Study On Preparation And Properties Of Thermoplastic Polyurethane/MXene Composite

Thermoplastic Polyurethane Elastomer(TPU)is a multi-block copolymer composed of soft and hard segments.It has a unique microphase separation structure and combines the characteristics of plastic and rubber.With excellent physical and chemical properties,TPU has been widely used in many fields.However,its shortcoming is that the performance of pure TPU is single,which limits its application in a wider field.In order to further broaden the application range of TPU,this paper aims at the research hotspot of MXene materials in recent years.The structure design of TPU/MXene composite material is carried out through different processing methods,and the influence of MXene material on the performance of the composite material is studied.The specific research content is as follows(1)Aiming at the problem of poor interface bonding between TPU and MXene,polyethylene glycol(PEG)was used to pretreat MXene nanosheets,and melt blended with TPU to prepare TPU/MXene homogeneous composites.The results show that MXene pretreated with PEG can be uniformly dispersed in the TPU matrix.The addition of MXene effectively increases the crystallization speed of TPU.Under 0.5wt% of MXene,the tensile strength and elongation at break of the composite increase respectively.41.2% and 15.4%.(2)The flexible multilayer TPU/MXene film was prepared by a simple layer-bylayer spraying method.The results show that the multilayer film with a MXene content of 28.6 wt% and a thickness of 52 ?m has high electrical conductivity(1600 S/m),excellent electromagnetic shielding capability(50.7 d B)and high in-plane thermal conductivity(6.31 W/(m·k)).In addition,the obtained multilayer film exhibits excellent Joule heating performance(113 ?),fast response time(< 10 s)and excellent heating stability at low voltage(5 V).(3)The TPU/MXene composite foam was prepared by the combination of directional freezing and dipping method.To solve the problem of poor interface bonding between TPU and MXene,polydopamine was used to modify the TPU foam,and MXene was successfully adhered to the TPU skeleton through multiple dip coatings.The results show that the conductive foam(0.25 S/m)with an MXene content of 3.45 wt% exhibits good resistance response behavior.The composite foam has excellent recognition ability for different compressive strain amplitudes(0%-80%),and good detection ability in a wide stress range(10 Pa-100 KPa).