Environmental interaction of polymers-natural metabolites as opposed to the degradation products of synthetic polymers

AbstractThe degradation of synthetic polymers by marine microorganisms is not as well understood as the degradation of plastics in soil and compost. Here, we use metagenomics, metatranscriptomics and metaproteomics to study the biodegradation of an aromatic-aliphatic copolyester blend by a marine microbial enrichment culture. The culture can use the plastic film as the sole carbon source, reaching maximum conversion to CO2 and biomass in around 15 days. The consortium degrades the polymer synergistically, with different degradation steps being performed by different community members. We identify six putative PETase-like enzymes and four putative MHETase-like enzymes, with the potential to degrade aliphatic-aromatic polymers and their degradation products, respectively. Our results show that, although there are multiple genes and organisms with the potential to perform each degradation step, only a few are active during biodegradation.

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Recycling of Wastes Plastics and Tires from Automotive Industry

Polymers ◽

10.3390/polym13132210 ◽

2021 ◽

Vol 13 (13) ◽

pp. 2210

Author(s):

Iveta Čabalová ◽

Aleš Ház ◽

Jozef Krilek ◽

Tatiana Bubeníková ◽

Ján Melicherčík ◽

...

Keyword(s):

Automotive Industry ◽

Thermal Loading ◽

Degradation Products ◽

Calorific Value ◽

Synthetic Polymers ◽

Plastic Waste ◽

Analytical Pyrolysis ◽

Weight Loss Process ◽

And Calorimetry

Waste tires (granulate) and selected plastics from the automotive industry were evaluated by using the tertiary (pyrolysis) and quaternary (calorimetry) recovering. Pyrolysis is proving to be an environmentally friendly alternative to incineration and inefficient landfilling. Currently, the main challenges for pyrolysis of plastic waste are unavailability and inconsistent quality of feedstock, inefficient and hence costly sorting, and last but not least insufficient regulations around plastic waste management. Waste plastics and tire materials were characterized by TG/DTG analysis, Py-GC/MS analysis and calorimetry. TG analysis of the investigated materials gives the typical decomposition curves of synthetic polymers. The tested samples had the highest rate of weight loss process in the temperature range from 375 °C to 480 °C. Analytical pyrolysis of the tested polymers provided information on a wide variety of organic compounds that were released upon thermal loading of these materials without access to oxygen. Analytical pyrolysis offers valuable information on the spectrum of degradation products and their potential uses. Based on the results of calorimetry, it can be stated that the determined calorific value of selected plastic and rubber materials was ranging from 26.261 to 45.245 MJ/kg depending on the ash content and its composition.

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End-of-life upcycling of robust polyurethanes using a room temperature, mechanism-based degradation

10.21203/rs.3.rs-401646/v1 ◽

2021 ◽

Author(s):

Ephraim Morado ◽

Douglas Ivanoff ◽

Hsuan-Chin Wang ◽

Alayna Johnson ◽

Mara Paterson ◽

...

Keyword(s):

End Of Life ◽

Energy Input ◽

Room Temperature ◽

Degradation Products ◽

Polymeric Materials ◽

Synthetic Polymers ◽

Low Energy ◽

Waste Streams ◽

Rapid Degradation ◽

Oxocarbenium Ion

Abstract A major challenge in developing recyclable polymeric materials is the inherent conflict between the properties required during and after its life span. In particular, materials must be strong and durable when in use, but undergo complete and rapid degradation upon end-of-life. We report a new mechanism for degrading polyurethanes called CyclizAtion-Triggered CHain (CATCH) cleavage that achieves this duality. CATCH cleavage features a simple glycerol-based acyclic acetal unit as a kinetic and thermodynamic trap for gated chain-shattering. Thus, an organic acid induces transient chain breaks with oxocarbenium ion formation and subsequent intramolecular cyclization to depolymerize fully the polyurethane backbone at room temperature. With minimal chemical modification, the resulting degradation products can be repurposed into strong adhesives and photochromic coatings demonstrating the potential for upcycling. The CATCH cleavage strategy for low-energy input breakdown and subsequent upcycling may be generalizable to a broader range of synthetic polymers and their end-of-life waste streams.

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Potential of polyhydroxyalkanoate (PHA) polymers family as substitutes of petroleum based polymers for packaging applications and solutions brought by their composites to form barrier materials

Pure and Applied Chemistry ◽

10.1515/pac-2017-0401 ◽

2017 ◽

Vol 89 (12) ◽

pp. 1841-1848 ◽

Cited By ~ 20

Author(s):

Gülsah Keskin ◽

Gülnur Kızıl ◽

Mikhael Bechelany ◽

Céline Pochat-Bohatier ◽

Mualla Öner

Keyword(s):

Environmental Pollution ◽

Degradation Products ◽

Barrier Properties ◽

Synthetic Polymers ◽

Ecological Systems ◽

Short Term ◽

Gas Barrier ◽

Barrier Materials ◽

Potential Applications ◽

Gas Barrier Properties

Abstract Today, there is an increasing concern about protection of ecological systems. Petro-based synthetic polymers are not biodegradable and cause environmental pollution. These polymers that are stuck in nature, affect wildlife adversely. Also, in future petrochemical materials will drain away and demand for eco-friendly plastics which can substitute synthetic plastics will increase. Biopolymers are products which can be degraded by enzymatic activities of various microorganisms, and the degradation products are nontoxic. They are attractive alternatives to non-degradable materials in short-term applications such as packaging. Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) is a member of polyhydroxyalkanoate (PHA) family which is biodegradable and produced by microorganism. It has good gas barrier properties that make it convenient to use in different applications. The present paper gives an overview on PHAs and their composites, their main properties, with a specific focus on potential applications of PHBV in packaging.

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Synthetic Polymers for Organ 3D Printing

Polymers ◽

10.3390/polym12081765 ◽

2020 ◽

Vol 12 (8) ◽

pp. 1765

Author(s):

Fan Liu ◽

Xiaohong Wang

Keyword(s):

3D Printing ◽

Degradation Products ◽

Three Dimensional ◽

Synthetic Polymers ◽

Precise Control ◽

Chemical Structures ◽

Degradation Rates ◽

Organ Printing ◽

Printing Processes ◽

Controllable Degradation

Three-dimensional (3D) printing, known as the most promising approach for bioartificial organ manufacturing, has provided unprecedented versatility in delivering multi-functional cells along with other biomaterials with precise control of their locations in space. The constantly emerging 3D printing technologies are the integration results of biomaterials with other related techniques in biology, chemistry, physics, mechanics and medicine. Synthetic polymers have played a key role in supporting cellular and biomolecular (or bioactive agent) activities before, during and after the 3D printing processes. In particular, biodegradable synthetic polymers are preferable candidates for bioartificial organ manufacturing with excellent mechanical properties, tunable chemical structures, non-toxic degradation products and controllable degradation rates. In this review, we aim to cover the recent progress of synthetic polymers in organ 3D printing fields. It is structured as introducing the main approaches of 3D printing technologies, the important properties of 3D printable synthetic polymers, the successful models of bioartificial organ printing and the perspectives of synthetic polymers in vascularized and innervated organ 3D printing areas.

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Biological Response of Intramedullary Bone to Poly-L-Lactic Acid

MRS Proceedings ◽

10.1557/proc-252-339 ◽

1991 ◽

Vol 252 ◽

Cited By ~ 11

Author(s):

J. Suganuma ◽

H. Alexander ◽

J. Traub ◽

J. L. Ricci

Keyword(s):

Lactic Acid ◽

Fracture Fixation ◽

Degradation Products ◽

Biological Response ◽

Synthetic Polymers ◽

The Body ◽

Closed Space ◽

Fixation Devices ◽

Local Ph ◽

Internal Fracture

ABSTRACTBioabsorbable synthetic polymers have been studied for their possible application in absorbable internal fracture fixation devices. The current study examines the biological response of intramedullary bone to PLLA (poly-L-lactic acid). PLLA degrades at a rate sufficiently slow to be useful for fracture fixation and undergoes hydrolytic deesterification to form metabolites normally found in the body. Nevertheless, the lactic-acid-rich degradation products have the potential to significantly lower the local pH in a closed space surrounded by bone. It is hypothesized that this acidity may tend to cause abnormal bone resorption and/or demineralization.

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NEW BIOARTIFICIAL SYSTEMS AND BIODEGRADABLE SYNTHETIC POLYMERS FOR CARDIAC TISSUE ENGINEERING: A PRELIMINARY SCREENING

Biomedical Engineering Applications Basis and Communications ◽

10.4015/s1016237210002249 ◽

2010 ◽

Vol 22 (06) ◽

pp. 497-507 ◽

Cited By ~ 4

Author(s):

Elisabetta Rosellini ◽

Caterina Cristallini ◽

Niccoletta Barbani ◽

Giovanni Vozzi ◽

Mario D'Acunto ◽

...

Keyword(s):

Tissue Engineering ◽

Cardiac Tissue ◽

Degradation Products ◽

Synthetic Polymers ◽

Myocardial Tissue ◽

Specific Cell ◽

Biological Characterization ◽

Proliferation And Differentiation ◽

Poly Ethylene ◽

Myocardial Tissue Engineering

The aim of this work was the preparation and characterization of new polymeric biomaterials for application in myocardial tissue engineering. The attention was firstly focused on new bioartificial polymeric systems, with the aim to combine the features of synthetic polymers with the specific cell and tissue compatibility of biopolymers. In this work, alginate, collagen, and gelatin were used as the natural component and poly(N-isopropylacrylamide) was used as the synthetic component. The characterization included morphological, topographical, and mechanical analyses, thermogravimetric characterization, infrared spectroscopy, and cell culture tests. For the biological characterization, C2C12 myoblasts were cultured on different materials and cell adhesion, proliferation, and differentiation were evaluated. The morphological, topographical, and mechanical analyses, as well as the biological characterization, were also applied to a tri-block poly(ester-ether-ester) copolymer, obtained by reaction of preformed poly(ethylene glycol) with ε-caprolactone, and a novel poly(ester urethane) obtained by using an L-lisine-derived diisocyanate, giving nontoxic degradation products. The encouraging results obtained in this work allowed us to select some of the new bioartificial polymers, the synthetic tri-block copolymer, and the polyurethane as potential good materials to prepare scaffolds for myocardial tissue engineering.

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Extraction and identification of fillers and pigments from pyrolyzed rubber and tire samples

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100163332 ◽

1996 ◽

Vol 54 ◽

pp. 174-175

Author(s):

P. Sadhukhan ◽

J. B. Zimmerman

Keyword(s):

Zinc Oxide ◽

Electron Microscope ◽

Carbon Black ◽

Natural Rubber ◽

Transmission Electron Microscope ◽

Rolling Resistance ◽

Synthetic Polymers ◽

Nitrogen Atmosphere ◽

Transmission Electron ◽

Curing Agents

Rubber stocks, specially tires, are composed of natural rubber and synthetic polymers and also of several compounding ingredients, such as carbon black, silica, zinc oxide etc. These are generally mixed and vulcanized with additional curing agents, mainly organic in nature, to achieve certain “designing properties” including wear, traction, rolling resistance and handling of tires. Considerable importance is, therefore, attached both by the manufacturers and their competitors to be able to extract, identify and characterize various types of fillers and pigments. Several analytical procedures have been in use to extract, preferentially, these fillers and pigments and subsequently identify and characterize them under a transmission electron microscope.Rubber stocks and tire sections are subjected to heat under nitrogen atmosphere to 550°C for one hour and then cooled under nitrogen to remove polymers, leaving behind carbon black, silica and zinc oxide and 650°C to eliminate carbon blacks, leaving only silica and zinc oxide.

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