In-situ reactive compatibilization of high-density polyethylene (HDPE)/ground tire rubber (GTR) blends by dicumyl peroxide (DCP) and HY-2045 - a kind of thermoplastic phenolic resin without catalyst was inves...In-situ reactive compatibilization of high-density polyethylene (HDPE)/ground tire rubber (GTR) blends by dicumyl peroxide (DCP) and HY-2045 - a kind of thermoplastic phenolic resin without catalyst was investigated by studying the mor-phology, stress and strain behavior, dynamic mechanical properties and crystallization performance of the blends. Scanning e-lectron microscopy (SEM) results show that there are a lot of fibrous materials distributing in the interface, which connects the dispersed phase with the matrix and obtains better interfacial strength for prominent mechanical properties. The addition of compatibilizers results in the decrease of crystallinity of the blends and the disappearance of an obvious yield phenomenon, which was proved by the differential scanning calorimeter (DSC) test and X-ray diffraction (XRD) characterization Although the crystallinity of the blends decreases,the tensile strength and tensile strain of the blends significantly increases, especially for the HDPE/GTR/DCP/HY-2045 blends, which is possibly attributed to the good compatibility of the blends owing to the in-situ interface crosslinking. In addition, it is found that the compatibilizing HDPE/GTR blends shows a higher tan^ peak temperature and a broaden transition peak for GTR phase.展开更多
Fully biodegradable blends with low shape memory recovery temperature were obtained based on poly(lactic acid)(PLA) and poly(propylene carbonate)(PPC). By virtue of their similar chemical structures, in situ c...Fully biodegradable blends with low shape memory recovery temperature were obtained based on poly(lactic acid)(PLA) and poly(propylene carbonate)(PPC). By virtue of their similar chemical structures, in situ cross-linking reaction initiated by dicumyl peroxide(DCP) between PLA and PPC chains was realized in PLA/PPC blends. Therefore, the compatibility between PLA and PPC was increased, which obviously changed the phase structures and increased the elongation at break of the blends. The compatibilized blends had a recovery performance at 45 °C. Combining the changes of phase structures, the mechanism of the shape memory was discussed. It was demonstrated that in situ compatibilization by dicumyl peroxide was effective to obtain eco-friendly PLA/PPC blends with good mechanical and shape memory properties.展开更多
The thermal decomposition of dicumyl peroxide under the flow nitrogen atmosphere was studied by DSC-TG technique.The non-isothermal kinetics parameters were analyzed by means of the Kissinger and Flynn-Wall-Ozawa meth...The thermal decomposition of dicumyl peroxide under the flow nitrogen atmosphere was studied by DSC-TG technique.The non-isothermal kinetics parameters were analyzed by means of the Kissinger and Flynn-Wall-Ozawa methods,and the thermal decomposition mechanism of dicumyl peroxide was also studied with the Satava-Sestak method.The results showed that there was little difference between kinetic parameters calculated by DSC plot and DTG plot,the apparent activation energy and pre-exponential factor were 120.83 kJ·mol-1 and 9.12×1011s-1,respectively.The thermal decomposition mechanism of dicumyl peroxide in nitrogen was controlled by interface reaction R3.展开更多
文摘In-situ reactive compatibilization of high-density polyethylene (HDPE)/ground tire rubber (GTR) blends by dicumyl peroxide (DCP) and HY-2045 - a kind of thermoplastic phenolic resin without catalyst was investigated by studying the mor-phology, stress and strain behavior, dynamic mechanical properties and crystallization performance of the blends. Scanning e-lectron microscopy (SEM) results show that there are a lot of fibrous materials distributing in the interface, which connects the dispersed phase with the matrix and obtains better interfacial strength for prominent mechanical properties. The addition of compatibilizers results in the decrease of crystallinity of the blends and the disappearance of an obvious yield phenomenon, which was proved by the differential scanning calorimeter (DSC) test and X-ray diffraction (XRD) characterization Although the crystallinity of the blends decreases,the tensile strength and tensile strain of the blends significantly increases, especially for the HDPE/GTR/DCP/HY-2045 blends, which is possibly attributed to the good compatibility of the blends owing to the in-situ interface crosslinking. In addition, it is found that the compatibilizing HDPE/GTR blends shows a higher tan^ peak temperature and a broaden transition peak for GTR phase.
基金financially supported by the National Natural Science Foundation of China(No.51503117)the Innovation Foundation for Graduate Students of Shandong University of Science and Technology,China(No.SDKDYC170334)
文摘Fully biodegradable blends with low shape memory recovery temperature were obtained based on poly(lactic acid)(PLA) and poly(propylene carbonate)(PPC). By virtue of their similar chemical structures, in situ cross-linking reaction initiated by dicumyl peroxide(DCP) between PLA and PPC chains was realized in PLA/PPC blends. Therefore, the compatibility between PLA and PPC was increased, which obviously changed the phase structures and increased the elongation at break of the blends. The compatibilized blends had a recovery performance at 45 °C. Combining the changes of phase structures, the mechanism of the shape memory was discussed. It was demonstrated that in situ compatibilization by dicumyl peroxide was effective to obtain eco-friendly PLA/PPC blends with good mechanical and shape memory properties.
文摘The thermal decomposition of dicumyl peroxide under the flow nitrogen atmosphere was studied by DSC-TG technique.The non-isothermal kinetics parameters were analyzed by means of the Kissinger and Flynn-Wall-Ozawa methods,and the thermal decomposition mechanism of dicumyl peroxide was also studied with the Satava-Sestak method.The results showed that there was little difference between kinetic parameters calculated by DSC plot and DTG plot,the apparent activation energy and pre-exponential factor were 120.83 kJ·mol-1 and 9.12×1011s-1,respectively.The thermal decomposition mechanism of dicumyl peroxide in nitrogen was controlled by interface reaction R3.