


Sulfobetainic polymers were synthesized by polymeranalogous reaction of new amino celluloses starting from cellulose tosylate. To obtain different amino celluloses as starting building blocks, a comprehensive study with a selection of asymmetric and symmetric N-alkylated diamines was performed. For reaction with asymmetric diamines, it turned out that the primary amino moiety reacts preferably. Derivatives thus obtained consist in a neutral main structural unit and a cationic side structural unit, which is not described up to now. In order to investigate the reactivity of the amino celluloses 6-deoxy-6-(N,N,N′,N′-tetramethylethylenediamino) cellulose was used as uniform starting material for the design of novel polyampholytes by conversion with 1,3-propansultone. Detailed structure characterization was implemented by means of 1D and 2D-NMR spectroscopy.



Since recycling of polymers is a preferred means of reducing unwanted wastes and land-filling activity, and recovering monomers or other materials of economic value, tertiary methods of recycling (chemical recycling) have been critically reviewed, giving special attention, in each case, to the chemical basis of the particular recycling pathway and its potential applicability. Recycling issues of each of the widely used commodity polymers - polyesters, polyamides, polyurethanes, epoxies, poly (vinyl chloride), polycarbonate, and polyolefins – have been discussed individually, giving attention to both conventional and unconventional methods of perceived high potential, such as enzymatic degradation, ionic liquids mediation, microwave irradiation, and treatment in super critical liquids as well as super fluids. In addition, novel emerging methods undergoing greater study at present, such as cross-alkane metathesis (CAM), tandem hydrogenolysis/aromatization, vitrimer-based recycling, and dynamic covalent bonding are also highlighted.



Post-consumer plastic waste has reached levels that are dangerous for the environment and for human health, and its management now represents a big challenge. Plastic biodegradation and biorecycling emerges as an addition to the conventional plastic waste recycling methods. This review describes recent studies on enzyme-catalysed synthetic polymers biorecycling and biodegradation. The emphasize lies on the most successful cases as that of enzyme-catalysed depolymerisation of polyethylene terephthalate, using a specially engineered enzyme PET depolymerase, that has recently been developed into industrial technologies as well as on other recent promising discoveries of enzymes that are potentially capable of complete and controlled plastic degradation in mild conditions. The review also discusses polymer qualities that are causing diminished plastic biodegradation, and the protein engineering methods and tools to increase enzyme selectivity, activity and thermostability. Many fields of expertise have been used in the described studies, such as polymer chemistry, microbiology, mutagenesis, protein and process engineering. Applying this innovative interdisciplinary knowledge offers new perspectives for the environmental waste management and leads to a sustainable circular economy.



Replacing conventional plastics with bioplastics, i.e., plastics that are bioderived and/or biodegradable, does not necessarily solve the issues of resource depletion and plastic waste accumulation. To come to a truly sustainable plastics economy, the growing bioplastics production must be paralleled with effective end-of-life strategies for bioplastics waste, which is essential for all bioplastics, regardless of their biodegradability. While there is no doubt on the importance to recycle biobased non-biodegradable bioplastics such as bio-polyethylene terephthalate (bioPET), bio-polyethylene (bioPE), and bio-polypropylene (bioPP), the scenario is not as clear for biodegradable bioplastics, for which biodegradation is often seen as the only acceptable end-of-life option. However, biodegradation is normally not aimed at recovering plastic materials or monomers to be reintroduced in the life cycle of plastic products, while this is specifically the aim of other types of recycling options, such as mechanical and chemical recycling, which address both waste management and primary resource preservation. Hence, since bioplastics production is growing and such materials will coexist with conventional plastics for decades to come, it is vital to find the best end-of-life pathways for each of the most common bioplastics.



Recently, the demands for biodegradable and renewable materials for packaging applications have increased tremendously. This rise in demand is connected to the growing environmental concerns over the extensive use of synthetic and non-biodegradable polymeric packaging, polyethylene in particular. The performance of biodegradable polymers is discussed in this review, with a particular focus on the blends of starch and other polymers. Furthermore, in food packaging industry, microbial activities are of great concern. Therefore, incorporation of antimicrobial agents or polymers to produce barrier-enhanced or active packaging materials provides an attractive option for protecting food from microorganism development and spread. Additionally, the barrier, mechanical and other properties of biodegradable polymers are discussed. Lastly, the existing and potential applications for bioactive coatings on antimicrobial packaging materials are also addressed.



A significantly growing interest is to design new biodegradable polymers in order to solve fossil resources and environmental pollution problems associated with conventional plastics. A kind of new biodegradable polymers, aliphatic–aromatic co-polyesters have been researched widely and developed rapidly in recent years, since that can combine excellent biodegradability provided from aliphatic polyesters and good properties from aromatic polyesters. Out of which, poly (butylene-adipate-co-terephthalate) (PBAT) shows the most importance. PBAT has been commercialized by polycondensation reaction of butanediol (BDO), adipic acid (AA) and terephthalic acid (PTA) using general polyester manufacturing technology. And it has been considered to have desirable properties and competitive costs to be applied in many fields. Therefore, this review aims to present an overview on the synthesis, properties and applications of PBAT.