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CN-115881873-B - High-light-transmittance low-moisture-absorption material for LED packaging and preparation method thereof

CN115881873BCN 115881873 BCN115881873 BCN 115881873BCN-115881873-B

Abstract

The invention provides a high-light-transmittance low-moisture-absorption material for LED packaging, which is prepared by grafting and modifying a collagen polypeptide single-layer film G-STSocac by using epoxy polysiloxane (PDMS-E) with a molecular weight of 1000, wherein the grafting rate of the epoxy polysiloxane on the film is 1.7-2.0%, the contact angle is 115-126 ℃, the water resistance is that the weight loss rate of the epoxy polysiloxane after being soaked in water for 2 hours is 0.006-0.011%, the high temperature resistance is that the weight loss rate of the epoxy polysiloxane after being stood for 2 hours is 0.002-0.005% under the condition of 150+/-5 ℃, and the visible light transmittance is 94-98%. The high-light-transmittance low-moisture-absorption material for LED packaging provided by the invention has good light transmittance characteristics, low thickness and controllability, and the epoxy polysiloxane is firmly combined with the polypeptide monolayer film, so that the chemical stability is high. Compared with the prior art, the coating can improve the adhesiveness of the coating on the surface of the material.

Inventors

  • LI TIANDUO
  • XU JING
  • BAN QING
  • GAO CHUNHONG
  • XING LEI
  • SONG HONGYANG

Assignees

  • 齐鲁工业大学

Dates

Publication Date
20260512
Application Date
20210927

Claims (8)

  1. 1. A high-light-transmittance low-moisture-absorption material for LED packaging is characterized in that epoxy polysiloxane (PDMS-E) with a molecular weight of 1000 is used for grafting modification of a collagen polypeptide single-layer film G-STSocac, wherein the grafting rate of the epoxy polysiloxane on the film is 1.7-2.0%, the contact angle is 115-126 DEG, the water resistance is that the weight loss rate after being soaked in water for 2 hours is 0.006-0.011%, the high-temperature resistance is that the weight loss rate after being stood for 2 hours is 0.002-0.005% under the condition of 150+/-5 ℃, and the visible light transmittance is 94-98%; The collagen polypeptide single-layer film G-STSocac is composed of polypeptide molecules with the molecular weight of (1.48+/-0.2) multiplied by 10 5 G/mol, the thickness of the single-layer film is 8.5nm, the exposure of primary amino on the surface of the film is 11.60%, the Zeta potential of the polypeptide single-layer film is-8.75 mV, the contact angle of the film is 61 degrees, the secondary structure of the collagen polypeptide single-layer film G-STSocac is 29.66 +/-0.1% of alpha-helix, 18.98+/-0.15% of beta-sheet, 7.93+/-0.05% of beta-turn, and 43.44+/-0.26% of random coil; the grafting ratio is defined as follows: The change of the molar quantity of the primary amino groups on the membrane before and after the grafting reaction accounts for the percentage of the molar quantity of the primary amino groups on the membrane before the grafting reaction; the change of the molar quantity of the primary amino groups on the membrane before and after the grafting reaction is calculated by (W D -W 0 )/1000, namely the molar quantity of the epoxy polysiloxane successfully grafted, wherein W D is the mass of the polypeptide monolayer membrane after the epoxy polysiloxane is grafted, and W 0 is the mass of the polypeptide monolayer membrane before the epoxy polysiloxane is grafted; The molecular formula of the epoxy polysiloxane is shown as follows: 。
  2. 2. The material of claim 1, wherein the wavelength of visible light is 780-400 nm.
  3. 3. The material according to claim 1, wherein the preparation method of the polypeptide monolayer film G-STSocac comprises the following steps: (1) Preparing a polypeptide solution at 50 ℃, then adding surfactant sodium tetradecyl sulfonate STSo to obtain a polypeptide-STSo mixed solution with STSo concentration of 2.5mmol/L, and preserving heat for later use; (2) Immersing a substrate material into a mixed acid solution for treatment, flushing to neutrality, drying by using nitrogen, and then drying; (3) Immersing the dried substrate material into a polyethyleneimine PEI aqueous solution for treatment, washing with water, drying by blowing nitrogen, and drying to obtain a PEI-deposited positive ionization substrate material; (4) Immersing the positively ionized substrate material into the polypeptide-STSo mixed solution obtained in the step (1), depositing for 8-12 min, then pulling the substrate material in deionized water for 20-25 times, and drying the substrate material by high-purity nitrogen to obtain the polypeptide single-layer film G-STSocac.
  4. 4. A material according to claim 3, wherein the substrate material in step (2) is metal, rubber or glass.
  5. 5. The material of claim 4, wherein the substrate material is a glass sheet.
  6. 6. The method for preparing the high-light-transmittance low-moisture-absorption material for LED packaging according to any one of claims 1 to 5, which is characterized by comprising the following steps: 1) Adding epoxy polysiloxane with molecular weight of 1000 into sodium carbonate-sodium bicarbonate buffer solution, and performing ultrasonic dispersion to obtain a mixed solution; 2) Placing the collagen polypeptide monolayer film G-STSocac in the mixed solution obtained in the step 1) for 1-3 hours at 48-52 ℃; 3) And (3) extracting the collagen polypeptide single-layer film G-STSocac treated in the step (2) in acetone for multiple times to remove unreacted epoxy polysiloxane, drying by high-purity nitrogen, and then placing in nitrogen for preservation.
  7. 7. The method according to claim 6, wherein the sodium carbonate-sodium bicarbonate buffer in step 1) has a pH of 9.6.
  8. 8. The preparation method according to claim 6, wherein the concentration of the epoxy polysiloxane in the mixed solution in the step 1) is 0.009-0.02 mol/L.

Description

High-light-transmittance low-moisture-absorption material for LED packaging and preparation method thereof Technical Field The invention belongs to the field of LED packaging materials, and particularly relates to a high-light-transmittance low-moisture-absorption material for LED packaging and a preparation method thereof. Background China is a large country of LED packaging, and 80% of LED device packaging is concentrated in China according to statistics, and the LED device packaging is distributed in various kinds of beauty resource, table resource, hongKong-funded and interior resource packaging enterprises respectively. However, the research of the LED packaging materials in China is far behind the main countries such as the United states and Japan, and the market of the power type LED packaging materials is fully occupied by Japanese and American products, so that the cost of the products is increased, the profit margin is small, and more importantly, the development is severely restricted. The power type LED has high requirements on sealing performance and light transmittance of the packaging material, has the highest requirements on refractive index and cohesiveness, and has certain low dielectric property, mechanical property and the like. At present, the main common packaging materials in the market in China are epoxy resin, polycarbonate, polymethyl methacrylate, glass, organic silicon and the like, and among the high-transparency materials, the polymethyl methacrylate, the polycarbonate and the glass are mainly used as outer-layer lens materials, and the epoxy resin and the organic silicon materials can be used as packaging materials and also can be used as lens materials. The packaging schematic diagram (as shown in fig. 1) of the LED chip is that the bonding glue plays a role of the LED packaging material, is positioned at the upper part of the LED chip, is completely coated on the chip, and plays a role of protecting the chip and relieving vibration brought by the outside. Therefore, the LED package requires an encapsulation material having a refractive index as high as possible, good light transmittance, strong adhesion, a certain hardness, excellent mechanical properties, and the like. The epoxy resin is used as a packaging material, and has certain hygroscopicity, high crosslinking density after curing, high brittleness, high internal stress, poor impact resistance and the like. Barton et al (white light LED aging mechanism research progress [ J ]. Foreign electronic components, 2007, (1) 8:121) research finds that the temperature range of 135-145 ℃ also causes serious degradation of resin, and the transparency of epoxy resin is obviously reduced at about 150 ℃, so that the LED light output is obviously weakened, and the service life of the LED device is seriously influenced. Under the condition of large current passing, the epoxy resin is even carbonized as an encapsulating material, and a conductive channel is formed on the surface of the LED device, so that the device is disabled, and the use of the epoxy resin is greatly limited. The reaction of the polydimethylsiloxane in the Chinese patent document US5561174 introduces active end groups or side groups into the epoxy resin, the heat resistance, the internal stress and the shock resistance of the epoxy resin are obviously improved, and the epoxy resin can be modified to improve some defects of the epoxy resin serving as an LED packaging material, but the development requirement of an LED can not be met. Particularly, with the development of power LEDs, the requirements for the packaging materials are increasing, so that new packaging materials with high refractive index and high transparency are urgently required to be developed to meet the market demands. The organic silicon material has high light transmittance, good thermal stability, strong ultraviolet light resistance, small internal stress and low hygroscopicity, so the organic silicon material is greatly valued in recent years as a new generation power type LED packaging material. However, when the organic silicon material is used for preparing the packaging material coating in the prior art, the obtained film thickness is thicker, the coating is easy to crack, the coating firmness is poor, the thickness is not easy to control, and the like. Disclosure of Invention In order to solve the problems in the prior art, the invention provides a high-light-transmittance low-moisture-absorption material for LED packaging and a preparation method thereof. In order to achieve the above purpose, the present invention adopts the following technical scheme: A high-light-transmittance low-moisture-absorption material for LED packaging is characterized in that epoxy polysiloxane (PDMS-E) with a molecular weight of 1000 is used for grafting modification of a collagen polypeptide single-layer film G-STSocac, the grafting rate of the epoxy polysiloxane on the film is 1.7-2.0%, the contact angle is