Thesis (Ph. D.)--University of Washington, 2002. / Vita. Includes bibliographical references (leaves 70-73).

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Thesis (M.S.)--Miami University, Dept. of Paper Science and Engineering, 2003. / Title from first page of PDF document. Document formatted into pages; contains xii, 90 p. Includes bibliographical references (p. 88-90).

The adhesion of wet fibers is usually explained by the presence of capillary forces, which keep the swollen fibers together. These bonds are due to the free water present outside the wall of the swollen fibers. However, what happens when the free water is being removed and the tensile strength of the wet web continues to increase is not well understood. Tensile strength's measurements of refined fibers in presence of polyelectrolytes and mineral particles suggest that no enhancement of bonding occurs between the fibers when the free water is gone. The addition of microfibrils tends to enhance the wet web strength. This indicates strongly that fiber entanglement due to mechanical interactions may be the major interaction responsible for keeping the swollen fibers together in the transient region where neither capillary forces nor hydrogen bonding dominate. / The interactions between fibers, precipitated calcium carbonated (PCC) and retention aids, revealed that the wet web strength of PCC-filled handsheets is detrimental in the presence of flocculated PCC particles, while no detrimental effect is observed in the presence of stable PCC particles. Friction generated by the deposition of small and/or single particles on the fiber surface can explain their enhancement of strength, whereas bigger particles may prevent the entanglement of fibers. Finally, the addition of polyelectrolytes to swollen fibers reduces the wet web strength. The presence of an additional polymer layer results in an increased electrosteric repulsion between fibers, which decreases the friction between fibers. This reduction of friction makes the fibers slide more easily over each other, resulting in poor wet web strength.

Thesis (Ph. D.)--University of Minnesota, 1927. / Biography. Bibliography: p. 23-24.

Calcium carbonate is one of the preferred fillers for the paper industry. This research compared the physical and chemical properties of calcium carbonates produced by different methods and their use with a novel rosin sizing system. The effectiveness of a polymeric retention agent, which flocculates particles during paper production, has also been examined.

Thesis (MScFor)--Stellenbosch University, 2005. / ENGLISH ABSTRACT: The retention of filler particles and drainage are important aspects of papermaking. A number of important paper properties depend in the quality and quantity of filler retained in the paper. Fines, fillers and pulp fibres all have a negative charge and are kept apart by electrostatic forces. This causes a decrease in the effectiveness of cationic retention aids thereby causing a high cationic demand. This in turn implies that the retention of fines and filler particles in a formed sheet is not efficient, especially in the presence of anionic trash. In order to improve printability, print quality and dimensional stability, a large percentage of mineral pigments / fillers either in the form of internal loading or external coating should be added. It was found that coflocculation of fines and filler particles resulted in an even distribution of filler particles in the form of miero-flocs and the filler retention was maintained. Opacity was improved without much reduction in paper strength. An increased filler content without coflocculation of fines reduced sheet strength properties. The filler particles interfered with the development of fibre-to-fibre bonds and occupied spaces that otherwise might have contained fibres. This study showed that the most beneficial effect of coflocculation of filler with fines was obtained, with regards to paper strength, opacity, filler retention and printability, when the charge of the fibre furnish was maintained at -0.1 leu with the 0.1% addition of cationic PAM retention aid. / AFRIKAANSE OPSOMMING: Twee belangrike aspekte van papiervervaardiging is die retensie van vulstowwe en ontwatering. 'n Aantal belangrike papiereienskappe is afhanklik van die hoeveelheid en kwaliteit van vulstowwe wat in papier voorkom. Veselpuin, vulstowwe en pulp-vesels is almal negatief gelaai, gevolglik verseker elektrostatiese kragte dat hierdie deeltjies los van mekaar bly. Laasgenoemde verminder die doeltreffendheid van kationiese retensiemiddels en dit gee aanleiding tot 'n hoë kationiese aanvraag. Die retensie van veselpuin en vulstof deeletjies in papier is gewoonlik nie voldoende in die teenwoordigheid van anioniese afvalkomponente nie. Om aan papier verbeterde drukeienskappe, drukkwaliteit en dimensionele stabiliteit te gee, moet 'n groot persentasie minerale pigmente en/of vulstowwe as 'n interne lading of eksterne bestryking voorsien word. Daar is bevind dat kot1okkulasie van fynstowwe en vulstofdeeltjies, 'n egalige verspreiding van vulstof-partikels as mikro-t1okke tot gevolg het en dat vulstof-retensie op aanvaarbare vlakke behou is. Ook is ondeurskynendheid verbeter sonder 'n beduidende verswakking in die papiersterkte. 'n Toename in vulstofinhoud, sonder kot1okkulasie van fynstowwe, het die papier sterkte-eienskappe verlaag. Vulstofdeeltjies bëinvloed die ontwikkeling van vesel-tot-vesel binding. Hierdie deeltjies beset ruimtes wat andersins deur vesels benut sou word. Hierdie studie het getoon dat die voordeligste effek van kot1okkulasie van vulstowwe met fynstowwe verkry is, ten opsigte van papiersterkte, ondeurskynendheid, vulstof retensie en drukeienskappe, wanneer die lading van die pulpsuspensie by -0.1 leu gehou was met 'n byvoeging van 0.1% kationiese PAM retensie-hulpmiddel.

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ABSTRACT Papermaking is one of the four major inventions of our country, and is also the index for the cultural life level and economic development in one country. Trade is the main dependence for Taiwan to maintain survival, especially at the beginning of the 21st century. Our country has been listed as the 14th trade country globally, which shows the importance of international trade to Taiwan. WTO is the most important international trade organization at present. In 2002, there are 144 member countries covering 90% trade of the whole world; that is why it is called economic and trading United Nations. This study first gives a brief introduction to the history of WTO. Then it discusses the basic idea of WTO, i.e. there is non-discrimination trade, the market is opened through negotiation, fair competition is promoted, development and economic transformation are encouraged. It also introduces the four basic principles, i.e. the most preferential country treatment, national treatment, trade freedom, transparency and being predictable. Concerning the function of WTO, it also describes dispute solution rules, main organizations and responsibilities of WTO. It discusses the influence on our country and corresponding measures after entering WTO. The study analyzes the status quo of papermaking industry. First, it analyzes the status quo of papermaking industry worldwide. In 2000, the top five countries in the world paper pulp production are USA, Canada, China, Finland, and Sweden. The top five countries in paper and paper board production are USA, Japan, China, Canada, Germany, while Taiwan is listed as the top 16 production country. The annual paper usage amount per capita represents the level of culture, living standard and as an important index of economic development for a country. The top five countries are Finland, Belgium, USA, Sweden and Holland, while Taiwan is ranked as the 9th, a country with high cultural living standard and industrial development. This study gives a systematic description of Taiwan papermaking industry after analyze papermaking globally. Ever since Ching Dynasty, Taiwan papermaking has 130 years of history. During the initial stage, it used bamboo to make paper, and later cane dregs. As Taiwan is lacking of natural forest resources, which forced Taiwan papermaking industry to research and develop and become a country with the highest waste paper recovery rate and utilization rate worldwide. It made full use of waste paper as the raw material, to develop the unique papermaking core technique and competitiveness. As Taiwan has entered into WTO and become closely connected with the world, this study gives In-depth discussion and description about the strength, weakness, opportunities, and threats of Taiwan papermaking industry. It also provides corresponding measures for reference to papermaking industry and the government. Key Words: WTO¡BPAPERMAKING INDUSTRY¡BTAIWAN