Study On Preparation And Properties Of Shape Memory Crosslinked Polycaprolactone And Its Composite

As a new smart material,shape memory polymers are attracting more and more researchers' attention.Compared with the traditional shape memory alloy,shape memory polymer has advantages,such as lighter,lower cost,larger deformation,and easier processing,which has great development space and wide application prospect.Polycaprolactone is a polymer with non-toxic,environmentally friendly and biocompatible.Because of its biodegradability and ease of processing,polycaprolactone had been widely used as biological materials.In this paper,polycaprolactone used as a shape memory polymer had been studied.The property of shape memory was realized by chemical thermocompression crosslinking.The effect of crosslinking initiator on its shape memory property and the thermal and mechanical property were analyzed,and the optimum amount of crosslinking initiator was determinate.And then through the addition of Fe₃O₄ nanoparticles,the magnetic field driven shape memory had been achieved.The specific research contents are as follows:Firstly,according to the shape memory principle of polycaprolactone,the cross-linking polycaprolactone was prepared through initiated by dibenzoyl peroxide and then hot-pressed The amount of initiator was changed to study the change of the shape memory performance and thermomechanical properties of the crosslinked polycaprolactone at 5%,10% and 15% of the initiator mass fraction.Then,through the fatigue strength test,cycle test and other mechanical tests,dynamic thermomechanical test,differential scanning calorimetry,thermogravimetric test and shape memory effect test and other shape memory performance test,a comprehensive study of the synthesis of poly mechanical properties,thermal properties,and shape memory effects of caprolactone shape memory polymers.The effects of different benzoyl peroxide initiators on the shape memory properties were compared and analyzed.Finally,based on the above-mentioned test,the comprehensive performance of the shape of memory polycaprolactone materials with the best benzoyl peroxide initiator content was determined.The shape memory polycaprolactone were prepared by hot-press crosslinking by adding Fe₃O₄ nanoparticles with different mass fraction.The thermal properties,mechanical properties and shape memory properties of polycapro-lactone were tested.And then the magnetic drive shape memory effect of the shape memory polymer is realized under the magnetic induction coil.The results show that the optimum content of benzoyl peroxide is 10%.The shape memory performance of shape memory crosslinked polycaprolactone and its Fe₃O₄ nanoparticles composite is good and the shape recovery rate can reach 99%.At the same time,the composite material can achieve shape memory under magnetic field.The magnetically driven shape memory performance is also outstanding.