Application of carbon dioxide capture technology in the process of polyethylene foaming materials

Abstract

Lightweight and multifunctional polymer foams reveal a promising prospect, in terms of reducing energy consumption, and saving materials and resources. Herein, carbon dioxide (CO₂) was captured through three amines, such as ethylenediamine (EDA), 1,3-propylenediamine (PDA) and 1,2-cyclohexanediamine (TRK). CO₂ then released under heat, used as a foaming agent in the preparation of polyethylene (PE) foams. Cyclodextrin nanosponge (NS) was used as a heterogeneous nucleating agent and a carrier for complex of captured CO₂. Evaluation system was developed to control the conditions of combine process, such as thermal and crystallization properties. Results showed that TRK was the proper CO₂ capture candidate, with mass ratio of 1:4 for NS and TRK (NS:TRK-CO₂(1:4)), and the release temperature of CO₂ was 137 ℃. Foamed PE composite was prepared by molding process with NS:TRK-CO₂(1:4). The optimum cell morphology was obtained with 5 wt% NS:TRK-CO₂(1:4), the cell diameter was 116 µm, and the cell density was 7.9×10⁴ cell/cm³. The best fabricated microcellular PE/NS:TRK-CO₂(1:4) composite presented excellent mechanical, thermal and sound insulating performance. The maximum tensile strength of the PE composite was 25.48 MPa, and the maximum bending strength was 11.27 MPa. The impact strength was 5.77 KJ•m^-2, more than 1.5 times higher than pure PE. The thermal conductivity was as low as 0.076 W/m•k, the sound absorption coefficient was 0.737 at 1500 Hz, and the noise reduction coefficient was 0.459.