Crosslinked poly(vinyl alcohol)(PVA)based composite films were prepared as polyelectrolyte membranes for low temperature direct ethanol fuel cells(DEFC).The membranes were functionalised by means of the addition of gr...Crosslinked poly(vinyl alcohol)(PVA)based composite films were prepared as polyelectrolyte membranes for low temperature direct ethanol fuel cells(DEFC).The membranes were functionalised by means of the addition of graphene oxide(GO)and sulfonated graphene oxide(SGO)and crosslinked with sulfosuccinic acid(SSA).The chemical structure was corroborated and suitable thermal properties were found.Although the addition of GO and SGO slightly decreased the proton conductivity of the membranes,a significant reduction of the ethanol solution swelling and crossover was encountered,more relevant for those functionalised with SGO.In general,the composite membranes were stable under simulated service conditions.The addition of GO and SGO particles permitted to buffer the loss and almost retain similar proton conductivity than prior to immersion.These membranes are alternative polyelectrolytes,which overcome current concerns of actual commercial membranes such as the high cost or the crossover phenomenon.展开更多
A blending strategy of virgin and reprocessed polylactide may be postulated as an alternative to reduce the material cost at industrial level,and as a valorization route to plastic waste management of production scrap...A blending strategy of virgin and reprocessed polylactide may be postulated as an alternative to reduce the material cost at industrial level,and as a valorization route to plastic waste management of production scraps.The performance of blends prepared from virgin polylactide and polylactide mechanically reprocessed up to two cycles(PLA-V/R)was assessed in terms of thermo-oxidative stability,morphology,viscoelasticity and thermal kinetics for energetic valorization.PLA-V/R blends showed appropriate thermo-oxidative stability.The amorphous nature of polylactide was preserved after blending.The viscoelastic properties showed an increment of the mechanical blend effectiveness,which suggested the feasibility of using PLA-V/R blends under similar mechanical conditions to those of virgin PLA goods.Finally,it was shown that the energetic valorization of PLA-V/R blends would result in a more feasible process,due to the lower required activation energy,thus highlighting the advantages of the energetic demand for the process.In conclusion,PLA-V/R blends showed similar processability,service performance and valorization routes as virgin PLA and therefore could be relevant in the sustainable circular industry of bioplastics.展开更多
Composite polymer electrolyte membranes were prepared with poly(vinyl alcohol)(PVA).Two different molecular weight(Mw),67·103 and 130·103 g·mol−1 were selected,cross-linked with sulfosuccinic acid(SSA)a...Composite polymer electrolyte membranes were prepared with poly(vinyl alcohol)(PVA).Two different molecular weight(Mw),67·103 and 130·103 g·mol−1 were selected,cross-linked with sulfosuccinic acid(SSA)and doped graphene oxide(GO).The effects on the membranes obtained from these polymers were characterized in order to evaluate the fuel cell performance.Electron microscopy showed a proper nanoparticle distribution in the polymer matrix.The chemical structure was evaluated by Fourier transform infrared spectroscopy.The absence of a crystalline structure and the enhancement on the thermal stability with the addition of 1%of GO was demonstrated by thermal characterization.Total transference number and protonic conductivity were correlated to the performance of a hydrogen fuel cell.Overall,a power increase in the composite membranes with lower molecular weight was observed.Shorter polymer chains may improve protonic conductivity and consequently the fuel cell performance.展开更多
基金the support of the European Union through the European Regional Development Funds(ERDF)The Spanish Ministry of Economy,Industry and Competitiveness,is thanked for the research project POLYDECARBOCELL(ENE2017-86711-C3-1-R)The Spanish Ministry of Education,Culture and Sports is thanked for the FPU grant for O.Gil-Castell(FPU13/01916)。
文摘Crosslinked poly(vinyl alcohol)(PVA)based composite films were prepared as polyelectrolyte membranes for low temperature direct ethanol fuel cells(DEFC).The membranes were functionalised by means of the addition of graphene oxide(GO)and sulfonated graphene oxide(SGO)and crosslinked with sulfosuccinic acid(SSA).The chemical structure was corroborated and suitable thermal properties were found.Although the addition of GO and SGO slightly decreased the proton conductivity of the membranes,a significant reduction of the ethanol solution swelling and crossover was encountered,more relevant for those functionalised with SGO.In general,the composite membranes were stable under simulated service conditions.The addition of GO and SGO particles permitted to buffer the loss and almost retain similar proton conductivity than prior to immersion.These membranes are alternative polyelectrolytes,which overcome current concerns of actual commercial membranes such as the high cost or the crossover phenomenon.
文摘A blending strategy of virgin and reprocessed polylactide may be postulated as an alternative to reduce the material cost at industrial level,and as a valorization route to plastic waste management of production scraps.The performance of blends prepared from virgin polylactide and polylactide mechanically reprocessed up to two cycles(PLA-V/R)was assessed in terms of thermo-oxidative stability,morphology,viscoelasticity and thermal kinetics for energetic valorization.PLA-V/R blends showed appropriate thermo-oxidative stability.The amorphous nature of polylactide was preserved after blending.The viscoelastic properties showed an increment of the mechanical blend effectiveness,which suggested the feasibility of using PLA-V/R blends under similar mechanical conditions to those of virgin PLA goods.Finally,it was shown that the energetic valorization of PLA-V/R blends would result in a more feasible process,due to the lower required activation energy,thus highlighting the advantages of the energetic demand for the process.In conclusion,PLA-V/R blends showed similar processability,service performance and valorization routes as virgin PLA and therefore could be relevant in the sustainable circular industry of bioplastics.
基金funded by the Spanish Ministry of Economy,Industry and Competitiveness,through the research project POLYDECARBOCELL(ENE2017-86711-C3-1-R)by the Spanish Ministry of Education,Culture and Sports through the FPU grant for O.Gil-Castell(FPU13/01916).
文摘Composite polymer electrolyte membranes were prepared with poly(vinyl alcohol)(PVA).Two different molecular weight(Mw),67·103 and 130·103 g·mol−1 were selected,cross-linked with sulfosuccinic acid(SSA)and doped graphene oxide(GO).The effects on the membranes obtained from these polymers were characterized in order to evaluate the fuel cell performance.Electron microscopy showed a proper nanoparticle distribution in the polymer matrix.The chemical structure was evaluated by Fourier transform infrared spectroscopy.The absence of a crystalline structure and the enhancement on the thermal stability with the addition of 1%of GO was demonstrated by thermal characterization.Total transference number and protonic conductivity were correlated to the performance of a hydrogen fuel cell.Overall,a power increase in the composite membranes with lower molecular weight was observed.Shorter polymer chains may improve protonic conductivity and consequently the fuel cell performance.