Date of Award


Degree Name

Bachelor of Science


Pulp and Paper Technology


Until the recent time hemicelluloses were regarded as an undesirable part of the cellulose fiber; the most desirable fiber for paper-making purposes was believed to be one containing 100% pure cellulose. This theory is fallacious, since it is now known that hemicellulose plays a major role in paper-making and in fact, a satisfactory paper cannot be formed from wood pulp without some hemicellulosic material being present. The best pulp is one which has been cooked to remove most of the lignin, but not so drastically cooked as to degrade the cellulose or remove too much of the hemicellulose fraction. Such a pulp will beat easily and have good strength characteristics, because a high proportion of the rapid beating hemicelluloses are left in the pulp. Because of the relationship between hemicellulose content and paper-making qualities of the pulp and also because of the economic factors involved, pulp chemists have turned their attention to the production of pulps containing the highest possible proportion of the carbohydrate constituents of the original wood. Since the hemicelluloses are such an important part of the paper-making material it is desirable to determine their fate during bleaching. This is especially true since the trend in modern paper-making is to obtain a brighter and stronger pulp and paper.