The catalytic effects of the organic compounds of iron,tin and manganese on the degradation of low density polyethylene (LDPE) at compost temperature are discussed.A series of samples were aged in a simulating compost...The catalytic effects of the organic compounds of iron,tin and manganese on the degradation of low density polyethylene (LDPE) at compost temperature are discussed.A series of samples were aged in a simulating compost environment.The mechanical properties,viscosity average molecular weight (M η) of PE and hydroperoxide (POOH) concentration in the samples were measured.FT IR and DSC were also applied to characterize some samples.It was shown that the above mentioned metallic organic compounds can catalyze the degradation of LDPE efficiently.After 2 months aging,all samples with catalysts became fragile and the M η of the material decreased dramatically.Furthermore,the concentration of carbonyl and the degree of crystallinity of the material increased with the aging time.展开更多
Over the past few decades, coordination polymers/metal organic frameworks （CPs/MOFs） have drawn a great deal of attention for diverse applications due to their advantages of intrinsically ttLnable chemical structure...Over the past few decades, coordination polymers/metal organic frameworks （CPs/MOFs） have drawn a great deal of attention for diverse applications due to their advantages of intrinsically ttLnable chemical structure, flexible architecture, high pore volume, high surface area, multifunctional properties, etc. To date, numerous CPs/MOFs have been developed and employed for the treatment and control of gaseous pollutants, such as volatile organic compounds （VOCs）, through capture, sorptive removal, and catalytic degradation. Nevertheless, there are also some key drawbacks and challenges for the practical application of these systems （e.g., poor selectivity, high energy （and fiscal） cost, high synthesis cost, low capacity, and difficulties in regeneration and recycling）. In this review, recent developments in CPs/MOFs research are described with their associated mechanisms for capture, sorptive removal, and catalytic degradation of VOCs. To this end, we discuss the key variables and challenges for afforded abatement of VOCs through CPs/MOFs technologies. Hopefully, this review will help the scientific community set future directions for the advancement of CPs/MOFs techniques for the effective management of diverse environmental issues.展开更多
Metallic organic compounds of iron, stannum and manganese were introduced into lowdensity polyethylene as catalysts of degradation at low temperatures. The mechanical properties, viscosity\|average molecular weight of...Metallic organic compounds of iron, stannum and manganese were introduced into lowdensity polyethylene as catalysts of degradation at low temperatures. The mechanical properties, viscosity\|average molecular weight of polyethylene and the hydroperoxide concentration in the matrix were measured. It was shown that at 70℃ the adopted additives can catalyze the degradation of polyethylene efficiently. After 60 day’s aging, most of the samples became very fragile, and their molecular weight decreased in large scales. The relationship between molecular weght and hydroperoxide concentration, as well as the mode of the degrading behavior of the prepared matrixes, was also discussed.展开更多
文摘The catalytic effects of the organic compounds of iron,tin and manganese on the degradation of low density polyethylene (LDPE) at compost temperature are discussed.A series of samples were aged in a simulating compost environment.The mechanical properties,viscosity average molecular weight (M η) of PE and hydroperoxide (POOH) concentration in the samples were measured.FT IR and DSC were also applied to characterize some samples.It was shown that the above mentioned metallic organic compounds can catalyze the degradation of LDPE efficiently.After 2 months aging,all samples with catalysts became fragile and the M η of the material decreased dramatically.Furthermore,the concentration of carbonyl and the degree of crystallinity of the material increased with the aging time.
文摘Over the past few decades, coordination polymers/metal organic frameworks （CPs/MOFs） have drawn a great deal of attention for diverse applications due to their advantages of intrinsically ttLnable chemical structure, flexible architecture, high pore volume, high surface area, multifunctional properties, etc. To date, numerous CPs/MOFs have been developed and employed for the treatment and control of gaseous pollutants, such as volatile organic compounds （VOCs）, through capture, sorptive removal, and catalytic degradation. Nevertheless, there are also some key drawbacks and challenges for the practical application of these systems （e.g., poor selectivity, high energy （and fiscal） cost, high synthesis cost, low capacity, and difficulties in regeneration and recycling）. In this review, recent developments in CPs/MOFs research are described with their associated mechanisms for capture, sorptive removal, and catalytic degradation of VOCs. To this end, we discuss the key variables and challenges for afforded abatement of VOCs through CPs/MOFs technologies. Hopefully, this review will help the scientific community set future directions for the advancement of CPs/MOFs techniques for the effective management of diverse environmental issues.
文摘Metallic organic compounds of iron, stannum and manganese were introduced into lowdensity polyethylene as catalysts of degradation at low temperatures. The mechanical properties, viscosity\|average molecular weight of polyethylene and the hydroperoxide concentration in the matrix were measured. It was shown that at 70℃ the adopted additives can catalyze the degradation of polyethylene efficiently. After 60 day’s aging, most of the samples became very fragile, and their molecular weight decreased in large scales. The relationship between molecular weght and hydroperoxide concentration, as well as the mode of the degrading behavior of the prepared matrixes, was also discussed.
