 50-70wt% of wood powder, 20-30wt% of synthetic resin, 2.5-7.5wt% of surfactant, 5-15wt% of yellow soil, and 2.5-7.5wt% of acrylic acid. The synthetic wood has carbonization prevention and non-discoloration functions.

Description

SYNTHETIC WOOD WITH ENHACED FLAME REFARDANCY AND BENDING STRENGTH AND MANUFACTURING METHOD THEREOF}

The present invention relates to a synthetic wood with improved flame retardancy and flexural strength, and to a method for manufacturing the same. The present invention relates to a synthetic wood having improved flame retardancy and bending strength so as to be used as an excellent interior material, and a method of manufacturing the same.

In general, natural wood is mainly used as exterior materials or interior materials of buildings such as floorboards, ceiling boards, doors, door frames, windows and fences.

Natural wood is mainly used as interior and exterior materials of buildings because the consumer's preference for wood and aesthetics due to natural texture are improved.

However, the interior and exterior materials of buildings made of natural wood are deteriorated by forest damage due to wood felling, water resistance, heat resistance, impact strength, flexural strength, dimensional stability, flame retardancy, weather resistance, and antibacterial properties due to the inherent properties of wood. It is difficult to use as an exterior material, and the life expectancy is shortened due to the deterioration of antimicrobial activity by wood materials, and the use of copper, arsenic, and chromium-based antiseptics (called CCA preservatives) for the purpose of strengthening the antimicrobial properties is mixed and used. .

In order to solve this problem, recently, synthetic wood having a texture and appearance similar to natural wood is widely used as an interior and exterior material of a building. The synthetic wood is a powder obtained by pulverizing fibers such as wood or crests, corn stalks, and pulp, The powder is made of a mixture of polyvinyl chloride (PVC) resin, which is a representative thermoplastic resin having excellent processability, and is manufactured and used as an interior and exterior material of a building by extrusion processing.

As related technologies, there have been disclosed various examples such as using starch and chaff, and combining PVC and wood flour, but preconfigured to facilitate extrusion.

However, these disclosed technologies have a limit of not adding more than 50% by weight of wood flour, which is difficult to export due to the failure to meet the European synthetic wood standards.

The carbonization point of wood powder is 175 ℃ and the ignition point is 200 ℃, whereas PVC or ABS resin is melted at 180 ~ 190 ℃ and PP or PE is melted at 190 ~ 210 ℃, so it is heated above 175 ℃ to melt the resin. When the carbon powder is carbonized and discolored, the strength is decreased, the smell is generated, and the carbon generated by the carbonization has a small molecular weight and is pushed to the edge of the mold during extrusion, thereby roughening the surface and lowering the extrusion speed to accelerate productivity decline. There are also disadvantages. For example, the current extrusion rate is only about 30 cm per minute.

Therefore, conventionally, in consideration of this point, a large amount of chaff, starch, and other ingredients are added to increase the carbonization point, and as a result, the amount of wood powder is reduced by that amount, and only about 30% by weight is added.

In addition, since the surface quality is not good, there is a disadvantage in that the post-processing is necessary to smooth and uniform the surface as well as to remove the discolored portion.

In order to improve this, Korean Patent No. 1001922 has been disclosed.

However, the configuration disclosed in the registered patent is not suitable for use as an interior decoration material or interior material because it has a disadvantage of emitting toxic gas together with black smoke, which is a characteristic of PVC, during combustion because it cannot increase flame retardancy.

In addition, the effect of preventing discoloration and odor by preventing carbonization of the wood powder when forming the product is excellent, but the compression strength is low, the unexpected disadvantages such as deformation caused by the bending strength and thermal expansion of the product is derived.

The present invention was created to solve this problem in view of the above-mentioned drawbacks of the prior art, it is possible to sufficiently melt the synthetic resin even when added to 50% by weight or more of the wood powder or cocoa powder and below the carbonization point, the bonding phase Without causing any problems, carbonization does not occur, so the extrusion speed can be increased, and the surface of the extruded products can be uniform and smooth to maintain high quality. The main purpose of the present invention is to provide an improved synthetic wood and a method for manufacturing the same, which are further solved by further adding ocher and impact modifier to improve flame retardancy and flexural strength newly derived as a problem while maintaining the configuration of Patent No. 1001922.

The present invention is a means for achieving the above object, the content (amount) is 5% or less, wood powder 50-70% by weight, synthetic resin 20-30% by weight, surfactant 2.5-7.5% by weight, loess 5-15% by weight , Extruded composition is composed of 2.5 to 7.5% by weight acrylic acid provides a synthetic wood with improved flame retardancy and flexural strength, characterized in that it has a non-carbonized, colorless function.

At this time, the synthetic resin is characterized in that any one selected from PVC, ABS, PET.

In addition, the present invention provides a method for producing a synthetic wood with improved flame retardancy and whip strength by using a mixture consisting of the composition and composition ratio described above; A primary step of sufficiently stirring for 10 minutes while maintaining 100 DEG C while mixing synthetic resin with acrylic acid as a surfactant and a thickener; While the mixture is being stirred in the first step, the mixture is stirred for 5 minutes while the wood powder or cocoa powder and ocher are added and the surfactant remains inside the inorganic wood powder or cocoa powder without breaking -OH. A secondary process of increasing the viscosity of the mixture while removing the oil component (wood gin); Tertiary process of introducing the mixture obtained in the secondary process into an extruder; It also provides a method for producing a synthetic wood with improved flame retardancy and bending strength; consisting of a fourth step of extruding the product mixture while maintaining the extruder at a temperature of 140 ~ 150 ℃.

According to the present invention, the use of wood powder or cocoa powder is added at least 50% by weight, so that no carbonization occurs, there is no discoloration, the strength is excellent, and the extrudability and the extrusion speed reach 1 m per minute, so that the productivity is maximized. In addition to the effect can be excellent in flame retardancy can be utilized as interior materials, interior decoration materials, and further improve the compressive strength when forming the product can be obtained to minimize the bending deformation.

Hereinafter, the present invention will be described in more detail with reference to a preferred embodiment of the present invention.

Synthetic wood according to the present invention can contain more than 50% by weight of wood powder or cocoa powder, unlike the existing, and does not carbonize while satisfies the European synthetic wood standard enough, has no discoloration, and has excellent surface quality, in addition to ocher and impact modifier By further including to achieve excellent flame retardancy and bending strength improvement can be utilized as interior materials, interior decoration materials.

More specifically, the synthetic wood according to the present invention, assuming that the water content (amount) 5% or less, 50 to 70% by weight of wood or cocoa powder, 20 to 30% by weight of synthetic resin, 2.5 to 7.5% by weight of surfactant, ocher powder 5 ~ 15% by weight, a composition composed of 2.5 to 7.5% by weight of acrylic acid as a thickener is made by extrusion molding.

At this time, the wood flour or cocoa powder should be added at least 50% by weight so as to meet the European standard, but it is preferably limited to the above range for the satisfactory balance with other components.

In particular, the main components for constituting the synthetic wood need not be limited to wood powder, and cocoa powder having similar properties may be used.

The synthetic resin may be polyvinyl chloride (PVC), acrylonitrile butadiene styrene (ABS), polyethylene terephthalate (PET), or the like, or wood flour or cocoa powder and the remaining components (especially due to the addition ratio of ocher and acrylic acid). The composition ratio is different, and therefore, considering the mixing ratio required for molding with flame retardancy / flexural strength improvement), and when the synthetic resin is added in less than 20% by weight, the binding to wood flour or cocoa powder is reduced, and 30% by weight If it exceeds, it should be limited to the above range because the tendency of synthetic resin, ie, plastic, becomes stronger than that of wood.

In addition, the surfactant is one of the important configuration, by lowering the temperature at which the synthetic resin and wood powder or cocoa powder is bonded to enable the extrusion even in the temperature range in which the wood powder or cocoa powder is not carbonized.

This increases the binding by removing the grease, resulting in an effect of lowering the melting point of the synthetic resin, for example, when added less than 2.5% by weight, the effect of lowering the temperature at which the synthetic resin and wood powder or cocoa powder is combined, 7.5% by weight If it is added in excess of the amount of the bond can be lowered and the strength may be reduced, so should be added in the above range.

In other words, in the present invention, unlike the conventional resin resin has started to adhere to the wood powder or cocoa powder at least a certain temperature, that is, at least 180 ℃, lower temperature by removing the oil contained in the wood powder or cocoa powder, that is 160 ~ 170 It was confirmed that the wood flour or cocoa powder began to stick to the synthetic resin even at the carbonization point of the wood flour (175 ℃), which was lower than the ℃, which resulted in the effect of lowering the melting point of the synthetic resin.

In addition, ocher powder should be added in 5 to 15% by weight.

At this time, the ocher constituting the ocher powder is a natural soil composed of silica and soil containing hydrous iron oxide and anhydrous iron oxide, as is well known, and has been used as a pigment since prehistoric times because of its strong hiding power.

The loess is composed of about 60% by weight of illite, 25% by weight of Ca, 15% by weight of components such as Mg K Fe, has a fine pores, very active ion exchange, and excellent water purification and purification, The excellent anion and far infrared emission effects have already been demonstrated.

In particular, when the ocher powder is soil, when the ocher powder is mixed with the synthetic resin and heated, the flame retardant performance is increased because the synthetic resin penetrates into the fine pores of the ocher and is fired in that state, which is the core of the present invention. In order to fully satisfy this, the loess should be added in an amount of 5 to 15% by weight as described above.

In other words, when the ocher is excessively added out of the range, it is hardly changed as it is baked, so that extrudability and processability are poor, and when it is commercialized, it has a disadvantage of being easily broken, and when a small amount is added, the desired flame retardancy cannot be achieved.

However, in order to prevent the weakening of impact resistance due to the addition of ocher, a thickener is added, and the thickener is preferably acrylic acid as described below.

That is, the thickener is a component added for the impact reinforcing function to prevent cracking, and in view of viscosity, acrylic acid should be limited to the above range.

At this time, the acrylic acid is the simplest unsaturated carboxylic acid containing a carboxylic acid and a vinyl group, which is used industrially by the carbonylation reaction of acetylene, and is used for increasing the viscosity to provide impact resistance.

In the present invention, the addition of acrylic acid in less than 2.5% by weight can not give viscosity to ocher, resulting in weakening of impact resistance, and when it is added in excess of 7.5% by weight, extrudeability is improved, but it impairs plastic processing of loess and adversely affects flame retardancy. It should be limited to the above range because it is crazy.

The synthetic wood of the present invention having such a composition is produced by the following method.

First, a primary process of sufficiently stirring for 10 minutes while maintaining 100 ° C. in a state where a synthetic resin, a surfactant and acrylic acid as a thickener are mixed is performed.

Unlike the first patent, the first step is to mix and agitate the synthetic resin, surfactant and thickener first, and the order was changed in consideration of the plastic processability of the loess, and was maintained at 100 ℃ to reduce the reaction time and induce an efficient reaction. .

In this state, while the mixture is being stirred in the continuous process following the primary process, the secondary process of further stirring for 5 minutes is carried out while adding wood powder or cocoa powder and loess at the above-mentioned composition ratio.

Then, the -OH is sufficiently reacted without breaking. In particular, the surfactant removes the oil component (wood dust) remaining inside the inorganic wood flour or cocoa powder, thereby improving the binding property and strength, Manufacturing time can be reduced.

At the same time, the loess and the synthetic resin react with the plastic processing, and the thickener acrylic acid reacts with it to increase the viscosity to keep these mixtures in an extrudable state.

Through this process, a third step of introducing the reacted mixture into the extruder while being sufficiently stirred is performed.

When the mixture is introduced into the extruder through the third process, a fourth process of extruding and commercializing the extruder while maintaining the temperature of 140 to 150 ° C. is performed for forming the product.

In this case, the extrusion temperature is maintained at 140 to 150 ° C during extrusion because the melting point of the resin is effectively lowered by the surfactant, so that sufficient extrusion is possible, and this temperature is the carbonization point of wood powder or cocoa powder. Since it is 175 ℃ or less, carbonization of wood powder or cocoa powder does not occur during extrusion, and thus no discoloration occurs, the strength does not deteriorate, the reverse increase, no burnt smell, and the surface needs to be uniform and smooth. You will not.

In addition, since carbonization does not occur, there is no generation of C, and thus the surface is not roughened, so the extrusion speed is increased.

In addition, the product thus prepared has excellent flame retardancy and impact resistance or bending strength, so that bending deformation does not easily occur, and thus may be utilized as interior materials and interior decoration materials.

[Example]

Hereinafter, examples will be described.

This embodiment was tested under the same conditions as the experimental conditions described in the prior art Patent Registration No. 1001922, but the characteristics will be different because the components and composition ratio is different, and the results will be described by focusing on this.

In order to check the characteristics of the synthetic wood according to the present invention, and to check whether the characteristics have a difference from the existing products, the invention materials 1, 2 and comparative materials 1, 2 were configured with the following composition.

At this time, the conventional wood was added to less than 30% by weight of wood powder, and the typical synthetic wood was added to the chaff added to lower the carbonization point.

division Wood powder Synthetic Resin (PVC) Surfactants ocher Acrylic acid Inventory 1 60 25 4 7 4 Inventory 2 62 24 3 8 3 Comparison 1 60 40 - - - Comparative material 2 70 30 - - -

(Wherein units are weight percent)

Prototype Inventive Materials 1 and 2 and Comparative Materials 1 and 2 were prepared by extrusion molding the composition having the composition shown in Table 1 through the above-described method.

Compared to manufactured prototypes and existing ones,

Existing products did not meet the European standards, carbonization did not occur due to chaff and other ingredients, but the surface was rough and uneven, it was confirmed that post-processing is necessary.

Inventive materials 1 and 2 satisfied all the conditions required by the present invention, and it was confirmed that sufficient strength and wood powder content were achieved without discoloration carbonization.

In addition, as a result of spinning the flame with a torch at 50 cm intervals, the initial ignition was delayed, and some burnout occurred from 15 minutes while igniting slowly without burning for 10 minutes with some soot occurring. At the end of the minute all burned down.

At this time, there was no phenomenon that the product was dropped or warped until completely burned out.

Through this, it was confirmed that the synthetic wood according to the present invention has a significant flame retardancy, it was found that the excellent compressive strength does not easily cause bending deformation.

In addition, the surface was smooth and glossy, so no additional post processing was required.

However, in the case of Comparative Materials 1 and 2, carbonization occurred because no surfactant was added, resulting in a decrease in strength, a burnt smell, and a rough surface and no gloss.

Through such experiments, the synthetic wood manufacturing method according to the present invention and the utilization of the synthetic wood produced by the method is expected to be very large, having a superior quality compared to the existing product, the price is low, and the extrusion speed is also excellent. It is expected to be very advantageous in terms of productivity.

Claims

Content rate (amount) is 5% or less,
50-70% by weight of wood flour,
20-30% by weight of synthetic resin,
2.5-7.5 wt% surfactant,
Ocher 5-15% by weight,
Composite wood with improved flame retardancy and flexural strength, characterized in that the composition composed of 2.5 to 7.5% by weight acrylic acid is extruded to have a non-carbonized, discolored function.

The method according to claim 1;
The synthetic resin is synthetic wood with improved flame retardancy and flexural strength, characterized in that any one selected from PVC, ABS, PET.

In the method for producing a synthetic wood with improved flame retardancy and whip strength by using the mixture consisting of the composition and the composition ratio of claim 1;
A primary step of sufficiently stirring for 10 minutes while maintaining 100 DEG C while mixing synthetic resin with acrylic acid as a surfactant and a thickener;
In the continuous process following the first step, while stirring the mixture for 5 minutes while adding the wood powder or cocoa powder and loess, the surfactant remains inside the inorganic wood powder or cocoa powder without breaking -OH. A secondary process of increasing the viscosity of the mixture while removing the oil component (wood gin);
Tertiary process of introducing the mixture obtained in the secondary process into an extruder;
The fourth step of extruding the product mixture while maintaining the extruder at a temperature of 140 ~ 150 ℃ to commercialize; Method of producing a composite wood, characterized in that the flame resistance and bending strength improved.