The Preparation And Application Of UV-Curable Monomers And Oligomers Used In Brightness Enhancement Films Of LCD

In this dissertation, a series of acrylate monomers containing fluorene (or bisphenol A) and a series of acrylate oligomers containing fluorene both with good application prospects in the field of UV curing were designed and synthesized. FT-IR and NMR were used to characterize the structures of those monomers and oligomers. Besides, they were characterized with the tests of solvent content, viscosity, refractive index et al. One-factor experiment was designed to optimize the monomers’mol ratio of reactants and the concentration of NaOH using for neutralization. At the same time, the monomers and oligomers were respectively used in the formulations of UV-curable glue. These resulting BEFs were characterized with the tests of adhesion, scratch resistance, abrasion resistance, rebound time et al.Firstly, BPAIOEODA as a UV-curable monomer applied in liquid crystal display was successfully synthesized by esterification reaction of ethoxylated bisphenol A (BPA10EO) and acrylate acid (AA) under mild conditions. BPEA containing fluorene with high refractive index was successfully synthesized by esterification reaction of fluorene-9-bisphenol (BPEF) and acrylate acid (AA) under mild conditions. As to BPAIOEODA, the suitable mol ratio of carboxyl (-COOH) and hydroxyl (-OH) groups was 1.25, and the optimum concentration of NaOH using for neutralization was 10 wt.%. As to BPEA, the suitable mol ratio of carboxyl (-COOH) and hydroxyl (-OH) groups was 3.2, and the optimum concentration of NaOH using for neutralization was 15 wt.%. After 15 times’ repetitions, the process and properties of those monomers were stable and reliable. The resulting BPAIOEODA exhibited low solvent content (≤800 ppm), low viscosity (500-800 mPa-s at 25℃), and high refractive index (1.5170±0.005 at 20℃). The resulting BPEA exhibited low solvent content (<1200 ppm), low viscosity (44000-56000 mPas at 25 ℃), and high refractive index (1.62±0.01 at 20℃). BPAIOEODA was brought from the lab to pilot scale in the reactor of 300L. The performance of the pilot product was stable, and reached the quality requirements for products in industrial production line.The coating formulations of 1.54 QQ UV-curable glue were mixed with the lab product and pilot product of BPAIOEODA as reactive diluents respectively. Though the technology of UV-curing forming, the corresponding brightness enhancement films (BEFs) were obtained. The resulting films both exhibited normal structure, excellent adhesion (5B), good scratch resistance (50 g), good abrasion resistance (100 g), short rebound time (<6 s). They showed excellent performance, and have reached the quality standard for use in LCD industry. The coating formulations of 1.57 UV-curable glue were mixed with BPEA as reactive diluents. Though the technology of UV-curing forming, the corresponding brightness enhancement films (BEFs) were obtained. The resulting films exhibited normal structure, excellent adhesion (5B), good scratch resistance (50 g), good abrasion resistance (50 g). They showed excellent performance.Secondly, BPEFPAA containing fluorene as a UV-curing polyester acrylate oligomer with high refractive index was synthesized by a two-step esterification reaction. BPEFPGMA containing fluorene as a UV-curing epoxy acrylate oligomer with high refractive index was synthesized though semi-esterification reaction of fluorene-9-bisphenol (BPEF) and phthalic anhydride (PA), followed by end-caping of glycidyl methacrylate (GMA). After 15 times’ repetitions, the process and properties of those oligomers were stable and reliable. The resulting BPEFPAA exhibited low solvent content (<1700 ppm), low viscosity (1900-4500 mPa-s at 60℃), high refractive index (1.587±0.007 at 20℃), and normal Mw (2550-3536 g/mol). The resulting BPEFPGMA exhibited low solvent content (≤1600 ppm), low viscosity (1900-2500 mPa-s at 60℃), high refractive index (1.587± 0.003 at 20℃), and normal Mw (2550-3536 g/mol).The coating formulations of 1.57 UV-curable glue were mixed with the BPEFPAA and BPEFPGMA as reactive oligomer respectively. Though the technology of UV-curing forming, the corresponding brightness enhancement films (BEFs) were obtained. The resulting films both exhibited normal structure, excellent adhesion (5B), good scratch resistance (50 g), good abrasion resistance (50 g). They showed excellent performance, and have reached the quality standard for use in LCD industry.