For treating paper with a methyltrimethoxysilane oligomer to improve its tensile strength after hydrolysis and poly-condensation of the oligomer, three types of treatment solutions were prepared which consisted of titanium butoxide, a standard amount of hydrochloric acid and a five-times excess amount of hydrochloric acid. The paper treated with titanium butoxide had a dramatically improved tensile strength compared to the base paper, and it reacted with the oligomer not in the ratio of 1 : 1, but as a reaction accelerator. Both hydrochloric acid catalyst solutions, on the other hand, turned the treated paper brown and decreased its tensile strength. Especially, the decrease was quite significant when an excess amount of acid was used. The FT-IR spectra of the acid treated paper showed the absorption at 1720 cm
−1 attributed to a carbonyl group resulting from the oxidation of cellulose, meaning that the cellulose molecules were decomposed by the acid, and this decomposition caused the decreased tensile strength. This result showed that the treatment solution consisting of hydrochloric acid could not be applied to paper due to its deterioration. On the other hand, the solution consisting of titanium butoxide could be successfully applied to it with a further improvement in its tensile strength.
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