KR102397310B1 - Method for manufacturing of high expansion ratio polyurethane foam without solvent, and polyurethane foam using the same - Google Patents

Abstract

The present invention relates to a polyurethane foam manufacturing method and a polyurethane foam produced therethrough. More specifically, the present invention is characterized by providing a method for producing a highly expanded polyurethane foam excellent in appearance quality by controlling the temperature and pressure in the reactor without using a solvent.

Description

High-foaming polyurethane foam manufacturing method without solvent and polyurethane foam manufactured by the manufacturing method

The present invention relates to a polyurethane foam manufacturing method and a polyurethane foam produced therethrough. More specifically, the present invention compares the control sequence of temperature and pressure of the density of the supercritical fluid in the reactor without using a solvent to simplify the process and produce a high-foaming polyurethane foam with excellent appearance quality and cost reduction effect. It provides a way to do it.

Thermoplastic polyurethanes (TPUs) have been known for a long time. They are of industrial importance because of the known advantages of high quality mechanical properties and low cost of being thermoplastically processed.

TPU is synthesized from linear polyols, diisocyanates and chain extenders.

When producing polyurethane foam, the polyol, diisocyanate and chain extender are put into a reactor, and additives such as a foaming agent and catalyst are added and mixed to foam the thermoplastic polyurethane. In general, a lot of water is used as the foaming agent. do.

On the other hand, there is a case in which the polyurethane foam is prepared by synthesizing the polyol and diisocyanate as described above and injecting the thermoplastic polyurethane pellets prepared without foaming by treating the foaming agent with a solvent in a reactor or the like. In this case, in general, a surfactant and a dispersing agent are used together with the solvent, and when the polyurethane foam is manufactured in this way, it is difficult to obtain excellent appearance quality and there is a disadvantage of low foaming.

International Patent Publication No. 2007-082838 relates to an expanded thermoplastic polyurethane bead, a method for manufacturing the same, and application thereof, in which pelletized thermoplastic polyurethane particles are put into an autoclave together with water as a foaming agent and a solvent and stirred, followed by foaming and washing process A method of manufacturing an expanded thermoplastic polyurethane bead through and using the same is shown.

Korean Patent Application Laid-Open No. 10-2016-0124821 relates to expanded thermoplastic polyurethane beads, a manufacturing method and application thereof, and expanded thermoplastic polyurethane by injecting and stirring pelletized thermoplastic polyurethane particles into an autoclave together with a foaming agent and water. A method for preparing beads and using them to manufacture a molding is shown.

Looking at the prior patent documents, it can be confirmed that the pelletized thermoplastic polyurethane particles are put into the autoclave together with the solvent. However, the reported pelletized thermoplastic polyurethane particles have a disadvantage in that the solubility and diffusivity of the supercritical foaming agent to the thermoplastic polyurethane particles are poor by preparing the foaming agent under supercritical conditions together with a solvent and other additives, which is the surface of the bead. And problems such as wrinkles, cracks, pores, etc. occurred as causes of shrinkage and deformation of the molded foam product, which caused various problems in the appearance and molding process.

In addition, as a post-processing process such as washing was added, various problems such as a decrease in productivity and an increase in manufacturing cost due to an increase in the manufacturing cycle time occurred.

In addition, since the density of the supercritical fluid was compared only by temperature and pressure, there was a problem that could not be known about the difference in solubility and diffusivity with respect to the density of the same supercritical fluid according to the control sequence of temperature and pressure.

International Patent Publication No. 2007-082838 Korean Patent Publication No. 10-2016-0124821

An object of the present invention is to provide a polyurethane foam manufacturing method capable of foaming polyurethane raw materials without using solvents and additives.

An object of the present invention is to provide a method for producing a polyurethane foam through a reactor.

An object of the present invention is to provide a method for producing a polyurethane foam of high foaming by controlling the temperature and pressure.

An object of the present invention is to provide a method capable of maximally suppressing the change in density due to the shrinkage of the polyurethane foam after foaming.

The object of the present invention is not limited to the object mentioned above. The object of the present invention will become clearer from the following description, and will be realized by means and combinations thereof described in the claims.

According to the present invention, there is provided a polyurethane foam having a density of 100 to 320 kg/m 3 and having a homogeneous flexible surface.

The shore hardness of the polyurethane raw material, which is the raw material of the polyurethane foam, is 80 A to 96 A, and the melting point (T _m ) may be 120 to 150° C.

According to the present invention, the input step of introducing the polyurethane raw material into the reactor; a reaction step of reacting a polyurethane raw material by applying heat and pressure in the reactor; a constant temperature and constant pressure step of maintaining a constant temperature and pressure in the reactor; and foaming and curing the polyurethane raw material; provides a polyurethane foam manufacturing method comprising, in the reaction step, injecting carbon dioxide into the reactor and applying heat and pressure.

In the preparation step, the polyurethane raw material may be prepared into pellets by reacting a polyol compound and an isocyanate compound.

The polyol compound may include any one selected from the group consisting of ester polyols, ether polyols, carrolactone polyols, and combinations thereof.

The isocyanate compound may include any one selected from the group consisting of aromatic isocyanate, aliphatic isocyanate, and combinations thereof.

In the input step, the solvent and additives may not be added to the reactor.

The polyurethane raw material input to the reactor may be stirred at a speed of 10 to 500 rpm.

The reaction step may include a temperature raising step of raising the temperature in the reactor to a target value; and a pressure raising step of increasing the pressure in the batch reactor to a target value.

The reaction step may be to increase the temperature in the reactor to a target value and then to increase the pressure to the target value, or to increase the pressure in the reactor to the target value and then to increase the temperature to the target value.

In the reaction step, the target value for the carbon dioxide density by increasing the temperature and pressurizing the pressure may be 0.127 to 0.200 g/cm ³ .

In the temperature raising step, the target value for the temperature may be 50 to 200° C., and the target value for the pressure in the pressure increasing step may be 75 to 200 bar.

When the temperature and pressure reach the target values in the constant temperature and constant pressure step, the temperature and pressure may be maintained at the target values for 30 to 300 minutes.

In the foaming and curing step, the polyurethane raw material may be foamed into a desired shape and cured at room temperature.

In the foaming and curing step, the change in density of the cured polyurethane raw material based on the polyurethane raw material immediately after foaming may be 20% or less.

The carbon dioxide injected into the reactor in the reaction step may be in a supercritical fluid state.

The polyurethane foam may have a density of 0.100 g/cm 3 to 0.320 g/cm 3 and a homogeneous flexible surface.

The reactor may include a batch reactor.

According to the present invention, it is possible to provide a polyurethane foam manufacturing method capable of foaming a polyurethane raw material without using a solvent and additives.

According to the present invention, it is possible to provide a method for producing a polyurethane foam through a reactor.

According to the present invention, it is possible to provide a method for producing a polyurethane foam of high foaming by controlling the temperature and pressure.

According to the present invention, it is possible to provide a method capable of maximally suppressing the change in density due to the shrinkage of the polyurethane foam after foaming.

The effects of the present invention are not limited to the above-mentioned effects. It should be understood that the effects of the present invention include all effects that can be inferred from the following description.

1 shows a flow chart for the polyurethane foam manufacturing method of the present invention.
Figure 2 shows the appearance of the foam bead prepared in Example 1.
Figure 3 shows the cell morphology (Cell Morphology) of the foamed beads prepared in Example 1.
4 shows the appearance of the foamed beads prepared in Comparative Example 1.
Figure 5 shows the cell morphology (Cell Morphology) of the foamed beads prepared in Comparative Example 1.

The above objects, other objects, features and advantages of the present invention will be easily understood through the following preferred embodiments in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms. Rather, the embodiments introduced herein are provided so that the disclosed subject matter may be thorough and complete, and that the spirit of the present invention may be sufficiently conveyed to those skilled in the art.

In the present specification, terms such as “comprise” or “have” are intended to designate that a feature, number, step, operation, component, part, or combination thereof described in the specification exists, but one or more other features It is to be understood that it does not preclude the possibility of the presence or addition of numbers, steps, operations, components, parts, or combinations thereof. Also, when a part of a layer, film, region, plate, etc. is said to be “on” another part, it includes not only the case where the other part is “directly on” but also the case where there is another part in between. Conversely, when a part, such as a layer, film, region, plate, etc., is "under" another part, this includes not only cases where it is "directly under" another part, but also a case where another part is in the middle.

In this specification, where a range is described for a variable, the variable will be understood to include all values within the stated range including the recited endpoints of the range. For example, a range of “5 to 10” includes the values of 5, 6, 7, 8, 9, and 10, as well as any subranges such as 6 to 10, 7 to 10, 6 to 9, 7 to 9, etc. It will be understood to include any value between integers that are appropriate for the scope of the recited range, such as 5.5, 6.5, 7.5, 5.5 to 8.5 and 6.5 to 9, and the like. Also, for example, a range of "10% to 30%" includes values such as 10%, 11%, 12%, 13%, and all integers up to and including 30%, as well as 10% to 15%, 12%, etc. It will be understood to include any subranges such as from 18% to 18%, 20% to 30%, etc., as well as any value between reasonable integers within the scope of the recited ranges, such as 10.5%, 15.5%, 25.5%, and the like.

The present invention relates to a polyurethane foam manufacturing method and a polyurethane foam manufactured by the manufacturing method.

The present invention is characterized in that it provides a method for producing a highly expanded polyurethane foam excellent in appearance quality by controlling the temperature and pressure in the reactor without using a solvent and additives.

1 shows a flowchart related to the polyurethane foam manufacturing method of the present invention, and each step will be described in detail with reference to this.

The polyurethane foam manufacturing method of the present invention includes a preparation step of preparing a polyurethane raw material containing a polyol compound and an isocyanate, an input step of putting the prepared polyurethane raw material into a reactor (Autoclave Reactor), heat and pressure in the reactor It includes a reaction step of reacting the polyurethane raw material by adding it, and foaming and curing the polyurethane raw material.

preparatory stage

This is the stage of preparing the polyurethane raw material.

The polyurethane raw material of the present invention is characterized in that it is prepared in the form of pellets by reacting a polyol compound and an isocyanate compound.

The polyol compound of the present invention includes at least one polyol of polycaprolactone-based polyol, polycarbonate-based polyol, polyether-based polyol, and polyester-based polyol.

The polyol refers to an alcohol having three or more hydroxyl groups (-OH).

The isocyanate compound of the present invention includes at least one of an aromatic isocyanate and an aliphatic isocyanate.

The polyurethane raw material of the present invention is affected by the type of the isocyanate compound. When an isocyanate compound containing an aromatic isocyanate is reacted, an aromatic polyurethane raw material is prepared, and when an isocyanate compound containing an aliphatic isocyanate is reacted, aliphatic Polyurethane raw materials are manufactured. That is, the polyurethane raw material of the present invention is characterized in that it includes one raw material selected from the group consisting of an aromatic polyurethane raw material, an aliphatic polyurethane raw material, and a combination thereof.

The aromatic isocyanate includes one selected from the group consisting of toluene diisocyanate, diphenylmethane diisocyanate, phenylene diisocyanate, torylene diisocyanate, and combinations thereof.

The aliphatic isocyanate includes one selected from the group consisting of isophorone diisocyanate, cyclohexane diisocyanate, dicyclohexylmethane diisocyanate, hexamethylene diisocyanate, and combinations thereof.

In the present invention, the isocyanate compound preferably includes an aliphatic isocyanate.

The polyurethane preferably has a shore hardness of 80 A to 96 A, and a melting point (Tm) of 120° C. to 150° C.

In preparing the polyurethane raw material of the present invention, a chain extender may be used together with a polyol compound and an isocyanate compound.

The chain extender includes one selected from the group consisting of butanediol, monoethylene glycol, diethylene glycol, hexamethylene glycol, neopentyl glycol, dipropylene glycol, methylpentanediol, and combinations thereof.

input stage

It is a step of inputting the prepared polyurethane raw material into the reactor.

The reactor more specifically refers to an autoclave reactor, and the autoclave reactor has the characteristic of being able to stir the polyurethane raw material injected therein under high temperature and high pressure. At this time, the stirring is preferably performed at a speed of 10 to 500 rpm, and the stirring is continued until the polyurethane raw material is added and then the polyurethane raw material is foamed.

In the reactor, the inside of the reactor to which the polyurethane raw material is input is sealed from the outside, and is not affected by external temperature and pressure.

The reactor includes an impeller that rotates in conjunction with a motor disposed outside, and the impeller rotates to stir the polyurethane raw material introduced into the reactor. In the present invention, it is characterized in that other additives including solvents are not included in addition to the polyurethane raw material.

reaction step

It is a step of reacting the polyurethane raw material by applying heat and pressure in the reactor. Specifically, carbon dioxide (CO ₂ ) is injected into the reactor to stir the raw material. At this time, as heat and pressure are applied to the polyurethane raw material being stirred, the temperature and pressure in the reactor are increased to a predetermined target value.

The reaction step includes a temperature raising step of raising the temperature in the reactor to a target value, and a pressure increasing step of increasing the pressure in the reactor to a target value. The reaction step is characterized in that in more detail, the temperature in the reactor is raised to a target value and then the pressure is increased to the target value, or the pressure in the reactor is increased to the target value and then the temperature is increased to the target value.

In particular, the main feature is to stir and react the polyurethane raw material by converting the carbon dioxide injected into the reactor into a supercritical state. That is, the carbon dioxide injected with heat and pressure applied to the reactor is converted into carbon dioxide in a supercritical state by making the state above the critical temperature and the critical pressure.

Specifically, the density of carbon dioxide may be 0.127 to 0.200 g/cm ³ by increasing the temperature and pressure in the reactor. In this case, the carbon dioxide may be in a supercritical state. That is, in the present invention, carbon dioxide in a supercritical state having both liquid and gas characteristics serves as a solvent instead.

In general, the carbon dioxide has a critical temperature of about 31.1° C. and a critical pressure of about 73.8 bar, and in the present invention, heat above the critical temperature is applied to the carbon dioxide before inputting the carbon dioxide to the reactor and a pressure above the critical pressure is applied to make the carbon dioxide supercritical. make it state

The pressure in the reactor of the present invention may be controlled by the injected supercritical carbon dioxide, but it is more preferable that the heat is separately controlled by the reactor itself.

The reaction step of the present invention may be divided into temperature and pressure raising steps and constant temperature and constant pressure steps.

In the present invention, the target value for the temperature is preferably 50 to 200° C., and the target value for the pressure is preferably 75 to 200 bar.

constant temperature and pressure steps

When the temperature and pressure in the reactor reach the target values, it is a step in which the temperature and pressure are maintained for a certain period of time without further supply and exchange of heat and pressure. That is, when both the temperature and pressure reach the target values after converting the carbon dioxide in the reactor to the supercritical state, the state is maintained.

In this case, when the temperature and pressure reach the target values, the temperature and pressure may maintain the target values for 30 to 300 minutes.

Foaming and curing steps

It is a step of foaming a polyurethane raw material stirred for a certain time in a constant temperature and constant pressure environment into a desired shape and sufficiently curing it at room temperature. More specifically, the polyurethane raw material, which was dissolved, dispersed, and stirred by the supercritical fluid carbon dioxide and the impeller inside the reactor, enters the stage of cell growth and stabilization within a relatively early time.

The foamed polyurethane raw material is cured over time, and at this time, the density of the polyurethane raw material is changed.

The density of the cured polyurethane raw material is increased by 1.0% to 20.0% based on the density of the polyurethane raw material immediately after foaming.

polyurethane foam

The present invention is characterized in providing a polyurethane foam manufactured by the above manufacturing method.

The density of the polyurethane foam is 100 to 320 kg / ㎥.

The expansion ratio of the polyurethane foam may be 3.0 times to 11.0 times.

Hereinafter, the present invention will be described in more detail through specific examples. However, these examples are for illustrating the present invention, and the scope of the present invention is not limited thereto.

Example 1

The prepared polyurethane raw material was put into an autoclave reactor including an impeller rotating at 50 rpm. Thereafter, carbon dioxide was injected into the reactor to increase the temperature inside the reactor, and the pressure was increased while maintaining the temperature. After maintaining this state for 30 minutes, the polyurethane raw material was foamed and cured to prepare a polyurethane foam. The density of carbon dioxide in the supercritical fluid state at this time is shown in Table 1 below.

Examples 2 to 10

The polyurethane foams of Examples 2 to 10 were prepared in the same manner as in Example 1 under the conditions shown in Table 1 below, and the pressurization sequence for the target value of temperature and pressure for the target value of temperature was pressurized after the temperature rise. TnP and the elevated temperature after pressurization were denoted as PnT, respectively.

division Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Example 8 Example 9 Example
10 Raw material TPU TPU TPU TPU TPU TPU TPU TPU TPU TPU Supercritical CO ₂ * (g/cm ³ ) 0.194 0.181 0.181 0.181 0.188 0.200 0.127 0.140 0.151 0.162 menstruum*
(parts by weight) - - - - - - - - - - SDBS*
(parts by weight) - - - - - - - - - - TCP*
(parts by weight) - - - - - - - - - - agitation speed
(rpm) 50 100 100 200 200 200 300 300 300 500 Sequence TnP TnP TnP TnP TnP TnP TnP TnP TnP TnP Constant temperature and pressure holding time
(minute) 30 45 60 75 90 120 150 200 250 300 Supercritical CO ₂ (g/cm ³ ): Density of carbon dioxide in a supercritical state (carbon dioxide in a state exceeding critical temperature 31.1° C. and critical pressure 73.9 bar)
solvent: water
SDBS: Sodium Dodecylbenzenesulfonate
TCP: Tricalcium Phosphate

Comparative Example 1 ~ Comparative Example 8

Polyurethane foams of Comparative Examples 1 to 8 were prepared in the same manner as in Example 1 under the conditions shown in Table 2 below, and the pressurization sequence for the target value of temperature and pressure for the target value of temperature was pressurized after the temperature rise. TnP and the elevated temperature after pressurization were denoted as PnT, respectively.

Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Comparative Example 7 Comparative Example 8 Raw material TPU TPU TPU TPU TPU TPU TPU TPU Supercritical CO ₂ * (g/cm ³ ) 0.181 0.181 0.273 0.181 0.181 0.188 0.127 0.151 menstruum*
(parts by weight) 250 - 500 - 250 - - SDBS*
(parts by weight) 0.13 - - - - - 0.13 - TCP*
(parts by weight) 6.70 - - - - - 6.70 - agitation speed
(rpm) 100 100 200 200 200 200 300 300 Sequence TnP PnT TnP TnP PnT TnP TnP TnP Constant temperature and pressure holding time
(minute) 45 60 75 75 75 90 150 500 Supercritical CO ₂ (g/cm ³ ): Density of carbon dioxide in a supercritical state (carbon dioxide in a state exceeding critical temperature 31.1° C. and critical pressure 73.9 bar)
Solvent: Water (based on 100 parts by weight of raw material)
SDBS: Sodium Dodecylbenzenesulfonate (DKSH Korea Ltd., CAS 25155-30-0), Surfactant
TCP: Tricalcium Phosphate (Sigma-Aldrich, CAS 7758-87-4), dispersant

Experimental example

Polyurethane Foam Density Measurement: ASTM C20 - 00 (2015)

The density, density change, and appearance quality of the polyurethane raw materials of Examples 1 to 10 and Comparative Examples 1 to 8 were obtained as shown in Tables 3 and 4 below.

Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Example 8 Example 9 Example
10 Density immediately after foaming
(g/cm ³ ) 0.3143 0.1831 0.1658 0.1016 0.1122 0.1413 0.1338 0.1204 0.1663 0.1972 Density after foam stabilization
(g/cm ³ ) 0.3179 0.1891 0.1719 0.1191 0.1312 0.1562 0.1542 0.1336 0.1720 0.1998 Density change*
(%) 1.1 3.3 3.7 17.2 16.9 10.5 15.2 11.0 3.4 1.3 Appearance quality* 5 5 5 5 5 5 5 5 5 5 Density change:
((XY)/X)*100%
X = Density of polyurethane raw material immediately after foaming
Y = Density of cured polyurethane raw material

Appearance quality: The closer to 1 the ratio of Perpendicularity/Horizontality before/after foaming and before/after foaming of the quality of the visual evaluation (appearance state such as cracks of foamed beads), it was judged that the beads were in a uniform and stable state. (1 ~ 0.9, 0.89 ~ 0.75, 0.74 ~ 0.5, 0.49 ~ 0.25, 0.24 ~ 0.05), the quality of polyurethane foam manufactured by combining these two evaluation methods is high (5) / high (4) / medium ( 3)/Middle/Low(2)/Low(1) are divided into 5 categories, and the average value of these scores is recorded.

Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Comparative Example 7 Comparative Example 8 Density immediately after foaming
(g/cm ³ ) 0.2144 0.4221 0.2218 0.9662 0.4125 0.2252 0.2431 0.3852 Density after foam stabilization
(g/cm ³ ) 0.2528 0.5225 0.2619 0.9922 0.5402 0.2619 0.3212 0.4916 Density change*
(%) 17.9 23.7 18.1 2.7 31.0 16.3 32.1 27.6 Appearance quality* 3 One 3 4 One 2 2 4 Density change:
((XY)/X)*100%
X = Density of polyurethane raw material immediately after foaming
Y = Density of cured polyurethane raw material

Appearance quality: The closer to 1 the ratio of Perpendicularity/Horizontality before/after foaming and before/after foaming of the quality of the visual evaluation (appearance state such as cracks of foamed beads), it was judged that the beads were in a uniform and stable state. (1 ~ 0.9, 0.89 ~ 0.75, 0.74 ~ 0.5, 0.49 ~ 0.25, 0.24 ~ 0.05), the quality of polyurethane foam manufactured by combining these two evaluation methods is high (5) / high (4) / medium ( 3)/Middle/Low(2)/Low(1) are divided into 5 categories, and the average value of these scores is recorded.

Referring to the results of Tables 3 and 4, Examples 1 to 10 exhibited very good results while satisfying the maximum foaming ratio of 9.15 according to the respective target values of temperature and pressure, and also in appearance quality. However, Comparative Examples 1 to 8 showed the solubility and diffusivity of the raw material with respect to the density of the same supercritical carbon dioxide by varying the control sequence for each target value of temperature and pressure, In the case of using a solvent, the solubility and diffusivity of the raw material with respect to the density of the same supercritical carbon dioxide were compared and shown.

As a result, when comparing the solubility and diffusivity of raw materials with respect to the density of the same supercritical carbon dioxide by varying the control sequence for each target value of temperature and pressure, the maximum expansion ratios were 9.15 and 4.31, respectively, and the appearance was 5, 3 is shown. In addition, when the control sequence for each target value of temperature and pressure is varied and a solvent including a solvent and other additives is used, when comparing the solubility and diffusivity of the raw material with respect to the density of the same supercritical carbon dioxide, the foaming ratio is 1.09 to 4.31 was shown.

Figure 2 is a result of observing the appearance of the foamed beads prepared in Example 1, Figure 3 is the result of observing the cell morphology of the foamed beads produced in Example 1. Referring to this, it can be seen that the foam bead according to Example 1 has a stable appearance and cell shape.

Meanwhile, FIG. 4 is a result of observing the appearance of the foamed beads prepared in Comparative Example 1, and FIG. 5 is a result of observing the cell morphology of the foamed beads produced in Comparative Example 1. As shown in FIG. Referring to this, it can be seen that the foamed beads according to Comparative Example 1 have very bad appearance and cells.

Although non-limiting and exemplary embodiments of the present invention have been described above, the technical spirit of the present invention is not limited to the accompanying drawings or the above description. It is apparent to those of ordinary skill in the art that various types of modifications are possible within the scope of the present invention without departing from the spirit of the present invention, and it will be said that such modifications fall within the scope of the claims of the present invention.

Claims (17)

An input step of introducing a polyurethane raw material into the reactor;
a reaction step of reacting a polyurethane raw material by applying heat and pressure in the reactor;
a constant temperature and constant pressure step of maintaining a constant temperature and pressure in the reactor; and
Including; foaming and curing the polyurethane raw material;
Polyurethane foam manufacturing method, characterized in that by injecting carbon dioxide into the reactor in the reaction step and applying heat and pressure so that the density of the carbon dioxide is 0.127 to 0.200 g/cm ³ .
According to claim 1,
The polyurethane raw material has a shore hardness of 80 A to 96 A, and a melting point (Tm) of 120° C. to 150° C. The polyurethane foam manufacturing method.
According to claim 1,
In the preparation step, the polyurethane raw material is a polyurethane foam manufacturing method prepared by reacting a polyol compound and an isocyanate compound.
4. The method of claim 3,
The polyol compound is a polyurethane foam manufacturing method comprising any one selected from the group consisting of ester polyol, ether polyol, caprolactone polyol, and combinations thereof.
4. The method of claim 3,
The isocyanate compound is a polyurethane foam manufacturing method comprising any one selected from the group consisting of aromatic isocyanates, aliphatic isocyanates, and combinations thereof.
According to claim 1,
a solvent in the reactor in the input step; And a method for producing a polyurethane foam that the additive comprising at least one selected from the group consisting of surfactants, dispersants, and combinations thereof is not added.
According to claim 1,
A polyurethane foam manufacturing method in which the polyurethane raw material input to the reactor is stirred at a speed of 10 to 500 rpm.
According to claim 1,
The reaction step may include a temperature raising step of raising the temperature in the reactor to a target value; and
Polyurethane foam manufacturing method comprising a; a pressure raising step of raising the pressure in the reactor to a target value.
According to claim 1,
The reaction step is a method for producing a polyurethane foam to increase the temperature in the reactor to a target value and then to increase the pressure to the target value.
delete 9. The method of claim 8,
The temperature raising step is to increase the temperature of the reactor to 50 to 200 ℃,
The step of raising the pressure is a polyurethane foam manufacturing method to increase the pressure of the reactor to 75 to 200 bar.
8. The method of claim 7,
The constant temperature and constant pressure step is a polyurethane foam manufacturing method that is performed for 30 to 300 minutes.
According to claim 1,
A polyurethane foam manufacturing method that foams a polyurethane raw material into a desired shape in the foaming and curing step and curing it at room temperature.
According to claim 1,
A polyurethane foam manufacturing method in which the density change of the cured polyurethane raw material based on the polyurethane raw material immediately after foaming in the foaming and curing step is 20% or less.
According to claim 1,
Carbon dioxide injected into the reactor in the reaction step is a polyurethane foam manufacturing method in a supercritical fluid state.
According to claim 1,
The polyurethane foam has a density of 0.100 g/cm 3 to 0.320 g/cm 3 , and a polyurethane foam manufacturing method, characterized in that it has a homogeneous flexible surface.
According to claim 1,
The reactor is a polyurethane foam manufacturing method comprising a batch reactor.

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