DOPO characteristics of the hottest o-cresol epoxy

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O-cresol epoxy, introducing DOPO characteristics

recently, the school of chemical engineering, Nanjing University of technology, studied the reaction characteristics of reactive phosphorus containing flame retardant (DOPO) with o-cresol epoxy resin through epoxy value titration and infrared spectroscopy, and finally determined its best reaction conditions. The experimental results show that the best effect can be obtained by adding 20% triphenylphosphine catalyst at 120 ℃ for 120 minutes. The infrared spectrum further confirmed the reaction degree of DOPO with o-cresol epoxy resin and the preliminary structure of DOPO phosphorus containing epoxy resin. DTA analysis method was used to study the reaction kinetics of DOPO with o-cresol epoxy resin. The reaction kinetics parameters ln A0, apparent activation energy E, 298.51 kj/mol and reaction order n were measured. According to experts, epoxy resin, as a thermosetting polymer material, has excellent chemical and physical properties, such as chemical corrosion resistance, adhesion, electrical insulation, high strength and other mechanical properties, but its flame retardancy is not good. Now bromine flame retardants are widely used to retard it. Compared with halogen flame retardants, DOPO is a new reactive phosphorus flame retardant with rapid development. The phosphorus containing epoxy resin synthesized by dopol and its derivatives is halogen-free, smoke-free, non-toxic, non migrating, and has long-lasting flame retardancy. It has been widely used abroad for flame retardancy of plastics, circuit boards and other materials for electronic equipment. By introducing P element into epoxy resin through DOPO, the glass transition temperature of phosphorus containing epoxy resin can reach about 150 ℃, which greatly broadens the application range of materials

at the same time, compared with chain phosphorus containing group epoxy resin, ring phosphorus containing group epoxy resin has better flame retardancy. At present, DOPO as a new phosphorus containing flame retardant has attracted much attention. In this study, the reaction characteristics of DOPO with o-cresol epoxy resin were studied by epoxy value titration and infrared spectrum detection; The reaction kinetics of DOPO with o-cresol epoxy resin was studied by DTA analysis. According to the introduction, the reagents used in the experiment include - adjacent "over packaged" overqualified express waste overload cresol epoxy resin (cjf-43): epoxy value 0.48 "GB 6096 (2) 009-t safety belt test method" stipulates the static load test method of main belt and safety rope mol/100g, Zhonghao Chenguang Chemical Research Institute; DOPO: Shandong Mingshan Fine Chemical Co., Ltd., purity 98%; Triphenylphosphine: chemically pure, Shanghai Lingfeng Chemical Reagent Co., Ltd. The researchers first carried out epoxy value titration and infrared spectroscopy to study the reaction characteristics of DOPO and o-cresol epoxy resin: in a 100ml four port flask, add 16g of o-cresol epoxy resin, heat it to 90 ℃ under nitrogen protection and stir it, then add 2G of DOPO and the corresponding amount of activator triphenylphosphine, gradually raise the temperature to 120 ℃ or 160 ℃, and keep it for 5h. During this period, samples were taken at 30min, 60min, 90min, 120min, 150 min, 180min, 240Min and 300min respectively, and the epoxy value was determined by hydrochloric acid acetone method. Bruker vector 55 Fourier transform infrared spectrometer was used to characterize the structure of the product. About DTA research: reaction kinetics of DOPO and o-cresol epoxy resin, DTA analysis of DOPO and o-cresol epoxy resin was carried out by Shimadzu dta-50 differential thermal analyzer in Japan. Nitrogen atmosphere, heating rate was 20 ℃/min, and the initial reaction temperature, peak temperature and reaction heat were measured

subsequently, researchers conducted an in-depth study on the reaction principle between DOPO and o-cresol epoxy resin, and supported Jixi transformation. It showed that the tension of its ternary ring of epoxy gene was very large, so it was highly active and easy to open the ring. The carbon atoms in the ring were attacked by nucleophiles to form stable compounds. The epoxy value titration and infrared spectrum were also used to study DOPO, and the reaction characteristics with o-cresol epoxy resin were analyzed, including the influence of catalyst on the reaction, the influence of temperature on the reaction, the infrared spectrum characterization of DOPO, and the reaction kinetics with o-cresol epoxy resin. The change trend of epoxy value under different reaction temperatures was similar: the epoxy value gradually decreased with the reaction until it became stable, and the more catalysts, the faster the reaction, The shorter the time to reach the theoretical value, and at the same time, investigate the reaction kinetics of DOPO and o-cresol epoxy resin. According to experts, there are two methods to study the reaction kinetic equation, isothermal method and non isothermal method. DTA research belongs to non isothermal method. Through the treatment of the kinetic equation, the frequency factor A0, the apparent activation energy E, and the reaction order n can be obtained. These parameters are of great significance for understanding the chemical mechanism. Whether the reaction can be carried out is determined by the apparent activation energy of the reaction. The size of the apparent activation energy intuitively improves the recycling rate of plastic packaging materials, reflecting the difficulty of the chemical reaction. The chemical reaction can be carried out only when the molecules participating in the reaction obtain energy greater than the activation energy. Through the determination of curing reaction order, the mechanism of chemical reaction can be roughly estimated. The reaction rate constant can be determined by A0

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