Preparation And Application Of Hydrogenated Nitrobutyronitrile Rubber

In this paper,the hydroxy-terminated nitrobutyronitrile liquid rubber(NHTBN)and nitrobutyronitrile rubber(NNBR)were successfully prepared by one-step method.This method greatly simplifies the epoxidation two-step method of the traditional nitrification method of rubber macromolecules.After further hydrogenation of the obtained nitrified nitrile rubber by using transition metal catalyst,hydrogenated nitrobutyronitrile rubber was obtained.The strong reactivity of nitro acid provided a new chemical modification of hydrogenated nitrile rubber.Research ideas.In addition,the selective catalytic hydrogenation of the nitrobutyronitrile rubber by FeO(OH)catalyst is achieved,and the Tg of the partially hydrogenated nitrobutyronitrile is lowered.The details are as follows:(1)The nitration of HTBN and NBR by Fe(NO3)3·9H2O--TEMPO nitration system,NaNO2--CAN nitration system,AgNO2--TEMPO nitration system and NaNO2--I2 nitration system,respectively,through FTIR,1H-NMR and elemental analysis,etc.The test method successfully prepared NHTBN and NNBR,and the NaNO2--I2 nitration system obtained the best nitrification activity of nitrile rubber,and no gel was produced during the reaction of the system.Under the optimum process conditions,NHTBN has a degree of nitrification of 20%and NNBR has a degree of nitrification of 9%.(2)Catalytic hydrogenation of NHTBN with transition metal catalyst to obtain HNHTBN and HNNBR with a degree of hydrogenation of more than 90%.The use of nitro is a new research idea for the chemical modification of hydrogenated nitrile rubber.The influence of the presence of nitro group on the hydrogenation reaction conditions of hydrogenated nitrile rubber was analyzed.It was found that the main influence was that the polarity of the solvent was higher.(3)The selective hydrogenation of NHTBN by FeO(OH)catalyst gave a selectively hydrogenated product,partially hydrogenated NHTBN,which was reduced to a carbon-carbon single bond by a nitro-bonded carbon-carbon double bond.The method has successfully reduced the glass transition temperature of NHTBN and enhanced its cold resistance.