共查询到19条相似文献,搜索用时 93 毫秒
1.
凝固浴条件对PU/PVDF共混膜结构与性能的影响 总被引:1,自引:0,他引:1
用浸没沉淀相转化法,制得聚氨酯(PU)/聚偏氟乙烯(PVDF)共混膜,研究了凝固浴条件对共混膜形貌及性能的影响.结果表明,凝固浴为5%N,N-二甲基乙酰胺(DMAc)水溶液,膜中呈现海绵状孔结构;随凝固浴中乙醇或甘油含量的增多,孔结构向海绵状转变;乙醇或甘油的添加,使PVDF结晶在共混膜下表面与PU一起以界面孔的形式存... 相似文献
2.
3.
4.
制备了PVDF(聚偏氟乙烯)/PVC(聚氯乙烯)/PMMA(聚甲基丙烯酸甲酯)三元共混中空纤维膜,讨论了影响膜性能的主要因素.正交实验结果表明:在PVDF/PVC/PMMA体系中,聚合物总浓度是影响膜的水通量的主要因素;PVDF浓度对膜强度影响最大;PMMA对膜的亲水性有较大的贡献.得到优化的制膜条件为:铸膜液中PVDF:PVC:PMMA=7:1.2:1.8(质量比),聚合物溶质的总质量分数为17%;添加剂吐温-80的质量分数为6%. 相似文献
5.
PVDF疏水中空纤维膜的膜蒸馏含盐废水处理性能研究 总被引:5,自引:0,他引:5
利用新型高通量聚偏氟乙烯(PVDF)中空纤维疏水膜,对石化企业废水经反渗透(RO)处理的浓排水进行减压膜蒸馏(VMD)处理实验.研究了RO浓排水流速、温度和冷侧真空度对VMD过程中PVDF膜性能的影响,考察了PVDF膜在VMD法RO浓水浓缩过程中的性能变化.结果表明,原液流速对膜性能无明显影响;原液温度或冷侧真空度提高都会使膜的产水通量明显上升,而产水电导保持稳定.在冷侧真空度为-0.095MPa、原液温度70℃、流速0.66m/s的条件下,经15.2h实验,将RO浓排水浓缩20倍,膜的产水通量从25.8L/(m2*h)降低至11.8L/(m2*h),产水电导低于4霺/cm,脱盐率高于99.99%,产水CODCr值约30mg/L.经过5次浓缩实验后,PVDF膜的通量和产水电导均保持稳定. 相似文献
6.
7.
通过马来酸酐和苯乙烯合成了苯乙烯/马来酸交替共聚物(SMA),并按不同质量比与聚偏氟乙烯(PVDF)共混,通过溶液相转化成膜法制备了PVDF/SMA共混膜。采用红外光谱、扫描电镜、膜通量测试等对不同铸膜液所形成膜的结构和性能进行了研究。结果表明,随着铸膜液中交替共聚物含量增大,所成膜及膜表面交替共聚物含量增大,膜孔尺寸增大,膜孔隙率升高,纯水通量增大,蛋白质截流能力下降,膜表面亲水性和耐蛋白污染能力增强。 相似文献
8.
探讨了聚偏氟乙烯(PVDF)/聚甲基丙烯酸甲酯(PMMA)共混挤出流延膜的结构和性能.研究结果表明:PMMA的加入能够大大改善其微观结构,不但使结晶度降低,而且红外分析(IR)和广角x射线衍射(WXRD)证实,其中部分α晶型能明显地转变成β晶型;TGA研究表明,共混体系的稳定性比纯粹的PMMA稳定性提高,但PVDF的热稳定性只有很少降低;流变性能研究显示,PMMA含量在很宽的范围内体系扭矩变化不大,为选择加工条件提供了依据;力学性能测试显示出共混膜具有很好的力学性能.PVDF/PMMA共混挤出膜被证明是一种很有前途的薄膜材料. 相似文献
9.
用L-S相转换法制备了聚偏氟乙烯中空纤维不对称滤膜,铸膜液由聚合物,溶剂和添加剂组成。用电子显微镜考察了聚合物浓度,添加剂用量及种类对膜形态结构的影响。 相似文献
10.
PVDF疏水中空纤维膜与组件对真空膜蒸馏性能的影响 总被引:4,自引:0,他引:4
利用高孔隙率的聚偏氟乙烯(PVDF)中空纤维疏水膜进行真空膜蒸馏(VMD)脱盐实验.在真空度0.095MPa,盐水温度60℃,流速1.5kg/min的条件下,着重研究了中空纤维膜内径、壁厚,组件长度、装填纤维数目等结构参数对VMD性能的影响.结果表明:组件长度或装填纤维数目增加,组件产水通量明显降低而总产水通量明显提高;中空纤维膜内径对VMD产水通量影响较小,而膜壁厚增加使通量明显降低;用内径1.0mm壁厚0.1mm的膜制成的长度21cm装填纤维50根的膜组件,产水通量达到21.8kg/(m2·h).VMD过程产水的电导率保持在4μS/cm以内,脱盐率达99.99%,受膜、组件结构及操作条件影响很小. 相似文献
11.
12.
13.
《Materials Science & Technology》2013,29(3):661-665
Melt spinning and stretching process was used to prepare polyurethane/poly(vinylidene difluoride) (PU/PVDF) blend hollow fibre membrane in this study. Rheological properties of melts of PU, PVDF and their blends were studied by observing their melting viscosity changing with shear rate and temperature. Morphologies of PU/PVDF blend hollow fibre membranes with different mass ratios were also observed by SEM and results showed that PU/PVDF mass ratio of 3:1 was relatively better condition for membrane preparation. The forming mechanism of the interfacial microvoids in PU/PVDF blends was also investigated and PU/PVDF blend hollow fibre membrane with water flux of ~2174 L m?2 h?1 was finally obtained under the pressure of 0·1 MPa. 相似文献
14.
15.
16.
Jing SUN Lu YAO Qiao-Ling ZHAO Jin HUANG Rui SONG Zhi MA Ling-Hao HE Wei HUANG Yong-Mei HAO 《材料科学前沿(英文版)》2011,5(4):388
The crystallization modification of poly(vinylidene fluoride) (PVDF) was investigated for the blend films of PVDF and poly(methyl methacrylate) (PMMA). The mass crystallinity (χ c) and further, the β-phase content (F (β)) of PVDF, were studied for the as-prepared blend films with different mass ratios. In addition, the variations of χ c and F (β) were systematically probed once the PMMA component was removed from the related blend systems. DSC, FTIR and XRD measurements all indicated that 1) χ c, F (β) and even the content of α-phase (F (α)) decreased with the addition of PMMA; 2) with the extraction of PMMA, both χ c and F (β) increased while F (α) decreased. It is worth noting that the increase of χ c and F (β) depended on the relative amount of extracted PMMA (E PMMA), i.e., the more PMMA was removed, the more χ c and F (β) increased. These results reveal the hindrance effect from the PMMA constituent to the crystallization of PVDF, and consequently, this restriction would be released when the PMMA was extracted. 相似文献
17.
18.
采用二甲基乙酰胺为溶剂,聚乙烯吡咯烷酮(PVP K90)为致孔性添加荆,研究了PVP的浓度对聚偏氟乙烯/聚醚砜(PVDF/PES)共混膜的收缩率、纯水通量、牛血清蛋白(BSA)截留率和膜结构的影响.在PVP含量为5%时,共混膜的收缩率最低,水通量取得极大值,截留率有一极小值. 相似文献