Preparation method of high-performance ecological membrane based on RPVB

Abstract

The invention discloses a preparation method of a high-performance ecological membrane based on RPVB (Reactive Polyvinyl Butyral), which is characterized by comprising the following steps: raw material treatment: cleaning, crushing and separating recycled automobile windshield laminated material RPVB; glue blending, wherein the RPVB particles and environment-friendly glue are mixed according to the mass ratio of 1: (0.9-1.1); coating and transferring; drying and curing; carrying out post-treatment; the waste automobile windshield laminated material RPVB is used as a main raw material, high-value utilization of waste resources is achieved, environmental pollution of solid waste is reduced, the problem of environmental pollution in the production and use process is avoided, and by optimizing the formula and the process, the production cost is reduced, and the production efficiency is improved. The ecological membrane shows excellent performance in the aspects of strength, wear resistance, flexibility, air permeability and the like, the used environment-friendly glue is waterborne polyurethane emulsion meeting the REACH standard of European Union, a plasticizer is not contained, a full-water-based technology is matched, it is ensured that no volatile organic compound (VOC) is discharged in the production process, and the ecological membrane is more friendly to the human body and the environment.

Description

Technical Field

[0001] The invention relates to the technical field of ecological membranes, and in particular to a method for preparing a high-performance ecological membrane based on RPVB. Background Art

[0002] Common high-performance membrane materials on the market today, such as polyurethane (PU), thermoplastic polyurethane (TPU), thermoplastic elastomer (TPE) and polytetrafluoroethylene (PTFE), show good performance in terms of wear resistance, adhesion and cold resistance. However, these materials may produce harmful byproducts during production and use, causing certain harm to the environment. At the same time, these traditional membrane materials also have certain limitations in terms of flexibility and environmental protection, and it is difficult to fully meet the high requirements of modern textiles for sustainability and comfort.

[0003] RPVB is a material made from renewable resources, which has good environmental protection and recycling potential. However, the direct use of RPVB has deficiencies in adhesion and flexibility, and it is difficult to meet the requirements of high-performance membrane materials. Therefore, it is necessary to optimize its preparation process and composition in order to improve its physical and chemical properties, so as to achieve wider application in high-performance textile fabric coating. To solve the above problems, we propose a preparation method of high-performance ecological membrane based on RPVB. Summary of the invention

[0004] In view of the deficiencies in the prior art, the present invention provides a method for preparing a high-performance ecological membrane based on RPVB to solve the problems raised in the background technology.

[0005] The above technical objectives of the present invention are achieved through the following technical solutions: A method for preparing a high-performance ecological membrane based on RPVB comprises the following steps: Raw material processing: The recycled automobile windshield laminated material RPVB is cleaned, crushed and separated. During cleaning, a neutral detergent with a mass concentration of 2-5% is added to deionized water at 70°C, and ultrasonic vibration treatment with a frequency of 40 kHz is used for 5-10 minutes, and mechanical stirring is combined to remove surface impurities. After that, the cleaned RPVB material is dried to a moisture content of less than 0.5%, and crushed using a ball mill or airflow mill to obtain pure RPVB particles with a particle size of 10-50 microns; Glue preparation: The treated RPVB particles are mixed with environmentally friendly glue at a mass ratio of 1:0.9-1.1. The environmentally friendly glue is composed of water-based polyurethane emulsion, modification additives and nano-functional fillers, wherein the nano-functional fillers include 0.1-0.3% of nano zinc oxide and 0.2-0.5% of nano silicon dioxide particles. The viscosity of the glue is controlled at 800-1200 mPa·s. The mixture is stirred at a stirring speed of 2500-3500 rpm for 15-20 minutes. During the process, the temperature of the mixture is controlled at 30-40°C by intermittent heating to improve uniformity and adhesion performance; Coating transfer: The mixed glue and particles are evenly coated on the surface of the substrate through a dynamic temperature-controlled roller coating device. The coating thickness is controlled at 15-25 microns. The coating process adopts a dual-temperature zone heating structure. The temperature of the first temperature zone is 25-30°C, and the temperature of the second temperature zone is 50-60°C. The coating thickness fluctuation is reduced by gradually increasing the temperature. At the same time, an infrared thickness gauge is equipped to monitor the coating thickness deviation in real time and control it within ±2 microns; Drying and curing: The coated substrate is placed at 60-70°C for pre-drying for 3-5 minutes to allow the coating to be initially formed, and then the temperature is gradually raised to 80-100°C. Under this condition, curing treatment is performed for 5-7 minutes to enhance the structural stability and adhesion performance of the coating and form a dense coating; Post-treatment: The cured film layer is subjected to plasma surface treatment using low-temperature radio frequency plasma equipment with a processing power of 50-100 W and a processing time of 1-3 minutes. This treatment method further improves the surface density, water resistance and antifouling properties of the coating to obtain a high-performance ecological film.

[0006] Preferably, the RPVB particles are surface modified after crushing, and the particles are coated with a silane coupling agent, wherein the silane coupling agent is preferably KH-550 or KH-560, the treatment temperature is 60-70°C, and the treatment time is 2-5 hours, so as to enhance the interfacial bonding force between the particles and the environmentally friendly glue.

[0007] Preferably, when the nano-functional filler is dispersed in the glue, a high shear emulsifier is used for pre-dispersion treatment, wherein the speed of the high shear emulsifier is set to 8000-12000 rpm and the dispersion time is 10-15 minutes to improve the distribution uniformity and stability of the nanoparticles in the glue.

[0008] Preferably, the coating thickness is adjusted in real time during the coating process, and a closed-loop control system is used to automatically adjust the pressure and speed of the roller coater according to the monitoring data of the infrared thickness gauge to control the coating thickness deviation within ±1.5 microns.

[0009] Preferably, the temperature gradient of the curing process is set as follows: pre-drying at 60°C for 4 minutes, then heating to 90°C and maintaining for 5 minutes for curing to ensure the adhesion and anti-delamination properties of the film layer.

[0010] Preferably, during the plasma surface treatment process, the gas environment is a mixed gas of argon and oxygen, wherein the volume ratio of argon to oxygen is 3:1, so as to form a micro-nanoscale surface modification layer, thereby enhancing the anti-fouling and antibacterial properties of the coating.

[0011] Preferably, the main application fields of the obtained ecological film include clothing fabrics, home textile fabrics and luggage fabrics, which are used to improve the anti-down property, Q-elastic feel, breathability, wear resistance and antibacterial properties.

[0012] In summary, the present invention mainly has the following beneficial effects: 1. The present invention uses waste automobile windshield laminated material RPVB as the main raw material, and realizes the high-value utilization of waste resources through steps such as cleaning, crushing, separation and surface modification, which not only reduces the environmental pollution of solid waste, but also conforms to the concept of green and sustainable development, and avoids environmental pollution problems during production and use. This ecological film not only reduces resource consumption and waste emissions, but also significantly reduces carbon emissions.

[0013] 2. By optimizing the formula and process, the ecological film of the present invention exhibits excellent performance in terms of strength, wear resistance, flexibility and air permeability, ensuring performance stability and durability in long-term use. At the same time, the film can still remain flexible under low temperature conditions and will not crack. It is suitable for outdoor applications in cold climates and meets the use requirements under extreme climatic conditions.

[0014] 3. The present invention adopts a variety of innovative process means to effectively improve the uniformity and stability of the membrane material. Through the high-shear emulsification dispersion process, the uniformity of particle dispersion is improved, and the adhesion and wear resistance of the film layer are significantly improved. The environmentally friendly glue used is an aqueous polyurethane emulsion that meets the EU REACH standard and does not contain plasticizers. Combined with the all-water process, it ensures that there is no volatile organic compound (VOC) emission during the production process, which is more friendly to the human body and the environment. DETAILED DESCRIPTION

[0015] The following examples are used to illustrate the present invention, but they cannot be used to limit the scope of protection of the present invention. The conditions in the examples can be further adjusted according to specific conditions. Simple improvements to the method of the present invention under the premise of the concept of the present invention belong to the scope of protection claimed in the present invention.

[0016] Embodiment 1, a method for preparing a high-performance ecological membrane based on RPVB, comprising the following steps:

[0017] The recycled automobile windshield laminated material RPVB was cleaned and crushed, and then cleaned with 70°C deionized water and 3% neutral detergent, combined with 40 kHz ultrasonic vibration for 8 minutes to remove impurities; The cleaned RPVB is dried to a moisture content of less than 0.5%, and crushed to a particle size of 10-30 microns using a jet mill; The surface of RPVB particles was modified using 2% silane coupling agent (KH-550) at 60°C for 4 hours to enhance the bonding strength between the particles and the glue.

[0018] To prepare environmentally friendly glue, water-based polyurethane emulsion (solid content 50%, viscosity 1000 mPa·s) was selected, and 0.2% nano zinc oxide and 0.5% nano silicon dioxide particles were added as fillers; The nanofillers were pre-dispersed using a high shear emulsifier at a speed of 10,000 rpm and a dispersion time of 15 min; The RPVB particles and the environmentally friendly glue were mixed in a mass ratio of 1:1, with a stirring speed of 3000 rpm and a stirring time of 20 minutes. The temperature of the mixture was controlled at 35°C.

[0019] The mixture was evenly coated on the surface of the polyester substrate using a dynamic temperature-controlled roller coating device, and the coating thickness was controlled at 20 microns; The coating temperature zone 1 was set to 25°C, the temperature zone 2 was set to 55°C, and the infrared thickness gauge monitored the coating thickness deviation (±1.5 μm) in real time.

[0020] The coated substrate was dried at 70°C for 3 minutes; Then the temperature was raised to 90°C for curing for 5 minutes to obtain a preliminary ecological film with a uniform structure.

[0021] A low-temperature radio frequency plasma device was used with a gas environment of argon and oxygen (3:1), a processing power of 80 W, and a processing time of 2 minutes to modify the membrane surface and improve its wear resistance and antibacterial properties.

[0022] Performance test results: tensile strength: 22 MPa, water vapor transmission rate: 2800 g / m²·24h, abrasion resistance: no damage after 50,000 frictions, low temperature flexibility: no cracks after 20 bends at -30℃.

[0023] Embodiment 2, a method for preparing a high-performance ecological membrane based on RPVB, comprising the following steps:

[0024] The recovered RPVB laminated materials were collected and cleaned by adding 5% neutral detergent to 70°C deionized water and then cleaning with ultrasonic vibration (40 kHz) for 10 minutes while mechanically stirring. After the cleaned RPVB particles are dried, they are crushed to 30-50 microns using a ball mill to ensure uniform particle size distribution; Use 3% silane coupling agent (KH-560) and treat at 70°C for 3 hours to improve the particle interface affinity.

[0025] The glue is made of environmentally friendly water-based polyurethane emulsion, and the viscosity is controlled at 1200 mPa·s; Add 0.1% nano zinc oxide and 0.3% nano silicon dioxide particles as antibacterial and wear-resistant enhancers; The RPVB particles were mixed with glue at a mass ratio of 1:0.9, with a stirring speed of 3500 rpm for 18 minutes, and the temperature of the mixture was controlled at 30 °C.

[0026] The mixture was applied on a pure cotton substrate using an automatic roller coater with a coating thickness of 25 μm; The coating temperature zone 1 was set to 30°C, and the temperature zone 2 was set to 60°C. The infrared thickness gauge was used for dynamic monitoring and the deviation was adjusted to ±2 microns.

[0027] Dry at 60°C for 5 minutes, then heat to 100°C for 7 minutes to ensure coating density and adhesion.

[0028] The membrane surface was treated by low-temperature radio frequency plasma equipment (power 60 W, time 3 minutes) in an argon environment to improve its antifouling property and surface smoothness.

[0029] Performance test results: tensile strength: 21 MPa, wear resistance: no obvious wear after 60,000 frictions, surface hydrophobic angle: 110° (significant anti-fouling), low-temperature flexibility: no cracks after 20 bends at -30°C.

[0030] Specifically, the performance differences of the finished films prepared in Example 1 and Example 2 were measured, as shown in the following table: parameter Example 1 Example 2 RPVB particle size 10-30 μm 30-50 μm Environmentally friendly glue viscosity 1000 mPa·s 1200 mPa·s Coating thickness 20 μm 25 μm Coating uniformity deviation ±1.5 μm ±2 microns Tensile Strength 22 MPa 21 MPa Wear resistance 50,000 frictions without damage 60,000 frictions without noticeable wear Low temperature flexibility -30℃, 20 bendings without cracks -30℃, 20 bendings without cracks Water vapor transmission rate 5200 g / m²·24h 5000 g / m²·24h Moisture permeability resistance 10-15 m²Pa / W 10-15 m²Pa / W Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing a high-performance ecological membrane based on RPVB, characterized in that: The following steps are involved: Raw material processing: The recycled automobile windshield laminated material RPVB is cleaned, crushed and separated. During cleaning, a neutral detergent with a mass concentration of 2-5% is added to deionized water at 70°C, and ultrasonic vibration treatment with a frequency of 40 kHz is used for 5-10 minutes, and mechanical stirring is combined to remove surface impurities. After that, the cleaned RPVB material is dried to a moisture content of less than 0.5%, and crushed using a ball mill or airflow mill to obtain pure RPVB particles with a particle size of 10-50 microns; Glue preparation: The treated RPVB particles are mixed with environmentally friendly glue at a mass ratio of 1:0.9-1.

1. The environmentally friendly glue is composed of water-based polyurethane emulsion, modification additives and nano-functional fillers, wherein the nano-functional fillers include 0.1-0.3% of nano zinc oxide and 0.2-0.5% of nano silicon dioxide particles. The viscosity of the glue is controlled at 800-1200 mPa·s. The mixture is stirred at a stirring speed of 2500-3500 rpm for 15-20 minutes. During the process, the temperature of the mixture is controlled at 30-40°C by intermittent heating to improve uniformity and adhesion performance; Coating transfer: The mixed glue and particles are evenly coated on the surface of the substrate through a dynamic temperature-controlled roller coating device. The coating thickness is controlled at 15-25 microns. The coating process adopts a dual-temperature zone heating structure. The temperature of the first temperature zone is 25-30°C, and the temperature of the second temperature zone is 50-60°C. The coating thickness fluctuation is reduced by gradually increasing the temperature. At the same time, an infrared thickness gauge is equipped to monitor the coating thickness deviation in real time and control it within ±2 microns; Drying and curing: The coated substrate is placed at 60-70°C for pre-drying for 3-5 minutes to allow the coating to be initially formed, and then the temperature is gradually raised to 80-100°C. Under this condition, curing treatment is performed for 5-7 minutes to enhance the structural stability and adhesion performance of the coating and form a dense coating; Post-treatment: The cured film layer is subjected to plasma surface treatment using low-temperature radio frequency plasma equipment with a processing power of 50-100 W and a processing time of 1-3 minutes to obtain a high-performance ecological film.

2. The method for preparing a high-performance ecological membrane based on RPVB according to claim 1, characterized in that: The RPVB particles are surface modified after being crushed, and the particles are coated with a silane coupling agent, wherein the silane coupling agent is preferably KH-550 or KH-560, the treatment temperature is 60-70°C, and the treatment time is 2-5 hours, so as to enhance the interface bonding force between the particles and the environmentally friendly glue.

3. The method for preparing a high-performance ecological membrane based on RPVB according to claim 1, characterized in that: When the nano-functional filler is dispersed in the glue, a high shear emulsifier is used for pre-dispersion treatment, wherein the rotation speed of the high shear emulsifier is set to 8000-12000 rpm and the dispersion time is 10-15 minutes to improve the distribution uniformity and stability of the nano-particles in the glue.

4. The method for preparing a high-performance ecological film based on RPVB according to claim 1, characterized in that: The coating thickness is adjusted in real time during the coating process, and a closed-loop control system is used to automatically adjust the pressure and speed of the roller coater according to the monitoring data of the infrared thickness gauge, so that the coating thickness deviation is controlled within ±1.5 microns.

5. The method for preparing a high-performance ecological film based on RPVB according to claim 1, characterized in that: The temperature gradient of the curing process is set as follows: pre-drying at 60° C. for 4 minutes, then heating to 90° C. and maintaining for 5 minutes for curing to ensure the adhesion and anti-delamination properties of the film layer.

6. The method for preparing a high-performance ecological film based on RPVB according to claim 1, characterized in that: During the plasma surface treatment process, the gas environment is a mixed gas of argon and oxygen, wherein the volume ratio of argon to oxygen is 3:1, so as to form a micro-nanoscale surface modification layer, thereby enhancing the anti-fouling and antibacterial properties of the coating.

7. The method for preparing a high-performance ecological membrane based on RPVB according to claim 1, characterized in that: The main application areas of the obtained ecological film include clothing fabrics, home textile fabrics and luggage fabrics, which are used to improve the anti-down property, Q-elastic feel, breathability, wear resistance and antibacterial properties.