Preparation and rheological properties of PVC liquid damping materials

Polyvinyl chloride (PVC)-based damping materials were prepared with PVC as matrix, dioctyl terephthalate (DOTP) as plasticizer, super fine active CaCO3 as filler, OP-10 as emulsifier and liquid paraffin as lubricant in the presence of calcium and zinc heat stabilizer (denoted as Ca-Zn). The properties and morphology of the samples were characterized by dynamic rheometer, dynamic thermomechanical analyzer and SEM. The orthogonal design was used to explore the influence of each component on the performances of material. The results showed that the mass ratio of CaCO3 to DOTP had the most significant effect on its damping performance of PVC-based damping materials. When the frequency was in the range of 0.01~150 Hz, the tanδ maximum value of the damping material with m(PVC): m(Ca-Zn): m(CaCO3): m(DOTP): m(OP-10)=42.75: 2.25: 31.8: 21.2: 2 reached 0.604 at 25℃. The apparent viscosity was 3738 and 2.19 Pa•s at a shear rate of 0.1 and 150 s-1, respectively, which showed that the sample had excellent sag resistance and stability. Based on the morphological analysis of the samples, a microagglomeration model was established, and the mechanism of agglomeration-disagglomeration of rigid filler and the deformation of polymer microspheres on the rheological properties was proposed. © 2021, Editorial Office of FINE CHEMICALS. All right reserved.