UV Curing Humidity Resistance Composite

Polymer nanocomposite is a kind composite material that a variety of nanoscale particles were dispersed in the polymer matrix which combination the superior characteristics of organic polymer materials and the inorganic particles. The mechanical properties and thermal stability of the polymer nanocomposite materials were improved significantly, and with some special properties of polymer materials, such as high barrier, high conductivity, high flame resistance, excellent optical properties. It is an economic effectiveness method to prepare the new high-performance materials.In this thesis, preparation of the organic/inorganic hybrid humidity resistance materials by UV photopolymerization combines the advantages of both nanocomposites and the UV photopolymerization. A photopolymerisable quaternary ammonium salt (PQAS-18) was synthesized and intercalated into the inorganic montmorillonite (Na-MMT) as organic modifier to preparation a novel organic-inorganic hybrid nanoclay by cationic exchange process. Then the hybrid nanoclay was added into the photopolymer matrix and after UV exposure, the lamellar structure of MMT was exfoliated to form a peeling state and dispersed in the polymer matrix because the active groups between the layers participate the polymerization. The composite material has good moisture resistance properties, because the exfoliated MMT layers which dispersed in the polymer matrix provide a barrier to the gas molecules or water vapor.XRD results showed that the layer spacing of the modified MMT was increased from the original 1.515 nm to 4.152 nm when the synthetic long chain photopolymerisable quaternary ammonium salt was intercalated into the layers. Fourier transform infrared spectroscopy (FTIR) confirmed that the PQAS-18 with active groups intercalated into the layers of the MMT still retain a high reactivity, and can participate in the UV polymerization. Thermo gravimetric analysis (TGA) showed that the amount of PQAS-18 intercalation was about 60%. The test of the water vapor transmission (WVT) of the cured film showed that the WVT of hybrid film was much lower than that of the pure polymer film. Experiments showed that when the hybrid soil was added by 3%, the WVT of the cured film was the lowest and the moisture resistance was the best.