PVB low-frequency sound insulation film for laminated glass and preparation method thereof

Abstract

The present application provides a PVB low-frequency sound insulation film for laminated glass and a preparation method thereof, the preparation method comprising the following steps: a) dispersing multi-walled carbon nanotubes in an organic solvent to obtain a suspension solution; b) dissolving a piezoelectric polymer in the suspension solution obtained in step a) to obtain an electrospinning solution; c) electrospinning the electrospinning solution obtained in step b) by using the roller in the middle of a three-roller calender as a spinning receiver, while two PVB films enter through the upper and lower rollers of the three-roller calender, and the electrostatic fiber film is sandwiched between the PVB films through the pressing action of the heating rollers of the three-roller calender to obtain a PVB low-frequency sound insulation film for laminated glass. The preparation method prepares piezoelectric fibers through an electrospinning process, and then the fibers are compounded with PVB films through hot pressing to obtain piezoelectric fiber reinforced PVB films. The low-frequency sound insulation performance of the material is significantly improved, and the material is especially suitable for PVB low-frequency sound insulation films for laminated glass.

Description

Technical Field

[0001] This invention relates to the field of PVB technology, specifically to a PVB low-frequency sound insulation film for laminated glass and its preparation method. Background Technology

[0002] Polyvinyl butyral resin (PVB) film, also known as PVB film, is a plasticized film based on PVB resin. Due to its excellent properties such as transparency, heat resistance, sound insulation, flexibility, and good adhesion to glass, it is widely used in automotive glass, high-rise buildings, military industry, and daily life.

[0003] With the progress and development of modern society, noise pollution from various sources such as agriculture, industry, and transportation has been listed as one of the world's four major pollutions, alongside air pollution, water pollution, and solid waste pollution. According to a report by the World Health Organization, noise pollution is one of the most serious environmental hazards, causing hearing loss, sleep disorders, and other symptoms. PVB laminated glass is made by placing a PVB film between two or more glass substrates through a hot-pressing process. The presence of the polymer interlayer greatly improves the material's toughness and resilience. PVB is a damping material; its long polymer chains are prone to curling and entanglement. Under the influence of sound waves, the chain segments in the molecules move and slip, generating internal friction, converting sound energy into heat energy. However, similar to other traditional materials, its performance improvement is concentrated in the mid-to-high frequency range, while its blocking effect on some low-frequency noises, such as human voices, is not ideal. Therefore, improving its low-frequency sound insulation performance is a major challenge. Summary of the Invention

[0004] To address the problems existing in the prior art, the present invention provides a method for preparing a PVB low-frequency sound insulation film for laminated glass, the purpose of which is to obtain a PVB low-frequency sound insulation film with excellent low-frequency sound insulation performance, good transmittance, and safety and reliability.

[0005] This invention provides a method for preparing a PVB low-frequency sound-insulating film for laminated glass, comprising the following steps:

[0006] a) Disperse multi-walled carbon nanotubes in an organic solvent to obtain a suspension;

[0007] b) Dissolve the piezoelectric polymer in the suspension obtained in step a) to obtain an electrospinning solution;

[0008] c) Using the middle roller of the three-roll calender as a spinning receiver, the electrospinning solution obtained in step b) is electrospinned. At the same time, two PVB films are fed into the three-roll calender through the upper and lower rollers. Through the heating and pressing action of the three-roll calender, the electrostatic fiber film is sandwiched in the middle of the PVB film to obtain a PVB low-frequency sound insulation film for laminated glass.

[0009] Preferably, the organic solvent mentioned in step a) is one or more of dimethylformamide, dimethylacetamide, dimethyl sulfoxide, benzene, phenol, toluene, tetrahydrofuran, acetone, formic acid, acetic acid, hexafluoroisopropanol, dichloromethane, and chloroform.

[0010] Preferably, the piezoelectric polymer described in step b) is selected from one or more of polyvinyl chloride, polyvinyl fluoride, polyvinylidene fluoride, polymethyl methacrylate, and polyacrylonitrile.

[0011] Preferably, the polymer mass fraction of the electrospinning solution in step b) is 5% to 30%.

[0012] Preferably, the mass fraction of multi-walled carbon nanotubes in the electrospinning solution described in step b) is 0.01% to 1.5%.

[0013] Preferably, the electrospinning process described in step c) uses a spinneret with an inner diameter of 0.1 mm to 1.0 mm and a distance of 5 cm to 30 cm between the tip and the collecting device.

[0014] Preferably, the electric field strength of the electrospinning in step c) is 5kV~30kV, and the propulsion rate of the micro-injection pump is 0.05mL / h to 1.50mL / h.

[0015] Preferably, the hot pressing temperature in step c) is 50℃~150℃, the roller linear speed is 2m / min~10m / min, and the roller spacing is 0.1mm~1.5mm.

[0016] The present invention also provides a PVB low-frequency sound insulation film for laminated glass, which is prepared by the preparation method described in the above technical solution.

[0017] This paper provides a PVB low-frequency sound insulation film for laminated glass and its preparation method. The preparation method includes the following steps: a) dispersing multi-walled carbon nanotubes in an organic solvent to obtain a suspension; b) dissolving a piezoelectric polymer in the suspension obtained in step a) to obtain an electrospinning solution; c) using the middle roller of a three-roll calender as a spinning receiver, electrospinning the electrospinning solution obtained in step b) while two PVB films are fed through the upper and lower rollers of the three-roll calender. Through the heating and pressing action of the three-roll calender, the electrostatic fiber film is sandwiched between the PVB films to obtain a PVB low-frequency sound insulation film for laminated glass. This preparation method obtains piezoelectric fibers through electrospinning, and then composites the fibers with a PVB film through hot pressing to obtain a piezoelectric fiber-reinforced PVB film. The low-frequency sound insulation performance of this material is significantly improved, making it particularly suitable for PVB low-frequency sound insulation films for laminated glass.

[0018] The advantages of this invention are:

[0019] 1. The PVB film produced by this invention has only three layers, excellent low-frequency sound insulation performance, and is safe and reliable. The low-frequency sound insulation of the PVB film produced is improved by 3dB.

[0020] 2. The raw material system of the PVB low-frequency sound insulation film of the present invention is simple. Only a small amount of piezoelectric fiber needs to be added, and no nanomaterials need to be added, thus maintaining the light transmittance and mechanical properties of the product.

[0021] 3. The synthesis process of the PVB low-frequency sound insulation film of the present invention is simple, requiring only hot pressing and lamination using a common three-roll calender, making it suitable for industrial production. Attached Figure Description

[0022] Figure 1 A schematic diagram of the electrospinning experimental device and its process flow provided in an embodiment of the present invention;

[0023] Figure 2 A flowchart illustrating the preparation process of a PVB low-frequency sound insulation film for laminated glass provided in an embodiment of the present invention;

[0024] Figure 3 This is a scanning electron microscope image of the fiber morphology in Example 4 of the present invention;

[0025] Figure 4 The output voltage of the piezoelectric fiber in Embodiment 4 of the present invention;

[0026] Figure 5 This is a sound insulation characteristic curve of the piezoelectric fiber reinforced PVB film in Embodiment 4 of the present invention;

[0027] Figure 6 The transmittance results are for the laminated glass in Example 4 of this invention;

[0028] Figure 7The impact resistance results of the laminated glass in Embodiment 4 of the present invention; Implementation

[0029] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0030] This invention provides a method for preparing a PVB low-frequency sound-insulating film for laminated glass, comprising the following steps:

[0031] a) Disperse multi-walled carbon nanotubes in an organic solvent to obtain a suspension;

[0032] b) Dissolve the piezoelectric polymer in the suspension obtained in step a) to obtain an electrospinning solution;

[0033] c) Using the middle roller of the three-roll calender as a spinning receiver, the electrospinning solution obtained in step b) is electrospinned. At the same time, two PVB films are fed into the three-roll calender through the upper and lower rollers. Through the heating and pressing action of the three-roll calender, the electrostatic fiber film is sandwiched in the middle of the PVB film to obtain a PVB low-frequency sound insulation film for laminated glass.

[0034] This invention first disperses multi-walled carbon nanotubes in an organic solvent to obtain a suspension. In this invention, the organic solvent used is preferably selected from one or more of dimethylformamide, dimethylacetamide, dimethyl sulfoxide, benzene, phenol, toluene, tetrahydrofuran, acetone, formic acid, acetic acid, hexafluoroisopropanol, dichloromethane, and chloroform. In a preferred embodiment of this invention, the organic solvent is a mixture of dimethylformamide (DMF) and acetone (ACE); the volume ratio of DMF to ACE is preferably (1~5):1. This invention does not have any special restrictions on the source of the organic solvent; commercially available products of the above-mentioned organic solvents well known to those skilled in the art can be used.

[0035] In this invention, there are no special requirements for the source of the multi-walled carbon nanotubes; commercially available carbon nanotubes known to those skilled in the art can be used.

[0036] In this invention, a piezoelectric polymer is dissolved in the suspension prepared above to obtain an electrospinning solution. The piezoelectric polymer is preferably selected from one or more of polyvinyl chloride, polyvinyl fluoride, polyvinylidene fluoride, polymethyl methacrylate, and polyacrylonitrile. This invention does not impose any special restrictions on the source of the piezoelectric polymer; commercially available products of the aforementioned polymers well known to those skilled in the art can be used.

[0037] The present invention does not impose any special limitations on the dispersion and dissolution; magnetic stirring and ultrasonic dispersion techniques known to those skilled in the art can be used.

[0038] In this invention, the mass fraction of the electrospinning solution is preferably 5wt% to 30wt%, more preferably 5wt% to 20wt%.

[0039] After obtaining the electrospinning solution, this invention utilizes the middle roller of a three-roll calender as a spinning receiver to electrospin the obtained electrospinning solution. In this invention, the dimensions of the roller of the three-roll calender are 945mm*780mm*1455mm.

[0040] In this invention, electrospinning is a simple and effective method for preparing nanofiber membrane materials. It mainly utilizes polymer solutions or melts under the action of a strong electric field to spray and stretch them through a metal nozzle to obtain fibers with diameters ranging from tens of nanometers to several micrometers. The nanofiber membranes obtained by electrospinning generally have a certain porosity, continuous fibers, and adjustable diameter.

[0041] A schematic diagram of the electrospinning experimental device and process flow provided by this invention is shown below. Figure 1 As shown; where ① is a micro-injection pump, ② is a metal nozzle, ③ is a collection device, and ④ is a high-voltage power supply; the syringe used can be a 5mL medical syringe well known to those skilled in the art. In this invention, the inner diameter of the spinneret used in the electrospinning process is preferably 0.1mm~1.0mm; the distance between the tip of the spinneret and the collection device is preferably 5cm~30cm.

[0042] In this invention, the electric field strength of the electrospinning is preferably 5kV~30kV; the propulsion rate of the electrospinning solution is preferably 0.05mL / h~1.50mL / h; and the electrospinning time is preferably 3min-60min.

[0043] After obtaining the PVDF / MWCNT piezoelectric fibers attached to the middle roller, two PVB films are simultaneously passed through the upper and lower rollers of a three-roll calender for hot pressing. During the hot pressing process, the PVB film melts and comes into full contact with the piezoelectric fibers. After returning to room temperature, the film is removed, resulting in a modified PVB film. This modified PVB film contains piezoelectric fibers, which greatly improves the low-frequency sound insulation performance of the PVB film. In addition, by precisely controlling the conditions, good light transmittance can be maintained after hot pressing.

[0044] In this invention, the hot pressing temperature is preferably 50℃~150℃, more preferably 100℃~140℃; the roller linear speed is 2m / min~10m / min; and the roller spacing is 0.1mm~1.5mm.

[0045] The preparation method provided by this invention involves obtaining fibers through electrospinning, and then hot-pressing the fibers into a PVB film to obtain a piezoelectric fiber-reinforced PVB film. A flowchart of the overall preparation method can be found here. Figure 2 As shown; where ① is a PVB film, ② is a piezoelectric polymer fiber, ③ is a three-roll calender, and ④ is a PVB low-frequency sound insulation film. This preparation method yields a PVB low-frequency sound insulation film, which exhibits significantly improved low-frequency sound insulation performance, making it particularly suitable for use in laminated glass.

[0046] This invention also provides a PVB low-frequency sound insulation film for laminated glass, prepared using the method described above. This invention incorporates piezoelectric fibers within the PVB film, simplifying the process while providing the product with excellent overall low-frequency sound insulation performance.

[0047] This invention provides a PVB low-frequency sound insulation film for laminated glass and its preparation method. The preparation method includes the following steps: a) dispersing multi-walled carbon nanotubes in an organic solvent to obtain a suspension; b) dissolving a piezoelectric polymer in the suspension obtained in step a) to obtain an electrospinning solution; c) using the middle roller of a three-roll calender as a spinning receiver, electrospinning the electrospinning solution obtained in step b) while two PVB films enter through the upper and lower rollers of the three-roll calender. Through the heating and pressing action of the three-roll calender, the electrostatic fiber film is sandwiched between the PVB films to obtain a PVB low-frequency sound insulation film for laminated glass. This preparation method obtains piezoelectric fibers through electrospinning, and then composites the fibers with a PVB film through hot pressing to obtain a piezoelectric fiber-reinforced PVB film. The low-frequency sound insulation performance of this material is significantly improved, making it particularly suitable for PVB low-frequency sound insulation films for laminated glass.

[0048] Furthermore, the preparation method provided by this invention can control the light transmittance of laminated glass by controlling the reaction conditions, thus maintaining good light transmittance of the product and having broad application prospects.

[0049] To further illustrate the present invention, detailed descriptions are provided below through examples. All pharmaceuticals and solvents used in the following examples of the present invention are commercially available. Example

[0050] (1) Multi-walled carbon nanotubes (MWCNTs) are ultrasonically dispersed in a mixed organic solvent of DMF:ACE=3:2 (volume ratio) to form a suspension. Then, polyvinylidene fluoride (PVDF) is dissolved in the above suspension to prepare a PVDF / MWCNT solution with a PVDF mass fraction of 12% and a MWCNT mass fraction of 0.01%, which is an electrospinning solution.

[0051] (2) Using an electrospinning test apparatus, under an electric field strength of 15kV, the middle roller of a three-roll calender was used as the spinning receiver for electrospinning. See [reference needed]. Figure 1 As shown, the syringe of the electrospinning test device is a 5mL medical syringe, the inner diameter of the spinneret is 0.34mm, the needle tip is flat, the distance between the tip of the spinneret and the roller is 20cm, the electrospinning solution is fed at a rate of 1mL / h, the electrospinning time is 30min, and PVDF / MWCNT piezoelectric fibers are obtained attached to the intermediate roller.

[0052] (3) At the same time, two PVB films are fed into the upper and lower rollers of the three-roll calender. The electrostatic fiber film is sandwiched in the middle of the PVB film by the heating and pressing action of the three-roll calender. The hot pressing temperature is 110℃, the roller linear speed is 5m / min, and the roller spacing is 0.8mm. PVB low-frequency sound insulation film for laminated glass is obtained. The transmittance of the laminated glass obtained in this way is 84%. Example

[0053] (1) Multi-walled carbon nanotubes (MWCNTs) are ultrasonically dispersed in a mixed organic solvent of DMF:ACE=3:2 (volume ratio) to form a suspension. Then, polyvinylidene fluoride (PVDF) is dissolved in the above suspension to prepare a PVDF / MWCNT solution with a PVDF mass fraction of 15% and a MWCNT mass fraction of 0.01%, which is an electrospinning solution.

[0054] (2) Using an electrospinning test apparatus, under an electric field strength of 15kV, the middle roller of a three-roll calender was used as the spinning receiver for electrospinning. See [reference needed]. Figure 1 As shown, the syringe of the electrospinning test device is a 5mL medical syringe, the inner diameter of the spinneret is 0.34mm, the needle tip is flat, the distance between the tip of the spinneret and the roller is 20cm, the electrospinning solution is fed at a rate of 1mL / h, the electrospinning time is 30min, and PVDF / MWCNT piezoelectric fibers are obtained attached to the intermediate roller.

[0055] (3) Simultaneously, two PVB films are fed into the upper and lower rollers of a three-roll calender. Through the heating and pressing action of the three-roll calender, the electrostatic fiber film is sandwiched between the PVB films. The hot pressing temperature is 110℃, the roller linear speed is 5m / min, and the roller spacing is 0.8mm, thus obtaining a PVB low-frequency sound insulation film for laminated glass. The transmittance of the laminated glass produced in this way is 82%. Example

[0056] (1) Multi-walled carbon nanotubes (MWCNTs) are ultrasonically dispersed in a mixed organic solvent of DMF:ACE=3:2 (volume ratio) to form a suspension. Then, polyvinylidene fluoride (PVDF) is dissolved in the above suspension to prepare a PVDF / MWCNT solution with a PVDF mass fraction of 18% and a MWCNT mass fraction of 0.01%, which is an electrospinning solution.

[0057] (2) Using an electrospinning test apparatus, under an electric field strength of 15kV, the middle roller of a three-roll calender was used as the spinning receiver for electrospinning. See [reference needed]. Figure 1 As shown, the syringe of the electrospinning test device is a 5mL medical syringe, the inner diameter of the spinneret is 0.34mm, the needle tip is flat, the distance between the tip of the spinneret and the roller is 20cm, the electrospinning solution is fed at a rate of 1mL / h, the electrospinning time is 30min, and PVDF / MWCNT piezoelectric fibers are obtained attached to the intermediate roller.

[0058] (3) At the same time, two PVB films are fed into the upper and lower rollers of the three-roll calender. The electrostatic fiber film is sandwiched in the middle of the PVB film by the heating and pressing action of the three-roll calender. The hot pressing temperature is 110℃, the roller linear speed is 5m / min, and the roller spacing is 0.8mm. PVB low-frequency sound insulation film for laminated glass is obtained. The transmittance of the laminated glass obtained in this way is 81%. Example

[0059] (1) Multi-walled carbon nanotubes (MWCNTs) are ultrasonically dispersed in a mixed organic solvent of DMF:ACE=3:2 (volume ratio) to form a suspension. Then, polyvinylidene fluoride (PVDF) is dissolved in the above suspension to prepare a PVDF / MWCNT solution with a PVDF mass fraction of 18% and a MWCNT mass fraction of 0.1%, which is an electrospinning solution.

[0060] (2) Using an electrospinning test apparatus, under an electric field strength of 15kV, the middle roller of a three-roll calender was used as the spinning receiver for electrospinning. See [reference needed]. Figure 1 As shown, the syringe in the electrospinning experimental apparatus is a 5mL medical syringe, the inner diameter of the spinneret is 0.34mm, the needle tip is flat, the distance between the tip of the spinneret and the roller is 20cm, the electrospinning solution is fed at a rate of 1mL / h, and the electrospinning time is 30min, resulting in PVDF / MWCNT piezoelectric fibers attached to the intermediate roller. The morphology of the piezoelectric fibers is shown in the attached figure. Figure 3 The fiber diameter is around 500 nanometers. See the attached image for the piezoelectric properties of the piezoelectric fiber membrane. Figure 4 The fiber membrane can continuously output a voltage of approximately 1.7V.

[0061] (3) Simultaneously, two PVB films are fed into the upper and lower rollers of a three-roll calender. Through the heating and pressing action of the three-roll calender, the electrostatic fiber film is sandwiched between the PVB films. The hot pressing temperature is 110℃, the roller linear speed is 5m / min, and the roller spacing is 0.8mm, thus obtaining a PVB low-frequency sound insulation film for laminated glass. The sound insulation characteristic curve of the sample is shown in the appendix. Figure 5 The resulting laminated glass has a light transmittance of 80% (see attached figure 6) and excellent impact resistance (see attached figure 7). Figure 7 . Example

[0062] (1) Multi-walled carbon nanotubes (MWCNTs) are ultrasonically dispersed in DMF to form a suspension, and then polyacrylonitrile (PAN) is dissolved in the above suspension to prepare a PAN / MWCNT solution with a PAN mass fraction of 13% and a MWCNT mass fraction of 0.01%, which is an electrospinning solution.

[0063] (2) Using an electrospinning test apparatus, under an electric field strength of 15kV, the middle roller of a three-roll calender was used as the spinning receiver for electrospinning. See [reference needed]. Figure 1 As shown, the syringe of the electrospinning test device is a 5mL medical syringe, the inner diameter of the spinneret is 0.34mm, the needle tip is flat, the distance between the tip of the spinneret and the roller is 20cm, the electrospinning solution is fed at a rate of 1mL / h, the electrospinning time is 30min, and PVDF / MWCNT piezoelectric fibers are obtained attached to the intermediate roller.

[0064] (3) Simultaneously, two PVB films are fed into the upper and lower rollers of a three-roll calender. Through the heating and pressing action of the three-roll calender, the electrostatic fiber film is sandwiched between the PVB films. The hot pressing temperature is 110℃, the roller linear speed is 5m / min, and the roller spacing is 0.8mm, thus obtaining a PVB low-frequency sound insulation film for laminated glass. The transmittance of the laminated glass produced in this way is 78%.

[0065] Comparative Example 6

[0066] Two PVB films are placed together in a three-roll calender for hot pressing at a temperature of 110°C, a roller linear speed of 5 m / min, and a roller gap of 0.8 mm to obtain a PVB film for laminated glass. The laminated glass produced in this way has a transmittance of 85%.

[0067] According to the national standard GB / Z 27764-2011, the sound insulation of the PVB low-frequency sound insulation film for laminated glass prepared by the preparation methods provided in Examples 1-5 and the PVB film prepared by the preparation method provided in Comparative Example 1 were tested. The results of low-frequency sound insulation are shown in Table 1.

[0068] Table 1. Transmission loss of PVB low-frequency sound insulation film and PVB film at different frequencies within the quality control area.

[0069] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown in the text, but is accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for preparing a PVB low-frequency sound-insulating film for laminated glass, comprising the following steps: a) Dispersing multi-walled carbon nanotubes in an organic solvent to obtain a suspension, characterized in that the mass fraction of multi-walled carbon nanotubes in the suspension is 0.01%, and the organic solvent is a mixture of two organic solvents; b) Dissolve the piezoelectric polymer in the suspension obtained in step a) to obtain an electrospinning solution, characterized in that the mass fraction of the polymer in the electrospinning solution in step b) is 12%~18%; c) Using the middle roller of a three-roll calender as a spinning receiver, electrospin the electrospinning solution obtained in step b) simultaneously, two PVB films enter through the upper and lower rollers of the three-roll calender, and through the heating and pressing action of the three-roll calender, the electrostatic fiber film is sandwiched in the middle of the PVB film to obtain a PVB low-frequency sound insulation film for laminated glass, characterized in that the hot pressing temperature is 110℃~140℃, the roller linear speed is 5~10m / min, and the roller spacing is 0.8~1.5mm.

2. The method for preparing a PVB low-frequency sound-insulating film for laminated glass according to claim 1, characterized in that, The organic solvent mentioned in step a) includes two of the following: dimethylformamide, dimethylacetamide, dimethyl sulfoxide, acetone, dichloromethane, and chloroform.

3. The method for preparing a PVB low-frequency sound-insulating film for laminated glass according to claim 1, characterized in that, The piezoelectric polymer mentioned in step b) includes one or more of polyvinylidene fluoride, polymethyl methacrylate, and polyacrylonitrile.

4. The method for preparing a PVB low-frequency sound-insulating film for laminated glass according to claim 1, characterized in that, The electrospinning process described in step c) uses a spinneret with an inner diameter of 0.34 mm to 1.0 mm, a distance of 20 cm to 30 cm between the tip and the collecting device, and a spinning time of 30 min to 60 min.

5. The method for preparing a PVB low-frequency sound-insulating film for laminated glass according to claim 1, characterized in that, The electric field strength of the electrospinning described in step c) is 15kV~30kV, and the propulsion rate of the micro-injection pump is 1mL / h~1.50mL / h.

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