A novel zinc-rich pigment based on P(St-BA-MAA-SPAA) nano-latex was obtained, which is suitable for the use in hot alkali liquid medium. The nano-latex was synthesized by active emulsifier latex polymerization method ...A novel zinc-rich pigment based on P(St-BA-MAA-SPAA) nano-latex was obtained, which is suitable for the use in hot alkali liquid medium. The nano-latex was synthesized by active emulsifier latex polymerization method with monomers of styrene (St), butylacrylate (BA), methylacrylic acid(MAA) in the presence of active emulsifier 3-sulfopropylacrylate(SPAA). The synthesis condition and properties of the latex were investigated. And the anti-corrosive property of the resultant zinc-rich coating was studied. The results show that the nano-latex is self-stabilized and has a narrow particle diameter distribution, the average diameter of the latex particles is 71 nm. Zinc powders can be evenly dispersed in the nano-latex, which indicates that the P(St-BA-MAA-SPAA) nano latex can be used as the binder of zinc-rich coating. The resultant zinc-rich coating is able to resist the invasion of hot alkali solution(the temperature is 95 ℃ and the pH value is 14) for 480 h and the exposure time in salt spray is 1 200 h. Moreover, the coating shows good thermal conductivity and static electricity properties, its thermal conductivity and electric resistivity are 21-37 W/(m·K) and 6.7×105-3.5×106 Ω·cm, respectively.展开更多
Filming process of polystyrene nano-latex (NPS) particles was studied by a combination of various methods. For a constant annealing time of 1 h, the AFM images showed that the deformation and sintering temperatures fo...Filming process of polystyrene nano-latex (NPS) particles was studied by a combination of various methods. For a constant annealing time of 1 h, the AFM images showed that the deformation and sintering temperatures for NFS particles were ca. 90 ℃ and 100 ℃ respectively. In spin-lattice relaxation measurements of solid state NMR, it is found that TIL, T1S and /1L/I0 increased significantly after annealing at 90℃ and above. DSC results showed that there was an exothermic peak near Tg after annealing for 1 h at the selected temperatures below 95℃; otherwise, the exothermic peak disappeared after annealing at 100℃ or above. The apparent density of NPS increased suddenly in the temperature range. The results implied that the macromolecules in NPS particles are in a confined state with higher confor-mational energy and less cohensional interactions which are the drive force for the sintering at a lower temperature compared with the multichain PS particles and the bulk polymer.展开更多
The influence factors on NR latex medical product modified with nano-CaCO3 were studied.The result showed that the good properties of NR latex medical products were obtained in the conditions that the content of surfa...The influence factors on NR latex medical product modified with nano-CaCO3 were studied.The result showed that the good properties of NR latex medical products were obtained in the conditions that the content of surface conditioning agent,nano-CaCO3 powder were 2.5% and 3%,respectively.Meanwhile,the stirring times,which were needed for the modifying of nano-CaCO3 surface,were 20 minutes.展开更多
文摘A novel zinc-rich pigment based on P(St-BA-MAA-SPAA) nano-latex was obtained, which is suitable for the use in hot alkali liquid medium. The nano-latex was synthesized by active emulsifier latex polymerization method with monomers of styrene (St), butylacrylate (BA), methylacrylic acid(MAA) in the presence of active emulsifier 3-sulfopropylacrylate(SPAA). The synthesis condition and properties of the latex were investigated. And the anti-corrosive property of the resultant zinc-rich coating was studied. The results show that the nano-latex is self-stabilized and has a narrow particle diameter distribution, the average diameter of the latex particles is 71 nm. Zinc powders can be evenly dispersed in the nano-latex, which indicates that the P(St-BA-MAA-SPAA) nano latex can be used as the binder of zinc-rich coating. The resultant zinc-rich coating is able to resist the invasion of hot alkali solution(the temperature is 95 ℃ and the pH value is 14) for 480 h and the exposure time in salt spray is 1 200 h. Moreover, the coating shows good thermal conductivity and static electricity properties, its thermal conductivity and electric resistivity are 21-37 W/(m·K) and 6.7×105-3.5×106 Ω·cm, respectively.
基金This work was supported by the National Key Project for Fundamental Research the State Science and Technology Commission of China (Grant No. 95-11) and the National Natural Science Foundation of China (Grant Nos. 20004011 and 20023003).
文摘Filming process of polystyrene nano-latex (NPS) particles was studied by a combination of various methods. For a constant annealing time of 1 h, the AFM images showed that the deformation and sintering temperatures for NFS particles were ca. 90 ℃ and 100 ℃ respectively. In spin-lattice relaxation measurements of solid state NMR, it is found that TIL, T1S and /1L/I0 increased significantly after annealing at 90℃ and above. DSC results showed that there was an exothermic peak near Tg after annealing for 1 h at the selected temperatures below 95℃; otherwise, the exothermic peak disappeared after annealing at 100℃ or above. The apparent density of NPS increased suddenly in the temperature range. The results implied that the macromolecules in NPS particles are in a confined state with higher confor-mational energy and less cohensional interactions which are the drive force for the sintering at a lower temperature compared with the multichain PS particles and the bulk polymer.
文摘The influence factors on NR latex medical product modified with nano-CaCO3 were studied.The result showed that the good properties of NR latex medical products were obtained in the conditions that the content of surface conditioning agent,nano-CaCO3 powder were 2.5% and 3%,respectively.Meanwhile,the stirring times,which were needed for the modifying of nano-CaCO3 surface,were 20 minutes.
