KR102658444B1 - Polyester non-woven fabric for engineering works and method for fabricating the same - Google Patents

Abstract

The present invention is a polyester nonwoven fabric for civil engineering using recycled polyester, and relates to a nonwoven fabric for civil engineering with improved hygroscopicity and a method for manufacturing the same.

Description

Polyester nonwoven fabric for civil engineering with improved hygroscopicity and manufacturing method thereof {POLYESTER NON-WOVEN FABRIC FOR ENGINEERING WORKS AND METHOD FOR FABRICATING THE SAME}

The present invention relates to a nonwoven fabric for civil engineering with excellent water absorption effect and a method of manufacturing the same.

Non-woven fabric is made into a fabric by combining fibers with each other through mechanical treatment, moisture, and heat treatment to entangle the fibers using heat and resin without any processes such as spinning, weaving, or knitting. It is light, breathable, and durable. It has thermal insulation properties and the cut portion does not come loose.

Non-woven fabric can be manufactured using any raw material as long as it can be formed into a fibrous form. It can be manufactured from natural fibers, synthetic fibers, recycled fibers, inorganic fibers such as glass fiber, etc., and can be manufactured using short fibers as well as long fibers. It is also possible to produce.

These nonwoven fabrics are used in various fields such as clothing, industry, civil engineering, and agriculture, and the development of purpose-built nonwoven fabrics that satisfy appropriate physical properties for each application is also being actively developed.

Among these, nonwoven fabrics for civil engineering are widely used in civil engineering and construction sites to reinforce the bearing capacity of the ground and stabilize it by laying it on soft ground or slopes of structures.

Nonwoven fabric for civil engineering not only has a soil separation effect to prevent heterogeneous soils from mixing, and has excellent mechanical properties so that it is not easily destroyed, it also has the function of reinforcing the ground bearing capacity of the location where the nonwoven fabric is installed, as well as water permeability. It is excellent in allowing water to pass through and also has excellent drainage properties.

Republic of Korea Patent No. 1776399 relates to polyester nonwoven fabric for civil engineering and its manufacturing method. After spinning polyester polymer and stretching the filament through an ejector, the filament is opened by collision with a collision plate to form a web on a conveyor belt. In the method of manufacturing a polyester nonwoven fabric manufactured by imparting mechanical strength by heat compression or needle punching and providing dimensional stability by post-processing and calendar processing, the polyester polymer includes a masterbatch containing a UV stabilizer. A manufacturing method is disclosed in which a hydrophilic agent is applied to the surface after stretching the filament.

On the other hand, synthetic fibers such as polyester fibers have an overall hydrophobic structure, so there is a problem of low water absorption and generation of static electricity. When continuous use is repeated, the pores are blocked by soil, preventing water from draining, and the non-woven fabric There is a problem of water damage or softening of the soil under the non-woven fabric as it is kept as is. To solve this problem, a new non-woven fabric for civil engineering that has excellent moisture absorption and dries quickly so that it can be used continuously Development is needed.

Republic of Korea Patent Publication No. 2010-0129987

The purpose of the present invention is to provide a nonwoven fabric for civil engineering that satisfies the required excellent mechanical strength, excellent weather resistance, and excellent water permeability.

The purpose of the present invention is to provide a nonwoven fabric for civil engineering that has excellent water absorption, dries quickly and naturally, and maintains drainage and water permeability effects for a long time.

Another object of the present invention is to provide a nonwoven fabric for civil engineering that maintains excellent hygroscopicity despite rapid changes in external temperature and humidity while absorbing moisture.

In order to solve the above problems, the method for manufacturing polyester nonwoven fabric for civil engineering with improved hygroscopicity according to the present invention is,

a) mixing 100 parts by weight of recycled polyester and 20 to 50 parts by weight of non-recycled polyester;

b) dissolving 1 to 5 parts by weight of citric acid in 50 parts by weight of water;

c) immersing 10 to 20 parts by weight of microporous diatomaceous earth powder in the solution of step b) and then adding calcium carbonate at a molar ratio of 1/10 of the citric acid;

d) filtering the solution of c) to obtain microporous diatomaceous earth powder, washing it, and drying it;

e) mixing the powder obtained in step d) with 10 to 20 parts by weight of octylacrylate;

f) melting the mixture of step a) and adding the mixture obtained in step e);

g) cooling the mixed melt of step f) and then applying heat to melt-spun it to produce fiber yarn;

h) manufacturing the fiber yarn of step g) into a non-woven fabric;

Includes.

Specifically, in step g), the cooled mixed melt is cooled to a melt viscosity of 100 to 150 cPs, melted again at a temperature of 250 to 300 ° C, and spun at a spinning speed of 1,200 to 1,400 m/min. You can.

In the present invention, step h) includes the steps of h-1) opening the fiber yarn of step g); h-2) a hoppering step of blending and discharging the fiber yarn that has passed the step h-1); h-3) a carding step of forming the fiber yarn that has undergone step h-2) into a thinly spread web; h-4) a cross wrapping step of adjusting the thickness and width of the web; h-5) a needle punching step of repeatedly moving a needle plate with densely installed needles up and down on the upper part of the web; may be further included.

In the present invention, the microporous diatomaceous earth powder may have a size of 100 to 200 mesh, and the microporous diatomaceous earth powder may include fine pores with an average diameter of 1 to 5 μm (micrometer).

The present invention also provides a nonwoven fabric for civil engineering manufactured according to the above-described manufacturing method.

The nonwoven fabric for civil engineering according to the present invention has the effect of satisfying the required excellent mechanical strength, excellent weather resistance, and excellent water permeability.

The nonwoven fabric for civil engineering according to the present invention has excellent water absorption and dries naturally quickly, maintaining drainage and water permeability effects for a long time.

The nonwoven fabric for civil engineering according to the present invention has the effect of maintaining excellent hygroscopicity even in a rapid external temperature and humidity change while absorbing moisture.

Hereinafter, each configuration of the present invention will be described in more detail so that those skilled in the art can easily implement it. However, this is only an example, and the scope of rights of the present invention is determined by the following contents. Not limited.

As used herein, “preferred” or “preferably” refers to an embodiment of the invention that has certain advantages under certain conditions. However, other embodiments may also be preferred under the same or different conditions. Additionally, the identification of one or more preferred embodiments does not mean that other embodiments are not useful, nor does it exclude other embodiments that are within the scope of the invention.

As used herein, the term “comprising” is used to list materials, compositions, devices, and methods useful in the present invention and is not limited to the listed examples.

In particular, in the present invention, the term "comprising" refers to various states, such as a state in which the component is included as is, a state in which the component is processed as a precursor, a state in which the component is satisfied after processing, etc. It is not limited to the examples listed.

The present invention relates to a nonwoven fabric for civil engineering with improved hygroscopicity and a method of manufacturing the same. It satisfies the basic functions such as mechanical properties, weather resistance, water permeability, and drainage required for a nonwoven fabric for civil engineering, and has improved hygroscopicity, allowing moisture to be absorbed quickly. It has absorbent and fast-drying properties, allowing it to maintain excellent hygroscopicity for a long time.

Specifically, the method for manufacturing nonwoven fabric for civil engineering according to the present invention is,

a) mixing 100 parts by weight of recycled polyester and 20 to 50 parts by weight of non-recycled polyester;

b) dissolving 1 to 5 parts by weight of citric acid in 50 parts by weight of water;

c) immersing 10 to 20 parts by weight of microporous diatomaceous earth powder in the solution of step b) and then adding calcium carbonate at a molar ratio of 1/10 of the citric acid;

d) filtering the solution of c) to obtain microporous diatomaceous earth powder, washing it, and drying it;

e) mixing the powder obtained in step d) with 10 to 20 parts by weight of octylacrylate;

f) melting the mixture of step a) and adding the mixture obtained in step e);

g) cooling the mixed melt of step f) and then applying heat to melt-spun it to produce fiber yarn;

h) manufacturing the fiber yarn of step g) into a non-woven fabric;

Includes.

Below, each step and configuration of the present invention will be described in more detail.

Step a) is a step of mixing polyester raw materials, and is a step of mixing recycled polyester raw materials and non-recycled polyester raw materials.

The recycled polyester is used using recycled materials, rather than newly synthesized polyester raw materials. By utilizing these recycled materials, polyester nonwoven fabric with excellent environmental friendliness can be manufactured.

The non-recycled polyester is obtained through new synthesis, meaning that it is not recycled polyester. In the present invention, while increasing the content of recycled polyester, it satisfies physical properties suitable for civil engineering purposes and has the effect of improved water absorption.

If the content of non-recycled polyester is excessive than the above content, there is a problem that eco-friendliness is lowered and the manufacturing cost increases. Moreover, even though the manufacturing cost increases, in the case of the present invention, there is no significant difference in the effect, so it is suitable to use it in the above ratio.

Step b) is a step for preparing an additive, and is prepared as an aqueous solution by dissolving water in citric acid. The temperature of the water is not particularly limited, but is preferably around 10 to 20°C. The content of citric acid may be more than this, but if citric acid is added excessively compared to the amount participating in the actual reaction, the amount of discarded material increases, so it is preferable to add it within the above content range, and more than the above content. In small cases, calcium salt precipitation by salting-out reaction does not sufficiently occur within the micropores of the microporous diatomaceous earth powder, which will be described later, and as a result, there is a disadvantage in that a porous filler that fills the inside of the pores is not sufficiently formed. In other words, there is a problem that it is difficult to form ultrafine pores.

Step c) is a step of immersing 10 to 20 parts by weight of microporous diatomaceous earth powder in the aqueous solution of step b), wherein the microporous diatomaceous earth powder has a size of 50 to 100 mesh, and the microporous diatomaceous earth powder has an average diameter of 10. It may contain micropores of between 12 ㎛ (micrometer).

Through the process of immersing in the citric acid aqueous solution described above, the citric acid aqueous solution penetrates into the pores, and calcium salt precipitates are formed within the pores by the subsequent addition reaction of calcium carbonate.

The precipitate has moisture control properties, but is coarse due to its low citric acid content, and forms a precipitate inside the pores in the form of ultrafine pores, thereby making the polyester fiber yarn itself hygroscopic.

Ultrafine pores divide water molecules and store them within the ultrafine pores so that water can be absorbed and then re-released into the air, so water is absorbed quickly and evaporation and release of water molecules into the air occur quickly.

At this time, the content of calcium carbonate is added at a molar ratio of 1/10 of citric acid. That is, when 10 moles of citric acid are added based on the molar ratio, calcium carbonate can be added at a ratio of 1 mole.

After step c), the reacted microporous diatomaceous earth powder is obtained, washed, and dried to obtain microporous diatomaceous earth powder with ultrafine pores formed.

Then, in step e), the powder is mixed with 10 to 20 parts by weight of octylacrylate to form a polymer mixture, and this is added during the process of melting the mixture prepared in step a) and mixed so that it is uniformly mixed. By mixing during the melting process, it ensures uniform mixing throughout the melt.

Subsequently, the melt is cooled in step g), and then heated again to produce fiber yarn by melt spinning. Specifically, it is cooled to a melt viscosity of 100 to 150 cPs, and then again heated to a temperature of 250 to 300°C. It is melted again and spun at a spinning speed of 1,200 to 1,400 m/min.

The reason for limiting the melt viscosity is to prevent the polyester melt from clogging the ultrafine pores of the microporous diatomaceous earth powder in which the ultrafine pores are formed, and to prevent further melting and lowering of the viscosity.

After cooling is stopped in this state, fiber yarn is manufactured by spinning with a melt spinning machine.

The produced fiber yarn is made into a non-woven fabric in step h).

Specifically, h-1) opening the fiber yarn of step g), h-2) hoppering step of blending and discharging the fiber yarn that has passed step h-1), h-3) step of h-3) -2) a carding step of forming the processed fiber yarn into a thinly spread web, h-4) a cross wrapping step of controlling the thickness and width of the web, h-5) a needle plate on which needles are installed closely. It is manufactured as a non-woven fabric containing a three-dimensional structure by further including a needle punching step of repeatedly moving up and down on the top of the web.

The strength of needle-punched nonwoven fabrics is determined not by chemical adhesion between fibers, but by the frictional resistance of parallelized fibers and the entanglement of fibers arranged in the vertical direction during the needling process. Most needle-punched nonwoven fabrics undergo post-processing to improve their strength and properties.

What greatly affects the permeability of nonwoven fabrics is the weight per unit area of the fabric, but in needle-punched nonwoven fabrics, this changes depending on the density and thickness of the web due to needling during the manufacturing process. The structure and physical properties of needle-punched non-woven fabrics show significant differences in the non-woven fabrics produced depending on the raw material fiber characteristics, web manufacturing conditions in carding, type of needle punching fabric, and process factors, so they are used as civil engineering non-woven fabrics for each purpose as needed. It is desirable to process it to a level suitable for it.

The process of step h) of processing the fiber yarn may refer to prior art regarding nonwoven fabric manufacturing technology.

Hereinafter, the present invention will be described in more detail based on examples, but this is only an exemplary description for understanding the present invention, and the scope of the present invention is not limited or restricted to the following examples.

<Example 1>

a) 100 parts by weight of recycled polyester and 30 parts by weight of non-recycled polyester were mixed.

b) 3 parts by weight of citric acid were dissolved in 50 parts by weight of water.

c) After 12 parts by weight of microporous diatomaceous earth powder was immersed in the solution of step b), calcium carbonate was added at a molar ratio of 1/10 of the citric acid.

d) The solution in c) was filtered to obtain microporous diatomaceous earth powder, which was washed and dried.

e) The powder obtained in step d) was mixed with 13 parts by weight of octylacrylate.

f) The mixture obtained in step a) was melted and the mixture obtained in step e) was added.

g) After cooling the mixed melt in step f), it was cooled to a melt viscosity of 100 cPs, and then melted again at a temperature of 300° C. and spun at a spinning speed of 1,250 m/min to prepare a fiber yarn.

h) The fiber yarn of step g) above was made into a nonwoven fabric with a width of 0.9 m and a weight of 150 g/m ³ .

<Comparative Example 1>

Produced in the same manner as Example 1, except that the fiber yarn was mixed with 100 parts by weight of recycled polyester, 30 parts by weight of non-recycled polyester, and 12 parts by weight of unprocessed microporous diatomaceous earth powder. did.

<Comparative Example 2>

A commercially available recycled polyester nonwoven fabric for civil engineering was prepared.

<Comparative Example 3>

In Example 1, instead of performing step g), the mixed melt was melted as is at a temperature of 300°C and spun at a spinning speed of 1,250 m/min.

[Experimental method]

1. Tensile strength and elongation

Tensile strength and elongation were measured according to KS K 2630:2018.

2. Hygroscopicity evaluation

After cutting each nonwoven fabric specimen into 50*50cm, water was filled to a height of 1cm in a water tank with an area of 60*60cm, and the nonwoven fabric specimen was placed there.

The specimen was taken out and evaluated as follows according to the amount of water remaining in the water tank.

(◎: almost no water remains in the tank, ○: water remains throughout the tank, △: water remains at a height of less than 0.5 cm, water remains at a height of less than ×0.5 to 1 cm).

3. Evaluation of maintenance of moisture absorption effect

The specimen of 2 above was taken out and left hanging for 30 minutes to allow water to drain, and then the experiment of 2 above was repeated.

Tensile strength (kg/in) Tensile elongation (%) Hygroscopicity evaluation Evaluation of maintenance of moisture absorption effect Example 1 55 75 ◎ ◎ Comparative Example 1 38 51 O X Comparative Example 2 42 60 △ X Comparative Example 3 48 62 X X

Referring to Table 1 above, it can be seen that both Example 1 and Comparative Examples 2 and 3 have excellent tensile strength and tensile elongation.

However, in the case of Comparative Examples 2 and 3, it can be confirmed that the hygroscopicity and moisture absorption retention effect are poor, and it can be confirmed that the nonwoven fabric for civil engineering according to the present invention satisfies the mechanical properties and is excellent in hygroscopicity and moisture absorption retention effect.

Claims (5)

A method for manufacturing polyester nonwoven fabric for civil engineering with improved hygroscopicity,
a) mixing 100 parts by weight of recycled polyester and 20 to 50 parts by weight of non-recycled polyester;
b) dissolving 1 to 5 parts by weight of citric acid in 50 parts by weight of water;
c) immersing 10 to 20 parts by weight of microporous diatomaceous earth powder in the solution of step b) and then adding calcium carbonate at a molar ratio of 1/10 of the citric acid;
d) filtering the solution of c) to obtain microporous diatomaceous earth powder, washing it, and drying it;
e) mixing the powder obtained in step d) with 10 to 20 parts by weight of octylacrylate;
f) melting the mixture of step a) and adding the mixture obtained in step e);
g) cooling the mixed melt of step f) and then applying heat to melt-spun it to produce fiber yarn;
h) manufacturing the fiber yarn of step g) into a non-woven fabric;
A method of manufacturing a nonwoven fabric for civil engineering comprising a. According to paragraph 1,
In step g), the cooled mixed melt is cooled to a melt viscosity of 100 to 150 cPs, melted again at a temperature of 250 to 300 ° C, and spun at a spinning speed of 1200 to 1,400 m / min. Manufacturing method of nonwoven fabric.
According to paragraph 1,
In step h),
h-1) opening the fiber yarn of step g);
h-2) a hoppering step of blending and discharging the fiber yarn that has passed the step h-1);
h-3) a carding step of forming the fiber yarn that has undergone step h-2) into a thinly spread web;
h-4) a cross wrapping step of adjusting the thickness and width of the web;
h-5) a needle punching step of repeatedly moving a needle plate with densely installed needles up and down on the upper part of the web;
A method of manufacturing a nonwoven fabric for civil engineering, further comprising:
According to paragraph 1,
The microporous diatomaceous earth powder has a size of 50 to 100 mesh,
A method of producing a nonwoven fabric for civil engineering, characterized in that the microporous diatomaceous earth powder contains micropores with an average diameter of 10 to 12 ㎛ (micrometers).
Nonwoven fabric for civil engineering manufactured according to paragraph 1.