No description available.

[ES] Este trabajo de investigación tiene como objetivo general el desarrollo de formulaciones sostenibles a base de ácido poliláctico (PLA) mediante la incorporación de resinas naturales, resina de colofonia y derivados de resina de colofonia como agentes modificadores. La génesis de la presente tesis doctoral parte del interés de evaluar el efecto de los derivados de colofonia en las propiedades del PLA, tras observar los efectos positivos generados por estos aditivos en polímeros biodegradables de almidón termoplástico (TPS). Al tener como punto de partida los efectos positivos de los derivados de colofonia en el TPS, sería fácil continua la evaluación de los mismos aditivos en el PLA. Sin embargo, como secuencia razonable se comenzó por analizar los efectos de la propia resina de colofonia, y un derivado simple, continuando posteriormente con el análisis de derivados más complejas. Para finalizar con el análisis de derivados de colofonia en las propiedades del PLA, se utilizó un derivado experimental con el doble de complejidad. Este es derivado de colofonia con aducto de anhídrido maleico. A diferencia de la resina de colofonia, los derivados de colofonia presentan mayor estabilidad térmica y mayor estabilidad frente a la oxidación al aire libre. La evaluación de los efectos de la resina de colofonia y sus derivados en las propiedades del PLA se realizaron en cuatro estudios, compilados a su vez en tres grupos. Como epilogo de la investigación, se evaluó la posibilidad de incorporar la resina natural de la flor de Clusia rosea al ácido polilactico. Esta flor es conocida como Copey o mamey silvestre, la cual es una planta endémica del caribe. La evaluación del efecto de esta resina en el PLA se realizó como estudio número cinco, dando lugar a un último grupo, número cuatro. ¿ Grupo 1, uso de resinas de colofonia y un derivado común (ambos de bajo peso molecular). o Primer estudio ¿ Grupo 2, uso de dos derivados de colofonia (de alto peso molecular). o Segundo estudio ¿ Grupo 3, uso de derivado de colofonia con aducto de anhídrido maleico. o Tercer estudio o Cuarto estudio ¿ Grupo 4, evaluación de resina natural de flor de Clusia rosea. o Quinto estudio El procesado de los materiales se realizó por incorporación directa de los derivados de colofonia, mediante extrusión fundido. A continuación, las mezclas extruidas fueron trituradas en forma de granza o pellet, para posteriormente producir probetas normalizadas de ensayo mediante inyección por moldeo, las cuales se utilizaron en la caracterización. / [CA] Aquest treball de recerca té com a objectiu general el desenvolupament de formulacions sostenibles a base d'àcid polilàctic (PLA) mitjançant la incorporació de resines naturals, resina de colofònia i derivats de resina de colofònia com a agents modificadors. La gènesi de la present tesi doctoral part de l'interés d'avaluar l'efecte dels derivats de colofònia en les propietats de l'àcid polilàctic, després d'observar els efectes positius generats per aquestos additius en polímers biodegradables de midó termoplàstic (TPS). En tindre com a punt de partida els efectes positius dels derivats de colofònia en el TPS, seria fàcil continuar l'avaluació dels mateixos additius en el PLA. No obstant això, com a seqüència raonable es va començar per analitzar els efectes de la pròpia resina de colofònia, i un derivat simple, continuant posteriorment amb l'anàlisi de derivats més complexos. Per a finalitzar amb l'anàlisi dels derivats de colofònia en les propietats del PLA, es va utilitzar un derivat experimental amb el doble de complexitat. Aquest és derivat de colofònia amb adducte d'anhídrid maleic. A diferència de la resina de colofònia, els derivats de colofònia presenten major estabilitat tèrmica i major estabilitat enfront de l'oxidació a l'aire lliure. L'avaluació dels efectes de la resina de colofònia i els seus derivats en les propietats del PLA es van realitzar en quatre estudis, compilats al seu torn en tres grups. Com epilogue de la investigació, es va avaluar la possibilitat d'incorporar la resina natural de la flor de Clusia rosea a l'àcid polilàctic. Aquesta flor és coneguda com Copey o mamey silvestre, la qual és una planta endèmica del caribe. L'avaluació de l'efecte d'aquesta resina en el PLA es va realitzar com a estudi número cinc, donant lloc a un últim grup, número quatre. ¿ Grup 1, ús de resines de colofònia i un derivat comú (tots dos de baix pes molecular). o Primer estudi ¿ Grup 2, ús de dos derivats de colofònia (d'alt pes molecular). o Segon estudi ¿ Grup 3, ús de derivat de colofònia amb adducte d'anhídrid maleic. o Tercer estudi o Quart estudi ¿ Grup 4, avaluació de resina natural de flor de Clusia rosea. o Cinqué estudi El processament dels materials es va realitzar per incorporació directa dels derivats de colofònia, mitjançant extrusió. A continuació, les mescles extruides van ser triturades en forma de gransa o pèl·let, per a posteriorment produir provetes normalitzades d'assaig mitjançant injecció per emotlament, les quals es van utilitzar en la caracterització. / [EN] This research aims to develop sustainable formulations based on polylactic acid (PLA) by incorporating natural resin, rosin resin, and rosin resin derivatives as modifying agents. The genesis of this doctoral thesis is based on the interest in evaluating the effect of rosin resin derivatives on the properties of polylactic acid after observing the positive results generated by these additives in biodegradable polymers of thermoplastic starch (TPS). Having as a starting point the positive effects of rosin resin derivatives in TPS, it would be easy to continue evaluating the same additives in PLA. However, as a proper sequence, the evaluations were initiated by analyzing the effects of the rosin resin and a simple derivative, then continuing to investigate more complex derivatives. To finish with the analysis of rosin resin derivatives in the properties of PLA, an experimental rosin resin derivative with twice the complexity was used. This is a rosin resin derivative with maleic anhydride adduct. Unlike rosin resin, rosin resin derivatives exhibit higher thermal and oxidation stability. The effects evaluation of rosin resin and its derivatives in the properties of PLA were carried out in four studies. They were compiled into three groups. As an epilogue to this research, the possibility of incorporating the natural resin of the Clusia rosea flower into polylactic acid was evaluated. This flower is called Copey or wild mamey, an endemic plant native to the Caribbean. This resin effect in the PLA was evaluated as study number five, giving rise to the last group, number four. ¿ Group 1, use of rosin resin and a common derivative (both of low molecular weight). ¿ First study ¿ Group 2, use of two rosin resin esters (high molecular weight). ¿ Second study ¿ Group 3, use of rosin reisn derivative with maleic anhydride adduct. ¿ Their study ¿ Fourth study Group 4, evaluation of the natural resin from the Clusia rosea flower. ¿ Fith study The material was processed by directly incorporating the rosin resin derivatives by melt extrusion. Subsequently, the extruded mixtures were crushed as pellet to produce normalized testing samples through injection molding. These testing samples were then used in the characterization. / Gracias a la Universitat Politècnica de València y al grupo de investigación DEMES por el apoyo a través del contrato predoctoral para la formación de personal investigador financiado por la estructura de investigación de la UPV – subprograma 2 (FPI-2018-S2-31946). Al Programa de Movilidad para estudiantes de doctorado de la Universitat Politècnica de València por la ayuda para “Estancias en Centros Extranjeros de Prestigio”. / Rosa Ramírez, HDL. (2023). Desarrollo de formulaciones de ácido poliláctico (PLA) basadas en la incorporación de derivados de la colofonia [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/194754

[ES] La Tesis Doctoral investigó el uso de la resina de pino (colofonia o gum rosin, GR) y sus derivados modificados químicamente, como aditivos sostenibles de biopolímeros basados en almidón termoplástico. El trabajo se dividió en seis secciones de investigación. Dos trabajos previos y cuatro trabajos medulares, cada uno de los cuales constituyeron los objetivos específicos de la investigación. Los trabajos previos permitieron determinar que la resina de pino y derivados pueden ser utilizados tanto en matrices poliméricas sintéticas (policloruro de vinilo, PVC), como en matrices poliméricas biodegradables (una mezcla de poliácido láctico y poli(butilén adipato co-tereftalato - PLA/PBAT). En el caso del PVC, se estudió el efecto de un derivado de colofonia, el trietilén glicol de colofonia (TEGR), como aditivo natural para incrementar la viscosidad en plastisoles basados en PVC. En el caso de estudio con una matriz biodegradable, se usó colofonia sin modificar (GR), como agente de control de tamaño de dominios de PBAT para aumentar la tenacidad de formulaciones basadas en una mezcla de PLA/PBAT. Luego, se estudió el uso de la resina de pino y derivados como aditivos de biopolímeros basados en almidón termoplástico (TPS) y el efecto de las resinas en las diferentes formulaciones de estos materiales. En primera instancia se estudiaron y establecieron las condiciones de procesamiento para obtener un almidón totalmente plastificado (almidón termoplástico - TPS) utilizando mezclas de almidón de maíz plastificado con glicerol y agua; procesadas a diferentes perfiles de temperatura de extrusión. En una siguiente instancia, se estudiaron mezclas de TPS con cinco derivados de resina de colofonia: colofonia sin modificar (GR), colofonia deshidrogenada (RD), colofonia modificada con anhidrido maleico (CM) y dos ésteres de colofonia, un pentaeritritol éster (LF) y un éster de glicerol grado alimenticio (UG). A continuación, se estudió el comportamiento de un material de interés comercial al ser aditivado con derivados de la resina de pino. Para ello, se usó colofonia sin modificar (GR) y dos ésteres de pentaeritritol de colofonia (LF, y UT). La matriz de estudio fue un biopolímero del tipo Mater-Bi (Mater-Bi® NF 866 (Mater-Bi), una mezcla comercial basada en almidón termoplástico (TPS), un poliéster alifático-aromático (polibutilén adipato co-tereftalato) (PBAT) y poly-(ε)-caprolactona (PCL)). Finalmente, se estudiaron los materiales formulados con el material de interés comercial (Mater-Bi) y las resinas y derivados seleccionados (GR, LF y UT) desde un punto de vista microscópico, para determinar a profundidad las interacciones de los componentes del Mater-Bi con cada una de las resinas. Los resultados obtenidos se muestran favorables y prometedores pues demuestran que las resinas de pino y sus derivados son una alternativa viable para ser usados como aditivos naturales en una diversidad de materiales, tanto sintéticos como biobasados y biodegradables. Además, las resinas de pino y colofonia son materiales sostenibles que proviene de fuentes 100% naturales y renovables, por lo que su uso supone una disminución del impacto en el medio ambiente. / [CA] La Tesi Doctoral va investigar l'ús de la resina de pi (colofònia o gum rosin, GR) i els seus derivats modificats químicament, com a additius sostenibles de biopolímers basats en midó termoplàstic. El treball es va dividir en sis seccions d'investigació. Dos treballs previs i quatre treballs medul·lars, cadascun dels quals van constituir els objectius específics de la investigació. Els treballs previs van permetre determinar que la resina de pi i derivats poden ser utilitzats tant en matrius polimèriques sintètiques (policlorur de vinil, PVC), com en matrius polimèriques biodegradables (una mescla de poliácido làctic i poli(butilén adipat co-tereftalato - PLA/PBAT). En el cas del PVC, es va estudiar l'efecte d'un derivat de colofònia, el trietilén glicol de colofònia (TEGR), com a additiu natural per a incrementar la viscositat en plastisoles basats en PVC. En el cas d'estudi amb una matriu biodegradable, es va usar colofònia sense modificar (GR), com a agent de control de grandària de dominis de PBAT per a augmentar la tenacitat de formulacions basades en una mescla de PLA/PBAT. Després, es va estudiar l'ús de la resina de pi i derivats com a additius de biopolímers basats en midó termoplàstic (TPS) i l'efecte de les resines en les diferents formulacions d'aquests materials. En primera instància es van estudiar i van establir les condicions de processament per a obtindre un midó totalment plastificat (midó termoplàstic - TPS) utilitzant mescles de midó de dacsa plastificada amb glicerol i aigua; processades a diferents perfils de temperatura d'extrusió. En una següent instància, es van estudiar mescles de TPS amb cinc derivats de resina de colofònia: colofònia sense modificar (GR), colofònia deshidrogenada (RD), colofònia modificada amb anhidrido maleic (CM) i dos èsters de colofònia, un pentaeritritol èster (LF) i un èster de glicerol grau alimentós (UG). A continuació, es va estudiar el comportament d'un materials d'interés comercial en ser aditivado amb derivats de la resina de pi. Per a això, es va usar colofònia sense modificar (GR) i dos èsters de pentaeritritol de colofònia (LF, i UT). La matriu d'estudi va ser un biopolímer del tipus Mater-Bi (Mater-Bi® NF 866 (Mater-Bi), una mescla comercial basada en midó termoplàstic (TPS), un polièster alifàtic-aromàtic (polibutilén adipat co-tereftalato) (PBAT) i poly-(ε)-caprolactona (PCL)). Finalment, es van estudiar els materials formulats d'interés comercial (Mater-Bi) i les resines i derivats seleccionats (GR, LF i UT) des d'un punt de vista microscòpic, per a determinar a profunditat les interaccions dels components del Mater-Bi amb cadascuna de les resines. Els resultats obtinguts es mostren favorables i prometedors perquè demostren que les resines de pi i els seus derivats són una alternativa viable per a ser usats com a additius naturals en una diversitat de materials, tant sintètics com biobasados i biodegradables. A més, les resines de pi i colofònia són materials sostenibles que prové de fonts 100% naturals i renovables, per la qual cosa el seu ús suposa una disminució de l'impacte en el medi ambient. / [EN] The Doctoral Thesis investigated the use of pine resin (colophony or gum rosin, GR) and its chemically modified derivatives, as sustainable additives for biopolymers based on thermoplastic starch (TPS). The work was divided into six research sections. Two previous studies and four core studies, each of which constituted the specific objectives of the research. Previous studies made it possible to determine that gum rosin and derivatives can be used both in synthetic polymeric matrices (polyvinyl chloride, PVC) and in biodegradable polymeric matrices (a blend of polyacid lactic acid and poly (butylene adipate co-terephthalate - PLA/PBAT). In the case of PVC, the effect of a rosin derivative, triethylene glycol ester of gum rosin (TEGR), was studied as a natural additive to increase the viscosity in PVC-based plastisols. In the case of a study with a biodegradable matrix, unmodified rosin (GR) was used as a PBAT domain size control agent to increase the toughness of formulations based on a PLA/PBAT blend. Then, the use of gum rosin and derivatives as additives of biopolymers based on thermoplastic starch (TPS) and the effect of the resins in the different formulations of these materials were studied. In the first instance, the processing conditions were studied to obtain a fully plasticized starch (thermoplastic starch - TPS) using mixtures of plasticized corn starch with glycerol and water; processed at different extrusion temperature profiles. In the next instance, blends of TPS with five rosin derivatives were studied: unmodified rosin (GR), dehydrogenated rosin (RD), maleic anhydride-modified rosin (CM) and two rosin esters, a pentaerythritol ester (LF), and a food-grade glycerol ester of gum rosin (UG). Next, the behavior of a commercial interest material when added with derivatives of gum rosin was studied. Unmodified gum rosin (GR) and two pentaerythritol esters of gum rosin (LF and UT) were used. The studied matrix was a Mater-Bi type biopolymer (Mater-Bi® NF 866 (Mater-Bi), a commercial blend based on thermoplastic starch (TPS), an aliphatic-aromatic polyester (polybutylene adipate co-terephthalate) (PBAT ) and poly-(ε)-caprolactone (PCL)). Finally, the formulated materials were studied from a microscopic point of view, to determine in-depth the interactions of the components of Mater-Bi with each of the gum rosin and derivatives resins. The results obtained are favorable and promising as they show that gum rosin and its derivatives are a viable alternative to be used as natural additives in a variety of materials, both synthetic and biobased and biodegradable. In addition, gum rosin and derivatives resins are sustainable materials that come from 100% natural and renewable sources, so their use reduces their impact on the environment. / Agradezco a la Secretaría de Educación Superior, Ciencia, Tecnología e Innovación (SENESCYT) por el apoyo económico en parte de mis estudios doctorales. / Aldas Carrasco, MF. (2021). Uso de derivados de colofonia como aditivos sostenibles en biopolímeros de almidón termoplástico (TPS) [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/171770 / TESIS

<p>Edge wicking, i.e. in-plane wetting, is an important parameter for liquid packaging board products. Before filling of the products at the dairy the web is being sterilised with hydrogen peroxide (H2O2). A tube is shaped and cut into packages which mean that new surfaces are created. If a short stop occurs in the sterilising bath the raw edges exposed to H2O2 could absorb the liquid and when the package later is being filled this absorption could lead to tube burst. For the end products it is also important to prevent the liquid from penetrating the raw edges of the board in order to maintain the functionality and fresh look of the package.</p><p>To control edge wicking different kinds of internal hydrophobic sizing agents are used. Alkyl ketene dimer (AKD) is the most common size in neutral sizing and rosin in conjunction with alum is the traditional acidic sizing agent. AKD and rosin size are often used in combination (dual sizing) to make the board hydrophobic.</p><p>The objective of this work was to examine the effects of the sizing agents on different pulps in different dosages. The pulps used in the sheet preparation were unbleached kraft pulp as well as bleached and unbleached CTMP refined to different levels. Apart from varying the size dosages, the wet sheets were also pressed at different levels to vary the density. The major part of the study included dual sizing but a minor part also concerned mono sized sheets.</p><p>The parameters investigated on the laboratory sheets were STFI-Density, hydrogen peroxide edge wicking, pressurised edge wicking, lactic acid edge wicking (LA) and AKD and rosin size content.</p><p>In hydrogen peroxide edge wicking the amount of size was the central source of improved wick index. The retention was therefore of great significance for the results. The dual sized sheets were found to give least edge wicking, due to the synergy effect between AKD and alum rosin size. The kraft pulps gave sheets with satisfactory edge wicking even at the lowest size dosage (1 kg/t) while CTMP required a dosage of 4 kg/t to reach the same wick index.</p><p>To achieve acceptable pressurised edge wicking values the most important parameter was found to be the density of the sheets. The kraft pulp sheets gave the lowest edge penetration while the high freeness CTMP sheets did not give satisfactory penetration resistant even at the highest size dosage.</p><p>The edge wicking of lactic acid could be prevented by sizing with AKD only. Sheets made from mono sized sheets containing rosin size did not manage to avoid a large in-plane wetting of the board structure. Hence, dual sizing to improve the edge wicking of lactic acid is not necessary. The density was found not to be an important parameter in lactic acid edge wicking, all the pulps got equal edge wicking regardless of density. Retention above 1 kg/t AKD in sheets was enough to prevent penetration. Retention above 1.5 kg/t AKD in sheet did not improve the edge wicking any further.</p><p>No significant difference in sizeability between unbleached and bleached CTMP was observed.</p>

No description available.

No description available.

Edge wicking, i.e. in-plane wetting, is an important parameter for liquid packaging board products. Before filling of the products at the dairy the web is being sterilised with hydrogen peroxide (H2O2). A tube is shaped and cut into packages which mean that new surfaces are created. If a short stop occurs in the sterilising bath the raw edges exposed to H2O2 could absorb the liquid and when the package later is being filled this absorption could lead to tube burst. For the end products it is also important to prevent the liquid from penetrating the raw edges of the board in order to maintain the functionality and fresh look of the package. To control edge wicking different kinds of internal hydrophobic sizing agents are used. Alkyl ketene dimer (AKD) is the most common size in neutral sizing and rosin in conjunction with alum is the traditional acidic sizing agent. AKD and rosin size are often used in combination (dual sizing) to make the board hydrophobic. The objective of this work was to examine the effects of the sizing agents on different pulps in different dosages. The pulps used in the sheet preparation were unbleached kraft pulp as well as bleached and unbleached CTMP refined to different levels. Apart from varying the size dosages, the wet sheets were also pressed at different levels to vary the density. The major part of the study included dual sizing but a minor part also concerned mono sized sheets. The parameters investigated on the laboratory sheets were STFI-Density, hydrogen peroxide edge wicking, pressurised edge wicking, lactic acid edge wicking (LA) and AKD and rosin size content. In hydrogen peroxide edge wicking the amount of size was the central source of improved wick index. The retention was therefore of great significance for the results. The dual sized sheets were found to give least edge wicking, due to the synergy effect between AKD and alum rosin size. The kraft pulps gave sheets with satisfactory edge wicking even at the lowest size dosage (1 kg/t) while CTMP required a dosage of 4 kg/t to reach the same wick index. To achieve acceptable pressurised edge wicking values the most important parameter was found to be the density of the sheets. The kraft pulp sheets gave the lowest edge penetration while the high freeness CTMP sheets did not give satisfactory penetration resistant even at the highest size dosage. The edge wicking of lactic acid could be prevented by sizing with AKD only. Sheets made from mono sized sheets containing rosin size did not manage to avoid a large in-plane wetting of the board structure. Hence, dual sizing to improve the edge wicking of lactic acid is not necessary. The density was found not to be an important parameter in lactic acid edge wicking, all the pulps got equal edge wicking regardless of density. Retention above 1 kg/t AKD in sheets was enough to prevent penetration. Retention above 1.5 kg/t AKD in sheet did not improve the edge wicking any further. No significant difference in sizeability between unbleached and bleached CTMP was observed.

see document / Master of Science

The aims of the work this thesis is based upon were to develop convenient analytical procedures for determining resin acids in biological and environmental matrices, and apply them to enhance understanding of the occurrence, exposure to and uptake by exposed individuals of resin acids. Particular focus has been on the workplace environment of the Swedish wood pellets industry. Sample extraction procedures and high-performance liquid chromatography/electrospray ionisation-mass spectrometry (HPLC/ESI-MS) methodologies were developed for measuring resin acids in dust, skin and urine samples. Chromatographic separation of abietic (AA) and pimaric acid was achieved by using a polar-embedded C12 stationary phase. The HPLC/ESI-MS method avoids undesirable oxidation of AA, which was found to occur during the derivatisation step in the standard MDHS 83/2 gas chromatography/flame ionisation detection (GC/FID) methodology, leading to false observations of both AA and the oxidation product 7-oxodehydroabietic acid (7-OXO). Personal exposures to resin acids in the Swedish wood pellet production industry were found to be lower, on average, than the British Occupational Exposure Limit for rosin (50 µg/m3). The oxidised resin acid 7-OXO, was detected in both dust and skin samples indicating the presence of allergenic resin acids. A correlation between air and post-shift urinary concentrations of dehydroabietic acid (DHAA), and a trend towards an increase in urinary 7-OXO during work shifts, were also observed. Whether the increase in 7-OXO was due to direct uptake or metabolism of other resin acids cannot be concluded from the results. An efficient HPLC/UV methodology with diode-array detection was developed for screening commercial products for rosin that could be used in laboratories lacking mass spectrometers. Very high concentrations of free resin acids were detected in depilatory wax strips using the method. / At the time of doctoral defense, the following paper was unpublished and had a status as follows: Paper 4: Submitted.

No description available.