Melt blending of biodegradable polyesters such as poly(lactic acid)(PLA)and poly(butylene adipate co-terephthalate)(PBAT)with a compatibilizer and natural filler offers a chance to develop biodegradable biocomposites ...Melt blending of biodegradable polyesters such as poly(lactic acid)(PLA)and poly(butylene adipate co-terephthalate)(PBAT)with a compatibilizer and natural filler offers a chance to develop biodegradable biocomposites with improved performance.In this study,we examined how PLA/PBAT blends behave during ultimate biodegradation(mineralization),both with and without compatibilizer and algae as a reinforcement,under controlled composting conditions using carbon dioxide(CO_(2))respirometry techniques.Throughout the biodegradation process,the disintegration behaviour,thermal,chemical,and morphological properties of test samples before and after biodegradation were analyzed using FTIR,TGA,DSC,and SEM techniques.The results from CO_(2)biodegradation showed that PLA/PBAT blend exhibits a higher rate of biodegradation compared to neat PLA and PBAT.The addition of algae to a compatibilized PLA/PBAT blend showed an enhanced biodegradation rate due to hydrolytic cleavage and microbial assimilation.This was further supported by the disintegration test,where algae-reinforced composites showed fragmentation within 30 days.FTIR,TGA and SEM analysis revealed the structural changes that occurred during biodegradation,highlighting the role of algae in affecting the thermal stability and surface morphology.After the compost biodegradation step,eco-toxicity seed germination was conducted on the test samples.Plant seed germination test results confirmed that all test samples achieved maximumgermination.This indicates there were no toxic residues,suggesting that the degraded materials are environmentally safe.Overall,this study contributes to the understanding of biodegradation mechanisms and the ecological impact of bio-based polymer composites as eco-friendly materials and products.展开更多
Biodegradable triblock copolymer PLA/PEG/PLA was synthesized by ring-opening bulk polymerization of D,L-lactide in the presence of poly(ethylene glycol) (PEG), in the molecular structure of which, the length of PEG an...Biodegradable triblock copolymer PLA/PEG/PLA was synthesized by ring-opening bulk polymerization of D,L-lactide in the presence of poly(ethylene glycol) (PEG), in the molecular structure of which, the length of PEG and PLA chain segments was made to be quite different. Nanoparticles were prepared by using the copolymer via a double emulsion-evaporation technique. The paticles tended to form the configuration like capsules, i.e., the nanocapsules, because of the great size difference in PEG and PLA segments of the copolymer. Insulin, chosen as a model drug, was encapsulated into nanocapsules. The effect of preparation conditions on the size, insulin encapsulation efficiency, and in vitro drug release behavour of the nanoparticles were investigated. The experimental results show that the nanocapsules had a smooth spherical surface and the mean diameter was in the range from 180 nm to 350 nm, and the entrapment of insulin achieved up to 78.4. The drug-loaded nanocapsules released their content continuously, remarkably different from the corresponding micelles which gave a significant initial burst release followed by a slow release.展开更多
文摘Melt blending of biodegradable polyesters such as poly(lactic acid)(PLA)and poly(butylene adipate co-terephthalate)(PBAT)with a compatibilizer and natural filler offers a chance to develop biodegradable biocomposites with improved performance.In this study,we examined how PLA/PBAT blends behave during ultimate biodegradation(mineralization),both with and without compatibilizer and algae as a reinforcement,under controlled composting conditions using carbon dioxide(CO_(2))respirometry techniques.Throughout the biodegradation process,the disintegration behaviour,thermal,chemical,and morphological properties of test samples before and after biodegradation were analyzed using FTIR,TGA,DSC,and SEM techniques.The results from CO_(2)biodegradation showed that PLA/PBAT blend exhibits a higher rate of biodegradation compared to neat PLA and PBAT.The addition of algae to a compatibilized PLA/PBAT blend showed an enhanced biodegradation rate due to hydrolytic cleavage and microbial assimilation.This was further supported by the disintegration test,where algae-reinforced composites showed fragmentation within 30 days.FTIR,TGA and SEM analysis revealed the structural changes that occurred during biodegradation,highlighting the role of algae in affecting the thermal stability and surface morphology.After the compost biodegradation step,eco-toxicity seed germination was conducted on the test samples.Plant seed germination test results confirmed that all test samples achieved maximumgermination.This indicates there were no toxic residues,suggesting that the degraded materials are environmentally safe.Overall,this study contributes to the understanding of biodegradation mechanisms and the ecological impact of bio-based polymer composites as eco-friendly materials and products.
文摘Biodegradable triblock copolymer PLA/PEG/PLA was synthesized by ring-opening bulk polymerization of D,L-lactide in the presence of poly(ethylene glycol) (PEG), in the molecular structure of which, the length of PEG and PLA chain segments was made to be quite different. Nanoparticles were prepared by using the copolymer via a double emulsion-evaporation technique. The paticles tended to form the configuration like capsules, i.e., the nanocapsules, because of the great size difference in PEG and PLA segments of the copolymer. Insulin, chosen as a model drug, was encapsulated into nanocapsules. The effect of preparation conditions on the size, insulin encapsulation efficiency, and in vitro drug release behavour of the nanoparticles were investigated. The experimental results show that the nanocapsules had a smooth spherical surface and the mean diameter was in the range from 180 nm to 350 nm, and the entrapment of insulin achieved up to 78.4. The drug-loaded nanocapsules released their content continuously, remarkably different from the corresponding micelles which gave a significant initial burst release followed by a slow release.
