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PCC填料能够被用于提高纸张折射率,折射率的提高会进一步改善纸张的光学性能。该文研究了高折射率的新型PCC填料用于造纸的潜能。在加入折射率增强助剂的条件下,利用传统的碳酸盐法制备PCC试样。研究了用温和的Zn处理PCC试样应用于造纸的潜能;除了Zn处理方法之外,还研究了Sr作为助剂的效能,发现Sr会改变主体粒子的形态和晶体结构。阐述了这种改性对纸张光散射系数、白度、不透明度、抗张强度、松厚度以及孔隙率的影响,分别研究了压光前后纸张的这些性能。研究表明,改性填料有利于改善纸张光学性能,既能改善光散射性能也会提高强度性能,尤其是对于Sr改性填料。Zn改性填料使纸页结构变得更加开放,然而Sr改性填料使纸页结构更加封闭。对所有填料来说,压光会降低纸张松厚度,同时Sr改性PCC加填纸张的光学性能保持不变,但是研究发现纸张的光散射系数和强度性能会减小。因此,对这些填料加填纸张来说,应当优化压光条件。为了获得更高的折射率,应当考虑填料较高的改性级别。
PCC filler can be used to increase paper refractive index, the refractive index increase will further improve the paper optical properties. This paper investigates the potential of new PCC fillers with high refractive index for papermaking. PCC samples were prepared using the conventional carbonate method with the addition of a refractive index enhancing aid. The potential of PCC samples treated with mild Zn to papermaking was investigated. In addition to the Zn treatment, the effectiveness of Sr as a promoter was also investigated. Sr was found to change the morphology and crystal structure of the host particles. The effects of this kind of modification on paper light scattering coefficient, whiteness, opacity, tensile strength, bulk and porosity were described. The properties of paper before and after calendering were studied. Studies have shown that the modified filler is conducive to improving paper optical properties, both to improve the light scattering properties will also improve the strength properties, especially for Sr modified filler. The Zn-modified filler made the sheet structure more open, whereas the Sr-modified filler made the sheet structure more closed. For all fillers, calendaring reduced sheet bulk while the optical properties of Sr-modified PCC-filled sheets remained unchanged, but studies have found that the sheet’s light scattering coefficient and strength properties decrease. Therefore, for these fillers plus paper filling, the calendering conditions should be optimized. In order to obtain a higher refractive index, filler should be considered a higher level of modification.