The Nano-copper/LDPE Composites Prepared By Solution Blending Method And Its Properties Investigation

The intrauterine device (IUD) has become the most widely used contraceptive tools inthe world owning to its safe, effective, economic, convenient, reversible, enduring andother peculiarity. And the Cu/LDPE nanocomposites have been chosen as the preparedmaterials of the novel IUD because of the excellent biocompatibility with human body andlow side effect. In the previous study of the Cu/LDPE nanocomposites, the preparation ofthe composites all adopted the mechanic blending and extrusion melting method. With thetraditional method, a fault would be unavoidable: the copper nano-particles couldn’t bedispersed evenly in the LDPE matrix, and the agglomeration would turn up.In order to enhance the dispersibility of the copper nano-particles in the LDPE matrix,the solution blending method is first employed to prepare the Cu/LDPE nanocomposites inthis paper. And the samples prepared by traditional extrusion melting method is also usedfor comparison. This paper mainly focuses on the study of the dimension morphologydispersion of the copper nano-particles in the LDPE matrix, nonisothermal crystallizationbehavior of the composites, the copper ion release of the composites during the long-timeincubation in the SUS, the thermostability of the composites, the changes of thecomposites after one year incubation in the SUS.The results reveal that the copper nano-particles can be dispersed evenly in the LDPEmatrix when the solution blending method is employed, and the agglomeration iseliminated. While when the traditional extrusion melting method was adopted, the coppernano-particles agglomerate in the LDPE matrix and the size can be more than5μm.Through the long-time monitor of the copper ion release, the release rate of theS-nanocomposites is more stable and continuous, which is in proportion to the coppercontent of the composites. And the releasing curves of the composites with differentcopper content would not intersect with each other. The results of the nonisothermal crystallization behavior prove that the crystallization ofLDPE can be prompted when solution blending method is adopted and the crystallizabilitycan be affected by the dispersibilty of the copper nano-particles. When the relativecrystallinity Xt＜0.5, the active energy Eaof the S-nanocomposites is relatively lesser;while when Xt≥0.5the crystallinity is facilitated owning to the agglomeration of thecopper nano-particles in the E-nanocomposites.The thermostability of the composites is investigated by TG, the results indicates thatthe thermal decomposition starting temperatures of the S-nanocomposites are relativelylower, and the difference of the thermal decomposition starting temperatures betweenS-nanocomposites and E-nanocomposites increase with increasing of the copper content.After one year incubation in the SUS, the disperse of the copper nano-particles does notappear decrease progressively from inner to surface.