Optically active helical polyurea@attapulgite composites with high dielectric constant and low infrared emissivity

Optically active helical polyurea@attapulgite (HPUA@ATP) composites were prepared after the surface modification of the rod-like attapulgite (ATP). Composites were characterized by Fourier-transform infrared spectroscopy, X-ray diffraction and thermogravimetric analysis. The results indicate that the helical polyureas have been successfully grafted onto the surfaces of the modified ATP (A-ATP) without destroying the original crystalline structure of ATP. The rod-like nanoparticles were confirmed by transmission electron microscopy. The dielectric constant and infrared emissivity have been investigated, and the results indicate that the dielectric constant value of HPUA@ATP composite has been increased to 33.62 from 25.35 (the value of bare ATP), while the infrared emissivity value of HPUA@ATP composite has been reduced to 0.39 from 0.93 (the value of bare ATP), due to the interfacial interactions between organics and inorganics and the ordered stereostructures of optically active helical polymers.