Preparation And Research Of Polybutyl Methacrylate Composite Damping Material

With the development of machinery and equipment towards high speed,high efficiency and automation,vibration and noise reduction has become an urgent problem to be solved.Viscoelastic polymer as a damping material is one of the effective ways to solve this problem.In order to broaden damping temperature range and improve damping property,it is often necessary to modify it by copolymerization and blending.Polybutyl methacrylate(PBMA)was used as matrix to prepare composites by solution blending with magnetic particles Fe3O4 and ?-Fe2O3(Fe3O4 of demagnetization).The effects of particle content and dispersion on damping properties were investigated.The graphene/Fe3O4(GF)composite particles were obtained by surface modification of Fe3O4.The particles before and after modification were added to PBMA matrix respectively.The effect of interaction strength on the damping properties of the composite was investigated.The effects of second monomers on the damping properties of BMA monomers were studied by emulsion polymerization with second monomers of styrene(St)and methyl methacrylate(MMA)respectively.P(BMA-co-St)and P(BMA-co-MMA)polymers with good damping properties were selected in the copolymers.C9 petroleum resin and hindered phenol AO 1010 were added to modify the copolymers.The effects of filler content,compatibility and hydrogen bond on the damping properties of the materials were investigated.The structure and composition of the particles and polymers were characterized by1H-NMR and FTIR.The micro-morphology of the materials was characterized by scanning electron microscopy(SEM),and the damping properties of the materials were investigated by dynamic mechanical properties(DMA).For PBMA/inorganic particle composites,it was found that the addition of three inorganic particles(Fe3O4,graphene/Fe3O4 and ?-Fe2O3)improved the damping properties of the composites.For Fe3O4 and GF,the tan? peak value of PBMA/Fe3O4 composite is higher than that of PBMA/GF.Specific surface area and pore size tester show that the interaction between GF and PBMA matrix is stronger than that of Fe3O4,which indicates that the strong interaction can suppress the tan? peak height of composites.For Fe3O4 and ?-Fe2O3,the tan?peak value of PBMA/Fe3O4 composites is lower than that of PBMA/?-Fe2O3.SEM shows that dispersion of ?-Fe2O3 in PBMA matrix is better than that of Fe3O4,which can better improve the damping peak of the composite.When the content of ?-Fe2O3 is 1%,the tan?peak value of PBMA/?-Fe2O3 composites is 1.63,and the corresponding effective damping temperature range is about 103 C.Moreover,it is also worth mentioning that Tg of composites shifts to low temperature.After introducing PS and PMMA hard segments into PBMA,the tan? peak of the corresponding copolymers is effectively increased,and the effective damping temperature range of the corresponding copolymers is broadened.For P(BMA-co-1%St)/C9 resin hybrid system,with the increase of C9 resin content,the tan? peak value of P(BMA-co-1%St)/C9 resin composites increases,and the corresponding temperature of tan? peak value shifts to high temperature gradually.When the mass fraction of C9 resin is 50%,the tan? peak of P(BMA-co-1%St)/C9 resin composite is 2.33,and the corresponding damping temperature range is 71.74?.In addition,it was found that the compatibility of C9 resin and P(BMA-co-St)copolymer could be improved when the amount of second monomer St was increased,so that the damping properties of the composites could be better improved.For the P(BMA-co-2%MMA)/AO1010 hybrid system,with the gradual increase of hindered phenol AO1010 content,the tan ? peak of P(BMA-co-2%MMA)/AO1010 composite also increases continuously,and the temperature corresponding to the tan? peak also shifts to the high temperature direction.This is because hindered phenol AO 1010 forms a large number of hydrogen bonds with the matrix.These hydrogen bonds are destroyed and formed in the condition of variable force,which consume energy,thus enhancing damping properties of the material.When the content of hindered phenol is 50%,the tan? peak value of P(BMA-co-2%MMA)/AO 1010 composite reaches 2.33,and the corresponding damping temperature range is 69.41?.However,by increasing the amount of the second monomer MMA,increasing the glass transition temperature of the copolymer,it was found that when the glass transition temperature of the composite approached 90?,the hydrogen bond formed between the hindered phenol AO1010 and P(BMA-co-MMA)polymer was destroyed,resulting in the decrease of the damping property of the material.