Research Of Nano-material Modified Thermoplastic Polyurethane Composites

Thermoplastic polyurethane（TPU）,a new type of green raw material with high performance,has been widely used in national economic fields,such as national defense,medical care,sports,oil fields and mines.It has excellent performance including high strength,good toughness,wear-resistant,anti-ultraviolet,et al.However,TPU still has some defects in performance.Furthermore,with the advance of science and technology,the using of TPU has became more and more seriously.By adding nano-materials can improve TPU performance defects,obtain better performance and expand the scope of using TPU.In this paper,prepared several kind of nano-materials,and using solution blending prepared TPU nano-composites.The structure and properties of nanoparticles and TPU nano-composites were systematically studied by means of FT-IR,AFM,TEM,TGA,SEM and other testing methods.The main research of this study is as follows:1.Using the di-amine（–NH₂）functionalities on the sides of the ethylenediamine（EDA）react with epoxy group of GO by a nucleophilic ring opening reaction,synthesized the stiching graphene oxide（GOE）.Via the hydrolysis-condensation reaction of TEOS on the surface of GO and GOE fabricates silica nanoparticles-covered graphene oxide（GOS）and silica nanoparticles-covered stitching graphene oxide（GOES）nanoparticles,respectively.Then,prepare the GO/TPU,GOE/TPU,GOS/TPU and GOES/TPU nano-composites by solution blending.The effect of different loading of GOES nanoparticles and different nanoparticles with same addition on the thermal stability and mechanical properties of TPU nano-composites were investigated,respectively.When the amount of GOES nanoparticles is 2 wt%,the results show that the tensile strength and elongation at break of TPU nano-composites reach the maximum,it reached 48.9 Mpa、2140%,respectively.2.Through hydrolysis condensation reaction of TEOS,KH560 on the surface of GO,fabricates SiO₂ nanoparticles coated graphene oxide（GOK）,the epoxy groups are successful introduced,which provides reactive sites for the amino groups of ethylenediamine（EDA）and different molecular weight polyethyleneimine（PEI）（Mw=1800,10000）.The GOKE,GOKP-1800 and GOKP-10000 three kinds of nanoparticles are prepared by ring opening reaction of amino and epoxy groups.Then,GOKE/TPU,GOKP-1800/TPU and GOKP-10000/TPU nano-composites are prepared by solution mixing method.The thermal stability and mechanical properties of TPU nano composites with different amounts of GOKP-10000 nanoparticles and the same amount of different nanoparticles were studied,respectively.The results show that the tensile strength of TPU nano-composites reach the maximum when the amount of GOKP-10000 nanoparticles is 0.5 wt%,it reached 44.4 Mpa.3.The TPU is modified by solution blending method with different nanoparticles,including SiO₂ nanoparticles are modified by KH550（K5S）,SiO₂ nanoparticles are modified by KH570（K7S）,SiO₂ coated sitching graphene（GOES）and PEI molecular weight of 10000 modified graphene oxide（GOKP-10000）.The mechanical properties,hydrolysis resistance and heat aging properties of TPU nano-composites were studied.The results show that the tensile strength and elongation at break of GOES/TPU nanocomposites reached the maximum when the amount of GOES nanocomposites was 2 wt%.The addition of a certain amount of nanoparticles could improve the water resistance and aging resistance of TPU composites,and TPU composites showed good heat aging properties.Further,the composites of aramid fiber and modified TPU were prepared by hot pressing method.The tear strength of the composites and the peel strength between aramid fibers and TPU are studied,respectively.When the amount of GOES was 2 wt%the tear strength of aramid fibers and TPU composites reached the maximum value of 49.0 KN/m.