62 research outputs found
Diseño de una unidad de evaporación multiefecto para la concentración de zumo de granada
[ES] En este proyecto se ha estudiado el proceso de concentración de zumo de granada mediante evaporación. Se ha desarrollado un algoritmo en Matlab para realizar los cálculos de balances tanto de materia como de energía para evaporadores de 3, 4 y 5 efectos, y se han comparado los resultados con un evaporador de simple efecto. Para la comparación, se ha realizado un análisis de costes para determinar qué evaporador es el óptimo, resultando el evaporador de 3 efectos como el más rentable y quedando demostrado que en este proceso la evaporación en múltiple efecto es más efectiva que en simple efecto. Además, se han realizado los cálculos mecánicos y dimensionales pertinentes para el diseño del evaporador óptimo. También se ha utilizado el simulador ProMax para reproducir el proceso utilizando el evaporador óptimo, resultando la simulación exitosa y con resultados muy similares a la simulación con Matlab.[EN] In this project, the process of concentration of pomegranate juice through evaporation has been studied. An algorithm has been developed in Matlab in order to solve all mass and energy balances in evaporators of 3, 4 and 5 effects, and the results have been compared with a single effect evaporator. A cost analysis has been carried out in order to determine which evaporator is thebest, being the 3 effects evaporator the most profitable and being demonstrated that the multiple effect evaporation is more effective than single effect evaporationin this process. Moreover, mechanic and dimensional calculations have been carried out to design the optimal evaporator. Finally, ProMax simulator has been used to reproduce the process with the optimal evaporator, resulting in a successful simulation due to very similar results with the Matlab simulation.Gómez Caturla, J. (2019). Diseño de una unidad de evaporación multiefecto para la concentración de zumo de granada. http://hdl.handle.net/10251/126321TFG
Desarrollo, compatibilización y caracterización de plásticos que imitan la madera con matriz de biopolietileno y harina de cáscara de argán.
[ES] El presente estudio se ha centrado en el desarrollo de plásticos que imitan la
madera basados en micronizado de cáscara de argán (MAS) como relleno y polietileno
de alta densidad obtenido de la caña de azúcar (Bio-HDPE) como matriz, siguiendo los
principios propuestos por la economía circular, donde el objetivo es disminuir los
residuos a cero con la utilización de residuos de la industria del argán como rellenos.
Los materiales desarrollados en este trabajo se prepararon por procesos de extrusión e
inyección. Para aumentar la compatibilidad entre las partículas de cáscara de argán y la
poliolefina se utilizaron diferentes compatibilizantes y refuerzos adicionales,
concretamente polietilen-graft-maleico anhídrido (PE-g-MA 3%), aceite de linaza
maleinizado (MLO 7,5 phr), nanotubos de halloysita (HNTs 7,5 phr), y una combinación
de MLO y HNTs (3,75 phr cada uno). Se analizaron las propiedades mecánicas,
morfológicas, térmicas, termomecánicas, colorimétricas y de humectabilidad de cada
material. Los resultados mostraron que el MAS actuó como un elemento de refuerzo,
aumentando la rigidez del Bio-HDPE, y que los HNTs aumentan todavía más este efecto
reforzante. El MLO y el PE-g-MA, junto a los HNTs, mejoran la compatibilidad entre el
MAS y el Bio-HDPE, concretamente debido a los enlaces formados entre los grupos
basados en oxígeno presentes en cada compuesto. La estabilidad térmica también mejoró
como resultado de la inclusión de MAS y HNTs. En general, se obtuvieron plásticos que
imitan la madera con colores marrones rojizos, con rigidez aumentada, buena
estabilidad térmica, compatibilidad mejorada y buenas propiedades de humectabilidad.[EN] The present study reports on the development of wood plastic composites (WPC)
based on micronized argan shell (MAS) as a filler and high-density polyethylene
obtained from sugarcane (Bio-HDPE), following the principles proposed by the circular
economy in which the aim is to achieve zero waste by the introduction of residues of
argan as a filler. The blends were prepared by extrusion and injection molding processes.
In order to improve compatibility between the argan particles and the green polyolefin,
different compatibilizers and additional filler were used, namely polyethylene grafted
maleic anhydride (PE-g-MA 3 wt.-%), maleinized linseed oil (MLO 7.5 phr), halloysite
nanotubes (HNTs 7.5 phr), and a combination of MLO and HNTs (3.75 phr each). The
mechanical, morphological, thermal, thermomechanical, colorimetric, and wettability
properties of each blend were analyzed. The results show that MAS acts as a reinforcing
filler, increasing the stiffness of the Bio-HDPE, and that HNTs further increases this
reinforcing effect. MLO and PE-g-MA, altogether with HNTs, improve the compatibility
between MAS and Bio-HDPE, particularly due to bonds formed between oxygen-based
groups present in each compound. Thermal stability was also improved provided by the
addition of MAS and HNTs. All in all, reddish-like brown wood plastic composites with
improved stiffness, good thermal stability, enhanced compatibility, and good wettability
properties were obtained.[CA] El present estudi es centra en el desenvolupament de plàstics que imiten la fusta
basats en micronitzat de corfa d’argània (MAS) com a reforç y polietilé d’alta densitat
obtés de la canya de sucre (Bio-HDPE) com a matriu, seguint els principis de l’economía
circular, on l’objectiu es reduïr els residus a zero mitjançant l’utilització de residus de
l’industria de l’argània. Els materials desenvolupats en aquest treball es van preparar
per processos d’extrussió e injecció. Per tal d’augmentar la compatibilitat entre les
partícules de corfa d’argània i la poliolefina es van utilizar diferents compatibilitzants y
reforços adicionals, més concretamente polietilen-graft-maleic anhídrid (PE-g-MA 3%),
oli de llinosa maleinitzat (MLO 7,5 phr), nanotubs d’halloysita (HNTs 7,5 phr), y una
combinación de MLO i HNTs (3,75 phr cadascun). Es van analizar les propietats
mecàniques, morfològiques, tèrmiques, termomecàniques, colorimètriques i
d’humectabilitat de cada material. Els resultats van mostrar que el MAS va actuar com
un element de reforç, augmentant la rigidesa del Bio-HDPE, y que els HNTs
augmentaven encara més aquest efecte reforçant. El MLO i el PE-g-MA, juntament amb
els HNTs, van millorar la compatibilitat entre el MAS i el Bio-HDPE, degut als enllaços
formats entre els grups basats en oxígen de cada compost. L’estabilitat tèrmica també
va millorar com a resultat de la incorporació de MAS i HNTs. En general, es van obtener
plàstics que imiten la fusta amb color marró vermellós, amb rigidesa augmentada, bona
estabilitat térmica, compatibilitat millorada i bones propietats d’humectabilitat.Gómez Caturla, J. (2021). Desarrollo, compatibilización y caracterización de plásticos que imitan la madera con matriz de biopolietileno y harina de cáscara de argán. Universitat Politècnica de València. http://hdl.handle.net/10251/173748TFG
Desarrollo y caracterización de polímeros de alto rendimiento medioambiental derivados de residuos agroindustriales y aditivos de origen renovable
Tesis por compendio[ES] La presente tesis doctoral tiene como principal objetivo el desarrollo de materiales poliméricos que sean respetuosos con el medio ambiente y favorezcan modelos de economía circular, centrando las líneas de investigación en el reaprovechamiento de residuos de la industria del mango y en la utilización de ácido poliláctico (PLA) como principal matriz polimérica. Para ello se emplean diferentes técnicas de procesado como el electrospinning, la extrusión, la inyección o la producción de films por disolución. Además, se plantea la utilización de diferentes aditivos como plastificantes y cargas lignocelulósicas de origen renovable para mejorar las propiedades de estos materiales sin comprometer su alto potencial medioambiental.
El primer bloque de la tesis centra sus esfuerzos en el reaprovechamiento de diferentes residuos del mango (uno de los cultivos más populares del mundo), como la piel y el kernel, para desarrollar diferentes materiales con un gran contenido natural. Dentro de los estudios realizados en este bloque se incluye la extracción de almidón a partir del kernel de mango para la posterior fabricación de nanofibras por electrospinning, con gran aplicación en el sector médico. Otros estudios realizados proponen la combinación de matrices poliméricas como el biopolipropileno y el PLA, en combinación con harina de piel de mango y harina de hueso de mango, respectivamente, mediante procesos de extrusión, extrusión reactiva (REX) e inyección. En el caso del biopolipropileno se utilizan además agentes compatibilizantes basados en ácido itacónico para aumentar la adhesión entre las partículas lignocelulósicas de la piel del mango con la matriz polimérica, la cual es altamente apolar. Por otro lado, a las formulaciones de PLA y harina de hueso de mango se le añaden plastificantes como la triacetina y la tributirina para aumentar las propiedades dúctiles del PLA. Un cuarto estudio se enfoca en la producción de films de glicerol con harina de hueso de mango, rica en almidón, para observar cómo afecta el tamaño de partícula de la harina sobre las propiedades de los films. Por último, se propone el desarrollo de materiales termoplásticos ricos en almidón utilizando harina de kernel de mango en combinación con diferentes plastificantes como glicerol, sorbitol y urea. Estos materiales ricos en almidón son procesados por extrusión e inyección y son completamente biodegradables y de origen natural.
El segundo y último bloque de la tesis está enfocado a la utilización del ácido poliláctico obtenido de fuentes renovables en procesos de extrusión e inyección. Este poliéster es un polímero biodegradable cuya principal desventaja es su gran fragilidad. Por ello, se han empleado diferentes tipos de plastificantes naturales para incrementar las propiedades dúctiles del PLA. En un primer trabajo, se combina el PLA con α-terpinil acetato, un plastificante de origen renovable. Además, se añade piel de mandarina molida como carga natural para evaluar si este plastificante es capaz de aumentar la ductilidad de mezclas de PLA con cargas lignocelulósicas, obtenido resultados muy positivos. Un segundo trabajo plantea la combinación de PLA con dietil-L-tartrato, un plastificante obtenido del ácido tartárico, encontrado en la uva y el tamarindo, obteniendo elongaciones de más de un 300%. Por último, dos estudios más plantean la combinación de PLA con terpenoides, más concretamente ésteres de geranilo y linalilo. En este sentido, uno de los trabajos se centra en variar la proporción de acetato de linalilo y acetato de geranilo en las composiciones, mientras que el otro trabajo evalúa como afecta la longitud de cadena de los ésteres de geranilo a la plastificación del PLA. Todos los plastificantes utilizados en este bloque ofrecieron resultados muy prometedores, con alargamientos a la rotura superiores al 200% en materiales completamente naturales y biodegradables con gran aplicación en el sector alimentario y del envase y embalaje.[CA] La present tesi doctoral té com a principal objectiu el desenvolupament de materials polimèrics que siguen respectuosos amb el medi ambient i afavorisquen models d'economia circular, centrant les línies d'investigació en el reaprofitament de residus de la indústria del mango i en la utilització d'àcid polilàctic (PLA) com a principal matriu polimèrica. Per a això s'empren diferents tècniques de processament com l'electrospinning, l'extrusió, la injecció o la producció de films per dissolució. A més, es planteja la utilització de diferents additius com a plastificants i càrregues lignocelulòsiques d'origen renovable per a millorar les propietats d'aquests materials sense comprometre el seu alt potencial mediambiental.
El primer bloc de la tesi centra els seus esforços en el reaprofitament de diferents residus del mango (un dels cultius més populars del món), com la pell i el kernel, per a desenvolupar diferents materials amb un gran contingut natural. Dins dels estudis realitzats en aquest bloc s'inclou l'extracció de midó a partir del kernel de mango per a la posterior fabricació de nanofibers per electrospinning, amb gran aplicació en el sector mèdic. Altres estudis realitzats proposen la combinació de matrius polimèriques com el biopolipropilè i el PLA, en combinació amb farina de pell de mango i farina d'os de mango, respectivament, mitjançant processos d'extrusió, extrusió reactiva (REX) i injecció. En el cas del biopolipropilè s'utilitzen a més agents compatibilitzants basats en àcid itacònic per a augmentar l'adhesió entre les partícules lignocelulòsiques de la pell del mango amb la matriu polimèrica, la qual és altament apolar. D'altra banda, a les formulacions de PLA i farina d'os de mango se li afigen plastificants com la triacetina i la tributirina per a augmentar les propietats dúctils del PLA. Un quart estudi s'enfoca en la producció de films de glicerol amb farina d'os de mango, rica en midó, per a observar com afecta la grandària de partícula de la farina sobre les propietats dels films. Finalment, es proposa el desenvolupament de materials termoplàstics rics en midó utilitzant farina de kernel de mango en combinació amb diferents plastificants com glicerol, sorbitol i urea. Aquests materials rics en midó són processats per extrusió i injecció i són completament biodegradables i d'origen natural.
El segon i últim bloc de la tesi està enfocat a la utilització de l'àcid polilàctic obtingut de fonts renovables en processos d'extrusió i injecció. Aquest polièster és un polímer biodegradable el principal desavantatge del qual és la seua gran fragilitat. Per això, s'han emprat diferents tipus de plastificants naturals per a incrementar les propietats dúctils del PLA. En un primer treball, es combina el PLA amb α-terpinil acetat, un plastificant d'origen renovable. A més, s'afig pell de mandarina molta com a càrrega natural per a avaluar si aquest plastificant és capaç d'augmentar la ductilitat de mescles de PLA amb càrregues lignocelulòsiques, obtenint resultats molt positius. Un segon treball planteja la combinació de PLA amb dietil-L-tartrat, un plastificant obtingut de l'àcid tartàric, trobat en el raïm i el tamarinde, obtenint elongacions de més d'un 300%. Finalment, dos estudis més plantegen la combinació de PLA amb terpenoids, més concretament èsters de geranil i linalil. En aquest sentit, un dels treballs se centra en variar la proporció d'acetat de linalil i acetat de geranil en les composicions, mentre que l'altre treball avalua com afecta la longitud de cadena dels èsters de geranil a la plastificació del PLA. Tots els plastificants utilitzats en aquest bloc van oferir resultats molt prometedors, amb allargaments al trencament superiors al 200% en materials completament naturals i biodegradables amb gran aplicació en el sector alimentari i de l'envàs i embalatge.[EN] The present doctoral thesis has as its main objective the development of polymeric materials that are environmentally friendly and promote circular economy models, focusing research on the reuse of waste from the mango industry and the use of polylactic acid (PLA) as the main polymer matrix. Various processing techniques such as electrospinning, extrusion, injection, or cast film are employed for this purpose. In addition, the use of different additives such as plasticizers and lignocellulosic fillers of renewable origin is proposed to improve the properties of these materials without compromising their high environmental potential.
The first part of the thesis focuses on the reuse of various mango waste products (one of the most popular crops in the world), such as peel and kernel, to develop different materials with a high natural content. Studies in this section include the extraction of starch from mango kernels for the subsequent production of nanofibers by electrospinning, which have significant applications in the medical sector. Other studies propose the combination of polymeric matrices such as biopolypropylene and PLA, in combination with mango peel flour and mango kernel flour, respectively, through extrusion, reactive extrusion (REX), and injection processes. In the case of biopolypropylene, compatibilizing agents based on itaconic acid are also used to increase the adhesion between lignocellulosic particles from mango peel and the highly apolar polymer matrix. On the other hand, PLA formulations with mango kernel flour are supplemented with plasticizers such as triacetin and tributyrin to enhance the ductile properties of PLA. A fourth study focuses on the production of glycerol films with mango kernel flour, rich in starch, to observe how the particle size of the flour affects the film properties. Finally, the development of starch-rich thermoplastic materials is proposed using mango kernel flour in combination with different plasticizers such as glycerol, sorbitol, and urea. These starch-rich materials are processed by extrusion and injection and are completely biodegradable and of natural origin.
The second and final part of the thesis is focused on the use of polylactic acid obtained from renewable sources in extrusion and injection processes. This biodegradable polyester has the main disadvantage of being very brittle. Therefore, different types of natural plasticizers have been used to increase the ductile properties of PLA. In the first study, PLA is combined with α-terpinyl acetate, a renewable plasticizer. In addition, ground tangerine peel is added as a natural filler to evaluate if this plasticizer can increase the ductility of PLA blends with lignocellulosic fillers, yielding very positive results. A second study proposes the combination of PLA with diethyl-L-tartrate, a plasticizer obtained from tartaric acid, found in grapes and tamarind, resulting in elongations of more than 300%. Finally, two more studies propose the combination of PLA with terpenoids, specifically geranyl and linalyl esters. In this regard, one of the works focuses on varying the proportion of linalyl acetate and geranyl acetate in the compositions, while the other study evaluates how the chain length of geranyl esters affects PLA plasticization. All the plasticizers used in this section offered very promising results, with elongations at break exceeding 200% in completely natural and biodegradable materials with significant applications in the food and packaging sectors.This research is a part of the grant PID2020-116496RB-C22, funded by
MCIN/AEI/10.13039/501100011033 and the grant TED2021-131762A-I00, funded by
MCIN/AEI/10.13039/501100011033 and by the European Union
“NextGenerationEU”/PRTR. Authors also thank Generalitat Valenciana-GVA for
funding this research through the grant numbers AICO/2021/025 and CIGE/2021/094.
Funded with Aid for First Research Projects (PAID-06-22), Vice-rectorate for Research of
the Universitat Politècnica de València (UPV). J. I.-M. wants to thank FPU19/01759 grant
funded by MCIN/AEI/10.13039/501100011033 and by ESF Investing in your future. J.
G.-C. wants to thank FPU20/01732 grant funded by MCIN/AEI/10.13039/
501100011033 and by ESF Investing in your future.Gómez Caturla, J. (2024). Desarrollo y caracterización de polímeros de alto rendimiento medioambiental derivados de residuos agroindustriales y aditivos de origen renovable [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/203217Compendi
The Potential of an Itaconic Acid Diester as EnvironmentallyFriendly Plasticizer for Injection-Molded Polylactide Parts
[EN] This work reports on the use of dibutyl itaconate (DBI) as an environmentallyfriendly plasticizer for polylactide (PLA) with different proportions of DBI inthe 2.5¿20 wt% (weight content) range. A co-rotating twin-screw extrusionprocess followed by injection molding is employed for the manufacturing ofthe samples. The results show that the plasticized PLA formulation with10 wt% DBI offers the most balanced overall properties, with a noticeableincrease in the elongation at break from 4.6% (neat PLA) up to 322%, with atensile modulus of 1572 MPa, and a tensile strength of 23.8 MPa. In the caseof 15 and 20 wt% DBI formulations, PLA reaches the saturation point with nomore increase in the elongation at break and a clear decrease in the tensilemodulus. DBI also decreases the glass transition temperature (Tg)from61.3°C (neat PLA) down to 23.4°C for plasticized PLA formulation containing20 wt% DBI, thus showing the high plasticization efficiency of DBI.J.I.-M. wants to thank FPU19/01759 grant funded by MCIN/AEI/10.13039/501100011033 and by ESF Investing in your future. J.G.-C. wants to thank Generalitat Valenciana-GVA, for his FPI grant (ACIF/2021/185) and grant FPU20/01732 funded by MCIN/AEI/10.13039/501100011033 and by ESF Investing in your future. Also, Microscopy Services at UPV are also acknowledged by their help in collecting and analyzing images. This research is a part of the grant PID2020-116496RB-C22 funded by MCIN/AEI/10.13039/501100011033, and the grant AICO/2021/025 funded by Generalitat Valenciana-GVAIvorra-Martínez, J.; Peydro, MA.; Gómez-Caturla, J.; Boronat, T.; Balart, R. (2022). The Potential of an Itaconic Acid Diester as EnvironmentallyFriendly Plasticizer for Injection-Molded Polylactide Parts. Macromolecular Materials and Engineering. 307(12):1-15. https://doi.org/10.1002/mame.2022003601153071
Improved Toughness of Polylactide by Binary Blends with Polycarbonate with Glycidyl and Maleic Anhydride-Based Compatibilizers
[EN] This work reports on the development of polylactide (PLA) and polycarbonate (PC) blends with different compatibilizers with enhanced toughness. Since both polymers are immiscible, two types of compatibilizers are tested: petrochemical-based copolymers Xibond 160 and Xibond 920 with maleic anhydride and epoxy groups, respectively, and natural-based compatibilizers with the same functionalities, namely maleinized linseed oil (MLO) and, epoxidized linseed oil (ELO). Mechanical, thermal, and morphological characterization shows better properties for the PLA/PC (80/20 wt%) blends with chemically modified natural oils (ELO and MLO). The addition of 5 phr (parts per hundred resin) of MLO gives the maximum values for impact strength and elongation at break. Moreover, the glass transition temperature (Tg) slightly decreases with the addition of natural compatibilizers, thus showing some plasticization effect. Petroleum-derived compatibilizers give interesting results regarding tensile strength and stiffness without plasticization. PLA/PC blends show higher thermal stability than neat PLA, regardless of the compatibilizer used, since PC is much more thermally stable than PLA. The obtained results indicate that both petroleum-based and natural-derived compatibilizers positively contribute to enhance the properties of the binary PLA/PC blends. Nevertheless, the results with MLO suggest this is an interesting biobased solution to provide increased toughness to PLA/PC blends.L.Q.-C. wants to thank Universitat Politècnica de València for his postdoctoral PAID-10-20 grant from (SP20200073). J.G.-C. wants to thank Universitat Politècnica de València for his FPI grant from (SP20200080). This
research was funded by the Ministry of Science, Innovation, and Universities (MICIU) project number MAT2017-84909-C2-2-R.Tejada-Oliveros, R.; Gómez-Caturla, J.; Sanchez-Nacher, L.; Montanes, N.; Quiles-Carrillo, L. (2021). Improved Toughness of Polylactide by Binary Blends with Polycarbonate with Glycidyl and Maleic Anhydride-Based Compatibilizers. Macromolecular Materials and Engineering. 306(12):1-11. https://doi.org/10.1002/mame.202100480S1113061
Novel compatibilizers and plasticizers developed from epoxidized and maleinized chia oil in composites based on PLA and chia seed flour
[EN] Novel compatibilizers and plasticizers derived from epoxidized chia seed oil (ECO) and maleinized chia seed oil (MCO) have been applied in composites based on poly(lactic acid) (PLA) and 15 wt% chia seed flour (CSF). Results obtained have been compared to conventional silane coupling agent, (3-glycidyloxypropyl) trimethoxysilane (GPS), and a petroleum-based compatibilizer, poly(styrene-co-glycidyl methacrylate) copolymer (Xibond, (R)). The compatibilization effect of green composites were assessed by FTIR. The addition of all four compatibilizers improved the ductile mechanical and thermal properties of the composites. The morphology analysis revealed an improvement of interfacial adhesion of the CSF particles into the PLA matrix. In particular, ECO and MCO composites showed a roughness with long filaments in their morphology which plays a crucial role in improving the ductile properties highly. The elongation at break was 10 and 8 times higher using ECO and MCO, respectively, compared to uncompatibilized composite. Moreover, the composites manufactured showed low values (<9%) in the water uptake assay and a negligible compostability delay. The use of novel compatibilizers based on modified vegetable oils could mean an interesting proposal to obtain an entirely environmentally friendly composite with a remarkable ductile property.This research work was funded by the Ministry of Science and Innovation-¿Retos de la Sociedad¿. Project references: PID2020-119142RA-I00. I. Dominguez-Candela wants to thank Universitat Politècnica de València for his FPI grant (PAID-2019-SP20190013) and Generalitat Valenciana-GVA (ACIF/2020/233). J. Gomez-Caturla wants to thank Generalitat Valenciana-GVA, for his FPI grant (ACIF/2021/185) and grant FPU20/01732 funded by MCIN/AEI/10.13039/ 501100011033.Domínguez-Candela, I.; Gómez-Caturla, J.; Cardona, SC.; Lora-García, J.; Fombuena, V. (2022). Novel compatibilizers and plasticizers developed from epoxidized and maleinized chia oil in composites based on PLA and chia seed flour. European Polymer Journal. 173(111289):1-14. https://doi.org/10.1016/j.eurpolymj.2022.11128911417311128
Development of Polylactic Acid Thermoplastic Starch Formulations Using Maleinized Hemp Oil as Biobased Plasticizer
[EN] In this study, hemp seed oil was reacted with maleic anhydride in an ene reaction to obtain maleinized hemp seed oil (MHO). The use of MHO as a plasticizer and compatibilizer has been studied for polylactic acid (PLA) and thermoplastic starch (TPS) blends (80/20, respectively). By mechanical, thermal and morphological characterizations, the addition of MHO provides a dual effect, acting as plasticizer and compatibilizer between these two partially miscible biopolymers. The addition of MHO up to 7.5 phr (parts by weight of MHO per hundred parts of PLA and TPS) revealed a noticeable increase in the ductile properties, reaching an elongation at break 155% higher than the PLA/TPS blend. Furthermore, contrary to what has been observed with maleinized oils such as linseed oil, the thermal properties do not decrease significantly as a result of the plasticizing effect, due to the compatibilizing behavior of the MHO and the natural antioxidants present in the oil. Finally, a disintegration test was carried out in aerobic conditions at 58 degrees C, for 24 days, to demonstrate that the incorporation of the MHO, although causing a slight delay, does not impair the biodegradability of the blend, obtaining total degradation in 24 days.M. Herrero-Herrero wishes to thank Ministerio de Economia y Competitividad for his grant, BES-2016-078024. J. Gomez-Caturla wish to thank Universitat Politecnica de Valencia for his FPI grant.Lerma-Canto, A.; Gómez-Caturla, J.; Herrero-Herrero, M.; Garcia-Garcia, D.; Fombuena, V. (2021). Development of Polylactic Acid Thermoplastic Starch Formulations Using Maleinized Hemp Oil as Biobased Plasticizer. Polymers. 13(9):1-17. https://doi.org/10.3390/polym13091392S11713
Peroxide-Induced Synthesis of Maleic Anhydride-Grafted Poly(butylene succinate) and Its Compatibilizing Effect on Poly(butylene succinate)/Pistachio Shell Flour Composites
[EN] Framing the Circular Bioeconomy, the use of reactive compatibilizers was applied in order to increase the interfacial adhesion and, hence, the physical properties and applications of green composites based on biopolymers and food waste derived lignocellulosic fillers. In this study, poly(butylene succinate) grafted with maleic anhydride (PBS-g-MAH) was successfully synthetized by a reactive melt-mixing process using poly(butylene succinate) (PBS) and maleic anhydride (MAH) that was induced with dicumyl peroxide (DCP) as a radical initiator and based on the formation of macroradicals derived from the hydrogen abstraction of the biopolymer backbone. Then, PBS-g-MAH was used as reactive compatibilizer for PBS filled with different contents of pistachio shell flour (PSF) during melt extrusion. As confirmed by Fourier transform infrared (FTIR), PBS-g-MAH acted as a bridge between the two composite phases since it was readily soluble in PBS and could successfully form new esters by reaction of its multiple MAH groups with the hydroxyl (-OH) groups present in cellulose or lignin of PSF and the end ones in PBS. The resultant compatibilized green composites were, thereafter, shaped by injection molding into 4-mm thick pieces with a wood-like color. Results showed significant increases in the mechanical and thermomechanical rigidity and hardness, meanwhile variations on the thermal stability were negligible. The enhancement observed was related to the good dispersion and the improved filler-matrix interfacial interactions achieved by PBS-g-MAH and also to the PSF nucleating effect that increased the PBS's crystallinity. Furthermore, water uptake of the pieces progressively increased as a function of the filler content, whereas the disintegration in controlled compost soil was limited due to their large thickness.This research was funded by the Ministry of Science and Innovation (MICI) project number MAT2017-84909-C2-2-R.Rojas-Lema, SP.; Arévalo, J.; Gómez-Caturla, J.; Garcia-Garcia, D.; Torres-Giner, S. (2021). Peroxide-Induced Synthesis of Maleic Anhydride-Grafted Poly(butylene succinate) and Its Compatibilizing Effect on Poly(butylene succinate)/Pistachio Shell Flour Composites. Molecules. 26(19):1-28. https://doi.org/10.3390/molecules26195927S128261
Improvement of Impact Strength of Polylactide Blends with a Thermoplastic Elastomer Compatibilized with Biobased Maleinized Linseed Oil for Applications in Rigid Packaging
[EN] This research work reports the potential of maleinized linseed oil (MLO) as biobased compatibilizer in polylactide (PLA) and a thermoplastic elastomer, namely, polystyrene¿b¿(ethylene¿ran¿butylene)¿b¿styrene (SEBS) blends (PLA/SEBS), with improved impact strength for the packaging industry. The effects of MLO are compared with a conventional polystyrene¿b¿poly(ethylene¿ran¿butylene)¿b¿polystyrene¿graft¿maleic anhydride terpolymer (SEBS¿g¿MA) since it is widely used in these blends. Uncompatibilized and compatibilized PLA/SEBS blends can be manufactured by extrusion and then shaped into standard samples for further characterization by mechanical, thermal, morphological, dynamical¿mechanical, wetting and colour standard tests. The obtained results indicate that the uncompatibilized PLA/SEBS blend containing 20 wt.% SEBS gives improved toughness (4.8 kJ/m2) compared to neat PLA (1.3 kJ/m2). Nevertheless, the same blend compatibilized with MLO leads to an increase in impact strength up to 6.1 kJ/m2, thus giving evidence of the potential of MLO to compete with other petroleum¿ derived compatibilizers to obtain tough PLA formulations. MLO also provides increased ductile properties, since neat PLA is a brittle polymer with an elongation at break of 7.4%, while its blend with 20 wt.% SEBS and MLO as compatibilizer offers an elongation at break of 50.2%, much higher than that provided by typical SEBS¿g¿MA compatibilizer (10.1%). MLO provides a slight decrease (about 3 °C lower) in the glass transition temperature (Tg) of the PLA¿rich phase, thus showing some plasticization effects. Although MLO addition leads to some yellowing due to its intrinsic yellow colour, this can contribute to serving as a UV light barrier with interesting applications in the packaging industry. Therefore, MLO represents a cost¿effective and sustainable solution to the use of conventional petroleum¿derived compatibilizers.This research was funded by the Ministry of Science, Innovation, and Universities (MICIU) project number MAT2017-84909-C2-2-RTejada-Oliveros, R.; Balart, R.; Ivorra-Martínez, J.; Gómez-Caturla, J.; Montanes, N.; Quiles-Carrillo, L. (2021). Improvement of Impact Strength of Polylactide Blends with a Thermoplastic Elastomer Compatibilized with Biobased Maleinized Linseed Oil for Applications in Rigid Packaging. Molecules. 26(1):1-19. https://doi.org/10.3390/molecules26010240S11926
The effects of processing parameters on mechanical properties of 3D-printed polyhydroxyalkanoates parts
[EN] The crystallisation process of polyhydroxyalkanoates (PHA) polymers plays a key role on final properties of manufactured parts due to most PHA are highly sensitive to physical aging which leads to embrittlement. The secondary crystallisation associated with the aging process can be partially controlled by the cooling process during manufacturing or, even, by heat treatments such as annealing. A critical parameter in additive manufacturing is the difficulty to achieve good adhesion of the material to the printing bed. The bed temperature plays a key role on PHBH crystallisation, which leads to shrinkage having a negative effect on polymer-to-bed adhesion. In this work, a study of the effect of different processing parameters such as the printing temperature, the bed temperature, the cooling conditions, as well as raster direction on the final properties of PHBH 3D-printed parts is carried out.This research is a part of the grant PID2020-116496RB-C22
funded by MCIN/AEI/10.13039/501100011033. Authors also
thank Generalitat Valenciana-GVA for funding this research
through the grant numbers AICO/2021/025 and CIGE/2021/
094. Wants to thank the Ministerio de Ciencia e Innovación
and Universities for his FPU grant (FPU19/01759). Wants to
thank Generalitat Valenciana-GVA, for his FPI grant (ACIF/2021/
185) and grant FPU20/01732 funded by MCIN/AEI/10.13039/
501100011033 and by ESF Investing in your future. Funding
for open access charge: Universitat Politècnica de València.Ivorra-Martinez, J.; Peydro, MA.; Gómez-Caturla, J.; Sanchez-Nacher, L.; Boronat, T.; Balart, R. (2023). The effects of processing parameters on mechanical properties of 3D-printed polyhydroxyalkanoates parts. Virtual and Physical Prototyping (Online). 18(1). https://doi.org/10.1080/17452759.2022.216473418
- …