Polyurethane/organic vermiculite composites with enhanced mechanical properties

摘要

In this article, a series of polyurethane (PU)/organic vermiculite (OVMT) composites are prepared by intercalating polymerization. 1,4-cyclohexane diisocyanate (CHDI) as hard segment of PU is designed to improve the decomposition temperature of composites. Vermiculite (VMT) is modified by method of cation exchange with octadecyl trimethyl ammonium bromide (OTAB); the resulting product OVMT with the function of physical cross-linking disperses well in soft segment of PU polycarbonate polyol (PCDL), which improves the mechanical properties of composites obviously. This modification further enlarged the interlayer of OVMT and improved the properties of composites. The structure and properties of OVMT and PU/OVMT composites are characterized by Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, scanning electron microscope, and tensile strength test. The results showed that the layer spacing of OVMT increased 1.41 nm compared with that of VMT (the value of layer spacing of VMT is 0.96 nm) and further enlarged to 2.92 nm by the loading of PCDL. The tensile strength and the strain at break of PUCPB/OVMT (3.0%) composites reached 26.8 MPa and 443%, respectively. The temperature resistance of PUCPB/OVMT (3.0%) composites is above 300 degrees C, which is more suitable for the steam channeling plugging of heavy oil. (c) 2015 Wiley Periodicals, Inc.