Study On The Influence Of The Ultrasound On Polymerization Effect

Up to now,power ultrasound has made a good performance in many aspects such as chemistry,medicine,food industry,industrial welding,wastewater treatment and material improvement,and has become an indispensable part of the manufacturing industry.A large number of data studies show that power ultrasound can also play an important role in the polymerization.Therefore,in combination with the actual needs of underwater acoustic transducer technology,this paper studies the influence of power ultrasound on the polymerization conditions by taking the polymerization of PDA by acrylamide and polyurethane by prepolymer as examples.Firstly,the mechanism of polymerization of acrylamide to PDA and prepolymer to polyurethane was analyzed.Then,according to the influence of power ultrasound on the three different processes of chain initiation,chain growth and chain termination in the two polymerization,two sets of polymerization and prepolymer were established by using ultrasonic transducer and cylindrical container respectively Finally,the effects of ultrasonic frequency and power on the curing time and viscosity of the polymerization of acrylamide to PDA,and the effects of ultrasonic frequency,power and action time on the curing time and sample density of the two stages of prepolymer treatment and polyurethane polymerization in the reaction were studied The influence of degree and complex reflection coefficient.The results show that:(1)in the polymerization of acrylamide to PDA,the viscosity of the sample is the highest when the ultrasonic frequency is 40 k Hz and the power is 80 W,which is 55.9% and 57.5% higher than that without ultrasonic,and the curing time is the shortest,which is 26.4% and 22% shorter respectively.(2)In the polymerization of polyurethane,after the introduction of power ultrasound into the two stages of the synthesis of polyurethane,each index has obvious changes.In the polymerization stage,when the ultrasonic frequency is 20 k Hz,the power is 80 W,the time is 20 min,and the reaction temperature is 70 ?,the density of the sample increases by about 7.52%,the final curing time shortens by about 11.8%,and the modulus of the complex reflection coefficient increases by 15.8%;in the prepolymer treatment At the same time,when the ultrasonic frequency is 40 k Hz,the power is 60 W,and the experimental synthesis temperature is 48 ?,the density of the sample increases about 6.8%,the final curing time shortens about 11.8%,and the mode value of the complex reflection coefficient increases 16.6%.