胶原接枝改性用于制备红外低发射率涂层的研究

用甲基丙烯酸甲酯在硝酸铈铵和偶氮二异丁腈的联合引发下对胶原进行接枝共聚改性,并用制得的胶原接枝共聚物颗粒与氧化铟纳米粒子复合制成涂层.研究了接枝反应温度及萃取剂对胶原接枝共聚物及其复合物涂层的红外发射率的影响,同时对复合物涂层红外发射率的降低机理进行了初步探讨.结果表明,在反应温度为50～55℃时,先后用丙酮和水作为萃取剂,可制得粒径为40～80nm的胶原接枝共聚物颗粒,该颗粒与氧化铟纳米粒子复合后,涂层的红外发射率(8～14μm)较单一的胶原接枝共聚物和氧化铟纳米粒子的红外发射率明显降低,胶原接枝共聚物纳米颗粒和氧化铟纳米粒子之间显示出较强的复合协同效应.

Studies on Grafting Modification of Collagen and Application to Preparation of Low IR Emissivity Coating

More and more requirements are put forward to infrared stealth coating with the development of detection technology, therefore, the key point in the infrared stealth coating research is how to achieve the lowest infrared emissivity under the circumstance of being compatible of visible light and radar stealth. Indium oxide powder, which is commonly used for the sake of visible light stealth as a coloring pigment in the preparation of coating, has a high emissivity and cannot lower the emissivity of coating consequently. Collagen, a biomacromolecule material, is a triple helix composed of three polypeptide chains. Owing to a great number of dipoles and molecule-bound charges in collagen molecules, actually collagen is a bioelectret and has the properties of polarization, electrostatics and so on. Additionally, collagen molecule abounds in elements such as oxygen and nitrogen, which shows a good affinity to metal oxide, so collagen can be used to modify and stabilize metal oxide powder. But the native collagen adsorbs water easily so that it cant be directly put into application. In this paper, grafting copolymerization of collagen with methyl methacrylate(MMA) initiated by ammonium cerium nitrate(CAN) and 2,2-azo-bis-iso-butyronitrile(AIBN) was carried out in an aqueous medium. The coating was prepared by the composites of collagen-g-MMA copolymer and indium oxide nanoparticles. The effect of the grafting temperature and the extractive solvent on the copolymer and the IR emissivity of the coating of the composites thereof was studied, and at the same time, the mechanism for the decrease in the IR emissivity of the coating was discussed by contrasting the microstructures of the collagen/indium oxide and copolymer/indium oxide composites. The results showed that the collagen-g-MMA copolymer with a grain size of 40—80 nm could be prepared at 50—55 ℃ with acetone and distilled water as the extractive solvents. The coating prepared by t