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A study of the sodium aluminate-abietate size precipitatesGuide, Robert G. 01 January 1959 (has links)
No description available.
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Glycoside production by in vitro <em>Rhodiola rosea</em> culturesGyörgy, Z. (Zsuzsanna) 22 May 2006 (has links)
Abstract
Rhodiola rosea is a medicinal plant, mainly used in Asia and Scandinavia. It is characterized as an adaptogen and is reported to have many pharmacological properties, which are ascribed to the glycosides of cinnamyl alcohol and tyrosol. As natural habitats are already overharvested and the cultivation of this plant needs 4–6 years, the production of the pharmacologically important compounds in in vitro cultures could be an alternative. In the work presented here, the production of these glycosides in compact callus aggregate cultures of roseroot was addressed.
Biotransformation of exogenously added cinnamylalcohol and tyrosol was studied. Glucosylation of the precursors yielded high amounts of rosin and salidroside and low amounts of rosavin. During the course of this work, four new glycosides of cinnamyl alcohol were found and identified. The optimal concentration of the precursors and the time needed for the biotransformation was also determined. For enhancing the biotransformation rate, glucose was added to the culture medium alongside with sucrose, which doubled the production of cinnamyl alcohol glycosides but did not affect the production of salidroside. A pilot experiment using air-lift bioreactor was performed.
A cDNA fragment encoding tyrosine decarboxylase was isolated and described. The expression of this gene was analysed in the leaves and roots of two chemotypes. The results demonstrate the important role of tyrosine decarboxylase in the production of salidroside.
The results revealed production of the pharmacologically important glycosides of Rhodiola rosea; however the successful pilot bioreactor experiment remains to be scaled-up. New information was obtained on the biosynthesis of salidroside, which substantiate the metabolic engineering of roseroot.
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An investigation of the association of colonic adenomatous polyps and nutritional status of retinol and caroteneMagnetti, Cecilia Ann January 1985 (has links)
The hypothesis was evaluated that lower dietary consumption of carotene or retinol or lower serum levels of beta carotene or retinol are associated with development of colonic adenomas. To evaluate this hypothesis, selected patients who were to undergo colonoscopy to determine polyps status were asked to undergo a battery of tests to assess nutritional status. These tests included a dietary and demographic questionnaire, serologic assessment of beta carotene and retinol, and a dark adaptation test.
One hundred male subjects were evaluated. Fifty-seven were found to have colonic adenomatous polyps. Cases and controls appeared to be well matched for demographic characteristics. There were no statistically significant differences for any nutritional parameter between cases and controls, but cigarette smoking was more prevalent among cases than controls (p<0.05).
Because nonsignificant negative associations with colonic adenomas were observed for some of the nutritional parameters, it is concluded that additional subjects should be studied, as planned. / M.S.
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Evaluation and performance prediction of cooling tower rain zonesPierce, Darren John 03 1900 (has links)
Thesis (MScEng (Mechanical and Mechatronic Engineering))--University of Stellenbosch, 2007. / Cooling tower rain zone performance characteristics such as the loss coefficient
and the Merkel number are evaluated and simulated. To this end the influence of
drop diameter and drop deformation on the velocity, path length and cooling of
single water drops are investigated. Experimental drop size and pressure drop data
over a counterflow rain zone are presented and the effect of drop deformation on
the pressure drop is investigated using the experimental data and CFD. Using the
experimental drop size data and CFD, the performance uncertainty produced by
using the Rosin-Rammler drop distribution function as opposed to the discrete
drop distribution data is investigated. CFD models are developed to investigate
the feasibility of modelling rain zones by assuming a constant drop diameter and
to establish which diameter definition is the most representative of a particular
polydisperse drop distribution. These models were used to validate the
correlations for the rain zone performance characteristics proposed in literature.
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Decay and environmental studies on southern pineDahlen, Joseph Martin 10 December 2010 (has links)
This work focused on decay and dimensional stability of southern pine lumber and environmental issues associated with emissions released during kiln drying of southern pine. In one study decking boards were treated with a 3% resin acid solution to increase the dimensional stability. The boards were placed on a roof and weathered for two years. The increased water repellency reduced moisture gain following summer rainstorms by one-third compared to untreated matched samples, this significantly reduced splitting by half and cupping by one-third. In one study decking boards from matched samples were weathered for two years in the roof setup described above, and in a fungal ground proximity test. The ground proximity samples had slightly more decay than the roof samples. Correlation between decay ratings for the matched samples was 37%, suggesting above-ground decay susceptibility is dependent on the macro- and micro-environment. Decay in roof exposure was modeled based on moisture content factors, whereas decay in ground proximity was modeled by the resin and fatty acids. One study tested pole sections with varying amounts of sapwood, heartwood, and knots dried in a pilot-scale kiln. A sample of the kiln exhaust was measured for volatile organic compounds. Emissions from poles were similar to clear lumber. Emissions from heartwood poles were less than for heartwood lumber, perhaps due to the poles’ sapwood band. The final study was conducted with clear and knotty lumber kiln dried to below 8% moisture content using three kiln schedules. Wood dried to this lower moisture content is used in interior applications or exported. During drying, a sample of the kiln exhaust was analyzed for total VOCs, and a sample of the kiln exhaust was collected and analyzed for hazardous air pollutants via gas chromatography and spectrophotometry. For all three kiln schedules, mills would reach 10 tons of methanol and thus must comply with maximum achievable control technology standards before reaching 25 tons of methanol, formaldehyde, acetaldehyde, acrolein, and propionaldehyde.
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Aditivación de materiales biodegradables mediante el uso de derivados de colofoniaPavón Vargas, Cristina Paola 16 January 2023 (has links)
[ES] El objetivo general de la presente tesis doctoral fue aditivar polímeros biodegradables con colofonia y sus derivados mediante el uso de técnicas de procesamiento convencionales y no convencionales. En esta tesis se presentan siete trabajos dentro de cuatro bloques de estudio que constituyeron los objetivos específicos de la investigación. En el primer bloque de estudio se realizó una caracterización comparativa de cinco colofonias de diferentes fuentes para determinar sus propiedades y establecer las diferencias entre cada colofonia para su posterior uso y aplicación como aditivos sostenibles de polímeros biodegradables. En el segundo bloque de estudio se aditivó colofonia en matrices de polímeros biodegradables para lo cual se realizaron dos trabajos. En el primer trabajo se empleó poli (butilen adipato-co-tereftalato) (PBAT) como matriz polimérica y colofonia (GR) y un pentaeritritol éster de colofonia (UT) como aditivos. El PBAT se mezcló con las resinas en varios contenidos y las formulaciones se procesaron por extrusión y un posterior moldeo por inyección. En el segundo trabajo se empleó poli(¿-caprolactona) (PCL) como matriz polimérica, y como aditivos se emplearon GR y cera de abeja (BW). Las formulaciones se prepararon por mezcla por extrusión y el procesamiento del material se llevó a cabo por una técnica no convencional que es la manufactura aditiva o impresión 3D.En el tercer bloque de estudio se realizó la aditivación de materiales termoplásticos utilizando como base un polímero biodegradable de alto rendimiento ambiental y como aditivo colofonia y sus derivados. Como polímero base se empleó almidón termoplástico (TPS) y como aditivos de usaron los siguientes derivados de colofonia: colofonia sin modificar (GR), colofonia deshidrogenada (RD), colofonia modificada con anhidrido maleico (CM), pentaeritritol éster (LF) y éster de glicerol de colofonia (UG). La colofonia se mezcló con el TPS por extrusión y el procesamiento de las mezclas se llevó a cabo por moldeo por inyección. En el cuarto bloque se estudió la aditivación de colofonia a matrices poliméricas mediante la técnica de electropulverización. Se realizaron tres trabajos en los que se optimizó e implementó el proceso de electrospulverización para la incorporación de microesferas de colofonia en matrices poliméricas. En el primer trabajo se evalúo el uso de un proceso electrohidrodinámico como método de aditivación de colofonia en matrices poliméricas. En el segundo trabajo se optimizó el proceso de electropulverización de colofonia a partir de 24 experimentos. Posteriormente, se depositaron microesferas de GR sobre películas de PCL para obtener sistemas bicapa. Los resultados obtenidos revelaron un gran potencial para procesar fácilmente sistemas bicapa con alto interés en aplicaciones agrícolas, de empaque y/o biomédicas sostenibles. Finalmente, en el tercer trabajo se usó el método optimizado de electrospraying para aditivar microesferas de colofonia sobre la capa exterior de una mascarilla quirúrgica a base de polipropileno (PP), y se determinó que el revestimiento de microesferas ayudó a mantener la hidrofobicidad original de la capa exterior de la mascarilla quirúrgica incluso después de 6 horas de uso, aumentando en el tiempo de vida útil de la mascarilla. Los resultados de la tesis indican que la colofonia y sus derivados son versátiles como aditivos de matrices termoplásticas biodegradables y que el proceso de aditivación puede llevarse a cabo por métodos de procesamiento tanto convencionales como no convencionales. Los hallazgos del estudio son significativos porque la colofonia es un material natural obtenido de fuentes renovables, no es tóxica y es biocompatible, de modo que su uso como aditivo no solo mejora las propiedades de los polímeros biodegradables, sino que promueve el estudio y desarrollo de materiales sostenibles lo que contribuye a la disminución del impacto ambiental de los plásticos. / [CA] L'objectiu general de la present tesi doctoral va ser additivar polímers biodegradables amb colofònia i els seus derivats mitjançant l'ús de tècniques de processament convencionals i no convencionals. En aquesta tesi es presenten set treballs dins de quatre blocs d'estudi que van constituir els objectius específics de la investigació. En el primer bloc d'estudi es va realitzar una caracterització comparativa de cinc colofònies de diferents fonts, per a determinar les seues propietats i establir les diferències entre cada colofònia per al seu posterior ús i aplicació com a additius sostenibles de polímers biodegradables. En el segon bloc d'estudi es additivar colofònia en matrius de polímers biodegradables, per a això es van realitzar dos treballs. En el primer treball es va emprar poli (butilen adipat-co-tereftalat) (PBAT) com a matriu polimèrica i colofònia (GR) i un pentaeritritol èster de colofònia (UT) com a additius. El PBAT es va mesclar amb les resines en diversos continguts i les formulacions es van processar per extrusió i un posterior emotlament per injecció. En el segon treball es va emprar poli(¿-caprolactona) (PCL) com a matriu polimèrica, i com a additius es van emprar GR i cera d'abella (BW). Les formulacions es van preparar per mescla per extrusió i el processament del material es va dur a terme per una tècnica no convencional que és la manufactura additiva o impressió 3D. En el tercer bloc d'estudi es va realitzar l'additivació de materials termoplàstics utilitzant com a base un polímer biodegradable d'alt rendiment ambiental i com a additiu colofònia i els seus derivats. Com a polímer base es va emprar midó termoplàstic (TPS) i com a additius de van usar els següents derivats de colofònia: colofònia sense modificar (GR), colofònia deshidrogenada (RD), colofònia modificada amb anhidrido maleic (CM), pentaeritritol èster (LF) i èster de glicerol de colofònia (UG). La colofònia es va mesclar amb el TPS per extrusió i el processament de les mescles es va dur a terme per emotlament per injecció. En el quart bloc es va estudiar l'additivació de colofònia a matrius polimèriques mitjançant la tècnica d'electrospulverització. Es van realitzar tres treballs en els quals es va optimitzar i va implementar el procés d'electrospulverització per a la incorporació de microesferes de colofònia en matrius polimèriques. En el primer treball s'avalue l'ús d'un procés electrohidrodinàmic com a mètode d'additivació de colofònia en matrius polimèriques i es van obtindre tant microesferes com microfibres de colofònia depenent de la concentració de la solució inicial. En el segon treball es va optimitzar el procés d'electrospulverització de colofònia a partir de 24 experiments. Posteriorment, les microesferes de GR es van depositar sobre pel·lícules de per a obtindre sistemes bicapa. Els resultats obtinguts van revelar un gran potencial per a processar fàcilment sistemes bicapa. Finalment, en el tercer treball es va usar el mètode optimitzat d'electrospulverització per a additivar microesferes de colofònia sobre la capa exterior d'una màscara quirúrgica a base de polipropilè (PP), i es va determinar que el revestiment de microesferes va ajudar a mantindre la hidrofobicitat original de la capa exterior de la màscara quirúrgica. Els resultats de la tesi indiquen que la colofònia i els seus derivats són versàtils com a additius de matrius termoplàstiques biodegradables i que el procés de d'additivació pot dur-se a terme per mètodes de processament tant convencionals com no convencionals. Les troballes de l'estudi són significatius perquè la colofònia és un material natural obtingut de fonts renovables, no és tòxica i és biocompatible, de manera que el seu ús com a additiu no sols millora les propietats dels polímers biodegradables, sinó que promou l'estudi i desenvolupament de materials sostenibles el que contribueix a la disminució de l'impacte ambiental dels plàstics / [EN] The general objective of this doctoral thesis was to add biodegradable polymers with gum rosin and its derivatives, using conventional and unconventional processing techniques. This thesis presents seven works within four study blocks that constitute the specific objectives of the research. The first study block conducts a comparative characterization of five gum rosins from different sources to determine their properties and establish the differences between each rosin for their subsequent use and application as sustainable additives for biodegradable polymers. The second study block examines the compounding of biodegradable polymer matrices with gum rosin, for which two works were developed. The first work uses poly (butylene adipate-co-terephthalate) (PBAT) as the polymeric matrix and rosin (GR) and a rosin pentaerythritol ester (UT) as additives. PBAT was mixed with the resins in various contents, and the formulations were processed by extrusion and subsequent injection molding. The second work uses poly(¿-caprolactone) (PCL) as a polymeric matrix and GR and beeswax (BW) as additives. The three materials mentioned are biocompatible and biodegradable. The formulations were mixed by extrusion, and the material was processed by an unconventional technique: additive manufacturing or 3D printing. The third study block compounded thermoplastic materials using a biodegradable polymer with high environmental performance as a base and gum rosin and its derivatives as additives. This study used thermoplastic starch (TPS) as the base polymer and the following gum rosin derivatives were used as additives: unmodified rosin (GR), dehydrogenated rosin (RD), rosin modified with maleic anhydride (CM), pentaerythritol ester (LF) and ester of rosin glycerol (UG). Gum rosin and TPS were mixed by extrusion and processed by injection molding. The fourth study block studies the addition of rosin to polymeric matrices using the electrospraying technique. Three works were carried out to optimize and implement the electrospraying process for adding rosin microspheres in polymeric matrices. The first work evaluated the use of an electrohydrodynamic process to add gum rosin to polymeric matrices. The process allowed gum rosin microspheres and microfibers depending on the concentration of the initial solution. The second work optimized the gum rosin electrospraying process from 24 experiments. Subsequently, GR microspheres were deposited on compression molded PCL films to obtain bilayer systems. The results revealed a great potential to efficiently process bilayer systems with high interest in sustainable agricultural, packaging, and/or biomedical applications. Finally, the third work used the optimized electrospraying method to add gum rosin microspheres to the outer layer of polypropylene (PP)-based surgical mask. The results showed that the microsphere coating helped maintain the original hydrophobicity of the outer layer of the surgical mask. The thesis results indicate that gum rosin and its derivatives are versatile as additives in biodegradable thermoplastic matrices and that both conventional and unconventional processing methods can carry out the additive process. The study findings are significant because rosin is a natural material obtained from renewable sources; it is non-toxic and biocompatible. Therefore, using gum rosin as an additive not only improves the properties of biodegradable polymers but also promotes the study and development of sustainable materials, which contributes to reducing the environmental impact of plastics. / Gracias a la Conselleria de Innovación, Universidades, Ciencia y Sociedad Digital, por la
beca otorgada (GRISOLIAP/2019/113), que me ha permitido dedicarme completamente a
la realización de este proyecto.
A la Conselleria de Innovación, Universidades, Ciencia y Sociedad Digital por la
ayuda para “Subvenciones para estancias de contratados predoctorales en centros de
investigación fuera de la Comunitat Valenciana (BEFPI)” (CIBEFP/2021/30) / Pavón Vargas, CP. (2022). Aditivación de materiales biodegradables mediante el uso de derivados de colofonia [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/191385
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Physico-Chemical Processes during Reactive Paper Sizing with Alkenyl Succinic Anhydride (ASA) / Physikochemische Prozesse während der Reaktivleimung mit Alkenyl-Bernsteinsäure-Anhydrid (ASA)Porkert, Sebastian 27 February 2017 (has links) (PDF)
Sizing (hydrophobization) is one of the most important process steps within the added-value chain of about 1/3rd of the worldwide produced paper & board products. Even though sizing with so-called reactive sizing agents, such as alkenyl succinic anhydride (ASA) was implemented in the paper industry decades ago, there is no total clarity yet about the detailed chemical and physical mechanisms that lead to their performance. Previous research was carried out on the role of different factors influencing the sizing performance, such as bonding between ASA and cellulose, ASA hydrolysis, size revision as well as the most important interactions with stock components, process parameters and additives during the paper making process. However, it was not yet possible to develop a holistic model for the explanation of the sizing performance given in real life application. This thesis describes a novel physico-chemical approach to this problem by including results from previous research and combining these with a wide field of own basic research and a newly developed method that allows tracing back the actual localization of ASA within the sheet structure.
The carried out measurements and trial sets for the basic field of research served to evaluate the stock and process parameters that most dominantly influence the sizing performance of ASA. Interactions with additives other than retention aids were not taken into account. The results show that parameters, such as the content of secondary fibers, the degree of refining, the water hardness as well as the suspension conductivity, are of highest significance. The sample sets of the trials with the major impacting parameters were additionally analyzed by a newly developed localization method in order to better understand the main influencing factors.
This method is based on optical localization of ASA within the sheet structure by confocal white light microscopy. In order to fulfill the requirements at magnification rates of factor 100 optical zoom, it was necessary to improve the contrast between ASA and cellulose. Therefore, ASA was pretreated with an inert red diazo dye, which does not have any impact on neither the sizing nor the handling properties of ASA. Laboratory hand sheets that were sized with dyed ASA, were analyzed by means of their sizing performance in correlation to measurable ASA agglomerations in the sheet structure. The sizing performance was measured by ultrasonic penetration analysis. The agglomeration behavior of ASA was analyzed automatically by multiple random imaging of a sample area of approx. 8650 µm² with a minimum resolution for particles of 500 nm in size. The gained results were interpreted by full factorial design of experiments (DOE). The trials were carried out with ASA dosages between 0% and 0.8% on laboratory hand sheets, made of 80% bleached eucalyptus short fiber kraft pulp and 20% northern bleached softwood kraft pulp, beaten to SR° 30, produced with a RDA sheet former at a base weight of 100 g/m² oven dry.
The results show that there is a defined correlation between the ASA dosage, the sizing performance and the number and area of ASA agglomerates to be found in the sheet structure. It was also possible to show that the agglomeration behavior is highly influenced by external factors like furnish composition and process parameters. This enables a new approach to the explanation of sizing performance, by making it possible to not only examine the performance of the sizing agent, but to closely look at the predominant position where it is located in the sheet structure. These results lead to the explanation that the phenomenon of sizing is by far not a pure chemical process but rather a more physical one. Based on the gained findings it was possible so far to optimize the ASA sizing process in industrial-scale by means of ~ 50% less ASA consumption at a steady degree of sizing and improved physical sheet properties.
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Physico-Chemical Processes during Reactive Paper Sizing with Alkenyl Succinic Anhydride (ASA)Porkert, Sebastian 09 December 2016 (has links)
Sizing (hydrophobization) is one of the most important process steps within the added-value chain of about 1/3rd of the worldwide produced paper & board products. Even though sizing with so-called reactive sizing agents, such as alkenyl succinic anhydride (ASA) was implemented in the paper industry decades ago, there is no total clarity yet about the detailed chemical and physical mechanisms that lead to their performance. Previous research was carried out on the role of different factors influencing the sizing performance, such as bonding between ASA and cellulose, ASA hydrolysis, size revision as well as the most important interactions with stock components, process parameters and additives during the paper making process. However, it was not yet possible to develop a holistic model for the explanation of the sizing performance given in real life application. This thesis describes a novel physico-chemical approach to this problem by including results from previous research and combining these with a wide field of own basic research and a newly developed method that allows tracing back the actual localization of ASA within the sheet structure.
The carried out measurements and trial sets for the basic field of research served to evaluate the stock and process parameters that most dominantly influence the sizing performance of ASA. Interactions with additives other than retention aids were not taken into account. The results show that parameters, such as the content of secondary fibers, the degree of refining, the water hardness as well as the suspension conductivity, are of highest significance. The sample sets of the trials with the major impacting parameters were additionally analyzed by a newly developed localization method in order to better understand the main influencing factors.
This method is based on optical localization of ASA within the sheet structure by confocal white light microscopy. In order to fulfill the requirements at magnification rates of factor 100 optical zoom, it was necessary to improve the contrast between ASA and cellulose. Therefore, ASA was pretreated with an inert red diazo dye, which does not have any impact on neither the sizing nor the handling properties of ASA. Laboratory hand sheets that were sized with dyed ASA, were analyzed by means of their sizing performance in correlation to measurable ASA agglomerations in the sheet structure. The sizing performance was measured by ultrasonic penetration analysis. The agglomeration behavior of ASA was analyzed automatically by multiple random imaging of a sample area of approx. 8650 µm² with a minimum resolution for particles of 500 nm in size. The gained results were interpreted by full factorial design of experiments (DOE). The trials were carried out with ASA dosages between 0% and 0.8% on laboratory hand sheets, made of 80% bleached eucalyptus short fiber kraft pulp and 20% northern bleached softwood kraft pulp, beaten to SR° 30, produced with a RDA sheet former at a base weight of 100 g/m² oven dry.
The results show that there is a defined correlation between the ASA dosage, the sizing performance and the number and area of ASA agglomerates to be found in the sheet structure. It was also possible to show that the agglomeration behavior is highly influenced by external factors like furnish composition and process parameters. This enables a new approach to the explanation of sizing performance, by making it possible to not only examine the performance of the sizing agent, but to closely look at the predominant position where it is located in the sheet structure. These results lead to the explanation that the phenomenon of sizing is by far not a pure chemical process but rather a more physical one. Based on the gained findings it was possible so far to optimize the ASA sizing process in industrial-scale by means of ~ 50% less ASA consumption at a steady degree of sizing and improved physical sheet properties.:Acknowledgment I
Abstract III
Table of Content V
List of Illustrations XI
List of Tables XVI
List of Formulas XVII
List of Abbreviations XVIII
1 Introduction and Problem Description 1
1.1 Initial Situation 1
1.2 Objective 2
2 Theoretical Approach 3
2.1 The Modern Paper & Board Industry on the Example of Germany 3
2.1.1 Raw Materials for the Production of Paper & Board 5
2.2 The Sizing of Paper & Board 8
2.2.1 Introduction to Paper & Board Sizing 8
2.2.2 The Definition of Paper & Board Sizing 10
2.2.3 The Global Markets for Sized Paper & Board Products and Sizing Agents 11
2.2.4 Physical and Chemical Background to the Mechanisms of Surface-Wetting and Penetration 13
2.2.4.1 Surface Wetting 14
2.2.4.2 Liquid Penetration 15
2.2.5 Surface and Internal Sizing 17
2.2.6 Sizing Agents 18
2.2.6.1 Alkenyl Succinic Anhydride (ASA) 19
2.2.6.2 Rosin Sizes 19
2.2.6.3 Alkylketen Dimer (AKD) 23
2.2.6.4 Polymeric Sizing Agents (PSA) 26
2.2.7 Determination of the Sizing Degree (Performance Analysis) 28
2.2.7.1 Cobb Water Absorption 29
2.2.7.2 Contact Angle Measurement 30
2.2.7.3 Penetration Dynamics Analysis 31
2.2.7.4 Further Qualitative Analysis Methods 33
2.2.7.4.1 Ink Stroke 33
2.2.7.4.2 Immersion Test 33
2.2.7.4.3 Floating Test 34
2.2.7.4.4 Hercules Sizing Tester (HST) 34
2.2.8 Sizing Agent Detection (Qualitative Analysis) and Determination of the Sizing Agent Content (Quantitative Analysis) 35
2.2.8.1 Destructive Methods 35
2.2.8.2 Non Destructive Methods 36
2.3 Alkenyl Succinic Anhydride (ASA) 36
2.3.1.1 Chemical Composition and Production of ASA 37
2.3.1.2 Mechanistic Reaction Models 39
2.3.1.3 ASA Application 42
2.3.1.3.1 Emulsification 42
2.3.1.3.2 Dosing 44
2.3.1.4 Mechanistic Steps of ASA Sizing 46
2.3.2 Physico-Chemical Aspects during ASA Sizing 48
2.3.2.1 Reaction Plausibility 48
2.3.2.1.1 Educt-Product Balance / Kinetics 48
2.3.2.1.2 Energetics 51
2.3.2.1.3 Sterics 52
2.3.2.2 Phenomena based on Sizing Agent Mobility 53
2.3.2.2.1 Sizing Agent Orientation 54
2.3.2.2.2 Intra-Molecular Orientation 55
2.3.2.2.3 Sizing Agent Agglomeration 55
2.3.2.2.4 Fugitive Sizing / Sizing Loss / Size Reversion 56
2.3.2.2.5 Sizing Agent Migration 58
2.3.2.2.6 Sizing Reactivation / Sizing Agent Reorientation 59
2.3.3 Causes for Interactions during ASA Sizing 60
2.3.3.1 Process Parameters 61
2.3.3.1.1 Temperature 61
2.3.3.1.2 pH-Value 62
2.3.3.1.3 Water Hardness 63
2.3.3.2 Fiber Types 64
2.3.3.3 Filler Types 65
2.3.3.4 Cationic Additives 66
2.3.3.5 Anionic Additives 67
2.3.3.6 Surface-Active Additives 68
2.4 Limitations of State-of-the-Art ASA-Sizing Analysis 69
2.5 Optical ASA Localization 71
2.5.1 General Background 71
2.5.2 Confocal Microscopy 72
2.5.2.1 Principle 72
2.5.2.2 Features, Advantage and Applicability for Paper-Component Analysis 74
2.5.3 Dying / Staining 75
3 Discussion of Results 77
3.1 Localization of ASA within the Sheet Structure 77
3.1.1 Choice of Dyes 77
3.1.1.1 Dye Type 78
3.1.1.2 Evaluation of Dye/ASA Mixtures 80
3.1.1.2.1 Maximum Soluble Dye Concentration 80
3.1.1.2.2 Thin Layer Chromatography 81
3.1.1.2.3 FTIR-Spectroscopy 82
3.1.1.3 Evaluation of the D-ASA Emulsion 84
3.1.1.4 Paper Chromatography with D-ASA & F-ASA Emulsions 85
3.1.1.5 Evaluation of the D-ASA Emulsion’s Sizing Efficiency 86
3.1.2 The Localization Method 87
3.1.2.1 The Correlation between ASA Distribution and Agglomeration 88
3.1.2.2 Measurement Settings 89
3.1.2.3 Manual Analysis 90
3.1.2.4 Automated Analysis 92
3.1.2.4.1 Automated Localization / Microscopy Measurement 92
3.1.2.4.2 Automated Analysis / Image-Processing 93
3.1.2.5 Result Interpretation and Example Results 96
3.1.2.6 Reproducibility 97
3.1.2.7 Sample Mapping 98
3.1.3 Approaches to Localization-Method Validation 102
3.1.3.1 Raman Spectroscopy 102
3.1.3.2 Confocal Laser Scanning Fluorescent Microscopy 102
3.1.3.3 Decolorization 103
3.2 Factors Impacting the Sizing Behavior of ASA 104
3.2.1 ASA Type 105
3.2.2 Emulsion Parameters 107
3.2.2.1 Hydrolyzed ASA Content 107
3.2.2.2 ASA/Starch Ratio 109
3.2.2.3 Emulsion Age 110
3.2.3 Stock Parameters 111
3.2.3.1 Long Fiber/Short Fiber Ratio 111
3.2.3.2 Furnish Type 112
3.2.3.3 Degree of Refining 114
3.2.3.4 Filler Type/Content 116
3.2.4 Process Parameters 119
3.2.4.1 Temperature 119
3.2.4.2 pH-Value 120
3.2.4.3 Conductivity 122
3.2.4.4 Water Hardness 123
3.2.4.5 Shear Rate 125
3.2.4.6 Dwell Time 127
3.2.4.7 Dosing Position & Dosing Order 128
3.2.4.8 Drying 130
3.2.4.9 Aging 131
3.3 Factors Impacting the Localization Behavior of ASA 132
3.3.1 Degree of Refining 132
3.3.2 Sheet Forming Conductivity 135
3.3.3 Water Hardness 136
3.3.4 Retention Aid (PAM) 137
3.3.5 Contact Curing 138
3.3.6 Accelerated Aging 139
3.4 Main Optimization Approach 141
3.4.1 Optimization of ASA Sizing Performance Characteristics 142
3.4.2 Emulsion Modification 144
3.4.2.1 Lab Trials / RDA Sheet Forming 146
3.4.2.2 TPM Trials 147
3.4.2.3 Industrial-Scale Trials 149
3.4.2.4 Correlation between Sizing Performance Optimization and Agglomeration Behavior on the Example of PAAE 152
3.5 Holistic Approach to Sizing Performance Explanation 154
4 Experimental Approach 157
4.1 Characterization of Methods, Measurements and Chemicals used for the Optical Localization-Analysis of ASA 157
4.1.1 Characterization of used Chemicals 157
4.1.1.1 Preparation of Dyed-ASA Solutions 157
4.1.1.2 Thin Layer Chromatography 157
4.1.1.3 Fourier Transformed Infrared Spectroscopy 157
4.1.1.4 Emulsification of ASA 158
4.1.1.5 Paper Chromatography 159
4.1.1.6 Particle Size Measurement 159
4.1.2 Optical Analysis of ASA Agglomerates 160
4.1.2.1 Microscopy 160
4.1.2.2 Automated Analysis 163
4.1.2.2.1 Adobe Photoshop 163
4.1.2.2.2 Adobe Illustrator 164
4.1.2.3 Confocal Laser Scanning Fluorescent Microscopy 166
4.2 Characterization of Used Standard Methods and Measurements 166
4.2.1 Stock and Paper Properties 166
4.2.1.1 Stock pH, Conductivity and Temperature Measurement 166
4.2.1.2 Dry Content / Consistency Measurement 167
4.2.1.3 Drainability (Schopper-Riegler) Measurement 167
4.2.1.4 Base Weight Measurement 168
4.2.1.5 Ultrasonic Penetration Measurement 168
4.2.1.6 Contact Angle Measurement 169
4.2.1.1 Cobb Measurement 169
4.2.1.2 Air Permeability Measurements 170
4.2.1.3 Tensile Strength Measurements 170
4.2.2 Preparation of Sample Sheets 171
4.2.2.1 Stock Preparation 171
4.2.2.2 Laboratory Refining (Valley Beater) 171
4.2.2.3 RDA Sheet Forming 171
4.2.2.4 Additive Dosing 173
4.2.2.5 Contact Curing 174
4.2.2.6 Hot Air Curing 174
4.2.2.7 Sample Aging 174
4.2.2.8 Preparation of Hydrolyzed ASA 175
4.2.2.9 Trial Paper Machine 175
4.2.2.10 Industrial-Scale Board Machine 177
4.3 Characterization of used Materials 178
4.3.1 Fibers 178
4.3.1.1 Reference Stock System 178
4.3.1.2 OCC Fibers 179
4.3.1.3 DIP Fibers 179
4.3.2 Fillers 180
4.3.3 Chemical Additives 180
4.3.3.1 ASA 180
4.3.3.2 Starches 181
4.3.3.3 Retention Aids 181
4.3.3.4 Poly Aluminum Compounds 181
4.3.3.5 Wet Strength Resin 181
4.3.4 Characterization of used Additives 182
4.3.4.1 Solids Content 182
4.4 Description of Implemented Advanced Data Analysis- and Visualization Methods 183
4.4.1 Design of Experiments (DOE183
4.4.2 Contour Plots 184
4.4.3 Box-Whisker Graphs 185
5 Conclusion 186
6 Outlook for Further Work 191
7 Bibliography 192
Appendix 207
7.1 Localization Method Reproducibility 207
7.2 DOE - Coefficient Lists 208
7.2.1 Trial 3.3.4 – Impact of Retention Aid (PAM) on Agglomeration Behavior and Sizing Performance 208
7.2.2 Trial 3.3.5 – Impact of Contact Curing on Agglomeration Behavior and Sizing Performance 208
7.2.3 Trial 3.3.6 – Impact of Accelerated Aging on Agglomeration Behavior and Sizing Performance 209
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