High Damping Polyurethane Elastomer With Wide Temperature Range Based On Design Of Network Structure

With the rapid development of science and technology,military and civilian fields toward low energy consumption and automation direction of high speed and light weight development.At the same time,the vibration and noise generated with a high degree of automation in all aspects of life,which does harm increasingly to production and human health,vibration and noise reduction has become a pressing matter of the moment.With excellent performance of polyurethane elastomer material,currently,the polyurethane damping material has the effective temperature range(tan??0.3)of applications on the market about 40?~60?.Most of them show a good damping effect at room temperature.however,below the room temperature,the effect is very poor.The temperature range of polyurethane elastomer limits of which as the application of damping materials.This paper based on the network structure design,through the introduction of long pendent chains and terminal hydroxyl hyperbranched polyester to change the free volume,microphase separation and hydrogen bond interactions.Using Methoxypolyethylene glycol with TDI synthesis of pendent chains prepolymer.With the pendent chains into crosslinking network,atomic force microscopy(AFM)showed that the pendent chains which helpes to improve the compatibility of soft and hard segment,reduced the degree of micro phase separation,the longer of the pendent chains palyed a more significant role in it.Dynamic mechanical analyzer(DMA)analysis showed that the longer pendent chains,the higher the proportion,after the glass transition peak(Tg),the formation of the "damping factor platform" wider,broaden the damping temperature range was more obvious.When the pendent chains ratio reached 67%,the damping temperature range over 150?,when the temperature is 100?,the damping factor is still more than 0.3.The terminal hydroxyl hyperbranched polyester,innovatively,was used as a chains extender in the crosslinking network.Positron annihilation spectroscopy(PALS)data showed that the value of R ratio is smaller,cross-linked network structure free volume fraction is larger.So pendent chains has more responsive space,easier presente to the relaxation.Atomic force microscopy(AFM)phase diagram showed that with the introduction of hydroxyl-terminated hyperbranched polyester,polyurethane elastomer compatibility between soft and hard segments increased.Fourier transform infrared spectroscopy(FT-IR)showed that the infrared spectra of hydroxyl terminated hyperbranched polyester and the pendent chains helps to greatly enhance the hydrogen bonding.Dynamic mechanical analysis(DMA)showed that the collaborative effect to broaden the damping temperature range over 170?,high temperature is up to 120?.Based polyurethane elastomer network structure to design and fabrication of wide temperature range and high damping polyurethane elastomer material,which could meet the high damping values in the temperature range of using(tan??0.3).Damping material is expected to be used in the field of aerospace,transportation,construction and other fields.