The effect of modification of sisal fibre with propionic anhydride and vinyltrimethoxy silane on the microbiological stability of poly(hydroxybutyrate-co-valerate) (PHBV) was investigated. The effect of the coupling agent - PHBV grafted with maleic anhydride (PHBV-g-MA) was also investigated. The best adhesion at the interface was observed for propionylation of sisal fibre, which improved the thermal properties of the composites. Composites with modified sisal fibre were characterized by higher activation energy (155 kJ/mol), which is related to stronger interactions at the matrix-fibre interface. In the microbial growth test, all biocomposites showed a decrease in molecular weight due to enzymatic degradation by Aspergillus niger. The most resistant to microorganisms was the composite containing propionylated sisal fibre. DMTA and TGA also confirmed the highest microbiological stability of the composite with the addition of propionylated sisal fibre, as evidenced by the smallest change in the properties after the microbiological growth test. In contrast, PHBV-g-MA caused significant enzymatic degradation due to the presence of large amorphous regions.

Multi-material multilayer plastic packaging (MMPP) is widely applied in fast moving consumer goods (FMCG) combining functionalities of distinct materials. These packaging structures can enhance properties, such as resource-use efficiency and barrier performance leading to consequential benefits like a prolonged shelf-life. Nevertheless, they represent a challenge for existing recycling systems, confronting circular economy principles. This study aim was to foresight the future of recycling technologies for MMPP in the next five to ten years. Future scenarios were identified, including (1) high-performance material recycling, (2) recycling into hydrocarbons, (3) business as usual, and (4) downcycling. In-depth interviews and a feedback survey were methods used to validate the scenario matrix while defining experts' expectations towards the future. The analysis showed that distinct technologies will develop unevenly in different parts of the world. A mix of all scenarios is probable in the upcoming years, depending, essentially, on regulations and technology availability. Advanced high-performance material recycling encounters systemic bottlenecks, such as insufficient sorting technology for post-consumer waste. In contrast, chemical recycling (feedstock) is concentrating investments as a solution, requiring low input-characterization. Additionally, design for recycling trends might reduce multilayers' complexity. A gap between recycling targets and recycling technologies was identified, representing short-term opportunities for more sustainable materials, such as bio-based.

This work was done to improve the interfacial adhesion and engineering performance of polyvinyl alcohol/polylactic acid laminate film by altering the polyvinyl alcohol phase surface properties via incorporating microfibrillated cellulose modified by propionylation. Incorporating the modified microfibrillated cellulose into polyvinyl alcohol film improved adhesion between film layers during the laminating process. Improved peel strength and tensile properties confirmed that modified microfibrillated cellulose can produce better bonding between polyvinyl alcohol and polylactic acid via mechanical interlocking and cohesive forces at the film interface. Modified microfibrillated cellulose (3 wt%) increased the peel strength by 40% comparing with the neat polyvinyl alcohol/polylactic acid laminate film.The reduction of both moisture absorption and diffusion rate of the modified microfibrillated cellulose–polyvinyl alcohol/polylactic acid to 20 and 23%, respectively, also indicated that the modified microfibrillated cellulose could inhibit moisture permeation across the film. This was because the modified microfibrillated cellulose is hydrophobic. Furthermore, the addition of modified microfibrillated cellulose also increased the decomposition temperature of the laminate film up to 10% as observed at 20% of remaining weight, while the storage modulus substantially increasing to 72% relative to the neat laminate film.The superior interfacial adhesion between the polylactic acid and modified microfibrillated cellulose–polyvinyl alcohol layers, observed by scanning electron microscopy, confirmed the improved compatibility between the polyvinyl alcohol and polylactic acid phases.

Detta bidrag beskriver och analyserar förberedelsefasen inför implementeringen av ett högskolepedagogiskt excellensprogram vid Kungliga Tekniska Högskolan, KTH. Programmet syftar till att ytterligare stärka värdet av pedagogiska meriter och samtidigt bidra till lärosätets fortsatta och fördjupade utveckling av utbildningarna och organisationen. De tydligaste riskerna som har identifierats med befintliga pedagogiska meriteringsmodeller är att de kan skapa ett A- och B-lag (mellan en karriär som forskare och en karriär som lärare). Dessutom är det ofta oklart hur personer som har utnämnts till excellenta lärare ska kunna bidra till organisationens och utbildningens utveckling ur ett kortsiktigt såväl som ett långsiktigt perspektiv. En tydlig svaghet med befintliga pedagogiska meriteringsmodeller är att de inte explicit nog ger emfas till aktivt och relevant utvecklingsarbete, utan fokuserar på egenhändigt skrivna pedagogiska portföljer som sällan är framtidsinriktade. KTH:s högskolepedagogiska excellensprogram siktar på att försöka möta dessa risker och svagheter. KTH har, alltjämt sedan det nationella obligatoriet om 15 hp Högskolepedagogik infördes, kvarhållit detta obligatorium. Stora satsningar har gjorts på den högskolepedagogiska verksamheten. Ett gediget utbud av fortbildningsmöjligheter samt arenor för nätverkande har utvecklats. Samtidigt råder svagheter i systemet gällande prövande och tillvaratagande av pedagogisk skicklighet, och det är tydligt att KTH behöver ytterligare utveckling i området. Författarna menar också att i och med att de utmaningar vi står inför gällande pedagogisk meritering ser relativt lika ut vid landets lärosäten, bör ett stärkt nationellt samarbete och nätverkande inom landets ingenjörsutbildningar främjas inom området. Artikelförfattarna representerar KTH:s övergripande ledning, utbildningsledning samt ledningen för den högskolepedagogiska verksamheten.

Lignocellulosic biocomposite is a promising biodegradable materials, though improvement of the interfacial adhesion between cellulose fibre and polymer matrix is still challenged. Therefore, this work investigated the effect of propionylation of sisal reinforced fibre in the sisal/polyhydroxybutyrate-co-valerate (PHBV) biocomposite. Propionylation involved esterification substitution of propionic anhydride to hydroxyl group of sisal fibre, where ester group (COOR) of propionylated fibre was successfully observed by Fourier transform Infrared spectroscopy (FTIR). Then mechanical and thermal properties were evaluated and biodegradation characteristics were assessed. The tensile strength and modulus of propionylated sisal/PHBV biocomposite were greater than unmodified sisal/PHBV, which revealed better compatibility at the interface. In addition, propionate moieties of sisal fibre could induce crystalline formation of PHBV, as determined by an increase of crystalline phase. The higher decomposition temperature (Td) and activation energy (Ea) of 155 kJ.mol(-1), determined by thermal gravimetric analyser (TGA), were strong confirmation of good thermal resistance of the propionylated sisal biocomposite. The storage modulus, as characterized by dynamic mechanical thermal analyser (DMTA), also revealed the improvement of stiffness. Bacterial growth tests evaluated the inhibition of bacterial growth on the PHBV biocomposites. It was clear that propionylation of sisal fibre decreased colonization of Staphylococcus aureus (SA) and Escherichia coli (E.coli).