SPECTROSCOPIC, THERMAL, AND MECHANICAL CHARACTERIZATION OF CARBOXYL-TERMINATED POLYBUTADIENE-BASED CARBON BLACK-FILLED NETWORKS

Carbon black-filled and unfilled carboxyl-terminated polybutadiene (CT PB) networks were prepared by using two types of reactive systems at d ifferent reactive group ratios to be applied to the solid propellant m otor case as a liner. For the preparation of CTPB networks, tris(2-met hyl-1 aziridinyl)phosphine oxide (MAPO) and a mixture of liquid bisphe nol A-epichlorohydrin (Epikote-828) and MAPO were used as two differen t reactive systems. The chemistry and thermal stability of the CTPB ne tworks were followed by Fourier transform infrared spectroscopy (FTIR) and thermogravimetry (TG) techniques, whereas mechanical and adhesive properties were tested by tensile measurements. The mixed reactive sy stem caused a modification in the ultimate tensile stress and elongati on-at-break properties, adhesive properties, and thermal stability of the CTPB networks. It was understood that this modification was due to the inter-and intramolecular bridge formation via the end-linking rea ction of Epikote-828 with amine groups of the former network chains. T he combination of MAPO with Epikote-828 also imparted better peel and lap-shear strength properties to the CTPB elastomers. (C) 1997 John Wi ley & Sons, Inc.