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Although the title of this book is Paper Chemistry, it should be considered as a text about the chemistry of the formation of paper from aqueous suspensions of fibre and other additives, rather than as a book about the chemistry of the raw material itself. It is the subject of what papermakers call wet-end chemistry. There are many other excellent texts on the chemistry of cellulose and apart from one chapter on the accessibility of cellulose, the subject is not addressed here. Neither does the book deal with the chemistry of pulp preparation (from wood, from other plant sources or from recycled fibres), for there are also many excellent texts on this subject. The first edition of this book was a great success and soon became established as one of the Bibles of the industry. Its achievement then was to collect the considerable advances in understanding which had been made in the chemistry of papermaking in previous years, and provide, for the first time, a sound physico chemical basis of the subject. This new edition has been thoroughly updated with much new material added. The formation of paper is a continuous filtration process in which cellulosic fibres are formed into a network which is then pressed and dried. The important chemistry involved in this process is firstly the retention of col loidal material during filtration and secondly the modification of fibre and sheet properties so as to widen the scope for the use of paper and board products."
The verrucarins and roridins are secondary metabolites of the soil fungi Myrothecium verrucaria (Albertini et Schweinitz) Ditmar ex Fries and Myrothecium roridum Tode ex Fries. The species Myrothecium belongs to the fungi imperfecti, order of Moniliales, family Tubercularia- ceae (30, 17, 32). The distinction between these and other closely related fungal species is difficult. It has been studied and discussed by various authors (82, 16, 55, 75, 62, 43). Myrothecium species are parasitic on leaves of Gardenia, tomatoes, violets, kidney beans, snapdragons and other common plants. They are also found on decaying tissue and in soil. It was known earlier that cultures of the two species mentioned exhibit cellulolytic properties due to the presence of a very active cellulase which was used for the treatment of cellulose during the production of textiles [for leading references see (42, 66)]. The first investigation of the secondary metabolites of these micro- organisms was carried out by BRIAN and MCGOWAN (16). They isolated a crystalline compound, designated as glutinosin and assigned the formula C4sH60016, from cultures of Metarrhizium glutinosum S. Pope, which in fact is a Myrothecium species (82, 55). Glutinosin exhibited anti- fungal activity. Eight years later BOWDEN and SCHANTZ (14) described the isolation and characterization of a dermatitic or skinirritating crystal- line compound melting at 38 , and possessing the formula C H 04, 1s 22 from culture filtrates of Myrothecium verrucaria. They suspected the presence of additional biologically active substances.
Although the title of this book is Paper Chemistry, it should be considered as a text about the chemistry of the formation of paper from aqueous suspensions of fibre and other additives, rather than as a book about the chemistry of the raw material itself. It is the subject of what papermakers call wet-end chemistry. There are many other excellent texts on the chemistry of cellulose and apart from one chapter on the accessibility of cellulose, the subject is not addressed here. Neither does the book deal with the chemistry of pulp preparation (from wood, from other plant sources or from recycled fibres), for there are also many excellent texts on this subject. The first edition of this book was a great success and soon became established as one of the Bibles of the industry. Its achievement then was to collect the considerable advances in understanding which had been made in the chemistry of papermaking in previous years, and provide, for the first time, a sound physico chemical basis of the subject. This new edition has been thoroughly updated with much new material added. The formation of paper is a continuous filtration process in which cellulosic fibres are formed into a network which is then pressed and dried. The important chemistry involved in this process is firstly the retention of col loidal material during filtration and secondly the modification of fibre and sheet properties so as to widen the scope for the use of paper and board products."
For what is thought of as an essentially mechanical process, paper manufacture involves a large amount of chemistry. The Chemistry of Paper provides an overview of the process of making paper from a chemical perspective. It deals with both the chemistry of paper as a material and the chemistry of its production, setting out the main principles involved at every stage of the process. Early chapters provide a chemical definition of paper in the light of the many uses to which it is put. Subsequent chapters deal with the chemical processes involved in the production of paper: the delignification of the wood fibres performed at elevated temperature and pressure, the bleaching of the cellulose-rich pulp using environmentally-friendly systems, the formation of the pulp into sheets of fibres strengthened by extensive inter-fibre hydrogen bonding, and finally the coating of the sheets in a manner appropriate to their end use. Chemistry is involved at every stage of the process, including carbohydrate chemistry, the chemistry of inorganic pigments and organic resins, colloid and surface chemistry, as well as elements of environmental and analytical chemistry. The Chemistry of Paper provides an informative and entertaining overview of the chemical principles involved. It will be especially suitable for students and others who require an introduction to the chemistry of paper manufacture.
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