Alertas Tecnológicas 2017

Enero-Marzo 1er Trimestre


Enzimas para degradación de plásticos, encapsulación de enzimas, degradación de plásticos, alternativas a los vertidos de plásticos, regeneración medioambiental, obtención de plásticos biodegradables

Current Biology

Polyethylene bio-degradation by caterpillars of the wax moth Galleria mellonella 

Paolo Bombelli, Christopher J. Howe'Correspondence information about the author Christopher J. Howe Email the author Christopher J. Howe, Federica Bertocchini3, 'Correspondence information about the author Federica Bertocchini Email the author Federica Bertocchini 3Lead contact. DOI: http://dx.doi.org/10.1016/j.cub.2017.02.060 |Paolo Bombelli, Christopher J. Howe' Correspondence information about the author Christopher J. HoweEmail the author Christopher J. Howe, Federica Bertocchini3, 'Correspondence information about the author Federica BertocchiniEmail the author Federica Bertocchini 3Lead contact. DOI: http://dx.doi.org/10.1016/j.cub.2017.02.060 | Summary

Plastics are synthetic polymers derived from fossil oil and largely resistant to biodegradation. Polyethylene (PE) and polypropylene (PP) represent 92% of total plastic production. PE is largely utilized in packaging, representing 40% of total demand for plastic products (www.plasticseurope.org) with over a trillion plastic bags used every year [1]. Plastic production has increased exponentially in the past 50 years (Figure S1A in Supplemental Information, published with this article online). In the 27 EU countries plus Norway and Switzerland up to 38% of plastic is discarded in landfills, with the rest utilized for recycling (26%) and energy recovery (36%) via combustion (www.plasticseurope.org), carrying a heavy environmental impact. Therefore, new solutions for plastic degradation are urgently needed. We report the fast biodegradation of PE by larvae of the wax moth Galleria mellonella, producing ethylene glycol.


Diseño de nuevas protecciones en cascos de motocicleta o deportivos, nuevos polímeros con propiedades viscoelásticas de disipación de energía en impactos.

Journal of the Mechanics and Physics of Solids

Tanaz Rahimzadeha, Ellen M. Arrudaa,b, c, , , M.D. Thoulessa, d, ,a Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI 48109, USA b Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109, USA c Macromolecular Science & Engineering Program, University of Michigan, Ann Arbor, MI 48109, USA d Department of Materials Science & Engineering, University of Michigan, Ann Arbor, MI 48109, USA https://doi.org/10.1016/j.jmps.2015.09.009 Abstract

The features of blast and impact that can damage a delicate target supported by a structure include both the peak pressure and the impulse delivered to the structure. This study examines how layers of elastic and visco-elastic materials may be assembled to mitigate these features. The impedance mismatch between two elastic layers is known to reduce the pressure, but dissipation is required to mitigate the transmitted impulse in light-weight armor. A novel design concept called impact or blast tuning is introduced in which a multi-layered armor is used to tune the stress waves resulting from an impact or blast to specific frequencies that match the damping frequencies of visco-elastic layers. The material and geometrical parameters controlling the viscous dissipation of the energy within the armor are identified for a simplified one-dimensional system, to provide insight into how the optimal design of multi-use armor might be based on this concept.


Nuevos polímeros orgánicos, con propiedades mejoradas de porosidad y resistencia térmica, más ligeros que los polímeros tradicionales, Nuevas funcionalidades poliméricas como fluorescencia, conductividad eléctrica o iónica y actividad catalítica

Chemical Communications

David Rodríguez-San-Miguel, a Afshin Abrishamkar,bc Jorge A. R. Navarro,d Romen Rodriguez-Trujillo,e David B. Amabilino,f Ruben Mas-Ballesté,*a Félix Zamora*agh and Josep Puigmartí-Luis* b Corresponding authors a Departamento de Química Inorgánica, Universidad Autónoma de Madrid, 28049 Madrid, Spain E-mail: [email protected], [email protected] b Empa, Swiss Federal Laboratories for Materials Science and Technology, Lerchenfeldstrasse 5, 9014 St. Gallen, Switzerland E-mail: [email protected] c Department of Chemistry and Applied Biosciences, Institute for Chemical and Bioengineering, ETH Zurich, Vladimir Prelog Weg 1, 8093 Zurich, Switzerland d Departamento de Química Inorgánica, Universidad de Granada, 18071 Granada, Spain e Institut de Ciència de Materials de Barcelona (ICMAB-CSIC), Campus Universitari de Bellaterra, 08193 Cerdanyola del Vallès, Spain f School of Chemistry, The University of Nottingham, University Park, UK g Condensed Matter Physics Center (IFMAC), Universidad Autónoma de Madrid, 28049 Madrid, Spain h Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA Nanociencia), Cantoblanco, 28049 Madrid, Spain Abstract

A microfluidic chip has been used to prepare fibres of a porous polymer with high structural order, setting a precedent for the generation of a wide variety of materials using this reagent mixing approach that provides unique materials not accessible easily through bulk processes. The reaction between 1,3,5-tris (4-aminophenyl) benzene and 1,3,5-benzenetricarbaldehyde in acetic acid under continuous microfluidic flow conditions leads to the formation of a highly crystalline and porous covalent organic framework (hereafter denoted as MF-COF-1), consisting of fibrillar micro-structures, which have mechanical stability that allows for direct drawing of objects on a surface.


Nuevos desarrollos y aplicaciones en polímeros biodegradables

References

http://www.marketsandmarkets.com/PressR e le ases/renewable-chemical.asp

http://www.marketsandmarkets.com/Market-Reports/global-specialty-chemicals-165.html

http://aijn.org/articles/ph-bottle-project/

http://phbottle.eu/

http://carbioproject.com/

http://www.compositesevolution.com/news/carbio-project-develops-carbonflax hybridautomotive-roof/

http://www.dibbiopack.eu/

http://www.innorex.eu/

http://www.placard-ecoinnovation.eu/

http://www.usda.gov/wps/portal/usda/usdahome?contentid=2016/05/0122.xml&contentidonly=true




Abril-Junio 2º Trimestre



Enzimas y degradación de plásticos, encapsulación de enzimas, degradación de plásticos, alternativas a los vertidos plásticos, regeneración medioambiental, obtención de plásticos biodegradables.

Degradation profiles of biodegradable plastic films by biodegradable plastic-degrading enzymes from the yeast Pseudozyma antarctica and the fungus Paraphoma sp. B47-9. Polymer Degradation and Stability, 141, 26-32.

Sato, S., Saika, A., Shinozaki, Y., Watanabe, T., Suzuki, K., Sameshima-Yamashita, Y., ... & Kitamoto, H. (2017).

Agricultural mulch films made from biodegradable polymers (BP) have been used to decrease the burden of plastic waste recovery and recycling. However, their degradations depend largely on environmental conditions and sometimes do not proceed as desired. Yeast strains of Pseudozyma antarctica often isolated from rice husks were found to secrete an esterase to degrade BP films. Poly-butylene succinate-co-adipate (PBSA) films buried in unsterilized rice husks with 60% (w/w) moisture degraded rapidly compared to that buried in field soil. The type strain of P. antarctica JCM 10317 added as cell suspension onto sterilized rice husks with PBSA film grew rapidly forming filamentous growth on the surface of rice husks and films. BP-degrading enzyme secreted by the growing cells was adsorbed on the surface of film and decomposed the film. Addition of rice husk-derived P. antarctica strains also showed BP film degradation activity in sterilized rice husks. In the light of these findings, we suggest that techniques for disposal of used BPs which combine plastics with unutilized residual plant materials piled at the side of agricultural fields be developed.

Marine microbe with potential to adhere and degrade plastic structures. In NGBT conference; Oct (pp. 02-04).

Kumari, A., Chaudhary, D. R., & Jha, B. (2017).

Extensive usages of plastics have led to their accumulation as a contaminant in natural environment worldwide. Plastic is an inert and non-biodegradable material, due to its complex structure and hydrophobic backbone. Conventional methods for reduction of plastic waste such as burning, land-filling release unwanted toxic chemicals to the environment and harming living organism of land as well as the ocean. Thereis growing interest in development of strategies for the degradation of plastic wastes to clean the environment. Marine bacteria have evolved with the capability to adapt and grow in the diverse environmental conditions. We studied the ability of marine bacteria for destabilization and utilization of different plastic films (LDPE, HDPE, PVC and PET)  as  a  sole  source  of  carbon.  An  active  bacterial  strain  AIIW2  was  selected  based  on  the  triphenyl  tetrazolium  chloride reduction assay, and it was identified as Bacillus species based on 16S rRNA gene sequence. The viability of the strain over the plastic surface was studied and confirmed by bacLight assay with fluorescent probes. Scanning Electron Microscope and Atomic Force Microscope images suggested that bacterial interaction over the plastic surface is causing deterioration and roughness with increasing bacterial incubation time. In Fourier transform infrared spectra of treated plastic film evidenced stretching of the (-CH) alkane rock chain and (-CO) carbonyl region, suggested the oxidative activities of the bacteria. The results revealed that ability of bacterial  strain  for  instigating  their  colonization  over  plastic  films  and  deteriorating  the  polymeric  structure  in  the  absence  of other  carbon  sources. Moreover,  production of  extracellular  enzymes  such  as  esterase,  laccase,  and  dehalogenase  which  are reported  to  support  utilization  of  plastics  was  confirmed  by  plate  assays.  In  concise,  our  results  suggested  that  the  marine bacterial strain AIIW2 have the ability to utilize different plastics and dictates the need for the further studies on the underlying biological  process.  We  planned  to  explore  the  genes  encoding  the  enzymes  involved in  degradation  of  plastic  through  whole genome  study  and  metabolic  profiling  to  investigate  any  phenotypic  changes.  Establishing  microbial  resources  for  the degradation of plastics is an ecofriendly approach which could be useful in reduction of its accumulation

Microbial Degradation Of Plastic: A Short Study. RADS Journal of Biological Research & Applied Sciences, 8(1), 32-36.

Ali, H., & Wahab, I. (2017). 

Plastic is also one of the keycauses of ecologicalcontamination. Accumulation of plastic pollutants in the environment becoming an ecological threat. The aim of this study is to isolate plastic degrading organism. Plastic is not broken down the plastic. Absence or low activity of catabolic enzymes that can attack its components. Polyesters containing a High ratio of chemically inert components, such as PET, shown resistance against microbial degradation. Buried soil and shake flask methods were used in this study. Plastic samples were buried and incubated in different soil samples for 3- month intervals. Pseudomonas species (15.2%), Proteus species (26.4%) and Micrococcus species (46.1%) were isolated by the Soil Buried Method. These species were tested forconfirming degradation of plastic by using the Shake Flask Method.

Life in Plastic… It's Fantastic: Degradation of BisphenolA in ElizabethkingiaAnophelis affected by Cefotaxand Imipenem. Proceedings of Freshman Research in Biochemistry, 3(1).

Soliman, S., Matsumoto, K., Wilson, C., Davis, O., Johnson, W., Torres, N., & Canaan, P. (2017).

When researching the Elizabethkingia anophelis R26 genome, we utilized the RAST database and PATRIC database to find a specific pathway that was important in understanding this bascteria. We used the PATRIC database to find five genes from the Bisphenol A degradation pathway, the same chemical that is commonly found in plastic. BPA is a health concern today for  the possible effects it has on our health and brain (1). We each researched a different gene and found what functions they do and what proteins or enzymes they contain. In general, the genes we researched had several similarities, for most of the genes catalyze or reverse certain reactions for a type of alcohol. Also the majority contained the enzyme dehydrogenase, present in four out of the five genes researched (2, 3).After researching each gene and recording all of our data, we went back to the PATRIC database (4) to obtain the DNA sequence of the genes. BLAST allowed us to find our specific genes in the RAST database (5) and view their placement in the E. anophelis genome. The gene numbers from RAST were used to find the RNAseqand record the transcription patterns expressed in Cefotaxand Imipenem. For some genes, their level of expression increased in the presence of Cefotaxand Imipenem, while for others their expression decreased.

Ganesh, P., Dineshraj, D., & Yoganathan, K. (2017). Production and screening of depolymerising enzymes by potential bacteria and fungi isolated from plastic waste dump yard sites. IJAR, 3(3), 693-695.

The   most   alternative   plastic   waste   treatment   method   is   enzymatic   degradation. These   kind   of depolymerising  enzymes  are  effectively  produced  by  some  microorganisms.  This  study  revealed  that, microorganisms produce  depolymerising  enzymes  during  biodegradation  of  polyethylene  carry  bag (PCB).  For  that,  in  sterile  minimal  broth,  pure  culture  of  various  isolates  were  added,  pieces  of  mass polyethylene carry bag films were added and incubated for a month. After the incubation the broth was centrifuged  at  10,000  rpm  for  20  minutes  at  4  °C. The  bacteria Pseudomonas  aeruginosa,  Bacillus sp and fungi Fusarium graminearum were found producing depolymerising enzymes viz., amylase, lignin /manganese  peroxidase  and  laccase  followed  by  others.  These  potential  bacteria  and  fungi  might  be applied for bioremediation in the polyethylene contaminated environments.

Plastics in the North Atlantic garbage patch: a boat-microbe for hitchhikers and plastic degraders. Science of the Total Environment, 599, 1222-1232

Debroas, D., Mone, A., & Ter Halle, A. (2017).

Plastic is a broad name given to different polymers with high molecular weight that impact wildlife. Their fragmentation leads to a continuum of debris sizes (meso to microplastics) entrapped in gyres and colonized by microorganisms. In the present work, the structure of eukaryotes, bacteria and Archaea was studied by a metabarcoding approach, and statistical analysis associated with network building was used to define a core microbiome at the plastic surface. Most of the bacteria significantly associated with the plastic waste originated from non-marine ecosystems, and numerous species can be considered as hitchhikers, whereas others act as keystone species (e.g., Rhodobacterales, Rhizobiales, Streptomycetales and Cyanobacteria) in the biofilm. The chemical analysis provides evidence for a specific colonization of the polymers. Alphaproteobacteria and Gammaproteobacteria significantly dominated mesoplastics consisting of poly(ethylene terephthalate) and polystyrene. Polyethylene was also dominated by these bacterial classes and Actinobacteria. Microplastics were made of polyethylene but differed in their crystallinity, and the majorities were colonized by Betaproteobacteria. Our study indicated that the bacteria inhabiting plastics harboured distinct metabolisms from those present in the surrounding water. For instance, the metabolic pathway involved in xenobiotic degradation was overrepresented on the plastic surface.

Agarose bioplastic_based drug delivery system for surgical and wound dressings. Engineering in Life Sciences, 17(2), 204-214.

Awadhiya, A., Tyeb, S., Rathore, K., & Verma, V. (2017).

We have developed an agarose_based biocompatible drug delivery vehicle. The vehicle is in the form of thin, transparent, strong and flexible films. The biocompatibility and haemocompatibility of the films is confirmed using direct and indirect contact biological assay. Contact angle measurement exhibits hydrophilic nature of the films, and protein adsorption test shows low protein adsorption on the film surface. Drugs, antibiotics and antiseptics, retain their potency after their incorporation into the films. Our bioplastic films can be a versatile medium for drug delivery applications, especially as wound and surgical dressings where a fast drug release rate is desired.

A high heat-resistance bioplastic foam with efficient electromagnetic interference shielding. Chemical Engineering Journal, 323, 29-36.

Cui, C. H., Yan, D. X., Pang, H., Jia, L. C., Xu, X., Yang, S., ... & Li, Z. M. (2017). 

Owing to the growing awareness of sustainability, bioplastic based composites arouse considerable attention. However, the low use temperature (usually <100 °C) limits their applications. To improve the heat resistance and simultaneously meet the lightweight requirement for microwave shielding, a high heat-resistance crystallite, stereocomplex crystallites (sc) formed by the stereocomplexation crystallization between enantiomeric poly(l-lactide) (PLLA) and poly(d-lactide) (PDLA), was introduced into the conductive carbon nanotube (CNT)/poly(lactic acid) (PLA) composite foam. The composite foam was fabricated by a nonsolvent induced phase separation and freeze-drying method. An intriguing phenomenon occurred in the CNT/PLLA/PDLA/dichloromethane (DCM) solution upon addition of hexane, which not only induced the phase separation of mixed solution but also facilitated the formation of 100% sc in the formed crystals in the resultant CNT/PLA/DCM gel. The freeze-dried CNT/PLA foam exhibits a low foam density of 0.10 g/cm3 and desirable specific EMI shielding effectiveness as high as 216 dB cm3/g. More importantly, the formation of sc with high crystallinity (_45%) and the interconnected CNT conductive networks guaranteed the dimensional stability of CNT/PLA foams, only shrinking 4.3% at 220 °C. Our work provides a facile method to fabricate a PLA based bioplastic foam and suggests high heat-resistance and efficient EMI shielding performance.


Nuevos polímeros orgánicos, con propiedades mejoradas de porosidad y resistencia térmica, más ligeros que los polímeros tradicionales, Nuevas funcionalidades poliméricas como fluorescencia, conductividad eléctrica o iónica y actividad catalítica

A supramolecular Tröger's base derived coordination zinc polymer for fluorescent sensing of phenolic-nitroaromatic explosives in water. Chemical science, 8(2), 1535-1546.

Shanmugaraju, S., Dabadie, C., Byrne, K., Savyasachi, A. J., Umadevi, D., Schmitt, W., ... & Gunnlaugsson, T. (2017).

A novel metronidazole fluorescent nanosensor based on graphene quantum dots embedded silica molecularly imprinted polymer. Biosensors and Bioelectronics, 92, 618-623.

Mehrzad-Samarin, M., Faridbod, F., Dezfuli, A. S., & Ganjali, M. R. (2017).

A novel optical nanosensor for detection of Metronidazole in biological samples was reported. Graphene quantum dots embedded silica molecular imprinted polymer (GQDs-embedded SMIP) was synthesized and used as a selective fluorescent probe for Metronidazole detection. The new synthesized GQDs-embedded SMIP showed strong fluorescent emission at 450 nm excited at 365 nm which quenched in presence of Metronidazole as a template molecule.. The quenching was proportional to the concentration of Metronidazole in a linear range of at least 0.2 _M to 15_M. The limit of detection for metronidazole determination was obtained 0.15 _M. The nanosensor successfully worked in plasma matrixes.

Polypyrrole nanotubes: The tuning of morphology and conductivity. Polymer, 113, 247-258.

Sapurina, I., Li, Y., Alekseeva, E., Bober, P., Trchova, M., Moravkova, Z., & Stejskal, J. (2017).

Polypyrrole nanotubes rank among important functional materials with high application potential. They are prepared by the oxidative polymerization of pyrrole usually in the presence of methyl orange and represent conducting polymers with the highest bulk conductivity, 40-50 S cm_1. The role of methyl orange in promoting the nanotubular morphology of polypyrrole is discussed on the basis of FTIR and Raman spectra. The model based on the organization of acid form of methyl orange molecules to an in-situ-generated solid template is proposed. Various factors controlling the morphology and conductivity of polypyrrole have been identified. Higher acidity of reaction medium or the addition of ethylene glycol increased the diameter of nanotubes or even converted nanotubes to globules, and the conductivity was reduced. Nanotubes have not been obtained at temperature elevated to 60 °C but one-dimensional polypyrrole morphology was surprisingly produced even when the oxidation of pyrrole took place in frozen reaction medium, in ice, at _24 °C. The counter-ions in iron(III) salt used for the oxidation and the presence of water-soluble polymers had virtually no influence on morphology and conductivity. On the other hand, a series of organic dyes used as replacement of methyl orange had substantial effect on both the nanotubular morphology and conductivity. The role of template formation is discussed by comparing methyl orange and ethyl orange dyes. While the former dye precipitates under acidic conditions and supports the growth of nanotubes, the latter does not and globules are obtained instead.

Enhancing ionic conductivity in composite polymer electrolytes with well-aligned ceramic nanowires. Nature energy, 2(5), 17035.

Liu, W., Lee, S. W., Lin, D., Shi, F., Wang, S., Sendek, A. D., & Cui, Y. (2017).

In contrast to conventional organic liquid electrolytes that have leakage, flammability and chemical stability issues, solid electrolytes are widely considered as a promising candidate for the development of next-generation safe lithium-ion batteries. In solid polymer electrolytes that contain polymers and lithium salts, inorganic nanoparticles are often used as fillers to improve electrochemical performance, structure stability, and mechanical strength. However, such composite polymer electrolytes generally have low ionic conductivity. Here we report that a composite polymer electrolyte with well-aligned inorganic Li+-conductive nanowires exhibits an ionic conductivity of 6.05 _ 10_5_S_cm-1 at 30__C, which is one order of magnitude higher than previous polymer electrolytes with randomly aligned nanowires. The large conductivity enhancement is ascribed to a fast ion-conducting pathway without crossing junctions on the surfaces of the aligned nanowires. Moreover, the long-term structural stability of the polymer electrolyte is also improved by the use of nanowires.

 

Nuevos desarrollos en polímeros biodegradables

Synthetic biodegradable medical polyurethanes. In Science and Principles of Biodegradable and Bioresorbable Medical Polymers (pp. 189-216).

Chiono, V., Sartori, S., Calzone, S., Boffito, M., Tonda-Turo, C., Mattu, C., ... & Ciardelli, G. (2017).

Polyurethanes (PURs) are a class of block copolymers synthesised from three different reagents: a polyol, a di- or multi-isocyanate, and a chain extender. Biodegradable PURs can be synthesised by properly selecting the building blocks with suitable properties for applications in regenerative medicine. The nature and relative amount of hard and soft segments affect the mechanical properties. PURs can be bulk or surface functionalised with biomimetic peptide sequences or natural polymers, affecting cell response and/or the biodegradation rate. PUR particles, fibres, and hydrogels can be designed with a suitable composition for drug encapsulation and controlled release. This chapter offers an overview of the chemistry of biodegradable and biocompatible PURs and reports their application as scaffolds for tissue engineering and carriers for drug delivery.

Synthetic biodegradable medical polyesters: poly (trimethylene carbonate). In Science and Principles of Biodegradable and Bioresorbable Medical Polymers (pp. 107-152).

Dobrzynski, P., Kasperczyk, J., & Li, S. (2017).

Degradable aliphatic poly(trimethylene carbonate) (PTMC) and poly(carbonate-co-esters) of trimethylene carbonate (TMC) with lactides, glycolide, and _-carprolactone present great interest for applications in the fields of surgery, tissue repair and regeneration, tissue engineering, and sustained drug delivery. This chapter aims to provide a comprehensive review on the state-of-the-art of the synthesis mechanisms, structure-properties, degradation behaviours, and biomedical applications of TMC-based polymers. The ring-opening polymerisation mechanisms are discussed in detail, including anionic, cationic, coordination, and enzyme-catalysed polymerisation. The in vitro and in vivo degradation of PTMC and copolymers are described. PTMC homopolymer can be degraded in vivo or in the presence of enzymes. Degradation of copoly(carbonate-esters) is similar to that of aliphatic polyesters involving water uptake, molar mass decrease, weight loss, and morphological and compositional changes. Understanding of the degradation characteristics is of key importance for the development of medical and pharmaceutical applications.

Biodegradable and biocompatible polymers for tissue engineering application: a review. Artificial cells, nanomedicine, and biotechnology, 45(2), 185-192.

Asghari, F., Samiei, M., Adibkia, K., Akbarzadeh, A., & Davaran, S. (2017).

Since so many years ago, tissue damages that are caused owing to various reasons attract scientists' attention to find a practical way to treat. In this regard, many studies were conducted. Nano scientists also suggested some ways and the newest one is called tissue engineering. They use biodegradable polymers in order to replace damaged structures in tissues to make it practical. Biodegradable polymers are dominant scaffolding materials in tissue engineering field. In this review, we explained about biodegradable polymers and their application as scaffolds.

Synthetic biodegradable medical polyesters. In Science and Principles of Biodegradable and Bioresorbable Medical Polymers (pp. 37-78).

Li, S. (2017).

Degradable and bioresorbable aliphatic polyesters present great interest for biomedical and pharmaceutical applications. Among them, polylactide or poly(lactic acid) (PLA), polyglycolide or poly(glycolic acid) (PGA), and their copolymers are most attractive because of their outstanding biocompatibility, degradability, and versatility concerning physico-chemical and mechanical properties. This chapter aims to provide a comprehensive review on the state-of-the-art of PLA/PGA polymers, including the synthesis, properties, degradation, and applications. Efforts are focused on detailing the degradation mechanism and the effects of various factors such as PLA configuration, morphology, stereocomplexation, and chemical composition on the degradation behaviours. Hydrolytic degradation of large-size PLA/PGA polymers is characterised by autocatalysis of carboxyl end groups generated by ester bond cleavage. Faster internal degradation and degradation-induced morphological and compositional changes are three of the most important phenomena deduced from the behaviours of various polyesters. These findings should allow to predict the degradation of PLA/PGA polymers, which is of key importance for specific applications.



Julio-Septiembre 3er Trimestre



Enzimas y degradación de plásticos, encapsulación de enzimas, degradación de plásticos, alternativas a los vertidos plásticos, regeneración medioambiental, obtención de plásticos biodegradables.

Enzyme-assisted polymer film degradation-enabled biomolecule sensing with poly (N-isopropylacrylamide)-based optical devices. Analytica chimica acta, 999, 139-143.

Zhang, W., Wei, M., Carvalho, W. S., & Serpe, M. J. (2018).

A biosensor for mouse Immunoglobulin G (IgG) was generated from responsive polymer-based interference filters (etalons). To accomplish this, an excess amount of alkaline phosphatase-modified goat anti-mouse IgG (AP-GAM, F(abâÄô)2 fragment specific to mouse IgG) was added to mouse IgG, and allowed to react for some time. After a given reaction time, the bound AP-GAM could be isolated from the unbound, excess AP-GAM by addition of goat anti-mouse IgG (Fc fragment specific)-modified magnetic microspheres (GAM-M) that bind the mouse IgG bound to AP-GAM. After application of a magnetic field, the free, unbound AP-GAM was isolated from the mixture and exposed to an etalon that has its upper Au surface modified with phosphate-containing polymer that can be degraded by AP-GAM. By the phosphate-containing polymer being degraded by the excess AP-GAM, the cleaved phosphate groups can diffuse into the interference filter's active polymer layer that yields a change in the optical properties that can be related to the amount of IgG in the sample. This concept is extremely straightforward to implement, and can be modified to detect a variety of other analytes of interest.

Application of ammonia pretreatment to enable enzymatic hydrolysis of hardwood biomass. Polymer Degradation and Stability, 148, 19-25.

Sakuragi, K., Igarashi, K., & Samejima, M. (2018).

Ammonia pretreatment greatly improves enzymatic hydrolysis of grass biomass, but is reported to be ineffective for hardwood biomass. Here, we examined the effectiveness of ammonia pretreatment of biomass from six hardwood species with different contents of xylan and lignin. Ammonia pretreatment greatly improved enzymatic hydrolysis of polysaccharides in birch and willow, but was less effective for acacia, eucalyptus, and poplar. The effectiveness of ammonia pretreatment increased with xylan content but decreased with lignin content of the hardwood species. By adding a recombinant xylanase to the commercial enzyme digestion cocktail, the yield of enzymatic hydrolysis of ammonia-pretreated birch biomass was improved to a similar level to that obtained with grass biomass. Our results indicate that enzymatic hydrolysis of biomass from hardwood species having a relatively high xylan/lignin ratio can be achieved with a xylanase-enriched enzyme cocktail after ammonia pretreatment.

Effect of Hydroxyl Monomers on the Enzymatic Degradation of Poly (ethylene succinate), Poly (butylene succinate), and Poly (hexylene succinate). Polymers, 10(1), 90.

Bai, Z., Liu, Y., Su, T., & Wang, Z. (2018).

Poly(ethylene succinate) (PES), poly(butylene succinate) (PBS), and poly(hexylene succinate) (PHS), were synthesized using succinic acid and different dihydric alcohols as materials. Enzymatic degradability by cutinase of the three kinds of polyesters was studied, as well as their solid-state properties. The biodegradation behavior relied heavily on the distance between ester groups, crystallinity, and the hydrophilicity-hydrophobicity balance of polyester surfaces. The weight loss through degradation of the three kinds of polyesters with different hydroxyl monomers took place in the order PHS > PBS > PES. The degradation behavior of the polyesters before and after degradation was analyzed by scanning electron microscopy, differential scanning calorimetry, powder X-ray diffraction, Fourier transform infrared spectroscopy, gel permeation chromatography, and thermogravimetric analysis. The decrease in relative intensity at 1800-1650 estedpolyesters were degraded simultaneously. The frequencies of the crystalline and amorphous bands were almost identical before and after degradation. Thus, enzymatic degradation did not change the crystalline structure but destroyed it, and the degree of crystallinity markedly decreased. The molecular weight and polydispersity index only changed slightly. The thermal stability of the three kinds of polyesters decreased during enzymatic degradation.


Nuevos polímeros orgánicos, con propiedades mejoradas de porosidad y resistencia térmica, más ligeros que los polímeros tradicionales, Nuevas funcionalidades poliméricas como fluorescencia, conductividad eléctrica o iónica y actividad catalítica

Intrinsic conductivity mechanisms of radical polymer films with conjugated and non-conjugated backbones. Bulletin of the American Physical Society.

Park, A., Zhang, Y., Cintora, A., McMillan, S., Harmon, N., Moehle, A., ... & Fuchs, G. (2018).

Radical polymers, which incorporate a stable radical pendent group such as 2,2,6,6-tetramethyl pipiridine-1-oxyl (TEMPO), form as class of non-toxic, environmentally friendly materials for battery electrodes. Their conductivity in the solid phase, while critical for battery electrode applications because of the need to collect current, have been controversial. Here we discuss our study of DC conductivity in several species of radical polymers. First, we prepared poly(2,2,6,6-tetramethylpiperidinyloxy methacrylate) (PTMA) using several synthetic methods to examine if the previously proposed redox hopping mechanism is sensitive to the preparation details. We found that PTMA is an insulator, implying that few radical sites participate in conductivity. In search of a radical polymer with higher conductivity, we also investigated the properties of a radical polymer with a conjugated backbone. Our results show that although introducing conjugation to the backbone is a route to introduce conductivity to a radical polymer, the steric hindrance from the TEMPO groups limit the size of the ordered conjugated crystal domains and thus severely reduce the conductivity as compared to the conjugated backbone without TEMPO.

A facile approach towards fabrication of lightweight biodegradable poly (butylene succinate)/carbon fiber composite foams with high electrical conductivity and strength. Composites Science and Technology

Kuang, T., Ju, J., Yang, Z., Geng, L., & Peng, X. (2018). .

Lightweight electrically conductive biodegradable polymer composites have been considered as a promising environmental-friendly alternative to replace the traditional petroleum-based CPCs because of the economic and ecological drawbacks of petroleum-based plastics. Herein, we demonstrated a facile and effective way to fabricate poly (butylene succinate) (PBS)/carbon fiber (CF) composites foams with lightweight, high-strength and improved conductive networks through the combination of solvent mixing, micro-injection molding and supercritical carbon dioxide (ScCO2) foaming methods. Results showed that the resulting composite foams possessed much higher electrical conductivity (the percolation threshold decreased from 3.6 to 7.4 to 1.04-2.37_vol%), suggesting that the introduction of foaming technique could be beneficial for the formation of effective 3D conductivity networks. The composite foams presented a good compressive strength and a low density (reduced around _50%). Moreover, effects of different length and content of CF on the mechanical and thermal performance, rheological behavior, foaming properties and electrical conductivities of PBS/CF composites have been investigated.

Biodegradable Polymeric Materials in Degradable Electronic Devices. ACS Central Science.

Feig, V. R., Tran, H., & Bao, Z. (2018).

Biodegradable electronics have great potential to reduce the environmental footprint of devices and enable advanced health monitoring and therapeutic technologies. Complex biodegradable electronics require biodegradable substrates, insulators, conductors, and semiconductors, all of which comprise the fundamental building blocks of devices. This review will survey recent trends in the strategies used to fabricate biodegradable forms of each of these components. Polymers that can disintegrate without full chemical breakdown (type I), as well as those that can be recycled into monomeric and oligomeric building blocks (type II), will be discussed. Type I degradation is typically achieved with engineering and material science based strategies, whereas type II degradation often requires deliberate synthetic approaches. Notably, unconventional degradable linkages capable of maintaining long-range conjugation have been relatively unexplored, yet may enable fully biodegradable conductors and semiconductors with uncompromised electrical properties. While substantial progress has been made in developing degradable device components, the electrical and mechanical properties of these materials must be improved before fully degradable complex electronics can be realized.

Rotaxanes As Mechanochromic Fluorescent Force Transducers in Polymers. Journal of the American Chemical Society.

Sagara, Y., Karman, M., Verde-Sesto, E., Matsuo, K., Kim, Y., Tamaoki, N., & Weder, C. (2018).

The integration of mechanophores, motifs that transduce mechanical forces into chemical reactions, allows creating materials with stress-dependent properties. Typical mechanophores are activated by cleaving weak covalent bonds, but these reactions can also be triggered by other stimuli, and this renders the behavior unspecific. Here we show that this problem can be overcome by extending the molecular-shuttle function of rotaxanes to mechanical activation. A mechanically interlocked mechanophore composed of a fluorophore-carrying macrocycle and a dumbbell-shaped molecule containing a matching quencher was integrated into a polyurethane elastomer. Deformation of this polymer causes a fluorescence turn-on, due to the spatial separation of fluorophore and quencher. This process is specific, efficient, instantly reversible, and elicits an easily detectable optical signal that correlates with the applied force.


Nuevos desarrollos en polímeros biodegradables

Synthesis, characterization and application of biodegradable polymer grafted novel bioprosthetic tissue. Journal of Biomaterials Science, Polymer Edition, 29(3), 217-235.

Pal, A., Pathak, C., & Vernon, B. (2018).

Animal tissue has an extended history of clinical use in applications like heart valve bioprosthesis devices, cardiovascular surgical applications etc. but often does not last long after implantation in the body due to rapid unwanted degradation. The goal of this work is to develop novel composite biomaterials by grafting biological tissue with synthetic, biodegradable polymers. In the current research phase, porcine submucosa, ureter and bovine pericardial tissue are grafted with poly DL-lactide (PLA), poly glycolide (PGA) and poly DL-lactide glycolide (PLGA) copolymers. The grafted and control tissues are characterized by FTIR and SEM. The biodegradability of the tissue-graft composite materials is determined by pepsin and collagenase digestion assays, showing it can be tailored by varying the grafted polymer type and amount. The grafted tissues can be tuned for a particular clinical or tissue engineering applications including drug delivery with little or no burst release and sustained/controlled delivery.

Cellulose Reinforced Biodegradable Polymer Composite Film for Packaging Applications. In Bionanocomposites for Packaging Applications (pp. 49-69). Springer, Cham.

Khalil, H. A., Tye, Y. Y., Leh, C. P., Saurabh, C. K., Ariffin, F., Fizree, H. M., ... & Suriani, A. B. (2018).

This chapter provides a broad overview of bionanocomposite film prepared from various biodegradable polymers reinforced with nanocellulose. In nature, biodegradable polymer exhibits relatively weaker properties than the synthetic polymers. Incorporation of cellulose into the biopolymer matrix has improved the mechanical, thermal, and barrier properties of the resulting biopolymer film significantly. This achievement has encouraged their application as packaging material. Since they have a huge potential in the future, further investigation of this composite material is crucial.

The Response of Manicaria saccifera Natural Fabric Reinforced PLA Composites to Impact by Fragment Simulating Projectiles. In Advances in Natural Fibre Composites (pp. 89-98). Springer, Cham.

Quintero, S., Porras, A., Hernandez, C., & Maranon, A. (2018).

This chapter presents the impact behavior of a recently developed green composite material made of Manicaria saccifera natural fabric reinforced Poly-Lactic Acid (PLA). Composite coupons made of PLA and Manicaria saccifera fabric were produced by compression molding using the film stacking method. The composite ballistic limit (V50) was determined by subjecting PLA/Manicaria coupons, of varying lay-ups and thicknesses, to ballistic impact loading using fragment simulating projectiles (FSPs) according to the MIL-STD-662F standard. It was found that coupons with areal densities between 0.2 and 0.3 g/cm2 displayed a V50 between 50 and 70 m/s. Also, it was found that the V50 increased nonlinearly as a function of coupon thickness, but it does not depend on the composite stacking sequence. Finally, the energy absorbed by the material at impact on complete penetrations is uniform and independent of the striking velocity, whereas for partial penetrations increases exponentially.



Octubre-Diciembre 4º Trimestre



Enzimas y degradación de plásticos, encapsulación de enzimas, degradación de plásticos, alternativas a los vertidos plásticos, regeneración medioambiental, obtención de plásticos biodegradables.

Microbial Degradation of HDPE Secondary Microplastics: Preliminary Results. In Proceedings of the International Conference on Microplastic Pollution in the Mediterranean Sea (pp. 181-188). Springer, Cham.

Tsiota, P., Karkanorachaki, K., Syranidou, E., Franchini, M., & Kalogerakis, N. (2018).

Plastic debris represents a significant problem among the various problems facing the marine environment. In this work, we aim to explore the ability of two marine indigenous communities to degrade secondary microplastics. Polyethylene (low-density as well as high-density polyethylene) films were exposed to UV radiation until they were fragmented to microplastics under mild mechanical stress. Next, 50mg of sterile microplastics with size 2 mm-250 _m was added into sterile flasks and was incubated separately with these two pelagic microbiomes. A significant decrease in the weight of microplastics was determined along the experimental period, implying the potential ability of indigenous communities to in situ degrade secondary microplastics. Moreover, the protein content marginally decreased while carbohydrate content of both treatments increased at this time interval. Accordingly, the populations increased along experimental period.

Impact of Nanoclays on the Biodegradation of Poly (Lactic Acid) Nanocomposites. Polymers, 10(2), 202.

Castro-Aguirre, E., Auras, R., Selke, S., Rubino, M., & Marsh, T. (2018). 

Poly(lactic acid) (PLA), a well-known biodegradable and compostable polymer, was used in this study as a model system to determine if the addition of nanoclays affects its biodegradation in simulated composting conditions and whether the nanoclays impact the microbial population in a compost environment. Three different nanoclays were studied due to their different surface characteristics but similar chemistry: organo-modified montmorillonite (OMMT), Halloysite nanotubes (HNT), and Laponite® RD (LRD). Additionally, the organo-modifier of MMT, methyl, tallow, bis-2-hydroxyethyl, quaternary ammonium (QAC), was studied. PLA and PLA bio-nanocomposite (BNC) films were produced, characterized, and used for biodegradation evaluation with an in-house built direct measurement respirometer (DMR) following the analysis of evolved CO2 approach. A biofilm formation essay and scanning electron microscopy were used to evaluate microbial attachment on the surface of PLA and BNCs. The results obtained from four different biodegradation tests with PLA and its BNCs showed a significantly higher mineralization of the films containing nanoclay in comparison to the pristine PLA during the first three to four weeks of testing, mainly attributed to the reduction in the PLA lag time. The effect of the nanoclays on the initial molecular weight during processing played a crucial role in the evolution of CO2. PLA-LRD5 had the greatest microbial attachment on the surface as confirmed by the biofilm test and the SEM micrographs, while PLA-QAC0.4 had the lowest biofilm formation that may be attributed to the inhibitory effect also found during the biodegradation test when the QAC was tested by itself.

Carbon and nitrogen mineralization and enzyme activities in soil aggregate-size classes: Effects of biochar, oyster shells, and polymers. Chemosphere.

Awad, Y. M., Lee, S. S., Kim, K. H., Ok, Y. S., & Kuzyakov, Y. (2018). 

Biochar (BC) and polymers are cost-effective additives for soil quality improvement and long-term sustainability. The additional use of the oyster shells (OS) powder in BC- or polymer-treated soils is recommended as a nutrient source, to enhance aggregation and to increase enzyme activities. The effects of soil treatments (i.e., BC (5_Mg_ha_1) and polymers (biopolymer at 0.4_Mg_ha_1 or polyacrylamide at 0.4_Mg_ha_1) with or without the OS (1%)) on the short-term changes were evaluated based on a 30-day incubation experiment with respect to several variables (e.g., CO2 release, NH4+ and NO3_ concentrations, aggregate-size classes, and enzyme activities in an agricultural Luvisol). The BC and BP with the addition of OS increased the portion of microaggregates (<0.25_mm) relative to the control soil without any additions, while PAM alone increased the portion of large macroaggregates (1-2_mm). Concentrations of NO3_ also increased in soils treated with OS, OS + BC, and OS + BP as result of the increased chitinase and leucine aminopeptidase activities. The BC and BP when treated with the additional OS had significant short-term impacts on N mineralization without affecting C mineralization in soil. Consequently, the combination of BC or BP with OS was seen to accelerate N turnover without affecting C turnover (and related C losses) from soil. As such, the addition of these additives contributed considerably to the improvement of soil fertility and C sequestration.

Towards improved predictions for the enzymatic chain-end scission of natural polymers by population balances: The need for a non-classical rate kernel. Chemical Engineering Science, 176, 329-342.

Ho, Y. K., Kirse, C., Briesen, H., Singh, M., Chan, C. H., & Kow, K. W. (2018).

 

Enzymatic chain-end depolymerization is commonly employed for the transformation of biomass into important products. To date, investigation on the validity of the rate kernel which is critical to model success, has been conveniently avoided. Through a case study with extensive confrontation with experimental data, we uncover this critical relationship by inspecting every minute detail in the mechanistic modelling procedure. Using a newly proposed shape-evolving function for the rate kernel, model calibration reveals that the commonly employed constant rate kernel is inappropriate for modelling the scission step, and that the apparent rate kernel of hydrolysis resembles an endothermic activation energy barrier function. Facilitated by the adoption of this non-classical rate kernel, good predictions are attained by the model at different hydrolysis conditions with a global parameter set. Being the first to predict distributed data, the methodology here serves as a guide for future studies on the enzymatic disruption of polymeric biomass, i.e. for guiding substrate and enzyme structure modifications.


Nuevos polímeros orgánicos, con propiedades mejoradas de porosidad y resistencia térmica, más ligeros que los polímeros tradicionales, Nuevas funcionalidades poliméricas como fluorescencia, conductividad eléctrica o iónica y actividad catalítica

Improved dielectric properties, mechanical properties, and thermal conductivity properties of polymer composites via controlling interfacial compatibility with bio-inspired method. Applied Surface Science.

Ruan, M., Yang, D., Guo, W., Zhang, L., Li, S., Shang, Y., ... & Wang, H. (2018). 

Surface functionalization of Al2O3 nano-particles by mussel-inspired poly(dopamine) (PDA) was developed to improve the dielectric properties, mechanical properties, and thermal conductivity properties of nitrile rubber (NBR) matrix. As strong adhesion of PDA to Al2O3 nano-particles and hydrogen bonds formed by the catechol groups of PDA and the polar acrylonitrile groups of NBR, the dispersion of Al2O3-PDA/NBR composites was improved and the interfacial force between Al2O3-PDA and NBR matrix was enhanced. Thus, the Al2O3-PDA/NBR composites exhibited higher dielectric constant, better mechanical properties, and larger thermal conductivity comparing with Al2O3/NBR composites at the same filler content. The largest thermal conductivity of Al2O3-PDA/NBR composite filled with 30_phr Al2O3-PDA was 0.21_W/m_K, which was 122% times of pure NBR. In addition, the Al2O3-PDA/NBR composite filled with 30_phr Al2O3-PDA displayed a high tensile strength about 2.61_MPa, which was about 255% of pure NBR. This procedure is eco-friendly and easy handling, which provides a promising route to polymer composites in application of thermal conductivity field.

Influence of Nickel zinc Iron oxide Nanoparticles on AC Conductivity and Dielectric Properties of Polypyrrole. Materials Today: Proceedings, 5(1), 2479-2487.

Shanthala, V. S., Devi, S. S., & Murugendrappa, M. V. (2018).

The present study reports on a novel polymer blend electrolyte system comprised of poly(ethylene oxide), poly(vinylidene fluoride) and poly (methyl methacrylate) (PEO/PVdF/PMMA) with potassium iodide, iodine and novel and cost effective organic compounds such as 1-(2-(2-(2-(2-(benzoate)ethoxy)ethoxy)ethoxy)ethoxy) benzene (BEB) and 1-(2-(2-(2-(2-(1H-pyrazol-1-yl)ethoxy)ethoxy)ethoxy)ethyl)-1H-pyrazole (PEP) for dye-sensitized solar cell applications. The influence of the synthesized organic compounds on the ionic and photovoltaic characteristics of the electrolytes was studied. In specific, the PEO/PVdF/PMMA/KI/I2/PEP blend electrolyte exhibited high ionic conductivity of 6.3___10_4_S_cm_1 and the corresponding DSSC demonstrated an enhanced conversion efficiency of 9%. The high photovoltaic conversion efficiency of the cell with the PEP-doped system can be attributed to the higher conductivities in the polymer electrolyte associated with the greater cross-linking and the increased I_/I3_ transportation along the interaction of the tetra ethylene glycol derivative, salt and the polymer matrix.


Nuevos desarrollos en polímeros biodegradables

Biodegradable 3D Printed Polymer Microneedles for Transdermal Drug Delivery. Lab on a Chip.

Luzuriaga, M. A., Berry, D. R., Reagan, J., Smaldone, R. A., & Gassensmith, J. J. (2018).

Biodegradable polymer microneedle (MN) arrays are an emerging class of transdermal drug delivery devices that promise a painless and sanitary alternative to syringes; however, prototyping bespoke needle architectures is expensive and requires production of new master templates. Here, we present a new microfabrication technique for MNs using fused deposition modeling (FDM) 3D printing using polylactic acid, an FDA approved, renewable, biodegradable, thermoplastic material. We show how this natural degradability can be exploited to overcome a key challenge of FDM 3D printing, in particular the low resolution of these printers. We improved the feature size of the printed parts significantly by developing a post fabrication chemical etching protocol, which allowed us to access tip sizes as small as 1 _m. With 3D modeling software, various MN shapes were designed and printed rapidly with custom needle density, length, and shape. Scanning electron microscopy confirmed that our method resulted in needle tip sizes in the range of 1-55 _m, which could successfully penetrate and break off into porcine skin. We have also shown that these MNs have comparable mechanical strengths to currently fabricated MNs and we further demonstrated how the swellability of PLA can be exploited to load small molecule drugs and how its degradability in skin can release those small molecules over time.

Marine Fate of Biodegradable Plastic-Substitution Potential and Ecological Impacts. In Proceedings of the International Conference on Microplastic Pollution in the Mediterranean Sea (pp. 195-197). Springer, Cham.

Lott, C., Eich, A., Pauli, N. C., Mildenberger, T., Laforsch, C., Petermann, J. S., ... & Weber, M. (2018).

Biodegradable plastic is gaining attention, also through market regulation by a growing number of countries. The substitution of conventional plastic by these new materials is discussed as one mitigation measure to the ever-growing global problem of marine plastic litter. Modelling showed that the estimated substitution potential on a global scale might be small, with a contribution of only 0.3% to the total marine debris. However, there are huge potentials for substitution on local level, and for single plastic items and applications of one single polymer. In order to assess the environmental risk of new materials such as biodegradable plastics being introduced to the market and potentially also lost to the environment, in-situ studies of the performance under marine conditions have been conducted. Two studies in the Mediterranean Sea are summarized and the role of biofilm formation and fouling on disintegration are highlighted. Preliminary results of ongoing studies in tropical SE Asia are presented.

Randomized comparison of novel biodegradable polymer and durable polymer_coated cobalt_chromium sirolimus_eluting stents: Three_Year Outcomes of the I_LOVE_IT 2 Trial. Catheterization and Cardiovascular Interventions.

Song, L., Li, J., Guan, C., Jing, Q., Lu, S., Yang, L., ... & Han, Y. (2018). 

We aimed to compare the long-term outcomes of the novel biodegradable polymer cobalt-chromium sirolimus-eluting stent (BP-SES) versus the durable polymer sirolimus-eluting stent (DP-SES) in the I-LOVE-IT2 trial.Comparisons of the long-term safety and efficiency of the BP-DES versus the DP-DES are limited.A total of 2,737 patients eligible for coronary stenting were randomized to the BP-SES or DP-SES group at a 2:1 ratio. The primary endpoint of target lesion failure (TLF) was defined as a composite of cardiac death, target vessel myocardial infarction (MI), or clinically indicated target lesion revascularization.A three-year clinical follow-up period was available for 2,663 (97.3%) patients. There were no significant differences in TLF (8.9% vs. 8.6%, P_=_0.81), patient-oriented composite endpoint (PoCE) (15.2% vs.14.5%, P_=_0.63), or individual components between the BP-SES and DP-SES. Definite/probable stent thrombosis (ST) was low and similar at 3 years (0.8% vs. 1.0%, P_=_0.64). Landmark analysis of 1-3 years showed that the TLF (2.7% vs. 2.6%, P_=_0.81), PoCE (6.2% vs. 5.1%, P_=_0.28), and definite/probable ST (0.4% vs. 0.4%, P_=_1.00) were comparable between the 2 arms.In this prospective randomized trial, the BP-SES showed similar clinical results versus the DP-SES in terms of safety and efficacy outcomes over a 3-year follow-up period. 

High-performance biodegradable polylactide composites fabricated using a novel plasticizer and functionalized eggshell powder. International journal of biological macromolecules, 112, 46-53.

Kong, J., Li, Y., Bai, Y., Li, Z., Cao, Z., Yu, Y., ... & Dong, L. (2018).

A novel polyester poly(diethylene glycol succinate) (PDEGS) was synthesized and evaluated as a plasticizer for polylactide (PLA) in this study. Meanwhile, an effective sustainable filler, functionalized eggshell powder (FES) with a surface layer of calcium phenyphosphonate was also prepared. Then, PLA biocomposites were prepared from FES and PDEGS using a facile melt blending process. The addition of 15_wt% PDEGS as plasticizer showed good miscibility with PLA macromolecules and increased the chain mobility of PLA. The crystallization kinetics of PLA composites revealed that the highly effective nucleating FES significantly improved the crystallization ability of PLA at both of non-isothermal and isothermal conditions. In addition, the effective plasticizer and well-dispersed FES increased the elongation at break from 6% of pure PLA to over 200% for all of the plasticized PLA composites. These biodegradable PLA biocomposites, coupled with excellent crystallization ability and tunable mechanical properties, demonstrate their potential as alternatives to traditional commodity plastics.



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