Gas and Water Barriers of UV Curable Resin/k-Alumina Organic-Inorganic Nanocomposite Hybrid Coatings

Autor: Jane-Hau Chang, 張展豪
Rok vydání: 2008
Druh dokumentu: 學位論文 ; thesis
Popis: 96
This thesis is divided into two main parts. Part 1 is about surface modification of tabular alumina nanoparticles (kappa-alumina) in an organic solvent. Part 2 is about the gas- and water- permeability of a composite coating consisting of the kappa-alumina particles dispersed in a UV resin. In part 1, polymerisable organic silane molecules [3-(Trimethoxysilyl) propyl methacrylate, MPS] were grafted onto the surface of tabular alumina via hydrolysis and condensation; to which, the hydroxyl groups on the alumina surface were substituted by monomer MPS so that the alumina changes from hydrophilic to hydrophobic (or lyophilic). The surface-modified alumina nanoparticles were examined by XPS, TG/DTA, TEM, FT-IR, contact angle, and Zeta-DLS analyses. XPS results revealed that the MPS molecules adsorb preferentially on the tabular alumina surface, where Si 2p, and Si 2s (both from the MPS molecules) at binding energies of 101.813eV and 153.543eV, respectively, were observed. From IR analyses, the intensity from the functional groups of MPS (e.g., -CH2、-CH3、C=O、C=C and C-H) on the tabular alumina surface increased with the MPS concentration. TEM examinations further reveal that the modified tabular alumina particles were well dispersed in 1,6-Hexanediol diacrylate (HDDA) solvent when the ratio of MPS/ tabular alumina was held at 0.3. In part 2, PET films were tape-casted by a suspension mixture consisting of the modified tabular alumina, organic monomer HDDA, photoinitiator, and prepolymers (oligomer), followed then by UV curing. The films were then characterized by their gas- and water- permeability. An oxygen permeation of 19.4 cc/m2-day and a water permeation of 2.8 gm/m2-day were observed when solid concentration of the alumina-UV resin composite film was 7wt%. UV-Visible result showed that the transmittance of PET/UV resin-alumina nanocomposite was about 90% at wavelengths higher than 500nm (green light). An increase of the solid content in the UV resin film would decrease the transmittance in UV-A region (l = 320 ~ 400 nm).
Databáze: Networked Digital Library of Theses & Dissertations
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