Facile Preparation of a Macromolecular Benzophenone Photoinitiator

Liu

et al. 2023

Preprint

A series of new benzophenone derivatives were synthesized by the esterification reaction of hydroxy-benzophenone and acyl chloride or sulfonyl chloride. All the compounds were characterization by NMR and MS spectroscopy technology. The resulting products exhibited efficient UV light absorption in the range of 225–325 nm, leading to excellent photoinitiating effects as photoinitiators in light-cured coatings. The cured film showed comparable mechanical performance with the commercial product. Moreover, we discussed the photoinitiation mechanism of the new benzophenone derivatives, which would promote the further development of novel photoinitiators for industry application.

Section: Introductionmentioning

confidence: 99%

Synthesis and application of novel benzophenone photoinitiators

Cao

Liu

et al. 2023

Preprint

“…This novel compound exhibits excellent migration stability and photoinitiation efficiency, making it a promising candidate for future application in 3D printing. Huang and co‐workers [9] synthesized a polyurethane‐based macromolecular BP photoinitiator by combining hydroxyl‐containing Michler's ketone with toluene diisocyanate (TDI). Telitel and co‐workers [10] designed six benzopyrene substitutes and three thiophene‐pyridinium salt structures based on the structure of benzophenone, and tested the photoreactivity of acrylate and epoxy resins under ultraviolet irradiation.…”

Section: Introductionmentioning

confidence: 99%

Synthesis and Application of New Benzophenone Photoinitiators

Feng,

Wang,

Liu

et al. 2023

ChemistrySelect

A series of new benzophenone derivatives were synthesized by the esterification reaction of hydroxy‐benzophenone and acyl chloride or sulfonyl chloride. All the compounds were characterization by NMR and MS spectroscopy technology. The resulting products exhibited efficient UV light absorption in the range of 225–325 nm, leading to excellent photoinitiating effects as photoinitiators in light‐cured coatings. The cured film showed comparable mechanical performance with the commercial product. Moreover, we discussed the photoinitiation mechanism of the new benzophenone derivatives, which would promote the further development of novel photoinitiators for industry application.

Research on the Flow-Induced Stress Characteristics of Head-Cover Bolts of a Pump-Turbine during Turbine Start-Up

Yang²,

et al. 2022

Energies

Nowadays, pump-turbine units have to experience multiple start-stops every day to balance the power production and consumption on the grid. During the transient process of turbine start-up, the hydraulic forces applied to the head-cover would change dramatically and induce high-level stresses on the head-cover bolts. As key components of large hydraulic turbine units, the head-cover bolts are subjected to tens of thousands of tonnes of hydraulic excitation force during operation. Special attention should be paid to the design of the head-cover bolts of large hydraulic pump-turbine units because these units have high water heads and high hydraulic excitation forces. Therefore, the safe design of the head-cover bolts is extremely important to maintain the operational safety of the whole unit. This paper investigates the flow-induced stress characteristics of the head-cover bolts during turbine start-up in a large prototype pump-turbine unit. A complete 3D fluid model and a corresponding 3D structural model, including the head-cover bolts of the pump-turbine unit, were created. The fluid–structure coupling method was used to calculate the structural stresses caused by fluid flow during turbine start-up. The pressure files during turbine start-up calculated by the CFD tool were transferred and mapped to the finite element model of the structural components of the pump-turbine unit. Subsequently, the flow-induced stress characteristics of the head-cover bolts were numerically simulated. The simulation results showed that the hydraulic excitation force on the head-cover bolts increased significantly during turbine start-up, and the displacement and the stress distributions of different head-cover bolts were not uniform. The calculation methods and conclusions in this paper can also be applied to evaluate the flow-induced stress characteristics of head-cover bolts for similar hydraulic pump-turbine units.