The mass production of polymer products, in particular plastics, and their widespread use depending on the inherent advantages they have, make these materials ironically a threat to life on Earth. Polymer recycling is being considered as one of the most widely accepted remedies to the threat of growing amounts of plastic waste by both the public and scientists. In practice, recycling is associated with many difficulties, such as problems related to separation, sorting and cleaning operations, lack of fiscal subsidies, instability of selective garbage separation programs, high transport and electricity costs, etc. Still, a large section of society and the authorities agree on the necessity and importance of recycling to protect the environment, and natural habitats and resources for future generations in a balanced manner to conserve raw materials, and to reduce energy consumption, municipal solid waste production and greenhouse gas emission. The recycling effort is almost endless in itself and includes a variety of approaches such as refurbishing, mechanically reshaping, chemically treating, thermally utilizing, etc. Some novel approaches such as application in carbon capture or synthesis of carbon nanostructures from the plastic waste are among the new process technologies of recycling. From traditional and promising polymer waste utilization approaches, this review will highlight sustainable methods to reduce impacts of plastic waste on the environment. © 2018 Society of Chemical Industry

Recent decades have seen great advancements in medical research into materials, both natural and synthetic, that facilitate the repair and regeneration of compromised tissues through the delivery and support of cells and/or biomolecules. Biocompatible polymeric materials have become the most heavily investigated materials used for such purposes. Naturally‐occurring and synthetic polymers, including their various composites and blends, have been successful in a range of medical applications, proving to be particularly suitable for tissue engineering (TE) approaches. The increasing advances in polymeric biomaterial research combined with the developments in manufacturing techniques have expanded capabilities in tissue engineering and other medical applications of these materials. This review will present an overview of the major classes of polymeric biomaterials, highlight their key properties, advantages, limitations and discuss their applications. © 2014 Society of Chemical Industry

Poly(glycerol-sebacate) (PGS) was introduced a decade ago as a potential material for soft tissue repair. All of the proposed copolymerization reactions in the literature include a two-stage ( prepolymerization and curing) synthesis where the reaction times can take as long as several days. This study, on the other hand, proposes a new route that eliminates these disadvantages and enables a rapid synthesis of PGS elastomers via microwave-assisted prepolymerization in minutes instead of days. No purge gas, catalyst or vacuum is needed in the first prepolymerization step. The curing stage was carried out at 150 °C for 4, 8, 16, and 24 hours. The glass transition temperature (T g ) and melting temperatures for the glycerol and sebacic acid fragments (T m 1 and T m 2 ) of these PGS elastomers were found as −35.61 °C, −15.82 °C, and 61.70 °C, respectively. The Young's modulus and tensile strength values were found as 0.50 ± 0.02 MPa and 0.27 ± 0.06 MPa, respectively.

Corneal tissue engineering efforts to obtain corneal tissue matrices through various types of materials for the replacement of damaged tissues. In this study, three different corneal constructs were prepared and evaluated in terms of morphological, optical, and biological characteristics. Type-I collagen was used to obtain collagen foam scaffolds through dehydrothermal crosslinking, while poly(l-lactic acid) (PLLA) was used to produce both random and aligned oriented electrospun corneal constructs. Bovine corneas were decellularized as third matrix. Software analyses showed that average pore size of collagen scaffolds was 88.207 ± 29.7 µm, while the average fiber diameter of aligned and random PLLA scaffolds were 0.69 ± 0.03 and 0.65 ± 0.03 μm, respectively. Degradation profiles revealed that collagen foam exhibits high degradation (20% mass loss) while electrospun PLLA scaffolds hold low degradation (9% mass loss) rates at day-28. Transmittance values of the obtained scaffolds were calculated as 92, 80, and 70% for collagen, PLLA, and decellularized cornea constructs, respectively. The evaluation of stromal keratocyte behavior on the constructs revealed that the cells exhibited their own morphology mostly on the aligned PLLA constructs, while they were mostly active on random PLLA electrospun corneal scaffolds. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 2157-2168, 2018.

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