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CN-122008675-A - Multilayer-structure high-impact TPU glass interlayer film and preparation method thereof

CN122008675ACN 122008675 ACN122008675 ACN 122008675ACN-122008675-A

Abstract

The invention belongs to the technical field of TPU glass sandwich films, and discloses a high-impact TPU glass sandwich film with a multilayer structure and a preparation method thereof. The sandwich film has a symmetrical three-layer structure, and comprises a core layer and two skin layers, wherein the core layer consists of aliphatic polyether type thermoplastic polyurethane, the two skin layers consist of aliphatic polycaprolactone type thermoplastic polyurethane, the hardness of the skin layers is higher than that of the core layer, the thickness ratio of the core layer to the skin layers is 1.50-4:1, the total light transmittance of the sandwich film is more than or equal to 91%, and the haze is less than or equal to 1.0%. The high-impact TPU glass sandwich film with the multilayer structure can meet the lamination requirements of interlayers such as glass, PC, PMMA and the like. The TPU interlayer film has higher stretch resistance and puncture resistance, and endows laminated glass, laminated explosion-proof glass and the like with excellent impact resistance and explosion resistance. Meanwhile, the glass has better optical light transmittance and long-term aging resistance.

Inventors

  • An Xupeng
  • HU XIAOYUE

Assignees

  • 浙江环龙新材料科技有限公司

Dates

Publication Date
20260512
Application Date
20260320

Claims (10)

  1. 1. The high impact TPU glass sandwich film with the multilayer structure is of a symmetrical three-layer structure and is characterized by comprising a core layer (1) and two skin layers (2), wherein the core layer is composed of aliphatic polyether type thermoplastic polyurethane, the two skin layers (2) are composed of aliphatic polycaprolactone type thermoplastic polyurethane, the hardness of the skin layers (2) is higher than that of the core layer (1), the thickness ratio of the core layer (1) to the skin layers (2) is 1.50-4:1, the total light transmittance of the sandwich film is more than or equal to 91%, and the haze is less than or equal to 1.0%.
  2. 2. The multilayer structure high impact TPU glass interlayer film according to claim 1, wherein the core layer (1) comprises 40-80 parts by mass of polytetrahydrofuran ether glycol, 20-40 parts by mass of aliphatic diisocyanate, 5-15 parts by mass of dihydric alcohol chain extender, 0.1-0.5 part by mass of stannous octoate as a main catalyst and 0.05-0.25 part by mass of dibutyltin dilaurate.
  3. 3. The multilayer structure high impact TPU glass interlayer film of claim 2, wherein the Mn of polytetrahydrofuran ether glycol is 1000-3000, and the dihydric alcohol chain extender is one or more of 1, 4-butanediol, ethylene glycol, 1, 6-hexanediol and silane chain extender.
  4. 4. The multilayer structure high impact TPU glass interlayer film according to claim 2, wherein the R value of the core layer (1) is controlled to be 0.95-1.05, and the hard segment content is controlled to be 20% -35%.
  5. 5. The multilayer structure high impact TPU glass interlayer film according to claim 1, wherein the composition of the skin layer (2) comprises, by mass, 30-65 parts of poly epsilon-caprolactone diol, 30-45 parts of hexamethylene diisocyanate, 5-15 parts of 1, 4-butanediol, 0.5-3 parts of a silane coupling agent, 0.1-0.5 part of a UV622 auxiliary agent, 0.1-0.5 part of a UV329 auxiliary agent, 0.1-0.5 part of stannous octoate as a main catalyst, and 0.1-0.5 part of dibutyltin dilaurate.
  6. 6. The high impact TPU glass interlayer film of claim 5 wherein the poly epsilon-caprolactone diol has a Mn of 1500 to 2000.
  7. 7. The high impact TPU glass interlayer film of claim 2 or 5 wherein the aliphatic diisocyanate comprises hexamethylene diisocyanate and isophorone diisocyanate.
  8. 8. The high impact TPU glass interlayer film of claim 5 wherein the silane coupling agent is bis- (gamma-hydroxypropyl) dimethylsilane.
  9. 9. The multilayer structure high impact TPU glass interlayer film according to claim 5, wherein the R value of the skin layer (2) is controlled to be 1.02-1.10, and the hard segment content is controlled to be 30% -45%.
  10. 10. A method for preparing a high impact TPU glass interlayer film with a multilayer structure according to any one of claims 1 to 9, comprising the steps of: Synthesizing core layer and skin layer TPU granules by adopting a bulk prepolymerization-chain extension method or a one-step method respectively, synthesizing the core layer and the skin layer TPU under the protection of inert gas, granulating under water, drying to obtain transparent TPU granules, and drying the core layer and the skin layer TPU granules at 80-100 ℃ for 4-6 hours respectively; Putting core layer granules into a main extruder, putting skin layer granules into two auxiliary extruders, accurately controlling the temperature of each extruder to be 150-190 ℃, pumping and metering the melt, compounding in a three-layer co-extrusion die head, casting the three-layer co-extrusion melt through a T-shaped die head onto a mirror cooling roller with the surface temperature controlled to be 10-30 ℃, and rapidly cooling and shaping. The film surface is subjected to an in-line corona treatment to further activate the surface, followed by winding with a separator film.

Description

Multilayer-structure high-impact TPU glass interlayer film and preparation method thereof Technical Field The invention belongs to the technical field of TPU glass sandwich films, and particularly relates to a high-impact TPU glass sandwich film with a multilayer structure and a preparation method thereof. Background High performance laminated glass interlayer films are evolving toward a combination of ultra-high definition optical properties, long-term weatherability, excellent safety and environmental suitability. The traditional PVB film has the defects of weather resistance (yellowing), tear resistance and wide-temperature-range mechanical property stability. Although a single TPU film has advantages in toughness and temperature resistance, the contradiction between high light transmittance and impact resistance is difficult to balance, a phase separation structure or an additive is often required to be introduced to improve the impact resistance, optical uniformity is possibly damaged, haze is increased, the contradiction between hydrolysis resistance and ultraviolet aging resistance is excellent, the polyether TPU film has excellent hydrolysis resistance, ether bonds are easy to oxidize under ultraviolet light to cause yellowing, the polyester TPU film (such as polycaprolactone type) has high mechanical strength and relatively good ultraviolet resistance, the ester bonds are easy to hydrolyze, and the contradiction between the polymerization strength in the film layer and the bonding strength of a glass interface is difficult to optimize the body performance and the interface performance simultaneously. Disclosure of Invention The invention aims to overcome the defects in the prior art, and provides a high-impact TPU glass interlayer film with a multilayer structure and a preparation method thereof through the hardness design of material components in the TPU synthesis stage. Through polymer molecular design, respectively synthesizing aliphatic polyether type TPU (core layer A) and aliphatic polycaprolactone type TPU (skin layer B) with specific chemical structures, and compounding through a coextrusion process, the characteristics of high elasticity and water desorption resistance of a core layer main body and high strength, strong adhesion and weather resistance protection of a skin layer main body are realized. The specific technical scheme is as follows: A high-impact TPU glass sandwich film with a multilayer structure is of a symmetrical three-layer structure, and comprises a core layer, two skin layers and a two-layer sandwich film, wherein the core layer is composed of aliphatic polyether type thermoplastic polyurethane, the two skin layers are composed of aliphatic polycaprolactone type thermoplastic polyurethane, the hardness of the skin layers is higher than that of the core layer, the thickness ratio of the core layer to the skin layers is 1.50-4:1, the total light transmittance of the sandwich film is more than or equal to 91%, and the haze is less than or equal to 1.0%. Further, the core layer comprises, by mass, 40-80 parts of polytetrahydrofuran ether glycol, 20-40 parts of aliphatic diisocyanate, 5-15 parts of dihydric alcohol chain extender, and 0.1-0.5 part of stannous octoate serving as a main catalyst, wherein the addition amount of the main catalyst is 0.05-0.25 part of dibutyltin dilaurate. Further, the Mn of the polytetrahydrofuran ether glycol is 1000-3000, and the dihydric alcohol chain extender adopts one or more of 1, 4-butanediol, ethylene glycol, 1, 6-hexanediol and silane chain extender. Further, the R value of the core layer (1) is controlled to be 0.95-1.05, and the hard segment content is controlled to be 20% -35%. Further, the skin layer (2) comprises, by mass, 30-65 parts of poly epsilon-caprolactone diol, 30-45 parts of hexamethylene diisocyanate, 5-15 parts of 1, 4-butanediol, 0.5-3 parts of a silane coupling agent, 0.1-0.5 part of a UV622 auxiliary agent, 0.1-0.5 part of a UV329 auxiliary agent, 0.1-0.5 part of stannous octoate serving as a main catalyst, and 0.1-0.5 part of dibutyltin dilaurate. Further, the Mn of the poly epsilon-caprolactone diol is 1500-2000. Further, the aliphatic diisocyanate comprises hexamethylene diisocyanate and isophorone diisocyanate. Further, the silane coupling agent is bis- (gamma-hydroxypropyl) dimethylsilane. Further, the R value of the cortex (2) is controlled to be 1.02-1.10, and the hard segment content is controlled to be 30% -45%. The preparation method of the multilayer structure high impact TPU glass interlayer film comprises the following steps: Synthesizing core layer and skin layer TPU granules by adopting a bulk prepolymerization-chain extension method or a one-step method respectively, synthesizing the core layer and the skin layer TPU under the protection of inert gas, granulating under water, drying to obtain transparent TPU granules, and drying the core layer and the skin layer TPU granules at 80-100 ℃ for 4-6 hours