Molecular dynamics simulation of mechanical properties and surface interaction for HA/PLA

HA/PLA composite material can realize the complementary advantages in the very great degree, was expected to become an ideal bone replacement material. In this paper, molecular dynamics simulation was applied to investigate the binding energy of PLA on HA crystallographic planes (001), (100) and (110), and then the mechanical properties and radial distribution function of the HA(110)/PLA mixed system were calculated and analyzed. The results show that HA (110) has the highest binding energy with these polymers because of its higher planar atom density than that of HA (001) and (100). By calculating the radial distribution function, the interface interaction and its essence of the HA(110)/PLA were elucidated. There was a strong interaction between HA crystallographic plane (110) and PLA, it was mainly derived from the hydrogen bonds between O atoms of PLA and H atoms in HA crystal. The PLA component plays a significant role in strengthening the mechanical properties of HA. And the mechanical properties of HA/PLA in each direction was closer than single component HA, thus overcoming the defects caused due to the anisotropy of the material.