The Overall Deacidification Of Ethylene Oxide On Paper Literature

There are massive quantities of books,archives and paper files all over the world.As we all know,it is easy for cellulose to degrade because of acid-catalyzed hydrolysis in preservation process.In this way,deacidification is the most important procedure for archive conservation and restoration.At the present,the normal deaicidification process needs to separate books or archives into pages in the deacidification solution.This method is time-consuming and energy-consuming,and breaks the original binding way.So books are likely to shrink,distort,and damage characters on paper.In addition,these methods just can be applicable for single-page.In short,mass deacidification is always a complex problem and challenge in archive conversation.Nowadays,the file archives,especially around 1949,are generally mixed by the alkaline and acidic papers in China.Vast papers,particularly the rare books in Ming and Qing dynasties are seriously acidified,which urgently require an applicable technology with pollution-free for deacidification and sterilization.To solve these problems,we designed an innovative process for mass deacidification and pollution-free sterilization by use of ethylene oxide.In this study,the design of the mass deacidification device based on ethylene oxide,deacidification mechanism,the effect of ethylene oxide on paper,the detection of residual of ethylene oxide and the conservationof the books after deacidificationwere studied.Based on these,we got the following conclusions:1.On account of the complexity of ancient books and archives,we chose four kinds of typical papers,including shengxuan paper,bamboo paper,printing paper and writing paper.The paper samples were treated by ethylene oxide.The mass deacidificationtechnology was optimized by evaluation index including color changes,pH values and mechanical properties.The best deaicidification condition is temperature/30?,RH/40%,ethylene oxide concentration 1.0 g/L and treatment for 10h.It was concluded that this deaicidification technology can deaicidify the whole book and alkila paper was not damaged.After treatment,pH of paper can be improved significantly to the neutral and alkalescency.Characters on paper will not change and the mechanical properties can also be improved mainly because ethylene oxide can form polymers to strengthen cellulose.In the meantime,these polymers can form hydrophobic protective film to improve the hydrophobicity of paper.In this way,paper can prevent swell and corrosion of cellulose and show well ageing resistance,better pH values,colors and mechanical properties under different artificial aging.2.From the microscopic view,we also studied influence of ethylene oxide deaicidification for different paper types.By testing the degree of polymerization(DP)of cellulose to reflect nature of paper ageing.The functional groups,crystal structure,thermo stability and morphology were tested by FTIR,XRD,TG,SEM,13C NMR andXPS.It was concluded that structure of cellulose of treated paper samples did not change.The degree of polymerization of deaicidified paper had higher retention rate with different ageing conditions.Compared with untreated paper samples,treatment with ethylene oxide had better ageing resistance.FTIR spectra showed that there was no new functional group after treatment with ethylene oxide.Analysis of XRD and 13C NMR illustrated ethylene oxide did not damage crystal structure of cellulosebutslow down the ageing process.Ethylene oxide can not only have ring opening reaction with free protons on paper,but also have desertification reaction withacidic functional group;furthermore,high-molecular polymer can also form on cellulose of paper to form a protective film rough.In this way,the bridge of polymerbetween cellulose fibersimprovesthe interaction of fibers.XPS analysis showed that the treatment of ethylene oxid did not caused an obvious change in the composition of the paper surface,but couldsignificant slow down the oxidation of paper in the process of aging.3.From the mass deaicidification by ethylene oxide,there was no any change on the color of the treated paper.Characters on paper also did not fade or diffuse according with the principle of restoration of cultural relic---repair the old as before.This technology does not need to separate books into single pages and not damage the original binding way of paper.Books did not shrink or change and characters did not fade or diffuse.This treatment can permeate completely.Eventually,the security of this treatment was analyzed.It was found that deaicidified books and paper did not have any ethylene oxide residues.The precious paper literature should be preserved effectively to prevent secondary acidification after the mass deacidification with ethylene oxide.Usually,there are three methods of paper files preservation in domestic and foreign,namely vacuum preservation,preservation in nitrogen and preservation with four special shelves.We tested the effect of the three preservations of the paper and found that the four special shelves are favourable for the long-term preservation of paper literature.The mass deacidification of paper by ethylene oxide can convert acid paper to neutral or weak alkaline,but without any impact for alkaline paper.This technology do not cause any wrinkle and deformation,harmful effect on the handwriting and color for paper because it avert the soaking of paper in the deacidification solution.The treated paper shows a certain anti-aging ability.This technology possess excellent efficacy for deacidification and protection of papers,which provide a reference to massively deacidify a large number of paper literature.