Friction is a genuine issue in the use of many medical devices involving rubbery materials such as plungers in medical syringes. This paper presents a new direction for the reduction of friction in medical syringes ba...Friction is a genuine issue in the use of many medical devices involving rubbery materials such as plungers in medical syringes. This paper presents a new direction for the reduction of friction in medical syringes based on surface texturing of the rubber plunger. The specimens were prepared by casting poly(vinylsiloxane)(PVS) rubber into a pre-fabricated negative template obtained by 3D printing. Friction tests were performed on a home-made test-rig. It was clearly shown that friction resistance can be considerably manipulated when using textured plungers.展开更多
The surge in medical waste,fueled by the impact of COVID-19 and the influenza A virus,poses substantial challenges to waste treatment.Nevertheless,pyrolysis technology introduces a novel approach to the treatment of m...The surge in medical waste,fueled by the impact of COVID-19 and the influenza A virus,poses substantial challenges to waste treatment.Nevertheless,pyrolysis technology introduces a novel approach to the treatment of medical waste.This study investigated the pyrolytic characteristics,kinetics,thermodynamic parameters,volatile gases,and pyrolytic pathways of medical rubber gloves(MRGs)in a N2 atmosphere utilizing Thermal Gravimetric Analyzer(TGA),Thermogravimetric-Fourier transform infrared spectroscopy(TG-FTIR)and Pyrolysis gas chrogams-mass spectrometry(Py-GC/MS)analyses.Pyrolysis of MRG predominantly occurs between 284-501℃ and 613-701℃.The initial stage is the primary reaction phase,exhibiting an average activation energy of 339.77 kJ/mol,following the reaction order model(Fn).The second pyrolysis stage has an average activation energy of 236.93 kJ/mol and adheres to the geometric contraction model(Rn).The volatile products from MRG pyrolysis primarily comprise olefins,alkanes,and aromatic hydrocarbons.The olefins consist primarily of 1,2-pentadiene and D-limonene,while the alkanes include cyclopropane,cyclohexane,and 1,4-dimethyl.Aromatic compounds are chiefly benzene,toluene,and xylene.展开更多
Thermogravimetric study of rubber compositions （operating glove and catheter） in medical waste was carried out using the thermogravimetric analyser （TGA）,at the heating rate of 20 ℃/min in a stream of N2.The resu...Thermogravimetric study of rubber compositions （operating glove and catheter） in medical waste was carried out using the thermogravimetric analyser （TGA）,at the heating rate of 20 ℃/min in a stream of N2.The results indicate that the decomposition process of operating glove appears an obvious mass loss stage at 250-485 ℃,while catheter has two obvious stages at 240-510 ℃ and 655-800 ℃,respectively; both samples present endothermic pyrolysis reaction; the decomposition of operating glove and the first mass loss stage of catheter are in agreement with natural rubber pyrolysis; the second mass loss stage of catheter corresponds to CaCO3 decomposition.Based on the experimental results,a novel two-step four-reaction model was established to simulate the whole continuous processes,which could more satisfactorily describe and predict the pyrolysis processes of rubber compositions,being more mechanistic and conveniently serving for the engineering.展开更多
基金funded by Maof Fellowships, the Council for Higher Education of Israel (Dr. H. Kasem)the MIA program the Ministry of Science, Technology & Space (Prof. A. Domb)
文摘Friction is a genuine issue in the use of many medical devices involving rubbery materials such as plungers in medical syringes. This paper presents a new direction for the reduction of friction in medical syringes based on surface texturing of the rubber plunger. The specimens were prepared by casting poly(vinylsiloxane)(PVS) rubber into a pre-fabricated negative template obtained by 3D printing. Friction tests were performed on a home-made test-rig. It was clearly shown that friction resistance can be considerably manipulated when using textured plungers.
基金financially supported by the LiaoNing Revitalization Talents Program(No.XLYC2008013)National Natural Science Foundation(No.U21A20142).
文摘The surge in medical waste,fueled by the impact of COVID-19 and the influenza A virus,poses substantial challenges to waste treatment.Nevertheless,pyrolysis technology introduces a novel approach to the treatment of medical waste.This study investigated the pyrolytic characteristics,kinetics,thermodynamic parameters,volatile gases,and pyrolytic pathways of medical rubber gloves(MRGs)in a N2 atmosphere utilizing Thermal Gravimetric Analyzer(TGA),Thermogravimetric-Fourier transform infrared spectroscopy(TG-FTIR)and Pyrolysis gas chrogams-mass spectrometry(Py-GC/MS)analyses.Pyrolysis of MRG predominantly occurs between 284-501℃ and 613-701℃.The initial stage is the primary reaction phase,exhibiting an average activation energy of 339.77 kJ/mol,following the reaction order model(Fn).The second pyrolysis stage has an average activation energy of 236.93 kJ/mol and adheres to the geometric contraction model(Rn).The volatile products from MRG pyrolysis primarily comprise olefins,alkanes,and aromatic hydrocarbons.The olefins consist primarily of 1,2-pentadiene and D-limonene,while the alkanes include cyclopropane,cyclohexane,and 1,4-dimethyl.Aromatic compounds are chiefly benzene,toluene,and xylene.
基金Project(50378062)supported by the National Natural Science Foundation of ChinaProject(09JCYBJC08100)supported by the Natural Science Foundation of Tianjin Municipality,ChinaProject supported by Key Laboratory Program of the Ministry of Education,China
文摘Thermogravimetric study of rubber compositions （operating glove and catheter） in medical waste was carried out using the thermogravimetric analyser （TGA）,at the heating rate of 20 ℃/min in a stream of N2.The results indicate that the decomposition process of operating glove appears an obvious mass loss stage at 250-485 ℃,while catheter has two obvious stages at 240-510 ℃ and 655-800 ℃,respectively; both samples present endothermic pyrolysis reaction; the decomposition of operating glove and the first mass loss stage of catheter are in agreement with natural rubber pyrolysis; the second mass loss stage of catheter corresponds to CaCO3 decomposition.Based on the experimental results,a novel two-step four-reaction model was established to simulate the whole continuous processes,which could more satisfactorily describe and predict the pyrolysis processes of rubber compositions,being more mechanistic and conveniently serving for the engineering.
