Polymers with particle inclusions have wide applications,and the mechanical properties of polymer composites affect their reliability in service.The strength of these composites is dependent on factors such as particl...Polymers with particle inclusions have wide applications,and the mechanical properties of polymer composites affect their reliability in service.The strength of these composites is dependent on factors such as particle fraction,size,distribution,and interface interaction between the two phases,in addition to the properties of the polymers and particles.The size effect of particles and interface damage play an important role and thus draw considerable attention.In this paper,the size-and interface-dependent strength of polypropylene(PP)with nano/micro silica(SiO_(2))particles of different fractions is studied through a combination of tensile experiments on a series of samples and corresponding three-dimensional(3D)finite element modeling.The results indicate that PP with 2%SiO_(2)nanoparticles of 50 nm exhibits relatively higher tensile strength,shedding light on the microstructure mechanism where smaller particle sizes lead to better interface bonding.Furthermore,the particle size and interface coupling effect is analyzed based on the size-dependent elastic modulus model and the interface-cohesive model.The simulation demonstrates the local interface damage evolution around a particle of the composites in tension.These findings are beneficial for designing polymer composites with nanoparticle inclusions.展开更多
基金sponsored by the National Natural Science Foundation of China(Grant Nos.12172035,92160203,and 91860102)the fundamental Research Funds for the Central Universities of China(buctrc201930).
文摘Polymers with particle inclusions have wide applications,and the mechanical properties of polymer composites affect their reliability in service.The strength of these composites is dependent on factors such as particle fraction,size,distribution,and interface interaction between the two phases,in addition to the properties of the polymers and particles.The size effect of particles and interface damage play an important role and thus draw considerable attention.In this paper,the size-and interface-dependent strength of polypropylene(PP)with nano/micro silica(SiO_(2))particles of different fractions is studied through a combination of tensile experiments on a series of samples and corresponding three-dimensional(3D)finite element modeling.The results indicate that PP with 2%SiO_(2)nanoparticles of 50 nm exhibits relatively higher tensile strength,shedding light on the microstructure mechanism where smaller particle sizes lead to better interface bonding.Furthermore,the particle size and interface coupling effect is analyzed based on the size-dependent elastic modulus model and the interface-cohesive model.The simulation demonstrates the local interface damage evolution around a particle of the composites in tension.These findings are beneficial for designing polymer composites with nanoparticle inclusions.