Multi-material plastic waste streams can now be thoroughly sorted by means of automated methods, and fractions consisting of different chemical classes (e. g. polyesters, polyamides, polyurethanes etc) are obtained in (close to) mono-material form. A most notable exception are polyolefins (PO), namely polyethylene (PE) and polypropylene (PP). Polyolefins are synthetic organic macromolecules that constitutes the largest segment of the plastic market. These materials are everywhere, from packaging to toys and life-saving medical innovations, thereby accounting for more than half of global polymer production and waste. Indeed, the vast majority of polyolefins are fabricated for performance, not for durability and recyclability and if plastic demand follows its current trajectory, the global waste volumes would grow from 260 million tons per year in 2016 to 460 million tons per year in 2030 with a catastrophic impact on the environment. Effective strategies to improve the value-chain of polyolefins and to keep them within the circular economy are mandatory.
PO are also poorly amenable to thermal recycling, due to an exceedingly high chemical stability, whereas mechanical recycling is complicated by the thermodynamic incompatibility of PE and PP. Indeed, the greatest challenge in recycling commingled plastic waste is that most plastics are immiscible with one another, producing phase-separated mixture and fragile interfaces which results in poor mechanical properties (immiscible PO blends have poor application properties). Roughly 5% of the economic value is retained when plastic wastes are recycled. The CORE idea to overcome this limitation is the development an efficient mechanical recycling strategy based on the use of phase compatibilizers (PC) able to control the phase behaviour of polymer mixtures, opening the opportunities for up-cycling without pre-sorting. Phase compatibilizers are multicomponent random or block copolymers, with controlled architecture, presenting tailored thermodynamic interactions with the immiscible polymers in the mixture.
Compatibilizers arrange at the interfaces between the two components of the blend and help to modify the sharp and mechanically weak interfaces. This leads to a system characterized by a fine phase structure with enhanced interfacial adhesion and improved the final mechanical properties (up-cycling).
CORE presents an interdisciplinary research project at the crossover of the different technological areas including: i) design and synthesis of further improved PC structures, ii) development of fast analysis and formulation methods, iii)study of structure-property relationships of compatibilized blends, iiii) study of the effect of mechanical recycling processes on the processability, rheological characteristics, microstructure, mechanical and physico-chemical properties of recycled polymers etc.
The goal is to make more easily recyclable and reusable polyolefin blends for application in furniture and packaging components.<\/p>\n","protected":false},"parent":0,"template":"","class_list":["post-1863","projects","type-projects","status-publish","hentry"],"acf":[],"yoast_head":"\n