Double-system compound high-damping wide-temperature-range PVB (polyvinyl butyral) intermediate film, preparation method thereof and laminated glass

Abstract

The invention relates to the technical field of laminated glass intermediate films, in particular to a double-system compound high-damping wide-temperature-range PVB intermediate film, a preparation method thereof and laminated glass. The double-system compound high-damping wide-temperature-range PVB middle film is of a three-layer gradient structure and sequentially comprises a first surface layer, a middle sound insulation layer and a second surface layer from outside to inside. Each of the first surface layer and the second surface layer comprises first PVB (Polyvinyl Butyral) resin and a first compound plasticizer, and the first compound plasticizer comprises dibutoxyethyl adipate and triethylene glycol di-2-ethylhexanoate; the middle sound insulation layer comprises second PVB resin and a second compound plasticizer, and the second compound plasticizer comprises bis (butoxyethoxy ethyl) adipate and triethylene glycol di-2-ethyl hexanoate. According to the invention, a double-compound plasticizing system is constructed and is accurately matched with a three-layer gradient structure, so that the synergistic improvement of various properties in a wide temperature range is finally realized.

Description

Technical Field

[0001] This invention relates to the field of interlayer technology for laminated glass, and in particular to a dual-system composite high-damping wide-temperature-range PVB interlayer, its preparation method, and laminated glass. Background Technology

[0002] Laminated glass, as an important safety material, is widely used in automobiles, construction, and other fields. Its core performance lies in the polyvinyl butyral (PVB) interlayer. The PVB interlayer, through its adhesion and flexibility, allows the laminated glass to maintain its integrity upon impact, preventing shards from flying, while also providing sound and heat insulation. However, in extreme temperature environments such as cold regions, high altitudes, and tropical zones, the performance of traditional PVB interlayers faces severe challenges.

[0003] Currently, most existing PVB interlayer membranes use single ester plasticizers or non-targeted compound plasticizer systems, which have the following obvious defects: (1) Poor wide temperature range adaptability: In low temperature environments (such as -40℃), the interlayer membrane is prone to brittle cracking, and its flexibility and adhesion decrease significantly; while in high temperature environments (such as 80℃), the plasticizer is prone to migration and volatilization, resulting in softening of the interlayer membrane, weakening of adhesion, and insufficient long-term durability. (2) Narrow damping performance temperature range: The sound insulation performance of traditional interlayer membranes is unstable in a wide temperature range (-40℃~80℃), and the sound insulation fluctuation often exceeds 5dB, making it impossible to maintain an effective sound insulation effect at extreme temperatures. (3) Coarse design of plasticizer system: In existing technologies, the plasticizer system mostly uses single components or simple compounding, without refined design for the functional differences of different structural layers of the interlayer membrane (such as the surface layer and the intermediate layer). In particular, the specific interaction between amine plasticizers and PVB resin is not fully utilized, resulting in limited plasticizing effect and difficulty in balancing low-temperature flexibility and high-temperature stability. (4) Insufficient process adaptability: The traditional preparation process has not been optimized for the physicochemical properties of different compound plasticizer systems, resulting in uneven dispersion of plasticizer in resin, which further affects the performance consistency and long-term reliability of the intermediate film over a wide temperature range.

[0004] Therefore, there is an urgent need to develop a PVB interlayer that can combine high damping, strong adhesion, low migration, and long-term stability over a wide temperature range (-40℃ to 80℃) to meet the application requirements in extreme environments. Summary of the Invention

[0005] The purpose of this invention is to address the problems existing in the prior art by providing a dual-system composite high-damping wide-temperature-range PVB interlayer film, its preparation method, and laminated glass. By constructing a dual-composite plasticizing system of "DBEA / 3GO (surface layer) + DBEEA / 3GO (interlayer)" and precisely matching it with a three-layer gradient structure, a synergistic improvement of multiple properties under a wide temperature range is achieved.

[0006] To achieve the above objectives, the present invention provides a dual-system composite high-damping wide-temperature-range PVB interlayer membrane, wherein the interlayer membrane has a three-layer gradient structure, consisting of a first surface layer, a middle sound-insulating layer, and a second surface layer from the outside to the inside. Both the first surface layer and the second surface layer contain a first PVB resin and a first compound plasticizer, wherein the first compound plasticizer includes dibutoxyethyl adipate (DBEA) and triethylene glycol di-2-ethylhexanoate (3GO). The intermediate sound insulation layer comprises a second PVB resin and a second compound plasticizer, the second compound plasticizer comprising di(butoxyethoxyethyl) adipic acid ester (DBEEA) and triethylene glycol di-2-ethylhexanoate (3GO).

[0007] The CAS number for dibutoxyethyl adipic acid is 141-18-4; the CAS number for di(butoxyethoxyethyl) adipic acid is 141-17-3; and the CAS number for triethylene glycol di-2-ethylhexanoate is 94-28-0.

[0008] In an optional embodiment, in the first compound plasticizer, the mass ratio of dibutoxyethyl adipate to triethylene glycol di-2-ethylhexanoate is 1:(4~10); and the mass ratio of the first PVB resin to the first compound plasticizer is 100:(28~35).

[0009] In this invention, in the first compound plasticizer, the amine group in the DBEA molecule can form a strong hydrogen bond with the hydroxyl group of the PVB resin, effectively improving the flexibility of the interlayer film in low-temperature environment and the adhesion stability with glass; at the same time, 3GO, as a basic plasticizer with excellent compatibility, ensures the full integration of the entire plasticizing system with the PVB resin and provides the necessary basic flexibility.

[0010] In an optional embodiment, in the second compound plasticizer, the mass ratio of di(butoxyethoxyethyl) adipic acid ester and triethylene glycol di-2-ethylhexanoate is 1:(1.5~4); the mass ratio of the second PVB resin and the second compound plasticizer is 100:(65~80).

[0011] In this invention, the ethoxy chain segment in the DBEEA molecule of the second compound plasticizer helps to broaden the effective damping temperature range of the polymer system, thereby significantly enhancing the sound insulation performance stability of the interlayer in a wide temperature range (especially the high temperature range); at the same time, the addition of 3GO further optimizes the compatibility between the plasticizer and PVB resin and improves the melt flowability of the mixture during processing, ensuring the uniformity of the intermediate sound insulation layer components and the molding quality.

[0012] In an optional embodiment, the first PVB resin has a weight-average molecular weight of 190,000 to 230,000, a hydroxyl content of 12 to 28 mol%, a degree of acetylation of 0.8 to 10 mol%, and a degree of acetalization of 66 to 76 mol.

[0013] In an optional embodiment, the second PVB resin has a weight-average molecular weight of 70,000 to 90,000, a hydroxyl content of 15 to 27 mol%, a degree of acetylation of 6 to 11 mol%, and a degree of acetalization of 69 to 77 mol%.

[0014] In an optional embodiment, the first surface layer and the second surface layer further comprise an ultraviolet shielding agent, an antioxidant, and a metal salt, respectively; the ultraviolet shielding agent is selected from 2-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole; the antioxidant includes 2,6-di-tert-butyl-p-cresol and tris(2,4-di-tert-butylphenyl) phosphite, with a mass ratio of 2,6-di-tert-butyl-p-cresol to tris(2,4-di-tert-butylphenyl) phosphite of (1.5~2.5):1; the metal salt includes magnesium acetate and potassium 2-ethylhexanoate, with a mass ratio of magnesium acetate to potassium 2-ethylhexanoate of 1:(1.5~2.5).

[0015] In an optional embodiment, the mass fractions of the ultraviolet shielding agent in the first surface layer and the second surface layer are 0.4-0.7%, the mass fractions of the antioxidant are 0.2-0.4%, and the content of the metal salt is 30-100 ppm.

[0016] In an optional embodiment, the intermediate sound-insulating layer further comprises a hindered amine light stabilizer selected from bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate.

[0017] In an optional embodiment, the mass fraction of the hindered amine light stabilizer in the intermediate sound-insulating layer is 0.2-0.4%.

[0018] In one optional embodiment, the thickness ratio of the first surface layer, the intermediate sound insulation layer, and the second surface layer is (30~40):(20~40):(30~40); the total thickness of the intermediate film is 0.5~1.2 mm.

[0019] The present invention also provides a method for preparing the aforementioned dual-system composite high-damping wide-temperature-range PVB interlayer, comprising the following steps: S1. Prepare the first surface layer premix, the middle sound insulation layer premix, and the second surface layer premix respectively; S2. The first surface layer premix, the middle sound insulation layer premix, and the second surface layer premix are melt-extruded and co-extruded to form a melt film. S3. The molten film is sequentially subjected to casting, cooling, and curing treatments to obtain the dual-system composite high-damping wide-temperature-range PVB interlayer film.

[0020] In an optional implementation, S1 specifically includes the following steps: (1) Raw material pretreatment The first PVB resin and the second PVB resin were dried at a temperature of 85~95℃ and a vacuum degree of -0.085~-0.095MPa for 5~7 hours to fully remove the moisture contained in the resin and avoid the moisture affecting the uniform dispersion of the plasticizer and the final film quality.

[0021] DBEA and 3GO were mixed at a mass ratio of 1:(4~10) at a temperature of 55~65℃ and a rotation speed of 400~600 r / min for 20~30 min until homogeneous, thus obtaining the first compound plasticizer. DBEA and 3GO were then mixed at a mass ratio of 1:(1.5~4) at a temperature of 60~70℃ and a rotation speed of 500~700 r / min for 25~35 min until homogeneous, thus obtaining the second compound plasticizer.

[0022] The hindered amine light stabilizer was added to 3GO (the mass ratio of hindered amine light stabilizer to 3GO was 1: (5~10)) and dispersed at high speed for 20~30 min at a temperature of 23~25℃ and a rotation speed of 1500~2500 r / min to obtain a stabilizer dispersion.

[0023] (2) Preparation of premixes for each layer Preparation of the first / second surface layer premix: The first PVB resin, the first compound plasticizer and other additives (ultraviolet shielding agent, antioxidant and metal salt) are mixed for 35 to 45 minutes at a temperature of 85 to 95°C and a rotation speed of 600 to 900 r / min to obtain the first surface layer premix and the second surface layer premix.

[0024] Preparation of the intermediate sound insulation layer premix: The second PVB resin and the second compound plasticizer are mixed at a temperature of 80~90℃ and a rotation speed of 700~1000r / min for 25~35min, and then the stabilizer dispersion is added and the mixture is continued to be mixed for 20~25min to obtain the intermediate sound insulation layer premix.

[0025] In an optional embodiment, in S2, the melt extrusion temperatures of the first surface layer premix and the second surface layer premix are 165~185℃, respectively; and the melt extrusion temperature of the intermediate sound insulation layer premix is ​​155~175℃.

[0026] In an optional embodiment, in S2, after melt extrusion, the material is filtered through a 200-300 mesh metal filter to remove impurities and unmelted particles, thereby improving the purity of the film material. Subsequently, the filtered molten material is conveyed to a three-layer co-extrusion die. At a die temperature of 175-190°C, the first surface layer, the intermediate sound insulation layer, and the second surface layer are sequentially composited and tightly bonded through precise distribution of the flow channels within the die, forming a gradient structure molten film with good interface fusion and stable structure.

[0027] In an optional embodiment, in step S3, the molten film is cast onto a four-segment cooling roller assembly for gradient cooling and shaping. The temperatures of each cooling roller segment are controlled sequentially as follows: first segment 85~95℃, second segment 60~70℃, third segment 40~50℃, and fourth segment 25~35℃; the film traction speed is controlled at 1.2~2.5 m / min. Through the combination of gradient cooling and uniform traction, the film material is slowly and uniformly cooled and solidified, effectively reducing internal stress and improving its dimensional stability over a wide temperature range.

[0028] In an optional embodiment, in S3, the cooled and shaped membrane material undergoes the following post-processing steps in sequence: (1) Thickness measurement and trimming: The membrane material is continuously measured using an online laser thickness gauge with a thickness measurement accuracy of ±0.003mm. Based on the thickness measurement results, the membrane material is trimmed on both sides using an edge trimming machine to control its width to 1.3~1.6m and the edge straightness error to ≤0.4mm / m, so as to ensure that the membrane material size is consistent. (2) Embossing treatment: The trimmed film material is fed into the embossing roller and embossed under the conditions of temperature of 45~55℃ and pressure of 0.4~0.6MPa to form a uniform embossed pattern with a pattern depth of 6~12μm to enhance the adhesion between the film material and the glass. (3) Traction and winding: The traction tension is controlled at 60~90N by the tension controller so that the embossed film is wound onto the paper core. The winding speed is synchronized with the traction speed and the speed error is ≤0.1m / min. During the winding process, the edge control system is used to ensure that the winding alignment error is ≤0.8mm.

[0029] In an optional embodiment, in step S3, the curing treatment is carried out at a temperature of 20-30°C, a relative humidity of 30-40%, and a time of 80-96 hours. This process allows for the full release of internal stress in the membrane material and promotes a stable interaction between the two compound plasticizing systems and the PVB resin, thereby obtaining a target intermediate membrane with balanced performance and stable structure.

[0030] The present invention also provides a laminated glass comprising two glass substrates disposed opposite to each other, and the aforementioned dual-system composite high-damping wide-temperature-range PVB interlayer sandwiched between the two glass substrates.

[0031] In an optional embodiment, the method for preparing the laminated glass includes the following steps: The first glass substrate, the intermediate film, and the second glass substrate are sequentially stacked and placed in a vacuum laminator. They are pre-pressed for 35 to 45 minutes at a temperature of 95 to 105°C and a vacuum degree of -0.092 to -0.098 MPa to fully expel interlayer air. The pre-pressed composite is then transferred to an autoclave and subjected to high-temperature and high-pressure pressing at 125 to 145°C and 1.3 to 1.6 MPa for 70 to 100 minutes to form a strong and dense bond between the intermediate film and the glass substrate, thereby obtaining the laminated glass.

[0032] The beneficial effects of this invention are as follows: (1) By constructing a dual-composite plasticizing system of "DBEA / 3GO (surface layer) + DBEEA / 3GO (intermediate layer)" and precisely matching it with a three-layer gradient structure, a synergistic improvement of multiple properties under a wide temperature range was achieved. The surface layer adopts the DBEA / 3GO composite system. By utilizing the strong hydrogen bonding between the amine group in the DBEA molecule and the hydroxyl group in the PVB resin, the flexibility of the intermediate film at low temperature (-40℃) and the interfacial bonding stability with the glass are effectively enhanced, solving the problem of low-temperature brittleness of traditional intermediate films. The intermediate sound insulation layer adopts the DBEEA / 3GO composite system. By utilizing the effect of the ethoxy chain segment in the DBEEA molecule on the broadening of the polymer damping temperature range, the sound insulation performance stability of the intermediate film in a wide temperature range (-40℃~80℃) is significantly improved. Both systems are well compatible with 3GO, and through the gradient structure design, their respective advantages are fully utilized in the corresponding functional layers, breaking through the limitation that the performance of a single or non-targeted composite system is difficult to achieve simultaneously.

[0033] (2) The PVB interlayer provided by this invention exhibits excellent overall performance. Specifically, the interlayers prepared in Examples 1-5 of this invention show no cracks when bent 180° at -40℃; after aging at 80℃ for 1000 hours, the plasticizer migration rate is only 1.5~1.9%; within a wide temperature range of -40℃ to 80℃, the sound insulation at 315Hz is ≥42dB, and the sound insulation fluctuation is ≤1.0dB; simultaneously, the visible light transmittance of the interlayer is ≥88%, the bonding strength with glass is ≥27N / cm, and it exhibits excellent weather resistance (gap ≤0.5mm after first light irradiation). The above data prove that this invention has achieved comprehensive and significant progress in low-temperature flexibility, high-temperature stability, wide-temperature-range high-damping sound insulation, strong adhesion, and durability.

[0034] (3) The preparation process is highly targeted and easy to implement, with good industrialization prospects. The method of this invention optimizes key process parameters such as premixing temperature, stirring speed, and melt extrusion temperature for the physicochemical properties of the two compound plasticizing systems, ensuring uniform dispersion of the plasticizer and stable composite structure of each layer. The entire process is based on the core process of the existing PVB film production line, requiring only adjustment of local parameters without major equipment modifications, making it highly feasible and cost-controllable. The resulting intermediate film is particularly suitable for automotive windshields, building curtain walls, and other scenarios in extreme temperature environments such as cold regions, high altitudes, and tropical regions, meeting the stringent requirements for wide-temperature performance stability and efficient sound insulation, and has broad application prospects. Detailed Implementation

[0035] The following embodiments are provided to better understand the present invention and are not limited to the preferred embodiments described. They do not constitute a limitation on the content and scope of protection of the present invention. Any product that is the same as or similar to the present invention, derived by any person under the guidance of the present invention or by combining the features of the present invention with other prior art, falls within the protection scope of the present invention.

[0036] For experiments not specifically described in the examples, the procedures or conditions should be followed according to the conventional experimental procedures described in the literature in this field. Reagents or instruments whose manufacturers are not specified are all commercially available conventional reagent products.

[0037] Example 1 This embodiment provides a dual-system composite high-damping wide-temperature-range PVB interlayer.

[0038] (1) Structural design: The intermediate membrane is a three-layer gradient structure with a total thickness of 0.6 mm. The thickness of the first surface layer and the second surface layer is 0.18 mm, and the thickness of the middle sound insulation layer is 0.24 mm.

[0039] (2) Raw material composition The first and second surface layers (with identical compositions) consist of: 100 parts by weight of a first PVB resin (weight-average molecular weight 200,000, hydroxyl content 18 mol%, degree of acetylation 3 mol%, degree of acetalization 69 mol%); 30 parts by weight of a first compound plasticizer (DBEA and 3GO, mass ratio 1:5); a UV shielding agent (2-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole); an antioxidant (2,6-di-tert-butyl-p-cresol and tris(2,4-di-tert-butylphenyl) phosphite, mass ratio 2:1); and a metal salt (magnesium acetate and potassium 2-ethylhexanoate, mass ratio 1:2). The surface layer contains 0.5% UV shielding agent, 0.3% antioxidant, and 60 ppm metal salt.

[0040] Intermediate sound insulation layer: 100 parts by weight of second PVB resin (weight average molecular weight 75,000, hydroxyl content 20 mol%, degree of acetylation 8 mol%, degree of acetalization 72 mol%); 70 parts by weight of second compound plasticizer (DBEEA and 3GO, mass ratio 1:2); hindered amine light stabilizer (bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate). The hindered amine light stabilizer in the intermediate sound insulation layer has a mass fraction of 0.3%.

[0041] (3) Preparation Raw material pretreatment: The first and second PVB resins were dried at 90℃ and -0.090MPa for 6 hours. DBEA and 3GO were stirred at 60℃ and 500 rpm for 25 minutes to obtain the first compound plasticizer. DBEA and 3GO were stirred at 65℃ and 600 rpm for 30 minutes to obtain the second compound plasticizer. A hindered amine light stabilizer was added to 3GO (mass ratio of hindered amine light stabilizer to 3GO was 1:8), and dispersed at 25℃ and 2000 rpm for 25 minutes to obtain a stabilizer dispersion.

[0042] Preparation of premixes for each layer: The first PVB resin, the first compound plasticizer, and other additives (UV shielding agent, antioxidant, and metal salt) were mixed at 90°C and 750 rpm for 40 min to obtain the first surface layer premix and the second surface layer premix. The second PVB resin and the second compound plasticizer were mixed at 85°C and 850 rpm for 30 min, and then the stabilizer dispersion was added and the mixture was mixed for another 22 min to obtain the intermediate sound insulation layer premix.

[0043] Melt extrusion, co-extrusion composite: The first and second surface layer premixes were melt-extruded at 175°C, while the middle sound insulation layer premixes were melt-extruded at 165°C. Each melt was then filtered through a 250-mesh metal filter. The filtered melts were then fed into a three-layer co-extrusion die, with the die temperature controlled at 180°C, and distributed through the flow channel to form a three-layer gradient melt film.

[0044] Casting cooling and post-processing: The molten film was cast onto a four-section cooling roller assembly at temperatures of 90℃, 65℃, 45℃, and 30℃, with a traction speed of 1.5 m / min. After cooling, the film was measured for thickness online using laser technology (accuracy ±0.003 mm), and the edges were trimmed to a width of 1.45 m. Then, it was embossed at 50℃ and 0.5 MPa, with a pattern depth of 9 μm. After embossing, the traction tension was controlled at 70 N for winding, with a winding alignment error ≤0.8 mm.

[0045] Aging process: After winding, the membrane material was placed in an environment of 25℃ and 35% relative humidity for 85 hours to obtain a dual-system composite high-damping wide-temperature-range PVB interlayer.

[0046] Example 2 This embodiment provides a dual-system composite high-damping wide-temperature-range PVB interlayer.

[0047] (1) Structural design: The intermediate membrane is a three-layer gradient structure with a total thickness of 0.8 mm. The thickness of the first surface layer and the second surface layer is 0.28 mm, and the thickness of the middle sound insulation layer is 0.24 mm.

[0048] (2) Raw material composition The first and second surface layers (with the same composition) consist of: 100 parts by weight of a first PVB resin (weight-average molecular weight of 210,000, hydroxyl content of 22 mol%, degree of acetylation of 4 mol%, degree of acetalization of 71 mol%); 32 parts by weight of a first compound plasticizer (DBEA and 3GO, mass ratio 1:7); a UV shielding agent (2-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole); an antioxidant (2,6-di-tert-butyl-p-cresol and tris(2,4-di-tert-butylphenyl) phosphite, mass ratio 2:1); and a metal salt (magnesium acetate and potassium 2-ethylhexanoate, mass ratio 1:2). The surface layer contains 0.6% UV shielding agent, 0.35% antioxidant, and 70 ppm metal salt.

[0049] Intermediate sound insulation layer: 100 parts by weight of second PVB resin (weight average molecular weight 80,000, hydroxyl content 23 mol%, degree of acetylation 9 mol%, degree of acetalization 74 mol%); 75 parts by weight of second compound plasticizer (DBEEA and 3GO, mass ratio 1:3); hindered amine light stabilizer (bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate). The hindered amine light stabilizer in the intermediate sound insulation layer has a mass fraction of 0.35%.

[0050] (3) Preparation Raw material pretreatment: The first and second PVB resins were dried at 92℃ and -0.090MPa for 6 hours, respectively. DBEA and 3GO were stirred at 62℃ and 500 rpm for 25 minutes to obtain the first compound plasticizer. DBEA and 3GO were stirred at 68℃ and 600 rpm for 30 minutes to obtain the second compound plasticizer. A hindered amine light stabilizer was added to 3GO (mass ratio of hindered amine light stabilizer to 3GO was 1:8), and dispersed at 25℃ and 2000 rpm for 25 minutes to obtain a stabilizer dispersion.

[0051] Preparation of premixes for each layer: The first PVB resin, the first compound plasticizer, and other additives (UV shielding agent, antioxidant, and metal salt) were mixed at 90°C and 750 rpm for 40 min to obtain the first surface layer premix and the second surface layer premix. The second PVB resin and the second compound plasticizer were mixed at 85°C and 850 rpm for 30 min, and then the stabilizer dispersion was added and the mixture was mixed for another 22 min to obtain the intermediate sound insulation layer premix.

[0052] Melt extrusion, co-extrusion composite: The first and second surface layer premixes are melt-extruded at 180°C, while the middle sound insulation layer premix is ​​melt-extruded at 170°C. Each melt is then filtered through a 250-mesh metal screen. The filtered melt is then conveyed to a three-layer co-extrusion die, with the die temperature controlled at 185°C, and distributed through the flow channel to form a three-layer gradient melt film.

[0053] Casting cooling and post-processing: The molten film was cast onto a four-section cooling roller assembly at temperatures of 92℃, 68℃, 48℃, and 32℃, with a traction speed of 1.8 m / min. After cooling, the film was measured for thickness online using laser technology (accuracy ±0.003 mm) and trimmed to a width of 1.45 m. Then, it was embossed at 52℃ and 0.5 MPa, with a pattern depth of 9 μm. After embossing, the traction tension was controlled at 75 N for winding, with a winding alignment error ≤0.8 mm.

[0054] Aging process: After winding, the membrane material was placed in an environment of 25℃ and 35% relative humidity for 90 hours to obtain a dual-system composite high-damping wide-temperature-range PVB interlayer.

[0055] Example 3 This embodiment provides a dual-system composite high-damping wide-temperature-range PVB interlayer.

[0056] (1) Structural design: The intermediate membrane is a three-layer gradient structure with a total thickness of 1.0 mm. The thickness of the first surface layer and the second surface layer is 0.35 mm, and the thickness of the middle sound insulation layer is 0.3 mm.

[0057] (2) Raw material composition The first and second surface layers (with identical compositions) consist of: 100 parts by weight of a first PVB resin (weight-average molecular weight 220,000, hydroxyl content 20 mol%, degree of acetylation 5 mol%, degree of acetalization 70 mol%); 34 parts by weight of a first compound plasticizer (DBEA and 3GO, mass ratio 1:9); a UV shielding agent (2-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole); an antioxidant (2,6-di-tert-butyl-p-cresol and tris(2,4-di-tert-butylphenyl) phosphite, mass ratio 2:1); and a metal salt (magnesium acetate and potassium 2-ethylhexanoate, mass ratio 1:2). The surface layer contains 0.4% UV shielding agent, 0.25% antioxidant, and 50 ppm metal salt.

[0058] The intermediate sound-insulating layer comprises: 100 parts by weight of a second PVB resin (weight-average molecular weight 85,000, hydroxyl content 24 mol%, degree of acetylation 10 mol%, degree of acetalization 73 mol%); 72 parts by weight of a second compound plasticizer (DBEEA and 3GO, mass ratio 1:2.5); and a hindered amine light stabilizer (bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate). The hindered amine light stabilizer constitutes 0.25% of the intermediate sound-insulating layer by mass.

[0059] (3) Preparation Raw material pretreatment: The first and second PVB resins were dried at 88℃ and -0.090MPa for 6 hours, respectively. DBEA and 3GO were stirred at 58℃ and 500 rpm for 25 minutes to obtain the first compound plasticizer. DBEA and 3GO were stirred at 63℃ and 600 rpm for 30 minutes to obtain the second compound plasticizer. A hindered amine light stabilizer was added to 3GO (mass ratio of hindered amine light stabilizer to 3GO was 1:8), and dispersed at 25℃ and 2000 rpm for 25 minutes to obtain a stabilizer dispersion.

[0060] Preparation of premixes for each layer: The first PVB resin, the first compound plasticizer, and other additives (UV shielding agent, antioxidant, and metal salt) were mixed at 90°C and 750 rpm for 40 min to obtain the first surface layer premix and the second surface layer premix. The second PVB resin and the second compound plasticizer were mixed at 85°C and 850 rpm for 30 min, and then the stabilizer dispersion was added and the mixture was mixed for another 22 min to obtain the intermediate sound insulation layer premix.

[0061] Melt extrusion, co-extrusion composite: The first and second surface layer premixes are melt-extruded at 170°C, while the middle sound insulation layer premix is ​​melt-extruded at 160°C. Each melt is then filtered through a 250-mesh metal screen. The filtered melt is then conveyed to a three-layer co-extrusion die, with the die temperature controlled at 178°C, and distributed through the flow channel to form a three-layer gradient melt film.

[0062] Casting cooling and post-processing: The molten film was cast onto a four-section cooling roller assembly at temperatures of 88℃, 62℃, 42℃, and 28℃, with a traction speed of 2.0 m / min. After cooling, the film was measured for thickness online using laser technology (accuracy ±0.003 mm) and trimmed to a width of 1.45 m. Then, it was embossed at 48℃ and 0.5 MPa, with a pattern depth of 9 μm. After embossing, the traction tension was controlled at 65 N for winding, with a winding alignment error ≤0.8 mm.

[0063] Aging process: After winding, the membrane material was placed in an environment of 25℃ and 35% relative humidity for 82 hours to obtain a dual-system composite high-damping wide-temperature-range PVB interlayer.

[0064] Example 4 This embodiment provides a dual-system composite high-damping wide-temperature-range PVB interlayer.

[0065] (1) Structural design: The intermediate membrane is a three-layer gradient structure with a total thickness of 1.2 mm. The thickness of the first surface layer and the second surface layer is 0.4 mm, and the thickness of the middle sound insulation layer is 0.4 mm.

[0066] (2) Raw material composition The first and second surface layers (with identical compositions) consist of: 100 parts by weight of a first PVB resin (weight-average molecular weight 230,000, hydroxyl content 25 mol%, degree of acetylation 6 mol%, degree of acetalization 73 mol%); 35 parts by weight of a first compound plasticizer (DBEA and 3GO, mass ratio 1:10); a UV shielding agent (2-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole); an antioxidant (2,6-di-tert-butyl-p-cresol and tris(2,4-di-tert-butylphenyl) phosphite, mass ratio 2:1); and a metal salt (magnesium acetate and potassium 2-ethylhexanoate, mass ratio 1:2). The surface layer contains 0.7% UV shielding agent, 0.4% antioxidant, and 80 ppm metal salt.

[0067] The intermediate sound-insulating layer comprises: 100 parts by weight of a second PVB resin (weight-average molecular weight of 90,000, hydroxyl content of 26 mol%, degree of acetylation of 11 mol%, degree of acetalization of 75 mol%); 80 parts by weight of a second compounded plasticizer (DBEEA and 3GO in a mass ratio of 1:4); and a hindered amine light stabilizer (bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate). The hindered amine light stabilizer constitutes 0.4% of the intermediate sound-insulating layer by mass.

[0068] (3) Preparation Raw material pretreatment: The first and second PVB resins were dried at 95℃ and -0.090MPa for 6 hours. DBEA and 3GO were stirred at 65℃ and 500 rpm for 25 minutes to obtain the first compound plasticizer. DBEA and 3GO were stirred at 70℃ and 600 rpm for 30 minutes to obtain the second compound plasticizer. A hindered amine light stabilizer was added to 3GO (mass ratio of hindered amine light stabilizer to 3GO was 1:8), and dispersed at 25℃ and 2000 rpm for 25 minutes to obtain a stabilizer dispersion.

[0069] Preparation of premixes for each layer: The first PVB resin, the first compound plasticizer, and other additives (UV shielding agent, antioxidant, and metal salt) were mixed at 90°C and 750 rpm for 40 min to obtain the first surface layer premix and the second surface layer premix. The second PVB resin and the second compound plasticizer were mixed at 85°C and 850 rpm for 30 min, and then the stabilizer dispersion was added and the mixture was mixed for another 22 min to obtain the intermediate sound insulation layer premix.

[0070] Melt extrusion, co-extrusion composite: The first and second surface layer premixes were melt-extruded at 185°C, while the middle sound insulation layer premixes were melt-extruded at 175°C. Each melt was then filtered through a 250-mesh metal filter. The filtered melts were then fed into a three-layer co-extrusion die, with the die temperature controlled at 190°C, and distributed through the flow channel to form a three-layer gradient melt film.

[0071] Casting cooling and post-processing: The molten film was cast onto a four-section cooling roller assembly at temperatures of 95℃, 70℃, 50℃, and 35℃, with a traction speed of 2.5 m / min. After cooling, the film was measured for thickness online using laser technology (accuracy ±0.003 mm) and trimmed to a width of 1.45 m. Then, it was embossed at 55℃ and 0.5 MPa, with a pattern depth of 9 μm. After embossing, the traction tension was controlled at 90 N for winding, with a winding alignment error ≤0.8 mm.

[0072] Aging process: After winding, the membrane material was placed in an environment of 25℃ and 35% relative humidity for 96 hours to obtain a dual-system composite high-damping wide-temperature-range PVB interlayer.

[0073] Example 5 This embodiment provides a dual-system composite high-damping wide-temperature-range PVB interlayer.

[0074] (1) Structural design: The intermediate membrane is a three-layer gradient structure with a total thickness of 0.9 mm. The thickness of the first surface layer and the second surface layer is 0.3 mm, and the thickness of the middle sound insulation layer is 0.3 mm.

[0075] (2) Raw material composition The first and second surface layers (with identical compositions) consist of: 100 parts by weight of a first PVB resin (weight-average molecular weight 205,000, hydroxyl content 16 mol%, degree of acetylation 2 mol%, degree of acetalization 68 mol%); 28 parts by weight of a first compound plasticizer (DBEA and 3GO, mass ratio 1:4); a UV shielding agent (2-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole); an antioxidant (2,6-di-tert-butyl-p-cresol and tris(2,4-di-tert-butylphenyl) phosphite, mass ratio 2:1); and a metal salt (magnesium acetate and potassium 2-ethylhexanoate, mass ratio 1:2). The surface layer contains 0.55% UV shielding agent, 0.3% antioxidant, and 65 ppm metal salt.

[0076] The intermediate sound-insulating layer comprises: 100 parts by weight of a second PVB resin (weight-average molecular weight 78,000, hydroxyl content 18 mol%, degree of acetylation 7 mol%, degree of acetalization 71 mol%); 65 parts by weight of a second compounded plasticizer (DBEEA and 3GO, mass ratio 1:1.5); and a hindered amine light stabilizer (bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate). The hindered amine light stabilizer constitutes 0.3% of the intermediate sound-insulating layer by mass.

[0077] (3) Preparation Raw material pretreatment: The first and second PVB resins were dried at 91℃ and -0.090MPa for 6 hours, respectively. DBEA and 3GO were stirred at 55℃ and 500 rpm for 25 minutes to obtain the first compound plasticizer. DBEA and 3GO were stirred at 60℃ and 600 rpm for 30 minutes to obtain the second compound plasticizer. A hindered amine light stabilizer was added to 3GO (mass ratio of hindered amine light stabilizer to 3GO was 1:8), and dispersed at 25℃ and 2000 rpm for 25 minutes to obtain a stabilizer dispersion.

[0078] Preparation of premixes for each layer: The first PVB resin, the first compound plasticizer, and other additives (UV shielding agent, antioxidant, and metal salt) were mixed at 90°C and 750 rpm for 40 min to obtain the first surface layer premix and the second surface layer premix. The second PVB resin and the second compound plasticizer were mixed at 85°C and 850 rpm for 30 min, and then the stabilizer dispersion was added and the mixture was mixed for another 22 min to obtain the intermediate sound insulation layer premix.

[0079] Melt extrusion, co-extrusion composite: The first and second surface layer premixes were melt-extruded at 172°C, while the middle sound insulation layer premixes were melt-extruded at 162°C. Each melt was then filtered through a 250-mesh metal screen. The filtered melts were then fed into a three-layer co-extrusion die, with the die temperature controlled at 182°C, and distributed through the flow channel to form a three-layer gradient melt film.

[0080] Casting cooling and post-processing: The molten film was cast onto a four-section cooling roller assembly at temperatures of 91℃, 66℃, 46℃, and 31℃, with a traction speed of 1.7 m / min. After cooling, the film was measured online using laser thickness measurement (accuracy ±0.003 mm) and trimmed to a width of 1.45 m. Then, it was embossed at 49℃ and 0.5 MPa, with a pattern depth of 9 μm. After embossing, the traction tension was controlled at 68 N for winding, with a winding alignment error ≤0.8 mm.

[0081] Aging process: After winding, the membrane material was placed in an environment of 25℃ and 35% relative humidity for 88 hours to obtain a dual-system composite high-damping wide-temperature-range PVB interlayer.

[0082] Comparative Example 1 This comparative example provides a PVB interlayer film, which differs from Example 2 only in that the first compound plasticizer is modified to a single 3GO (32 parts by weight), and the second compound plasticizer is modified to a single 3GO (75 parts by weight).

[0083] Comparative Example 2 This comparative example provides a PVB interlayer film, which differs from Example 2 only in that: the first compound plasticizer is modified to DBEEA and 3GO in a mass ratio of 1:3 (32 parts by weight), and the second compound plasticizer is modified to DBEA and 3GO in a mass ratio of 1:7 (75 parts by weight).

[0084] Comparative Example 3 This comparative example provides a PVB interlayer film, which differs from Example 2 only in that the second compound plasticizer is modified to DBEA and 3GO, with a mass ratio of 1:7 (75 parts by weight).

[0085] Experimental Example 1 The intermediate films prepared in Examples 1-5 and Comparative Examples 1-3 were respectively made into laminated glass, and the specific steps are as follows: The first glass substrate, the intermediate film, and the second glass substrate are sequentially stacked and placed in a vacuum laminator for pre-pressing at 100°C and -0.095MPa for 40 minutes. The pre-pressed composite is then transferred to an autoclave and subjected to high-temperature and high-pressure pressing at 135°C and 1.45MPa for 85 minutes to form a strong and dense bond between the intermediate film and the glass substrate, thereby obtaining the laminated glass.

[0086] The following performance tests were performed on the obtained laminated glass and interlayer: (1) First light irradiation test: Four cycles of test were conducted according to the method described in patent CN110352181A, and the void state at the end of the intermediate film was observed and recorded. The test conditions were as follows: after irradiating xenon light for 144 hours at a black panel temperature of 83℃, a tank temperature of 50℃, and a humidity of 50%RH, the film was immersed in pure water at 80℃ for 24 hours, and then dried at 23℃ and 50% humidity for 4 hours. This constituted one cycle; the xenon light irradiance was 180W / m². 2 (Wavelength 300~400nm), using an internal quartz filter and an external quartz #275 filter (cutoff value 275nm); when the visible light transmittance of the two glass plates is the same, irradiation is performed from the side of the first glass plate, and when they are different, irradiation is performed from the side with higher transmittance.

[0087] (2) Visible light transmittance: measured in the wavelength range of 380~780nm according to JIS R3211:1998 standard.

[0088] (3) Bond strength: Tested according to GB / T 14683-2017 standard.

[0089] (4) Plasticizer migration rate: After the intermediate film is aged in an environment of 80°C for 1000 hours, the residual amount of plasticizer on the surface is measured and the migration rate is calculated.

[0090] (5) Low temperature flexibility: After the intermediate film is kept at -40℃ for 2 hours, a 180° bending test is performed to observe whether it cracks.

[0091] (6) Wide temperature range sound insulation performance: According to GB / T 18696.2-2002 standard, the sound insulation of 315Hz frequency at -40℃, 25℃ and 80℃ is tested respectively, and its fluctuation value is calculated.

[0092] The results of the basic performance tests are recorded in Table 1, and the results of the wide temperature range sound insulation performance tests are recorded in Table 2.

[0093] Table 1 Basic performance test results

[0094] Table 2. Test results of sound insulation performance over a wide temperature range

[0095] As shown in Tables 1 and 2, the dual-system composite high-damping wide-temperature-range PVB interlayer provided by this invention exhibits excellent comprehensive performance in comprehensive performance tests. Test results show that the interlayer maintains a sound insulation level above 42 dB at 315 Hz within a wide temperature range of -40℃ to 80℃, with a sound insulation fluctuation of no more than 1.0 dB, demonstrating its excellent wide-temperature-range acoustic stability. Simultaneously, the interlayer shows no cracks when bent 180° at -40℃, exhibiting excellent low-temperature flexibility and resistance to brittle fracture; after aging at 80℃ for 1000 hours, the plasticizer migration rate is as low as 1.5~1.9%, demonstrating excellent migration resistance and long-term thermal stability. Furthermore, its adhesion strength to glass reaches over 27 N / cm, and after a rigorous first light irradiation test, the interface voids are extremely small (≤0.5 mm), with a visible light transmittance higher than 88%, meeting the application requirements in extreme environments. Performance comparison with comparative examples further verifies the unique advantages of the dual-system composite and gradient structure design of this invention. Compared to a single plasticizer system (Comparative Example 1), this invention significantly improves sound insulation performance, low-temperature toughness, plasticizer stability, and interfacial durability. Compared to a compound system with the formula reversed (Comparative Example 2) or a compound system using only a single amine (Comparative Example 3), this invention precisely matches the layer functional requirements of the "DBEA / 3GO surface layer (enhancing adhesion and low-temperature toughness)" and the "DBEEA / 3GO intermediate layer (broadening the damping temperature range and sound insulation stability)," resulting in a more balanced and superior performance in terms of wide-temperature-range sound insulation stability, plasticizer migration inhibition, and interfacial reliability. This breakthrough overcomes the technical bottleneck of insufficient performance of traditional PVB interlayer films under extreme temperature environments.

[0096] Therefore, this invention employs the above-mentioned dual-system composite high-damping wide-temperature-range PVB interlayer film and its preparation method with laminated glass. By constructing a "DBEA / 3GO (surface layer) + DBEEA / 3GO (interlayer)" dual-composite plasticizing system and precisely matching it with a three-layer gradient structure, a synergistic improvement of multiple properties under a wide temperature range is achieved.

[0097] Finally, it should be noted that the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A dual-system composite high-damping wide-temperature-range PVB interlayer, characterized in that, The intermediate membrane has a three-layer gradient structure, consisting of a first surface layer, a middle sound-insulating layer, and a second surface layer from the outside to the inside. Both the first surface layer and the second surface layer contain a first PVB resin and a first compound plasticizer, wherein the first compound plasticizer includes dibutoxyethyl adipate and triethylene glycol di-2-ethylhexanoate; The intermediate sound insulation layer comprises a second PVB resin and a second compound plasticizer, wherein the second compound plasticizer comprises di(butoxyethoxyethyl) adipic acid and triethylene glycol di-2-ethylhexanoate.

2. The dual-system composite high-damping wide-temperature-range PVB interlayer according to claim 1, characterized in that, In the first compound plasticizer, the mass ratio of dibutoxyethyl adipate to triethylene glycol di-2-ethylhexanoate is 1:(4~10); the mass ratio of the first PVB resin to the first compound plasticizer is 100:(28~35).

3. The dual-system composite high-damping wide-temperature-range PVB interlayer according to claim 1, characterized in that, In the second compound plasticizer, the mass ratio of adipate di(butoxyethoxyethyl) ester and triethylene glycol di-2-ethylhexanoate is 1:(1.5~4); the mass ratio of the second PVB resin and the second compound plasticizer is 100:(65~80).

4. The dual-system composite high-damping wide-temperature-range PVB interlayer according to claim 1, characterized in that, The first PVB resin has a weight-average molecular weight of 190,000 to 230,000 and a hydroxyl content of 12 to 28 mol; the second PVB resin has a weight-average molecular weight of 70,000 to 90,000 and a hydroxyl content of 15 to 27 mol.

5. The dual-system composite high-damping wide-temperature-range PVB interlayer according to claim 1, characterized in that, The first and second surface layers also contain an ultraviolet shielding agent, an antioxidant, and a metal salt, respectively; the intermediate sound-insulating layer also contains a hindered amine light stabilizer.

6. The dual-system composite high-damping wide-temperature-range PVB interlayer according to claim 1, characterized in that, The thickness ratio of the first surface layer, the intermediate sound insulation layer, and the second surface layer is (30~40):(20~40):(30~40); the total thickness of the intermediate film is 0.5~1.2mm.

7. A method for preparing a dual-system composite high-damping wide-temperature-range PVB interlayer as described in any one of claims 1 to 6, characterized in that, Includes the following steps: S1. Prepare the first surface layer premix, the middle sound insulation layer premix, and the second surface layer premix respectively; S2. The first surface layer premix, the middle sound insulation layer premix, and the second surface layer premix are melt-extruded and co-extruded to form a melt film. S3. The molten film is sequentially subjected to casting, cooling, and curing treatments to obtain the dual-system composite high-damping wide-temperature-range PVB interlayer film.

8. The method according to claim 7, characterized in that, In S2, the melt extrusion temperatures of the first surface layer premix and the second surface layer premix are 165~185℃, respectively; the melt extrusion temperature of the intermediate sound insulation layer premix is ​​155~175℃.

9. The method according to claim 7, characterized in that, In S3, the aging process is carried out at a temperature of 20-30°C, a relative humidity of 30-40%, and a time of 80-96 hours.

10. A laminated glass, characterized in that, It includes two glass substrates arranged opposite each other, and a dual-system composite high-damping wide-temperature-range PVB interlayer as described in any one of claims 1 to 6 sandwiched between the two glass substrates.

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