Conventional bioplastic production from seaweed often relies on extraction processes that are costly,time-consuming,and yield limited product.This study presents a direct fabrication method using Gracilaria sp.,a red ...Conventional bioplastic production from seaweed often relies on extraction processes that are costly,time-consuming,and yield limited product.This study presents a direct fabrication method using Gracilaria sp.,a red seaweed rich in polysaccharides,to produce bioplastic films without the need for extraction.Sorbitol was incorporated as a plasticizer at concentrations of 0%–10%(w/w)to modify film characteristics.Thermal analysis revealed improved stability at moderate sorbitol levels(5%–7%),while excessive plasticizer slightly reduced thermal resistance.Mechanical testing showed that sorbitol increased film flexibility and elongation at break,though tensile strength and stiffness declined.Tear strength followed a non-linear trend,with improvement observed at higher sorbitol concentrations.Seal strength also increased,peaking at 7%,indicating stronger interfacial bonding between film layers.Biodegradation tests demonstrated accelerated decomposition with increased sorbitol content,achieving complete degradation within 30 days at 10% concentration.Color analysis showed increased brightness and reduced yellowing,enhancing the visual quality of the films.These results confirm that direct conversion of bioplastic is both feasible and effective.Sorbitol plays a key role in tuning film properties,offering a low-cost,scalable pathway to biodegradable materials suitable for environmentally friendly packaging applications.展开更多
Although poly(lactic acid)(PLA)is a good environmentally-friendly bio-degradable polymer which is used to substitute traditional petrochemical-based polymer packaging films,the barrier properties of PLA films are stil...Although poly(lactic acid)(PLA)is a good environmentally-friendly bio-degradable polymer which is used to substitute traditional petrochemical-based polymer packaging films,the barrier properties of PLA films are still insufficient for high-barrier packaging applications.In this study,oxygen scavenger hydroxyl-terminated polybutadiene(HTPB)and cobalt salt catalyst were incorporated into the PLA/poly(butylene adipate-co-terephthalate)(PLA/PBAT),followed by melting extrusion and three-layer co-extrusion blown film process to prepare the composite films.The oxygen permeability coefficient of the composite film combined with 6 wt%oxygen scavenger and 0.4 wt%catalyst was decreased significantly from 377.00 cc·mil·m^(-2)·day^(-1)·0.1 MPa^(-1) to 0.98 cc·mil·m^(-2)·day^(-1)·0.1 MPa^(-1),showing a remarkable enhancement of 384.69 times compared with the PLA/PBAT composite film.Meanwhile,the degradation behavior of the composite film was also accelerated,exhibiting a mass loss of nearly 60%of the original mass after seven days of degradation in an alkaline environment,whereas PLA/PBAT composite film only showed a mass loss of 32%.This work has successfully prepared PLA/PBAT composite films with simultaneously improved oxygen barrier property and degradation behavior,which has great potential for high-demanding green chemistry packaging industries,including food,agricultural,and military packaging.展开更多
基金funded by IAEA Coordinated Research Project F22081.
文摘Conventional bioplastic production from seaweed often relies on extraction processes that are costly,time-consuming,and yield limited product.This study presents a direct fabrication method using Gracilaria sp.,a red seaweed rich in polysaccharides,to produce bioplastic films without the need for extraction.Sorbitol was incorporated as a plasticizer at concentrations of 0%–10%(w/w)to modify film characteristics.Thermal analysis revealed improved stability at moderate sorbitol levels(5%–7%),while excessive plasticizer slightly reduced thermal resistance.Mechanical testing showed that sorbitol increased film flexibility and elongation at break,though tensile strength and stiffness declined.Tear strength followed a non-linear trend,with improvement observed at higher sorbitol concentrations.Seal strength also increased,peaking at 7%,indicating stronger interfacial bonding between film layers.Biodegradation tests demonstrated accelerated decomposition with increased sorbitol content,achieving complete degradation within 30 days at 10% concentration.Color analysis showed increased brightness and reduced yellowing,enhancing the visual quality of the films.These results confirm that direct conversion of bioplastic is both feasible and effective.Sorbitol plays a key role in tuning film properties,offering a low-cost,scalable pathway to biodegradable materials suitable for environmentally friendly packaging applications.
基金financial support of this work by the National Natural Science Foundation of China(Nos.22378332,52003219)the Open Fund of Zhejiang Key Laboratory of Flexible Electronics(No.2022FE008)+1 种基金the Natural Science Foundation of Ningbo(NO.2022J058)Ministry of Industry and Information Technology high quality development project(TC220A04A-206).
文摘Although poly(lactic acid)(PLA)is a good environmentally-friendly bio-degradable polymer which is used to substitute traditional petrochemical-based polymer packaging films,the barrier properties of PLA films are still insufficient for high-barrier packaging applications.In this study,oxygen scavenger hydroxyl-terminated polybutadiene(HTPB)and cobalt salt catalyst were incorporated into the PLA/poly(butylene adipate-co-terephthalate)(PLA/PBAT),followed by melting extrusion and three-layer co-extrusion blown film process to prepare the composite films.The oxygen permeability coefficient of the composite film combined with 6 wt%oxygen scavenger and 0.4 wt%catalyst was decreased significantly from 377.00 cc·mil·m^(-2)·day^(-1)·0.1 MPa^(-1) to 0.98 cc·mil·m^(-2)·day^(-1)·0.1 MPa^(-1),showing a remarkable enhancement of 384.69 times compared with the PLA/PBAT composite film.Meanwhile,the degradation behavior of the composite film was also accelerated,exhibiting a mass loss of nearly 60%of the original mass after seven days of degradation in an alkaline environment,whereas PLA/PBAT composite film only showed a mass loss of 32%.This work has successfully prepared PLA/PBAT composite films with simultaneously improved oxygen barrier property and degradation behavior,which has great potential for high-demanding green chemistry packaging industries,including food,agricultural,and military packaging.
