The effect of substrate on the phase morphologies of PMMA/PS blend films was investigated by means of phase contrast microscope. PMMA/PS blend films were cast onto various substrates(such as glass substrate and PP sub...The effect of substrate on the phase morphologies of PMMA/PS blend films was investigated by means of phase contrast microscope. PMMA/PS blend films were cast onto various substrates(such as glass substrate and PP substrate) by spin-coating with thickness of about 10 μm. It was observed that there was a large difference of the phase inversion region between the blend films cast on glass and on PP substrates. On glass substrate, the phase inversion occurred at about \%Φ\%_m=0 4(PS mass fraction) while at \%Φ\%_m=0 5 on PP substrate. This implies that there is a shift of the phase inversion region with the change of substrate in cast polymer blend films. In other words, phase inversion region depends on the substrate. ATR-FTIR analysis was used to detect the composition of the surface and the bottom of the films(about 100 μm thick) obtained by evaporating solvent from the polymer blend solution. The ATR-FTIR spectra of the surface and the bottom of the PMMA/PS blend thin films cast on glass substrate and PP substrate showed that PMMA component preferentially segregated to glass substrate and PS component was enriched on the PP substrate. This selective segregation was due to the difference of the wetting abilities of PS and PMMA on the two kinds of substrates. The polymer-substrate interfacial tension γ were calculated and the results supported the ATR-FTIR results. It could be inferred that the shift of the phase inversion region with the change of the substrate in PMMA/PS blend film was due to the fact that the composition of the blend in the bulk changed, owing to the selective enrichment of one component of polymer blend to the substrate. In other words, the affinity between polymer and substrate can strongly influence the phase morphologies and the phase inversion region in polymer blend films.展开更多
为提高锂离子电池聚偏氟乙烯(PVDF)基聚合物隔膜对电解液体系的亲和性和导电性,引入聚甲基丙烯酸甲酯(PMMA)与聚偏氟乙烯(PVDF)进行共混,并添加有机增塑剂聚乙二醇PEG-400对PVDF基聚合物隔膜进行改性研究。采用先干法后湿法的相转化方...为提高锂离子电池聚偏氟乙烯(PVDF)基聚合物隔膜对电解液体系的亲和性和导电性,引入聚甲基丙烯酸甲酯(PMMA)与聚偏氟乙烯(PVDF)进行共混,并添加有机增塑剂聚乙二醇PEG-400对PVDF基聚合物隔膜进行改性研究。采用先干法后湿法的相转化方法制备PVDF/PMMA/PEG型聚合物隔膜。通过对制备的聚合物隔膜的孔隙率、吸液率、微观形貌和电化学性能的分析研究,确定制膜的最佳工艺条件为聚合物占溶剂质量百分比为8%,PVDF∶PMMA=7∶3,增塑剂含量为30%,非溶剂含量为3%,反应温度为45℃,在此最佳工艺条件下制备的PVDF/PMMA/PEG隔膜的离子电导率可达2.848 m S/cm,对电解液体系的亲和性和导电性得到显著提高。展开更多
Thin films of poly(methyl methacrylate)/polystyrene (PMMA/PS 80/20 W/W) blend prepared on glass substrate by spin-coating from a cosolvent, chloroform were studied. The formation of regular Voronoi patterns was found ...Thin films of poly(methyl methacrylate)/polystyrene (PMMA/PS 80/20 W/W) blend prepared on glass substrate by spin-coating from a cosolvent, chloroform were studied. The formation of regular Voronoi patterns was found under phase contrast microscopy (PCM). It was observed that there were clear concave boundaries in the PCM images by atomic force microscopy (AFM). Although the sample was annealed at 220℃ more than 7 h, no changes of the Voronoi pattern occurred, implying that the phase separation structure in the Voronoi pattern was almost complete during spin-coating process. It was believed that the formation of this pattern was due to the convection during spin-coating procedure.展开更多
文摘The effect of substrate on the phase morphologies of PMMA/PS blend films was investigated by means of phase contrast microscope. PMMA/PS blend films were cast onto various substrates(such as glass substrate and PP substrate) by spin-coating with thickness of about 10 μm. It was observed that there was a large difference of the phase inversion region between the blend films cast on glass and on PP substrates. On glass substrate, the phase inversion occurred at about \%Φ\%_m=0 4(PS mass fraction) while at \%Φ\%_m=0 5 on PP substrate. This implies that there is a shift of the phase inversion region with the change of substrate in cast polymer blend films. In other words, phase inversion region depends on the substrate. ATR-FTIR analysis was used to detect the composition of the surface and the bottom of the films(about 100 μm thick) obtained by evaporating solvent from the polymer blend solution. The ATR-FTIR spectra of the surface and the bottom of the PMMA/PS blend thin films cast on glass substrate and PP substrate showed that PMMA component preferentially segregated to glass substrate and PS component was enriched on the PP substrate. This selective segregation was due to the difference of the wetting abilities of PS and PMMA on the two kinds of substrates. The polymer-substrate interfacial tension γ were calculated and the results supported the ATR-FTIR results. It could be inferred that the shift of the phase inversion region with the change of the substrate in PMMA/PS blend film was due to the fact that the composition of the blend in the bulk changed, owing to the selective enrichment of one component of polymer blend to the substrate. In other words, the affinity between polymer and substrate can strongly influence the phase morphologies and the phase inversion region in polymer blend films.
文摘为提高锂离子电池聚偏氟乙烯(PVDF)基聚合物隔膜对电解液体系的亲和性和导电性,引入聚甲基丙烯酸甲酯(PMMA)与聚偏氟乙烯(PVDF)进行共混,并添加有机增塑剂聚乙二醇PEG-400对PVDF基聚合物隔膜进行改性研究。采用先干法后湿法的相转化方法制备PVDF/PMMA/PEG型聚合物隔膜。通过对制备的聚合物隔膜的孔隙率、吸液率、微观形貌和电化学性能的分析研究,确定制膜的最佳工艺条件为聚合物占溶剂质量百分比为8%,PVDF∶PMMA=7∶3,增塑剂含量为30%,非溶剂含量为3%,反应温度为45℃,在此最佳工艺条件下制备的PVDF/PMMA/PEG隔膜的离子电导率可达2.848 m S/cm,对电解液体系的亲和性和导电性得到显著提高。
文摘Thin films of poly(methyl methacrylate)/polystyrene (PMMA/PS 80/20 W/W) blend prepared on glass substrate by spin-coating from a cosolvent, chloroform were studied. The formation of regular Voronoi patterns was found under phase contrast microscopy (PCM). It was observed that there were clear concave boundaries in the PCM images by atomic force microscopy (AFM). Although the sample was annealed at 220℃ more than 7 h, no changes of the Voronoi pattern occurred, implying that the phase separation structure in the Voronoi pattern was almost complete during spin-coating process. It was believed that the formation of this pattern was due to the convection during spin-coating procedure.
文摘采用机械共混法制备了Si O2改性的CPVC/PVDF/PMMA复合材料,考察了Si O2用量、PVB、PVC、丁腈粉、DBP对材料成膜性能、吸墨性能、柔软性和韧性的影响.结果表明:1当Si O2的质量浓度为4.5%时,CPVC的成膜性和吸墨性能最佳;2当DBP、丁腈粉的质量分数分别为3.0%和3.4%时,膜的柔韧性最佳;3最佳的制备工艺是将PMMA、CPVC、PVDF和丁腈粉溶于DMAC和DBP的混合溶液中,再恒温4 h.
