Submitted Successfully!
To reward your contribution, here is a gift for you: A free trial for our video production service.
Thank you for your contribution! You can also upload a video entry or images related to this topic.
Version Summary Created by Modification Content Size Created at Operation
1
Marco Morreale
 + 1494 word(s) 1494 2021-12-23 07:00:45 |
2 format correct
Catherine Yang
 Meta information modification 1494 2022-01-17 02:48:13 |

Video Upload Options

Do you have a full video?
Send video materials Upload full video

Confirm

Are you sure to Delete?
Yes No
Cite
If you have any further questions, please contact Encyclopedia Editorial Office.
Morreale, M. Biodegradable Polymers. Encyclopedia. Available online: https://encyclopedia.pub/entry/18258 (accessed on 05 July 2024).
Morreale M. Biodegradable Polymers. Encyclopedia. Available at: https://encyclopedia.pub/entry/18258. Accessed July 05, 2024.
Morreale, Marco. "Biodegradable Polymers" Encyclopedia, https://encyclopedia.pub/entry/18258 (accessed July 05, 2024).
Morreale, M. (2022, January 14). Biodegradable Polymers. In Encyclopedia. https://encyclopedia.pub/entry/18258
Morreale, Marco. "Biodegradable Polymers." Encyclopedia. Web. 14 January, 2022.
Biodegradable Polymers
Edit
This entry is adapted from the peer-reviewed paper 10.3390/polym11040651

Biodegradable polymers are those which can degrade into water and carbon dioxide under normal environmental conditions through microbial action, providing compost as a simple and sustainable disposal option.

biodegradable polymers films degradation

1. Introduction

Polymeric films attract a significant degree of interest because of their widespread use in several industrial applications, with particular reference to packaging. Over the last decades, the large use of oil-derived polymers, due to their good mechanical, thermal and barrier properties, as well as their low cost, has led to significant problems in term of production and accumulation of wastes [1][2]. Rising concern about the reduction of waste coming from plastic packaging has encouraged both academia and industry to engage in research focused on polymers coming from natural resources, biodegradable or compostable [3][4][5][6]. Bio-based polymers are those obtained from natural resources, while biodegradable polymers are those which can degrade into water and carbon dioxide under normal environmental conditions through microbial action, providing compost as a simple and sustainable disposal option [7][8][9][10], and all of these can be regarded to as bioplastics. For instance, in the case of food packaging, polymers combining renewable sources and biodegradable nature are preferred [11][12].
The replacement of traditional packaging requires the new biodegradable packaging to guarantee comparable levels of performance and cost [13]. However, bio-based films often show disappointing mechanical, thermal and barrier properties [14]. Therefore, new strategies for the development of materials with suitable properties to replace traditional materials for packaging have attracted many research efforts [15][16][17].
Several biodegradable polymers were developed and many of them showed good potential for several applications. Among them, poly-lactic acid (PLA) probably attracted the greatest interest for several applications; in fact, being bioresorbable and biocompatible, this polyester is mainly employed in biomedicine for the preparation of tissue-engineering scaffolds, drug-delivery devices, biosensors, and is considered one of the most promising for food-packaging applications [18]. It is versatile, compostable, recyclable [19][20][21][22], highly transparent, with a high molecular weight, high resistance to water and good processability; on the other hand, its mechanical and thermal properties are still not suitable for several applications [23][24].
Among the polyesters, poly-caprolactone (PCL) has traditionally found applications in the fields of biomedicine and food packaging. With respect to PLA, it presents lower stiffness and tensile strength but higher stretchability and better processability. Moreover, the temperature required for its melt compounding (below 100 °C) allows it to be incorporated in a broader spectrum of natural additives for food packaging, especially those prone to thermal degradation/deactivation [25].
Poly-butylene adipate-co-terephthalate (PBAT) belongs to biodegradable aliphatic-aromatic polyesters and, thanks to its high ductility, it finds applications in agricultural or food packaging materials and was recently considered as one of the candidate materials for blending with PLA [26][27].
Another promising biodegradable polymer is the MaterBi® or, better, the MaterBi® family, including a series of bioplastics coming from modified starch and/or synthetic biodegradable polyesters [28][29]. It found applications in several fields due to good mechanical properties, thermal stability, barrier properties, as well as good processability and compostability [30][31][32]. Another recent example of biodegradable/compostable polymer is the Bioflex® family, typically based on biodegradable polymers such as PLA and thermoplastic copolyesters, such as PBAT [33][34][35][36][37].

2. Degradation of Biodegradable Polymer-Based Systems

Some studies are available regarding the numerous degradation paths of bioplastic-based systems.
Biodegradable polyesters are prone to several degradation mechanisms that may occur depending on the processing conditions. Hydrolysis of ester linkages is a water-induced degradation mechanism, whose rate and extent depends on water concentration, pH, eventual presence of acid or base catalyst, morphology of the polymer and temperature [38]. Two common degradation pathways are typically proposed for PLA: hydrolytic chain scission (a) and main chain scission, i.e., β-C-H hydrogen transfer (b). Hydrolytic degradation in PLA can take place during melt processing or in aqueous media. In the former case, it can be activated by the presence of moisture at high temperatures, in the latter, hydrolytic reactions display pH-dependent kinetics, being particularly faster under alkaline conditions. In both cases, the degradation determines a dramatic molecular weight reduction and can be easily monitored by spectroscopic measurement of –OH and –COOH groups, since the degradation products are hydroxyl- or carboxyl- terminated PLA. In the case of β-C-H hydrogen transfer, instead, carboxylic acid end groups and vinyl esters are formed. Moreover, at high temperatures (above 200 °C), the main degradation mechanism of PLA is trans-esterification, which leads to the formation of cyclic oligomers.
Similarly, PBAT undergoes hydrolytic degradation owing to the cleavage of ester linkages, which requires the presence of water. However, in the case of PBAT, H2O can even react with the carbonyl groups located in proximity of benzene rings. β-C-H hydrogen transfer reactions are supposed to occur randomly even in PBAT backbone [38].
PCL substantially follows the same mechanisms as those previously discussed for PLA and PBAT, although its higher crystallinity degree results in slower degradation [39].
Hydrolytic degradation of poly(α-hydroxyl) esters can proceed by either surface or bulk degradation pathways, with these latter being regulated by mass transfer phenomena (diffusion) and kinetics of chemical reactions [39]. If the rate of hydrolytic chain scission is faster than that of water diffusion into the polymer bulk, the hydrolysis occurs only at the polymer–liquid interface, thus resulting in the progressive thinning of the sample, whose bulk properties, in terms of molecular weight and crystallinity, remain unaltered. Otherwise, when water diffusion is faster than hydrolytic reactions, hydrolysis takes place randomly throughout the entire polymer bulk. This aspect leads to an overall and uniform decay of molecular weight. Oligomers and monomers that are formed diffuse out, thus causing gradual erosive phenomena until achieving the equilibrium between diffusion and chemical kinetics. Whether this equilibrium is hindered, the accumulation of -OH and -COOH terminated byproducts may trigger an internal autocatalysis that accelerates the bulk degradation with respect to that of the outer layers. In this case, a bimodal distribution of molecular weights would be observed, with a degraded inner core and a less altered skin. As the oligomers become small enough to diffuse throughout the structure, this latter tends to be hollowed.
Enzymatic biodegradation of PCL and PLA is shown to be extremely fast when accomplished by outdoor living organisms (bacteria and fungi), typically present in the soil, whereas biodegradation in the human body, for instance, due to the lack of suitable enzymes, is extremely slow, ranging from 6–12 months for PLA to 2–4 years for PCL, depending on starting crystallinity and molecular weight [40]. In fact, bio-resorbability of these polymers involves a two-stage mechanism: hydrolysis of ester groups occurs in the first stage, while the intracellular digestion is carried out by macrophages only in a subsequent stage, that is when the polymer molecular weight is low enough, and crystallinity degree is extremely high [41].

3. Recycling of Systems Based on Biodegradable Polymers

The use of bioplastic-based packaging allows significant advantages to be obtained in terms of environmental impact related to the entire life cycle of the product [42][43][44][45]. However, this can be further improved if the post-consumption recycling of bioplastic-based systems is carried out [46][47][48][49][50][51][52].
The idea to recycle biodegradable polymers, currently used for several applications [13][50][53][54] may sound odd, considering that polymers are regarded as a sustainable alternative for oil-derived polymers since they come from renewable resources and since they are biodegradable/compostable; however, there are several reasons to suggest that recycling of bioplastics is a sensible strategy. These are mainly related to the growing industrial demand and to the fact that recycling is crucial to the reduction of non-renewable resources consumption (including the energy demand linked with their production). Furthermore, some commercial bioplastics do not undergo severe degradation under normal conditions, and the disposal of bioplastic-made items leads to the disposal of valuable raw secondary materials [55][56][57][58].
Moreover, in view of the rising interest towards polymer nanocomposites, due to their improved mechanical thermal and barrier properties [59][60], some researchers have recently studied the of recycling biobased nanocomposites [19][48][61]. With particular reference to PLA, it is known that this polymer undergoes thermodegradation during melt processing [62][63] and, therefore, its recyclability is strictly related to the actual extent of thermodegradative phenomena during melt processing [62][64][65]. For instance, Tesfaye et al. [61] investigated the effect of silk nanocrystals (SNC) on thermal and rheological properties of PLA subjected to repeated extrusion operations; they found that the presence of SNC slows down the thermal degradation of PLA. Peinado et al. [48] studied the effects of extrusion on the rheological and mechanical properties of PLA filled with nanoclays; they found that, although both PLA and nanocomposites show viscosity decreases after each processing step, there was no major reduction of the mechanical performance.
It was generally observed that upon reprocessing cycles, the properties of biodegradable-based nanocomposites depends on to two opposite effects: (i) chain scission due to thermo-mechanical degradation, and (ii) filler dispersion effect resulting from multiple processing. Although the latter phenomenon may prevail at low reprocessing cycles, the former proves to be dominant at higher cycles. Among possible strategies were proposed the reactive extrusion with chain extenders or branching agents [38] or using stabilizers [66]. However, even a combination of chain extenders and stabilizers may be involved to increase the recyclability and reprocessability of biodegradable polymers.

References

  1. Scaffaro, R.; Maio, A. Optimization of two-step techniques engineered for the preparation of polyamide 6 graphene oxide nanocomposites. Compos. Part B Eng. 2019, 165, 55–64.
  2. Edlund, U.; Lagerberg, T.; Ålander, E. Admicellar polymerization coating of CNF enhances integration in degradable nanocomposites. Biomacromolecules 2019, 20, 684–692.
  3. La Mantia, F.P.; Dintcheva, N.T.; Scaffaro, R.; Marino, R. Morphology and properties of polyethylene/clay nanocomposite drawn fibers. Macromol. Mater. Eng. 2008, 293, 83–91.
  4. La Mantia, F.P.; Marino, R.; Dintcheva, N.T. Morphology modification of polyethylene/clay nanocomposite samples under convergent flow. Macromol. Mater. Eng. 2009, 294, 575–581.
  5. La Mantia, F.P.; Arrigo, R.; Morreale, M. Effect of the orientation and rheological behaviour of biodegradable polymer nanocomposites. Eur. Polym. J. 2014, 54, 11–17.
  6. Dintcheva, N.T.; Marino, R.; La Mantia, F.P. The role of the matrix-filler affinity on morphology and properties of polyethylene/clay and polyethylene/compatibilizer/clay nanocomposites drawn fibers. e-Polymers 2009, 9.
  7. Arrieta, M.P.; Fortunati, E.; Burgos, N.; Peltzer, M.A.; López, J.; Peponi, L. Nanocellulose-Based Polymeric Blends for Food Packaging Applications. In Multifunctional Polymeric Nanocomposites Based on Cellulosic Reinforcements; Elsevier: Amsterdam, The Netherlands, 2016; pp. 205–252.
  8. Auras, R.; Harte, B.; Selke, S. An overview of polylactides as packaging materials. Macromol. Biosci. 2004, 4, 835–864.
  9. Kale, G.; Kijchavengkul, T.; Auras, R.; Rubino, M.; Selke, S.E.; Singh, S.P. Compostability of bioplastic packaging materials: An overview. Macromol. Biosci. 2007, 7, 255–277.
  10. Scaffaro, R.; Lopresti, F.; Maio, A.; Botta, L.; Rigogliuso, S.; Ghersi, G. Electrospun PCL/GO-g-PEG structures: Processing-morphology-properties relationships. Compos. Part A Appl. Sci. Manuf. 2017, 92, 97–107.
  11. Scaffaro, R.; Maio, A.; Lopresti, F. Physical properties of green composites based on poly-lactic acid or Mater-Bi® filled with Posidonia Oceanica leaves. Compos. Part A Appl. Sci. Manuf. 2018, 112, 315–327.
  12. Scaffaro, R.; Maio, A.; Gulino, E.F.; Megna, B. Structure-property relationship of PLA-Opuntia Ficus Indica biocomposites. Compos. Part B Eng. 2019, 167, 199–206.
  13. Scaffaro, R.; Lopresti, F.; Botta, L.; Maio, A. Mechanical behavior of polylactic acid/polycaprolactone porous layered functional composites. Compos. Part B Eng. 2016, 98, 70–77.
  14. Scaffaro, R.; Botta, L.; Gallo, G. Photo-oxidative degradation of poly (ethylene-co-vinyl acetate)/nisin antimicrobial films. Polym. Degrad. Stab. 2012, 97, 653–660.
  15. Ferreira, A.R.V.; Torres, C.A.V.; Freitas, F.; Sevrin, C.; Grandfils, C.; Reis, M.A.M.; Alves, V.D.; Coelhoso, I.M. Development and characterization of bilayer films of FucoPol and chitosan. Carbohydr. Polym. 2016, 147, 8–15.
  16. Goh, K.; Heising, J.K.; Yuan, Y.; Karahan, H.E.; Wei, L.; Zhai, S.; Koh, J.X.; Htin, N.M.; Zhang, F.; Wang, R.; et al. Sandwich-architectured poly(lactic acid)-graphene composite food packaging films. ACS Appl. Mater. Interfaces 2016, 8, 9994–10004.
  17. Cerqueira, M.A.; Fabra, M.J.; Castro-Mayorga, J.L.; Bourbon, A.I.; Pastrana, L.M.; Vicente, A.A.; Lagaron, J.M. Use of electrospinning to develop antimicrobial biodegradable multilayer systems: Encapsulation of cinnamaldehyde and their physicochemical characterization. Food Bioprocess Technol. 2016, 9, 1874–1884.
  18. Sanyang, M.L.; Sapuan, S.M. Development of expert system for biobased polymer material selection: Food packaging application. J. Food Sci. Technol. 2015, 52, 6445–6454.
  19. Scaffaro, R.; Sutera, F.; Mistretta, M.C.; Botta, L.; Mantia, F.P. La Structure-properties relationships in melt reprocessed PLA/hydrotalcites nanocomposites. Express Polym. Lett. 2017, 11, 555–564.
  20. Scaffaro, R.; Lopresti, F.; Maio, A.; Sutera, F.; Botta, L. Development of polymeric functionally graded scaffolds: A brief review. J. Appl. Biomater. Funct. Mater. 2017, 15, 107–121.
  21. Farah, S.; Anderson, D.G.; Langer, R. Physical and mechanical properties of PLA, and their functions in widespread applications—A comprehensive review. Adv. Drug Deliv. Rev. 2016, 107, 367–392.
  22. Scaffaro, R.; Lopresti, F.; Botta, L.; Maio, A.; Sutera, F.; Mistretta, M.C.; La Mantia, F.P. A facile and eco-friendly route to fabricate poly(lactic acid) scaffolds with graded pore size. J. Vis. Exp. 2016, 2016.
  23. Gupta, A.; Simmons, W.; Schueneman, G.T.; Hylton, D.; Mintz, E.A. Rheological and thermo-mechanical properties of poly (lactic acid)/lignin-coated cellulose nanocrystal composites. ACS Sustain. Chem. Eng. 2017, 5, 1711–1720.
  24. Scaffaro, R.; Maio, A. Integrated ternary bionanocomposites with superior mechanical performance via the synergistic role of graphene and plasma treated carbon nanotubes. Compos. Part B Eng. 2019, 168, 550–559.
  25. Khalid, S.; Yu, L.; Feng, M.; Meng, L.; Bai, Y.; Ali, A.; Liu, H.; Chen, L. Development and characterization of biodegradable antimicrobial packaging films based on polycaprolactone, starch and pomegranate rind hybrids. Food Packag. Shelf Life 2018, 18, 71–79.
  26. Xing, Q.; Buono, P.; Ruch, D.; Dubois, P.; Wu, L.; Wang, W.-J. Biodegradable UV-blocking films through core--shell lignin--melanin nanoparticles in poly (butylene adipate-co-terephthalate). ACS Sustain. Chem. Eng. 2019, 7, 4147–4157.
  27. Witt, U.; Einig, T.; Yamamoto, M.; Kleeberg, I.; Deckwer, W.-D.; Müller, R.-J. Biodegradation of aliphatic--aromatic copolyesters: Evaluation of the final biodegradability and ecotoxicological impact of degradation intermediates. Chemosphere 2001, 44, 289–299.
  28. Re, G.L.; Morreale, M.; Scaffaro, R.; La Mantia, F.P. Biodegradation paths of Mater-Bi®/kenaf biodegradable composites. J. Appl. Polym. Sci. 2013, 129, 3198–3208.
  29. Scaffaro, R.; Morreale, M.; Lo Re, G.; La Mantia, F.P. Degradation of Mater-Bi®/wood flour biocomposites in active sewage sludge. Polym. Degrad. Stab. 2009, 94, 1220–1229.
  30. Lo Re, G.; Morreale, M.; Scaffaro, R.; La Mantia, F.P. Kenaf-filled biodegradable composites: Rheological and mechanical behaviour. Polym. Int. 2012, 61, 1542–1548.
  31. Alvarez, V.A.; Vázquez, A. Thermal degradation of cellulose derivatives/starch blends and sisal fibre biocomposites. Polym. Degrad. Stab. 2004, 84, 13–21.
  32. Scaffaro, R.; Morreale, M.; Lo Re, G.; La Mantia, F.P. Effect of the processing techniques on the properties of ecocomposites based on vegetable oil-derived Mater-Bi® and wood flour. J. Appl. Polym. Sci. 2009, 114, 2855–2863.
  33. Gregorová, A.; Riedl, E.; Sedlarik, V.; Stelzer, F. Effect of 4, 4′-methylenediphenyl diisocyanate on thermal and mechanical properties of Bioflex/lactic acid polycondensate blends. Asia-Pac. J. Chem. Eng. 2012, 7, S317–S323.
  34. Sedlarik, V.; Otgonzul, O.; Kitano, T.; Gregorova, A.; Hrabalova, M.; Junkar, I.; Cvelbar, U.; Mozetic, M.; Saha, P. Effect of phase arrangement on solid state mechanical and thermal properties of polyamide 6/polylactide based co-polyester blends. J. Macromol. Sci. Part B 2012, 51, 982–1001.
  35. Kucharczyk, P.; Otgonzu, O.; Kitano, T.; Gregorova, A.; Kreuh, D.; Cvelbar, U.; Sedlarik, V.; Saha, P. Correlation of morphology and viscoelastic properties of partially biodegradable polymer blends based on polyamide 6 and polylactide copolyester. Polym. Plast. Technol. Eng. 2012, 51, 1432–1442.
  36. La Mantia, F.P.; Ceraulo, M.; Mistretta, M.C.; Morreale, M. Effect of hot drawing on the mechanical properties of biodegradable fibers. J. Polym. Environ. 2016, 24, 56–63.
  37. La Mantia, F.P.; Ceraulo, M.; Mistretta, M.C.; Morreale, M. Rheological behaviour, mechanical properties and processability of biodegradable polymer systems for film blowing. J. Polym. Environ. 2018, 26, 749–755.
  38. Al-Itry, R.; Lamnawar, K.; Maazouz, A. Improvement of thermal stability, rheological and mechanical properties of PLA, PBAT and their blends by reactive extrusion with functionalized epoxy. Polym. Degrad. Stab. 2012, 97, 1898–1914.
  39. Woodruff, M.A.; Hutmacher, D.W. The return of a forgotten polymer—Polycaprolactone in the 21st century. Prog. Polym. Sci. 2010, 35, 1217–1256.
  40. Vert, M. Degradable and bioresorbable polymers in surgery and in pharmacology: Beliefs and facts. J. Mater. Sci. Mater. Med. 2009, 20, 437–446.
  41. Woodward, S.C.; Brewer, P.S.; Moatamed, F.; Schindler, A.; Pitt, C.G. The intracellular degradation of poly (epsilon-caprolactone). J. Biomed. Mater. Res. 1985, 19, 437–444.
  42. Yin, S.; Tuladhar, R.; Shi, F.; Shanks, R.A.; Combe, M.; Collister, T. Mechanical reprocessing of polyolefin waste: A review. Polym. Eng. Sci. 2015, 55, 2899–2909.
  43. Scaffaro, R.; Botta, L.; Di Benedetto, G. Physical properties of virgin-recycled ABS blends: Effect of post-consumer content and of reprocessing cycles. Eur. Polym. J. 2012, 48, 637–648.
  44. Luckachan, G.E.; Pillai, C.K.S. Biodegradable polymers-a review on recent trends and emerging perspectives. J. Polym. Environ. 2011, 19, 637–676.
  45. Dintcheva, N.T.; La Mantia, F.P.; Scaffaro, R.; Paci, M.; Acierno, D.; Camino, G. Reprocessing and restabilization of greenhouse films. Polym. Degrad. Stab. 2002, 75, 459–464.
  46. Badia, J.D.; Strömberg, E.; Karlsson, S.; Ribes-Greus, A. Material valorisation of amorphous polylactide. Influence of thermo-mechanical degradation on the morphology, segmental dynamics, thermal and mechanical performance. Polym. Degrad. Stab. 2012, 97, 670–678.
  47. Żenkiewicz, M.; Richert, J.; Rytlewski, P.; Moraczewski, K.; Stepczyńska, M.; Karasiewicz, T. Characterisation of multi-extruded poly (lactic acid). Polym. Test. 2009, 28, 412–418.
  48. Peinado, V.; Castell, P.; García, L.; Fernández, Á. Effect of extrusion on the mechanical and rheological properties of a reinforced poly (lactic acid): Reprocessing and recycling of biobased materials. Materials 2015, 8, 7106–7117.
  49. Scaffaro, R.; Morreale, M.; Mirabella, F.; La Mantia, F.P. Preparation and recycling of plasticized PLA. Macromol. Mater. Eng. 2011, 296.
  50. Morreale, M.; Liga, A.; Mistretta, M.; Ascione, L.; Mantia, F. Mechanical, thermomechanical and reprocessing behavior of green composites from biodegradable polymer and wood flour. Materials 2015, 8, 7536–7548.
  51. La Mantia, F.P.; Botta, L.; Morreale, M.; Scaffaro, R. Effect of small amounts of poly(lactic acid) on the recycling of poly(ethyleneterephtalate) bottles. Polym. Degrad. Stab. 2012, 97, 21–24.
  52. La Mantia, F.P.; Scaffaro, R.; Bastioli, C. Recycling of a starch-based biodegradable polymer. Macromol. Symp. 2002, 180, 133–140.
  53. Van de Velde, K.; Kiekens, P. Biopolymers: Overview of several properties and consequences on their applications. Polym. Test. 2002, 21, 433–442.
  54. Paola, S.; Luciano, D.M.; Loredana, I. Recent advances and migration issues in biodegradable polymers from renewable sources for food packaging. J. Appl. Polym. Sci. 2015, 132.
  55. Niaounakis, M. (Ed.) Biopolymers Reuse, Recycling, and Disposal; Plastics Design Library; William Andrew Publishing: Oxford, UK, 2013; ISBN 978-1-4557-3145-9.
  56. Badia, J.D.; Ribes-Greus, A. Mechanical recycling of polylactide, upgrading trends and combination of valorization techniques. Eur. Polym. J. 2016, 84, 22–39.
  57. Morreale, M.; Scaffaro, R.; Maio, A.; La Mantia, F.P. Effect of adding wood flour to the physical properties of a biodegradable polymer. Compos. Part A Appl. Sci. Manuf. 2008, 39, 503–513.
  58. Morreale, M.; Scaffaro, R.; Maio, A.; Mantia, F.P. La Mechanical behaviour of Mater-Bi®/wood flour composites: A statistical approach. Compos. Part A Appl. Sci. Manuf. 2008, 39, 1537–1546.
  59. Scaffaro, R.; Botta, L.; La Mantia, F.P. Preparation and Characterization of polyolefin-based nanocomposite blown films for agricultural applications. Macromol. Mater. Eng. 2009, 294, 445–454.
  60. Scaffaro, R.; Botta, L.; Mistretta, M.C.; La Mantia, F.P. Preparation and characterization of polyamide 6/polyethylene blend-clay nanocomposites in the presence of compatibilisers and stabilizing system. Polym. Degrad. Stab. 2010, 95, 2547–2554.
  61. Tesfaye, M.; Patwa, R.; Gupta, A.; Kashyap, M.J.; Katiyar, V. Recycling of poly (lactic acid)/silk based bionanocomposites films and its influence on thermal stability, crystallization kinetics, solution and melt rheology. Int. J. Biol. Macromol. 2017, 101, 580–594.
  62. Amorin, N.S.Q.S.; Rosa, G.; Alves, J.F.; Gonçalves, S.P.C.; Franchetti, S.M.M.; Fechine, G.J.M. Study of thermodegradation and thermostabilization of poly(lactide acid) using subsequent extrusion cycles. J. Appl. Polym. Sci. 2014, 131.
  63. Rojas-González, A.F.; Carrero-Mantilla, J.I. Cinética de degradación térmica de poliácido láctico en múltiples extrusiones. Ingenieria y Universidad 2015, 19, 189–206.
  64. Nascimento, L.; Gamez-Perez, J.; Santana, O.O.; Velasco, J.I.; Maspoch, M.L.; Franco-Urquiza, E. Effect of the recycling and annealing on the mechanical and fracture properties of poly(lactic acid). J. Polym. Environ. 2010, 18, 654–660.
  65. Zhou, Q.; Xanthos, M. Nanoclay and crystallinity effects on the hydrolytic degradation of polylactides. Polym. Degrad. Stab. 2008, 93, 1450–1459.
  66. Pandey, J.K.; Reddy, K.R.; Kumar, A.P.; Singh, R.P. An overview on the degradability of polymer nanocomposites. Polym. Degrad. Stab. 2005, 88, 234–250.
More
© Text is available under the terms and conditions of the Creative Commons Attribution (CC BY) license; additional terms may apply. By using this site, you agree to the Terms and Conditions and Privacy Policy.
Upload a video for this entry
Information
Subjects: Polymer Science
Contributor MDPI registered users' name will be linked to their SciProfiles pages. To register with us, please refer to https://encyclopedia.pub/register :
Marco Morreale
View Times: 841
Revisions: 2 times (View History)
Update Date: 17 Jan 2022
Table of Contents
    1000/1000
    Hot Most Recent
    Video Production Service
    Feedback