| Nowadays harmonious integration with the environment and the desire to save energy is a very important research topic. For the sake of energy saving, great efforts are being done on the possibilities of reducing the use of air conditioning systems in automobile and building. Meanwhile, people also seek to diminish the time using artificial lighting. Therefore, glasses with a low solar factor and high light transmittance in the wavelength range from 380nm to 780nm are highly desired in many applications such as automotives and architectures. Philippe S predicted a trend in coating technology for surface modification of automotive glass and architectural glass, i.e., high-performance glazing will include the following five characteristics: solar factor tending towards 0, light transmittance approaching 1, color rendering index closing to 1, non-reflecting glass, and thermal high-performance insulation. Conventional solutions to overheating are the usage of sunscreen thermal insulation film and film-coating glass. These solutions are paradoxical in that a reduction achieved in solar heat gains goes in tandem with a reduction in light transmission. Moreover, it is in conflict with the desire for reflectivity. Film-coating glasses are widely used as transparent and heat-insulating materials at present. Based on reflection principles of light, it is feasible to plate a layer of metal ions on glass substrate for reducing the disadvantage of overheating due to solar gains and transmitting the exterior light with altering its color. However, metal ions are easily oxidized. The oxidation inevitably not only destroys the effects of insulating heat and transparency but also interferes the aeronautical telecommunication. It is urgent to develop a novel transparent heat-insulating coating, with the trend of non-reflecting transparent clear glass and the desire to reduce near-infrared ray transmission. It will partially compensate the expensive price due to the complicated manufacturing process of sunscreen thermal insulation film and film-coating glass. In this paper, anti-infrared/ultraviolet metal oxides were selected by pulsed laser deposition (PLD) at first. Afterwards, a series of blended polymer composite film, sol-gel composite film and organic/inorganic composite film were prepared by in-situ free radical polymerization, polymer membrane template and emulsion-free polymerization, respectively. Their anti-infrared/ultraviolet properties were characterized in detail by UV-VIS and FTIR in the wavelength range of 190 -2500 nm. The results could be a guide for developing an anti-infrared/ultraviolet coating to implement heat insulation in many applications. A series of monolayer and multilayer films individually composed of zinc, iron, titanium, silver, aluminum, silicon and copper oxides were deposited on quartz substrates by PLD technique using metal targets in oxygen atmosphere. in order to study the anti-infrared and ultraviolet radiation capacity of metal oxides in the deposited thin film. According to UV-VIS and IR spectra, for monolayer films, zinc oxide can absorb above 90% in ultraviolet range (190 to 400nm) Silver oxide film possesses the best property of anti-near-infrared which transmittance in near-infrared region (780.to.2500nm) can reach about 40%. The light transmittance approaches 1 for zinc oxide film. The PLD is an expeditious means that can supervise developing an anti-infrared/ultraviolet coating. Several kinds of sol-gel composite films —inorganic oxides(including Fe2O3,TiO2 ,ZnO)/polyacrylate acid had been synthesized by sol-gel method and means of free radical polymerization. UV-VIS and FTIR experimental results demonstrated anti-infrared/ultraviolet property of these films could be resulted from the combination of the absorbency,reflection or transmission effect between the nano particles inside the films. Fe2O3 /PAA had the best anti-ultraviolet property among these compounds which almost obstructed all ultraviolet. TiO2/PAA showed strong ability to insulate near-infrared radiation. When the concentration of TiO2 was 8% transmittance of film of TiO2/PAA in near-infrared region declined to 11%. In addition, the ability of insulating near-infrared radiation increases with the increase of average dimension of TiO2 particle in this compound. TiO2/PAA film demonstrated better anti-infrared/ultraviolet property as well as good diaphaneity when average sizes of TiO2/PAA particle were 2000nm-2500nm. For ameliorating aggregation of nano particles in organic/inorganic composite film, a novel Y2O3-containing sol-gel composite film was synthesized on chelating polymer template-Poly (BA-co-GMA-IDA). UV-VIS and FTIR experimental results demonstrated the polymer template method was better than the routine preparation. In ultraviolet region, the transmittance remarkably lowered from 350 nm and reached to 0 when the frequency was less than 300 nm. Meanwhile, in near infrared wave range the transmittance was 30 %. A kind of anti-infrared/ultraviolet coating was prepared by blending Y2O3-containingsol-gel composite with polyurethane latex. The heat insulation property of coatings on the cloth surface was studied. The temperature descended 10 ℃for black cloth. It can be concluded that the cool cloth had an obviously heat insulation effect. Because of C60's unique structure, we anticipated that it had the intense absorption in near infrared range. High-optical-quality polyacrylate films containing a few load of C60 were prepared by blending the soluble polyacrylate with the fullerene C60 derivative poly-[2-(acrylamido)-2-methylpropane sulfonic acid](PAMPS)-C60. Another C60-containing organic/inorganic composite film was synthesized successfully by soap-free emulsion polymerization with C60,Acrylic,Butyl acrylat. From the TEM morphology, each method can distribute C60 particles evenly throughout organic medium, which may be the result of cooperation of physical absorption and chemical copolymerization. The former is better in dispersing and anti-infrared effect, but the latter has better cure performance that can be not only heat cured but also UV cured. For C60-containing blended polyacrylate films, in visible spectrum, its transmittance was greater than 80%. In ultraviolet region, the transmittance lowered to 10% (< 300 nm). Meanwhile, the transmittance was 55.7% in near infrared wave range (4000cm-1～14000 cm-1) Anti-infrared/ultraviolet property of fullerene-containing polyacrylate film could be resulted from the combination of the conjunct action of nano-scale effect,surface (interface) effect,quantum tunnel effect between the nano particles inside the blended film. Meanwhile, C60's three-dimensional nonlocalized π-conjugated structure exhibited good absorption in ultraviolet and infrared spectra region. The experimental results indicated that anti-infrared/ultraviolet property of C60-containing composite film was improved greatly. Its low transmittance in IR and UV makes the C60-containing blended film and organic/inorganic composite film promising highly potential to serve as an anti-infrared/ultraviolet coating to implement heat insulation In conclusion, the study on transparency anti-infrared/ultraviolet thin coating is in the ascendant. Our works will provide new ideologies and methods for insulating heat functional coating. |
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