A waterproof and breathable membrane for construction and a processing method thereof

Abstract

The application belongs to the technical field of textile production and relates to a processing method of a waterproof and breathable membrane for buildings, which comprises the following steps: flash spinning of a spinning solution, web laying of the flash spun yarn, hot pressing and calendering to obtain the waterproof and breathable membrane and by-product flash tail gas; the flash tail gas is heated in an oxidation furnace for more than 2 seconds at a temperature of more than 1200 DEG C to obtain crude tail gas; the crude tail gas is then introduced into a quench tower and cooled by a cooling pipe with graphite filler in the quench tower to obtain intermediate tail gas; and the intermediate tail gas is discharged after being absorbed by an absorption tower. The waterproof and breathable membrane for buildings prepared by the above technical solution has a grammage of 40 g / m 2 above, no leakage within 2 hours under the condition of 1000 mm water column, and a water vapor throughput of 1000 g / (m 2 ·24h) or more. The flash tail gas is subjected to high-temperature rapid oxidation to completely oxidize the flash tail gas without generating dioxin, and the intermediate tail gas is effectively and rapidly cooled.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of textile production, and relates to a high polymer waterproof material for building, in particular to a waterproof and breathable film for building and a processing method thereof. BACKGROUND

[0002] The waterproof and breathable film, also known as breathable paper, is a new type of high polymer waterproof material. In terms of manufacturing process, the waterproof and breathable film has much higher technical requirements than general waterproof materials. In terms of quality, the waterproof and breathable film also has functional characteristics that other waterproof materials do not have. The waterproof and breathable film is mainly applied to steel structure and wood structure buildings in the field of building. The working principle of the waterproof and breathable film is that, in the state of water vapor, water particles are very small, and can penetrate to the other side of the capillary according to the principle of capillary motion, so that the vapor transmission phenomenon occurs.

[0003] Some existing technical solutions for preparing non-woven fabric by using flash evaporation method make the high polymer re-solidify into fibers due to the rapid evaporation of the solvent. The dry spinning technology used in the flash evaporation method is different from the ordinary dry spinning, mainly in that the flash evaporation method uses lower spinning liquid viscosity and sprays from the spinneret at extremely high pressure and speed. Due to the low viscosity and good fluidity of the solution, the liquid yarn is solidified into an extremely fine fiber yarn in high-speed motion, and finally is directly formed into a fiber web on the webbing curtain. In the flash evaporation process, a large amount of solvent is volatilized to form a polluted tail gas, which will cause harm to the environment.

[0004] For example, the Chinese invention patent with the publication number CN112609334B discloses a flash evaporation non-woven fabric and a preparation method thereof. In the tail gas treatment, the solvent vapor generated by evaporation of the solvent is delivered to the lower section of the adsorption tower by a fan, the liquid adsorbent for adsorbing the solvent vapor is sprayed from the upper section of the adsorption tower and mixed with the solvent vapor in the adsorption tower, and after the adsorption is completed, the liquid is discharged from the bottom of the adsorption tower and the gas is discharged from the top of the adsorption tower.

[0005] Although the above technical solution uses liquid adsorbent to mix and adsorb the solvent vapor, the unadsorbed gas still needs to be discharged. SUMMARY

[0006] The purpose of the present application is to provide a waterproof and breathable film for building.

[0007] Another purpose of the present application is to provide a processing method of the waterproof and breathable film for building.

[0008] The processing method of the waterproof and breathable film for building creatively provided by the present application comprises the following steps:

[0009] The spinning solution is flash spun, and the flash spun solution is laid on a web, and a waterproof and breathable film and a by-product flash tail gas are obtained through heat pressing and calendering treatment;

[0010] The flash tail gas is heated in an oxidation furnace for more than 2 seconds at a temperature of more than 1200 DEG C to obtain a crude tail gas;

[0011] The crude tail gas is then introduced into a quench tower, and is cooled in a cooling pipe with graphite packing inside the quench tower to obtain an intermediate tail gas;

[0012] The intermediate tail gas is discharged after being absorbed by an absorption tower.

[0013] The flash tail gas is rapidly oxidized at a high temperature, so that it is completely oxidized and no dioxin is produced, and the intermediate tail gas is rapidly cooled by using graphite packing as the packing of the cooling pipe, so that the heat and mass transfer between gas and liquid is strengthened, and the outlet temperature is lower than 120 DEG C.

[0014] In the above method for processing a waterproof and breathable film for buildings, the filling amount of the graphite packing in the cooling pipe is more than 60% of the total volume of the cooling pipe.

[0015] By increasing the graphite packing to more than 60% of the total volume, the cooling efficiency of the cooling pipe for the intermediate tail gas is greatly improved, and the heat and mass transfer between gas and liquid is further strengthened.

[0016] In the above method for processing a waterproof and breathable film for buildings, the oxidation furnace has a U-shaped structure, and the top of the oxidation furnace is connected to the top of the quench tower, and the bottom of the quench tower is connected to the bottom of the absorption tower, so that the flow direction of the tail gas is in the shape of a Chinese character ''.

[0017] The oxidation furnace, the quench tower and the absorption tower form a '' Chinese character '' tail gas treatment channel, so as to ensure the residence time of the tail gas, reasonably utilize the space, and optimize the effect of tail gas treatment.

[0018] In the above method for processing a waterproof and breathable film for buildings, the quench tower and the absorption tower are respectively sprayed with an absorption liquid in the towers.

[0019] The absorption liquid is a warm liquid, and can be an alkali solution, such as a sodium hydroxide solution, which is used to neutralize hydrogen chloride gas in the waste gas.

[0020] In the processing method of the waterproof and breathable membrane for building, the polymer is dissolved in the spinning solvent to obtain the spinning solution, the polymer includes PE and / or PP, and the spinning solvent includes one or more than two kinds of mixture of dichloromethane, trichlorofluoromethane, 1,1-dichloro-2,2,2-trifluoroethane (HC-123), 1,2-dichloro-1,2,2-trifluoroethane (HC-123a), and 1,1-dichloro-2,2-difluoroethane (HC-132a).

[0021] In the processing method of the waterproof and breathable membrane for building, the mass fraction of the polymer in the spinning solution is 8% to 16%.

[0022] In the processing method of the waterproof and breathable membrane for building, the spinning temperature of the flash spinning is 200 to 220°C, the temperature of the heat pressing treatment is 110 to 115°C, and the temperature of the calendering treatment is 110 to 115°C.

[0023] By using the above components as the spinning solution components and by using the corresponding control conditions, the waterproof and breathable membrane with excellent waterproof and breathable performance can be prepared, the byproduct flash tail gas can be completely purified by using the tail gas treatment method of the application, and no secondary pollutants are generated.

[0024] The waterproof and breathable membrane for building prepared by the above technical solution further limits the grammage of the waterproof and breathable membrane to 40 g / m 2 or more under the condition of 1000 mm of water column, no leakage within 2 hours, and the water vapor transmission rate is 1000 g / (m 2 ·24h) or more.

[0025] In the waterproof and breathable membrane for building, the grammage of the waterproof and breathable membrane is further limited to 50 to 60 g / m 2 .

[0026] In the waterproof and breathable membrane for building, the grammage of the waterproof and breathable membrane is further limited to 60 to 70 g / m 2 .

[0027] In the waterproof and breathable membrane for building, the water vapor transmission rate of the waterproof and breathable membrane is 1000 to 2000 g / (m 2 ·24h).

[0028] In the waterproof and breathable membrane for building, the water vapor transmission rate of the waterproof and breathable membrane is 2000 to 3000 g / (m 2 ·24h).

[0029] The waterproof and breathable membrane can better adapt to the waterproof and breathable materials for steel structure and wood structure buildings.

[0030] Compared with the prior art, the application has the advantages that:

[0031] 1) The application adopts high-temperature rapid oxidation for flash tail gas, so that the flash tail gas is completely oxidized and no dioxin is produced, and graphite packing is used as the packing of the cooling pipe to effectively and rapidly cool the intermediate tail gas, to strengthen gas-liquid heat and mass transfer, and to absorb while cooling, so that the outlet temperature is lower than 120 DEG C.

[0032] 2) The application greatly improves the cooling efficiency of the cooling pipe for the intermediate tail gas by increasing the graphite packing to more than 60% of the total volume, further strengthens the gas-liquid heat and mass transfer, and improves the efficiency of tail gas treatment in cooperation with the oxidation furnace.

[0033] 3) The application uses specific components as the spinning solution components and corresponding control conditions to prepare a waterproof and breathable film with excellent waterproof and breathable performance, and the byproduct flash tail gas can be completely purified by the tail gas treatment method of the application, so that no secondary pollutants are produced, and sustainable development is realized.

[0034] 4) The waterproof and breathable film of the application can better adapt to the waterproof and breathable materials of steel structure and wood structure buildings. BRIEF DESCRIPTION OF DRAWINGS

[0035] Figure 1 is a tail gas treatment equipment schematic diagram in the waterproof and breathable film processing process of the application.

[0036] Figure 2 is a structure schematic diagram of a nozzle provided by the application.

[0037] Figure 3 is a structure schematic diagram of another nozzle provided by the application.

[0038] In the figure: oxidation furnace 1, quenching tower 2, graphite packing 201, cooling pipe 202, absorption tower 3, nozzle body 4, spinning solution inlet cavity 420, conical section 421, circular arc section 422, spinning port 430, and horn port 440. DETAILED DESCRIPTION

[0039] The application is further described through the following specific examples.

[0040] In the following description, many specific details are set forth in order to provide a thorough understanding of the application, but the application can also be practiced without the other ways different from those described herein, and therefore the application is not limited to the specific examples disclosed below.

[0041] Example 1

[0042] As Figure 1As shown, the tail gas treatment equipment in the building waterproof and breathable film processing process, the oxidation furnace 1 is U-shaped structure, the top of the oxidation furnace 1 and the top of the quenching tower 2 is connected, the bottom of the quenching tower 2 and the bottom of the absorption tower 3 is connected, the flow direction of the tail gas is "arch" shape.

[0043] The inner surface of the quenching tower 2 is coated with a layer of polytetrafluoroethylene resin. The inside of the quenching tower 2 is arranged with cooling pipes 202 in the longitudinal direction, and the cooling pipes 202 are filled with graphite filler 201 accounting for 60% of the total volume of the cooling pipes 202. The bottom of the quenching tower 2 contains a warm sodium hydroxide solution, the warm solution is 30-50℃, the warm sodium hydroxide solution is sprayed downward from the top and bottom of the cooling pipes 202 by a circulating pump, forming a tower internal spraying circulation of the quenching tower 2. The absorption tower 3 is provided with absorption filler, which is graphite filler, and the bottom of the absorption filler contains a sodium hydroxide solution. The warm sodium hydroxide solution is sprayed downward from the top of the absorption filler of the absorption tower by a circulating pump, forming a tower internal spraying circulation of the absorption tower 3.

[0044] The building waterproof and breathable film processing method comprises the following steps:

[0045] Step 1) PP is used as a polymer, dichloromethane is used as a spinning solvent to prepare a spinning solution, and the mass fraction of the polymer in the spinning solution is 8%. The spinning solution is subjected to flash spinning, and the spinning temperature of the flash spinning is 200℃. Then the flash spinning is subjected to webbing, heat pressing treatment at 110℃ and calendering treatment at 110℃ to obtain a waterproof and breathable film and a byproduct flash tail gas;

[0046] Step 2) the flash tail gas is introduced into the oxidation furnace 1 and heated for 2 seconds at a temperature of 1200℃ to obtain a crude tail gas;

[0047] Step 3) the crude tail gas is introduced into the quenching tower 2, the cooling liquid is circulated in the cooling pipes 202 with graphite filler 201 inside the quenching tower 2 to cool the crude tail gas and obtain an intermediate tail gas, and the hydrogen chloride gas is neutralized in the tower internal spraying circulation of the quenching tower 2;

[0048] Step 4) the intermediate tail gas is introduced into the absorption tower 3 through a pipeline and subjected to absorption treatment by the absorption filler, the hydrogen chloride gas is further neutralized in the tower internal spraying circulation of the absorption tower 3, and the dischargeable tail gas is obtained.

[0049] The obtained waterproof and breathable film has a grammage of 50g / m 2 The above, and under the condition of 1000mm water column, no leakage within 2 hours, the water vapor throughput is 1000g / (m 2 ·24h) or more.

[0050] Example 2

[0051] This example is the same as example 1, except that:

[0052] Step 2) heating temperature is 1250℃ to obtain the crude tail gas.

[0053] Example 3

[0054] This example is the same as Example 1, except that:

[0055] Step 2) heating temperature is 1300℃ to obtain the crude tail gas.

[0056] The nozzle used for spinning in the flash spinning process in the above Examples 1-3 is shown in Figure 2 The nozzle body 4 has a spinning solution inlet cavity 420 and a spinning orifice 430 axially opposite to each other, and the spinning solution inlet cavity 420 and the spinning orifice 430 communicate with each other through both ends of the nozzle body 4, the spinning solution inlet cavity 420 has a tapered section 421 with gradually decreasing diameter from outside to inside and a circular arc section 422 connected to the inner end of the tapered section 421, the inner end diameter of the spinning orifice 430 is smaller than the minimum diameter of the tapered section 421, and the inner end of the tapered section 421 and the inner end of the spinning orifice 430 are connected by the circular arc section 422. The outer end of the spinning orifice 430 is connected with a horn mouth 440 with gradually increasing diameter from inside to outside.

[0057] The included angle θ between the two side walls of the longitudinal section of the tapered section 421 is 15°. The included angle α between the two side walls of the longitudinal section of the horn mouth 440 is 85°.

[0058] The minimum diameter D1 of the tapered section 421 is 0.8 cm, the maximum diameter D2 of the tapered section 421 is 1.0 cm, the axial length L1 of the spinning solution inlet cavity 420 is 0.8 cm, the diameter D0 of the spinning orifice 430 is 0.16 cm, the axial length L2 of the spinning orifice 430 is 0.2 cm, and the axial length L3 of the horn mouth 440 is 0.35 cm.

[0059] Through this nozzle, a circular arc guiding structure can be set at the connection position of the spinning solution inlet cavity and the spinning orifice, avoiding dead angles and defects caused by debris and agglomeration under the condition of ensuring the spinning speed, so as to produce uniform breathable films and improve the air permeability of the breathable films.

[0060] Example 4

[0061] This example is the same as Example 1, except that:

[0062] The nozzle used for spinning in the flash spinning process is shown in Figure 3As shown, the nozzle body 4a has a spinning solution inlet cavity 420a and a spinneret 430a in the nozzle body 4a, the spinning solution inlet cavity 420a and the spinneret 430a are axially opposite and communicate with each other through both ends of the nozzle body 4a, the spinning solution inlet cavity 420a is a tapered section 421a with a gradually reduced diameter from outside to inside, the inner end diameter of the spinneret 430a is smaller than the minimum diameter of the tapered section 421a, and the inner end of the tapered section 421a is directly connected with the inner end of the spinneret 430a. The outer end of the spinneret 430a is connected with a horn mouth 440a with a gradually increased diameter from inside to outside.

[0063] The included angle θ between the two side walls of the longitudinal section of the tapered section 421a is 15°. The included angle α between the two side walls of the longitudinal section of the horn mouth 440a is 85°.

[0064] The maximum diameter D2 of the tapered section 421a is 1.0 cm, the axial length L1 of the spinning solution inlet cavity 420a is 0.8 cm, the diameter D0 of the spinneret 430a is 0.16 cm, the axial length L2 of the spinneret 430a is 0.2 cm, and the axial length L3 of the horn mouth 440a is 0.35 cm.

[0065] The breathable films prepared in Examples 1-4 were respectively used for water vapor transmission rate test.

[0066] Table 1 Product performance test table of examples

[0067]

[0068] The results show that the water vapor transmission rate of the breathable films prepared by using the nozzles of Examples 1-3 in the application is greatly improved compared with Example 4, indicating that the nozzles of Examples 1-3 in the application can achieve better air permeability.

[0069] Comparative Example 1

[0070] This comparative example is the same as Example 1, except that:

[0071] Step 2) heating temperature is 1100℃ to obtain a crude tail gas.

[0072] Comparative Example 2

[0073] This comparative example is the same as Example 1, except that:

[0074] Step 2) the flash tail gas is introduced into the oxidation furnace 1 and heated for 1 second.

[0075] Comparative Example 3

[0076] This comparative example is the same as Example 1, except that:

[0077] The cooling pipe 202 is filled with graphite filler 201 accounting for 50% of the total volume of the cooling pipe 202.

[0078] Table 2 tail gas test table at different heating temperatures

[0079]

[0080] The results show that the application can make the flash tail gas be completely oxidized by using 1200℃ or above and staying for 2s, and the DCM concentration, dioxin concentration and particulate matter concentration in the tail gas are greatly reduced.

[0081] Table 3 tail gas cooling effect test table at the inlet and outlet of the tail gas treatment equipment

[0082]

[0083] The results show that when the volume of graphite filler in the cooling pipe is higher than 60%, the cooling effect in the quench tower can be effectively improved.

[0084] The specific embodiments described herein are merely illustrative of the spirit of the application. Those skilled in the art of the present application can make various modifications or supplements to the described specific embodiments or use similar ways to replace, but will not deviate from the spirit of the application or exceed the scope defined by the appended claims.

[0085] Although the terms oxidation furnace 1, quench tower 2, graphite filler 201, cooling pipe 202, absorption tower 3, nozzle body 4, spinning solution inlet cavity 420, conical section 421, circular arc section 422, spinneret 430, horn 440 and the like are used more frequently herein. Use of these terms is merely to facilitate the description and explanation of the essence of the application, and any additional limitation resulting from their interpretation is contrary to the spirit of the application.

Claims

1. A waterproof, breathable film, characterized by, The waterproof and breathable film has a grammage of 40 g / m2 or more, no leakage within 2 hours under the condition of 1000 mm water column, and a water vapor transmission rate of 1000 g / (m2·24h) or more; The processing method of the waterproof and breathable film comprises the following steps: flash spinning a spinning solution, laying the flash spun solution, and obtaining a waterproof and breathable film and byproduct flash tail gas through heat pressing and calendering; the flash tail gas is introduced into an oxidation furnace (1) and heated for 2 seconds or more at a temperature of 1200 DEG C or more to obtain crude tail gas; the crude tail gas is introduced into a quenching tower (2) and cooled through a cooling pipe (202) with graphite filler (201) in the quenching tower (2) to obtain intermediate tail gas; the graphite filler (201) in the cooling pipe (202) has a filling amount of 60% or more of the total volume of the cooling pipe (202); and the intermediate tail gas is discharged after being absorbed by an absorption tower (3). The nozzle for jetting in the flash spinning process comprises a nozzle body (4), the nozzle body (4) has a spinning solution inlet cavity (420) and a jetting orifice (430), the spinning solution inlet cavity (420) and the jetting orifice (430) are axially opposite, the spinning solution inlet cavity (420) and the jetting orifice (430) are connected to each other and pass through both ends of the nozzle body (4), the spinning solution inlet cavity (420) has a tapered section (421) with a gradually decreasing diameter from outside to inside and a circular arc section (422) connected to the inner end of the tapered section (421), the inner end diameter of the jetting orifice (430) is smaller than the minimum diameter of the tapered section (421), and the inner end of the tapered section (421) and the inner end of the jetting orifice (430) are connected through the circular arc section (422), and the outer end of the jetting orifice (430) is connected with a horn (440) with an expanding diameter from inside to outside. The included angle θ between the two side walls of the longitudinal section of the tapered section (421) is 15°, and the included angle α between the two side walls of the longitudinal section of the horn (440) is 85°.

2. A waterproof, breathable film according to claim 1, wherein The waterproof and breathable film has a grammage of 50-60 g / m 2 .

3. A waterproof, breathable film according to claim 1, wherein The waterproof and breathable film has a grammage of 60-70 g / m 2 .

4. A waterproof, breathable film according to claim 1, wherein The waterproof and breathable film has a grammage of 70-80 g / m 2 .

5. A waterproof, breathable film according to claim 1, wherein The water vapor transmission rate of the waterproof and breathable film is 1000-2000 g / (m 2 ·24h).

6. A waterproof, breathable film according to claim 1, wherein The water vapor transmission rate of the waterproof and breathable film is 2000-3000 g / (m 2 ·24h).

7. A method of manufacturing a waterproof and breathable film according to any one of claims 1 to 6, wherein The processing method of the waterproof and breathable film comprises the following steps: The processing method of the waterproof and breathable film comprises the following steps: flash spinning a spinning solution, laying the flash spun solution, and obtaining a waterproof and breathable film and byproduct flash tail gas through heat pressing and calendering; the flash tail gas is introduced into an oxidation furnace (1) and heated for 2 seconds or more at a temperature of 1200 DEG C or more to obtain crude tail gas; the crude tail gas is introduced into a quenching tower (2) and cooled through a cooling pipe (202) with graphite filler (201) in the quenching tower (2) to obtain intermediate tail gas; the graphite filler (201) in the cooling pipe (202) has a filling amount of 60% or more of the total volume of the cooling pipe (202); and the intermediate tail gas is discharged after being absorbed by an absorption tower (3).

8. The method of manufacturing a waterproof and breathable film according to claim 7, wherein: The oxidation furnace (1) has a U-shaped structure, the top of the oxidation furnace (1) is connected with the top of the quenching tower (2), and the bottom of the quenching tower (2) is connected with the bottom of the absorption tower (3), so that the flow direction of the tail gas is in the shape of an "arch".

9. The method of manufacturing a waterproof and breathable film according to claim 7, wherein: The quenching tower (2) and the absorption tower (3) are respectively sprayed with absorption liquid in the towers.

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