| Vibration and noise can be seen everywhere in our lives.It will not only affect people's physical health but also endanger the life of equipment,buildings,etc.In order to eliminate the damage caused by vibration and noise,people usually use damping materials to absorb noise and vibration.In order to reduce the dependence of traditional damping materials on ambient temperature and frequency of use,researchers developed piezoelectric damping materials.With the advancement of science and technology,people have put forward higher requirements for piezoelectric damping materials,and piezoelectric damping materials that can be used in harsher conditions such as high temperature and high humidity have attracted more and more attention.In this paper,phenolic hydroxyl terminated polyaryletherketone oligomers with different molecular weights were prepared,and these oligomers were polymerized with dimethylaminoterminatedpolyorganosiloxaneoligomerstoobtain polyaryletherketone-polysiloxanes.A series of multi-walled carbon nanotubes/barium titanate/poly(aryl ether ketone)-polysiloxane block copolymer based piezoelectric damping materials were prepared by alkane block copolymers(PAEK-b-PDMS)..Observe the changes in the microstructure of different composite materials,study the effect of changes in the loading of multi-walled carbon nanotubes and barium titanate on the damping properties of the composite materials,and try to develop a type of material that can be used under harsher conditions such as high temperature and high humidity.Piezoelectric damping material.The main research content includes:In the first part,polyalkylene ether ketones with different molecular weights were prepared by copolymerizing 4,4?-(hexafluoroisopropylidene)diphenol and 4,4?-difluorobenzophenone with different excess ratios.Polymer.It was then polymerized with a dimethylamino terminated polyorganosiloxane to give a series of polyaryletherketone-polysiloxane block copolymers(PAEK-b-PDMS).PAEK-b-PDMS has a microphase separation structure due to the introduction of polyorganosiloxane.With the increase of the content of polyorganosiloxane,the contact angle of the block copolymer gradually increased.The contact angle of the block copolymer 1100F-PAEK-PDMS was 112°C,which showed better hydrophobicity;vitrification The transition temperature(T_g)gradually decreases and the elongation at break increases.Block copolymers have good thermal stability with a 5%thermal decomposition temperature of 394 ~oC.In the second part,block copolymer 1100 F-PAEK-PDMS was selected as the matrix,barium titanate(BT)was used as the piezoelectric phase,and multi-walled carbon nanotubes(CNTs)were used as the conductive phase.CNTs/BT/1100 F-PAEK-PDMS piezoelectric damping composites.Through the study of the micro-morphology of the composite material,it is found that the filler material is distributed evenly in the matrix and has a good interfacial adhesion with the resin matrix.The EDX study showed that the filler material was selectively dispersed in the polyaryletherketone phase.The damping performance study results show that when the content of CNTs increases,the electrical conductivity of the composite gradually increases to the semiconductor,and when the content of BT is appropriate,the damping performance of the composite is the best.Among them,the composite material 0.5 wt%CNTs/50 wt%BT/1100 F-PAEK-PDMS has the best damping performance,and its effective damping temperature range is 60 ~oC(55~115 ~oC).At the same time,we also examined the damping properties of composites treated with organic solvents,boiling water,and acid-base solutions.We found that the damping properties of the treated composites did not change much with those of untreated materials,indicating that our composites can Used in high temperature and high humidity conditions,it is a kind of piezoelectric damping material with potential application under harsh environment. |
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