A novel polypropylene random(PPR)composite materials with optimized properties was developed by addingβ-nucleating compound agents(rare earth complex WBG-2 and aryl amide derivative TMB-5)and ternary compound modifie...A novel polypropylene random(PPR)composite materials with optimized properties was developed by addingβ-nucleating compound agents(rare earth complex WBG-2 and aryl amide derivative TMB-5)and ternary compound modifier(TPE/WBG-2/CaCO_(3)).The effects of differentβ-nucleating agents and ternary compound modifier on the mechanical properties and crystallization behavior of PPR were analyzed.The results show that,compared with pure PPR materials,both WBG-2 and TMB-5 could significantly improve the impact strength of PPR.The crystallization temperature of PPR increased with the addition ofβ-nucleating agent.The modified PPR prepared with ternary compound modifier showed the most excellent comprehensive properties.展开更多
Long chain branched polypropylene random copolymers(LCB-PPRs) were prepared via reactive extrusion with the addition of dicumyl peroxide(DCP) and various amounts of 1,6-hexanediol diacrylate(HDDA) into PPR. Fourier tr...Long chain branched polypropylene random copolymers(LCB-PPRs) were prepared via reactive extrusion with the addition of dicumyl peroxide(DCP) and various amounts of 1,6-hexanediol diacrylate(HDDA) into PPR. Fourier transform infrared spectrometer(FTIR) was applied to confirm the existence of branching and investigate the grafting degree for the modified PPRs. Melt flow index(MFI) and oscillatory shear rheological properties including complex viscosity,storage modulus, loss tangent and the Cole-Cole plots were studied to differentiate the LCB-PPRs from linear PPR.Differential scanning calorimetry(DSC) and polarized light microscopy(PLM) were used to study the melting and crystallization behavior and the spherulite morphology, respectively. Qualitative and quantitative analyses of rheological curves demonstrated the existence of LCB. The effect of the LCB on crystalline morphology, crystallization behavior and molecular mobility, and, thereby, the mechanical properties were studied and analyzed. Due to the entanglements between molecular chains and the nucleating effect of LCB, LCB-PPRs showed higher crystallization temperature and crystallinity,higher crystallization rate, more uniformly dispersed and much smaller crystallite compared with virgin PPR, thus giving rise to significantly improve impact strength. Moreover, the LCB-PPRs exhibited the improved yield strength. The mobility of the molecular chain segments, as demonstrated by dynamic mechanical analysis(DMA), was improved for the modified PPRs, which also contributed to the improvement of their mechanical properties.展开更多
基金Funded by the Natural Science Foundation of Liaoning Province of China(No.20180550432)Natural Science Foundation for Young Doctoral Research(No.2020-BS-158)Basic Scientific Research Project of Colleges and Universities of Liaoning Provincial Department of Education(No.LJKQZ2021060)。
文摘A novel polypropylene random(PPR)composite materials with optimized properties was developed by addingβ-nucleating compound agents(rare earth complex WBG-2 and aryl amide derivative TMB-5)and ternary compound modifier(TPE/WBG-2/CaCO_(3)).The effects of differentβ-nucleating agents and ternary compound modifier on the mechanical properties and crystallization behavior of PPR were analyzed.The results show that,compared with pure PPR materials,both WBG-2 and TMB-5 could significantly improve the impact strength of PPR.The crystallization temperature of PPR increased with the addition ofβ-nucleating agent.The modified PPR prepared with ternary compound modifier showed the most excellent comprehensive properties.
基金financially supported by the Foundation for Development of Science and Technology of Fuzhou University(No.2011-XY-1)
文摘Long chain branched polypropylene random copolymers(LCB-PPRs) were prepared via reactive extrusion with the addition of dicumyl peroxide(DCP) and various amounts of 1,6-hexanediol diacrylate(HDDA) into PPR. Fourier transform infrared spectrometer(FTIR) was applied to confirm the existence of branching and investigate the grafting degree for the modified PPRs. Melt flow index(MFI) and oscillatory shear rheological properties including complex viscosity,storage modulus, loss tangent and the Cole-Cole plots were studied to differentiate the LCB-PPRs from linear PPR.Differential scanning calorimetry(DSC) and polarized light microscopy(PLM) were used to study the melting and crystallization behavior and the spherulite morphology, respectively. Qualitative and quantitative analyses of rheological curves demonstrated the existence of LCB. The effect of the LCB on crystalline morphology, crystallization behavior and molecular mobility, and, thereby, the mechanical properties were studied and analyzed. Due to the entanglements between molecular chains and the nucleating effect of LCB, LCB-PPRs showed higher crystallization temperature and crystallinity,higher crystallization rate, more uniformly dispersed and much smaller crystallite compared with virgin PPR, thus giving rise to significantly improve impact strength. Moreover, the LCB-PPRs exhibited the improved yield strength. The mobility of the molecular chain segments, as demonstrated by dynamic mechanical analysis(DMA), was improved for the modified PPRs, which also contributed to the improvement of their mechanical properties.
