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This work has been conducted to investigate the effect of accelerated ageing on the filler-free (control) handsheets and the ones having Precipitated Calcium Carbonate (PCC) and Zeolite (Clinoptilolite) fillers. The diagnosis approach of this work has been based on the use of the techniques of attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and X-ray diffraction (XRD). The FT-IR technique has allowed identifying the changes in cellulose components of handsheets. Likewise, the XRD technique has provided to diagnose the changes in crystallinity of the handsheets and fillers. The results found out that PCC and Zeolite fillers could be easily added to the structure of the paper network by changing various experimental variables. The loss of C−O functional groups and the formation of carbonyl groups in handsheets has been analysed by accelerated ageing. The spectroscopy results confirmed that usage of zeolite filler has a retarding and structurally improving effect on the glycosidic linkages. Recent findings have been provided new insights into the role of the synergistic effect of the combination of PCC and zeolite fillers in the decelerating of certain ageing mechanism. [ABSTRACT FROM AUTHOR]

The focus of this research is the stabilisation of paper with Verdigris, a green copper pigment. Due to its corrosive effects on paper, many important documents, paintings and maps are in danger. The efficiency of several commercially available deacidification agents on paper samples with Verdigris was tested, including magnesium-based Bookkeeper® dispersion, nano calcium hydroxide containing Nanorestore® and CaLoSiL® dispersions as well as a recently developed dispersion of nano calcium carbonate. The antioxidant tetrabutylammonium bromide was tested either alone or in combination with nano calcium based deacidification agents. The effect of the treatments was evaluated using colour, tensile strength, degree of polymerization and pH measurements. The results indicate that acidic degradation does not play a major role during accelerated degradation of paper containing Verdigris with moderately acidic pH value and that oxidative decay could be the main culprit of the decay. The method described, which involves the use of antioxidant tetrabutylammonium bromide in combination with calcium carbonate based deacidification dispersion, was proved to have a superior effect against degradation of paper with Verdigris in comparison to the treatments which involve deacidification agents only. Nano calcium hydroxide based deacidification agents result in high pH values of the paper samples and therefore cannot be advised for use on paper documents. [ABSTRACT FROM AUTHOR]

A composite filler was developed by pre-flocculation of fiber fines and precipitated calcium carbonate (PCC) particles with flocculants such as cationic polyacrylamide (cPAM) and bentonite. The composite filler was compared with a conventional loading method in terms of physical properties of handsheet and filler retention. The handsheets using the composite filler showed higher strength properties than that using a conventional loading at a similar paper ash content level, implying that paper ash content can be increased maintaining same level of paper strength. Optical properties such as opacity and brightness of the paper with the composite were quite similar with the paper with the conventional loading. Filler retention of the composite filler was slightly higher than that of the conventional loading even though retention aids were not used for the composite filler. Paper formation of the composite filler was better than the case of the conventional loading. However, the sheet with the composite filler showed lower bulk than that with the conventional loading. Conclusively, the composite filler technology by pre-flocculation of fines and filler has a potential to be utilized to produce a high loaded paper. [ABSTRACT FROM AUTHOR]