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1.
在水溶液中以过硫酸铵((NH4)2S2O8)和亚硫酸氢钠(NaHSO3)为引发体系,利用原位聚合法合成了聚丙烯酰胺(PAM)-氢氧化铁(Fe(OH)3)有机-无机杂化型高分子絮凝剂.通过正交实验得到合成杂化絮凝剂的最佳条件为:反应温度40℃,引发剂质量分数0.5%,丙烯酰胺质量分数30%,反应时间7 h.FT-IR、T...  相似文献   

2.
有机-无机杂化高分子絮凝剂PAC-PDMDAAC的合成与表征   总被引:1,自引:0,他引:1  
以过硫酸铵为引发剂,以乙二胺四乙酸四钠(Na4EDTA)为助剂合成了新型有机-无机杂化高分子絮凝剂聚合氯化铝-聚二甲基二烯丙基氯化铵(PAC-PDMDAAC).实验考查了DMDAAC单体质量分数、引发剂用量、反应温度以及反应时间对杂化絮凝剂合成的影响.结果表明杂化高分子絮凝剂的最佳合成条件为单体质量分数30%,引发剂质量分数0.7%,反应温度60℃,反应时间5 h.傅里叶红外光谱(FTIR)、热重分析(TGA)以及扫描电镜(SEM)测试结果表明,杂化聚合物PDMDAAC链端有—SO42-离子存在,其与带正电荷的羟基铝粒子以离子键形式键合.扫描电镜结果显示杂化絮凝剂具有更大的比表面积,易于发挥吸附架桥作用.采用Al-Ferron逐时络合比色法研究絮凝剂中Al形态,结果表明杂化絮凝剂中Alc部分,即不与Ferron发生络合反应的高聚物明显增多.由PAC、复配型PAC-PDMDAAC和杂化型PAC-PDMDAAC絮凝剂分别处理腐植酸-高岭土模拟水样和长江水,结果表明杂化型絮凝剂在浊度和UV254的去除率上优于其它二者.  相似文献   

3.
焦磷酸络锰三价离子引发淀粉-丙烯酰胺的接枝共聚合   总被引:2,自引:0,他引:2  
将带有极性基团的乙烯类单体通过化学接枝到淀粉或纤维素之类的天然多糖上,可作为絮凝剂、脱除剂和粘接剂[1~3],近来已发展为高吸水性材料和石油分离剂[4]。用Ce4+引发乙烯类单体接枝到淀粉和纤维素类已有报道[5]。Rayonier用Mn3+的焦磷酸盐络合物引发接枝乙烯类单体至纤维素及其衍生物上[6];Cenita等用Mn3+引发MMA、AN接枝淀粉[7]。本文以焦磷酸络锰离子(Mn3+)作引发剂、丙烯酰胺(AM)为单体、淀粉为接枝基体进行接枝共聚,这一工作目前在国内外尚未见报道。  相似文献   

4.
锰盐引发微晶纤维素—丙烯酰胺接枝共聚所得共聚混和物:纤维素—丙烯酰胺接枝共聚物(GCAM)和丙烯酰胺均聚物(PAM)在实验室条件下处理洗煤皮水,取得了良好的效果。研究了混和物中接枝物、均聚物、水解度、用混和物作非离子絮凝剂、阴离子絮凝剂对处理洗煤废水的影响及絮凝剂与洗煤废水pI值的关系。  相似文献   

5.
采用聚偶氮酯引发剂,合成了聚苯乙烯/聚丙烯酰胺嵌段聚合物(PSt/PAM)。考察了含偶氮基聚苯乙烯预聚物(pre-PSt)在1,4-二氧六环中引发AM的聚合反应行为,讨论了影响第二单体转化率和聚苯乙烯均聚物含量的因素。用元素分析、溶解性、红外光谱、DSC、TG和裂解色谱表征了PSt/PAM嵌段聚合物。  相似文献   

6.
采用聚合和交联的SiO2有机/无机杂化溶胶作为基材, 通过与两性离子单体层之间的过渡层, 在紫外光作用下引发杂化溶胶和两性离子单体溶液中的双键反应, 使生成的杂化层在基材和表面的两性离子聚合物之间形成辅助性黏接作用, 从而在基材表面构筑两性离子水凝胶层. 通过傅里叶红外光谱(FTIR)、 原子力显微镜(AFM)和接触角测试等方法对所制备的两性离子水凝胶层和杂化层的表面进行了表征. 以空白玻璃片为对照样品, 以金黄色葡萄球菌和大肠杆菌为试验菌, 研究了用两性离子凝胶层修饰的玻璃表面的抗细菌黏附性能. 结果表明, 在SiO2杂化过渡层中引入线型-Si-(CH2)2-O-链段可有效提高杂化过渡层对基材的附着力, 并改善其柔韧性. 与对照样品相比, 用两性离子凝胶层修饰的玻璃表面具有优异的抗菌黏附性能.  相似文献   

7.
采用紫外光照射下光敏引发聚合技术,以丙烯酰胺(AM)为单体,以水溶性光敏剂为引发剂,合成了分子量较高的聚丙烯酰胺(PAM)。探讨了光敏引发剂浓度、单体浓度、Na2CO3浓度、pH、络合剂乙二胺四乙酸二钠盐(EDTA)浓度等因素对PAM分子量的影响,通过红外光谱对产物结构进行了表征。结果表明:光敏引发合成的PAM黏均分子量可以达到1.7×107,溶解性能良好,纯度较高。  相似文献   

8.
聚合方法对一种正离子聚丙烯酰胺结构与性能的影响   总被引:2,自引:0,他引:2  
对相同进料比下,以过硫酸胺/亚硫酸氢钠为氧化还原引发剂,分别用溶液法和反相微乳液法合成的丙烯酰胺(AM)与2-甲基丙烯酰氧乙基三甲基氯化胺(MADQUAT)的共聚物P(AM-MADQUAT),根据单体竞聚率计算了两种共聚物的序列分布和组成分布.考察了两种聚合物结构对高岭土絮体尺寸、zeta电位降以及絮体压缩屈服应力的影响,初步建立了不同聚合方法合成的阳离子聚丙烯酰胺结构与絮凝性能之间的相关性.  相似文献   

9.
用可溶性淀粉为原料,通过接枝改性合成了一种淀粉基阳离子絮凝剂(MSF),其最佳制备工艺条件为:淀粉与丙烯酰胺的质量比为1:2,引发剂用量为0.6 g,反应温度为50 ℃,接枝时间为3.5 h;阳离子化条件为:甲醛和二甲胺摩尔比为1.0:1.4,反应时间2.5 h,反应温度50 ℃.产物结构经FTIR证实.用其处理番茄废水后,废水的透光率提高了78.2%、TOC下降了22.5%、COD下降了37.25%,结果表明该产品对高浓度有机废水的絮凝性能优于聚丙烯酰胺高分子絮凝剂(PAM).  相似文献   

10.
以煤油为连续相,水为分散相,Span-80/Tween-80为复配乳化剂,过硫酸铵为引发剂,丙烯酰胺、丙烯酸和氨水为原料,采用反相乳液聚合法合成了丙烯酰胺-丙烯酸铵共聚物絮凝剂.考察了乳化剂种类及用量、引发剂浓度、单体浓度、EDTA用量、聚合温度等对共聚物特性黏数的影响.确定了最佳实验条件,利用FTIR对样品进行了表征.  相似文献   

11.
The pyrolytic highly oriented graphite polymer film (PGS) was first employed to analyze low‐mass analytes in environmental analysis by surface‐assisted laser desorption/ionization mass spectrometry (SALDI‐MS). PGS is a synthetic uniform and highly oriented graphite polymer film with high thermal anisotropic conductivity. We have found that negative ion mode SALDI‐MS using oxidized PGS (PGS‐SALDI‐MS) can be used to detect [M–H]? ions from perfluorooctanoic acid (PFOA) and other perfluoroalkylcarboxylic acids when the PGS surface is modified with the cationic polymer polyethyleneimine (PEI). The signal intensity of PFOA when employing the PEI modification showed a ten‐fold increase over that obtained from desorption/ionization on porous silicon (DIOS). PFOA was quantified using PGS‐SALDI‐MS and the calibration curve showed a wide linear dynamic range of response (20–1000 ppb). The combination of atmospheric pressure ionization and PGS (AP‐PGS‐SALDI) showed greater signal intensity than vacuum PGS‐SALDI for deprotonated PFOA. Several other environmentally important chemicals, including perfluoroalkylsulfonic acid, pentachlorophenol, bisphenol A, 4‐hydroxy‐2‐chlorobiphenyl, and benzo[a]pyrene, were also successfully used to evaluate PGS‐SALDI‐MS. In addition, we found that nonafluoro‐1‐butanesulfonic acid was able to produce protonated peptides in positive ion PGS‐SALDI‐MS, but that perfluoropentanoic acid and trifluoroacetic acid were not. It is suggested that perfluoroalkylsulfonic acids are better protonating agents than perfluoroalkylcarboxylic acids in SALDI‐MS. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

12.
聚合物/层状无机物纳米复合材料因具有常规复合材料所没有的结构、形态及较常规聚合物基复合材料更优异的性能而引起人们的广泛关注.α-磷酸锆(α-ZrP)作为一种合成的结构规整的层状无机物,其离子交换容量(600mmol/100g)是粘土的6倍,并具有长径比可控和粒子尺寸分布较窄等特点,是制备聚合物/层状无机物纳米复合材料的优良基体.以往的研究工作主要集中于金属氧化物/α-ZrP层柱材料和聚电解质膜两类复合材料,有关聚合物/α-ZrP插层复合材料的研究报道较少.聚丙烯酰胺(PAM)是一种具有广泛用途的水溶性高分子,作为聚电解质,  相似文献   

13.
固相酸解法制备古糖酯寡糖及其电喷雾质谱分析   总被引:3,自引:1,他引:2  
以褐藻酸中分离的聚古罗糖醛酸(PG)为原料, 以三氧化硫-吡啶为硫酸酯化试剂, 采用正交实验法确定了制备高硫酸酯基取代古糖酯(PGS)的最佳工艺条件, 并采用2D-NMR分析对其结构进行了确证. 本文建立了一种新的环境友好型固相酸解方法以制备PGS的寡糖(即采用732#阳离子交换树脂这种固态酸对PGS进行降解). 结果表明, 当732#阳离子交换树脂用量为200 mg/mL、PGS的质量分数为2%时, 在100 ℃下降解6 h可得到重均分子质量(Mw)小于3000的PGS寡糖, 经Bio-Gel P6凝胶层析柱分离可以得到13个聚合度单一的寡糖组分F1~F13. 电喷雾质谱(ESI-MS)分析结果表明, F1~F13分别是聚合度为1~13的PGS寡糖.  相似文献   

14.
多磺化侧链型聚芳醚的合成及性能   总被引:1,自引:0,他引:1  
本文通过对聚合物的结构设计,采用亲和取代的途径制备了含有甲氧基侧链的聚芳醚聚合物,然后去醚化得到了侧链含有羟基的聚芳醚材料,最后通过接枝的方法将磺酸基团引入聚合物成功的制备出多磺化侧链型聚芳醚质子交换膜材料。此类材料表现出好的热化学稳定性, 80 oC时的质子传导率可达到0.192 S/cm,超过了Nafion 117 薄膜的传导率.同时此类材料表现出低的尺寸稳定性。因此此类材料很有希望在质子交换膜领域得到应用  相似文献   

15.
The novel copolymers of acrylamide (AM) with complex pseudorotaxane monomer (BAMACB) of butyl ammonium methacrylate (BAMA) and cucurbit[6]uril (CB[6]) were prepared via free‐radical polymerization in aqueous solution. The copolymers containing pseudorotaxane (PAM/BAMACB) were characterized by 1H‐NMR, FTIR, elemental analysis, TGA, and DSC. The glass transition temperature (Tg) of the copolymer PAM/BAMACB are higher than that of the copolymer of acrylamide and butyl ammonium methacrylate (PAM/BAMA) because of the enhanced rigidity and the bulky steric hindrance of BAMACB side chain in PAM/BAMACB. The molecular weights of copolymer PAM/BAMACB were obtained via static light scattering. The hydrodynamic radii of coils or aggregates were investigated by dynamic light scattering. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 5999–6008, 2008  相似文献   

16.
茂钛催化剂的苯乙烯间规聚合   总被引:12,自引:2,他引:10  
比较了几种庞钛化合物/甲基铝氧烷/三甲基铝均相催化剂的苯乙烯间规聚合,认为茂基三正丙氧基钛[CpTi(O-n-Pr)3]是苯乙烯间规聚合的良好催化剂[催化效率:ωps·ωTi-1=4×104g·g-1].探索了催化剂浓度、单体浓度、聚合温度和时间对苯乙烯聚合的影响.聚合反应产物用佛丁酮萃取,沸丁酮不可溶级分大于95%,经13CNMR分析该级分为间规聚苯乙烯.  相似文献   

17.
A novel flocculant of Al(OH)3-polyacrylamide ionic hybrid   总被引:3,自引:0,他引:3  
A novel flocculant based on hybrid Al(OH)(3)-polyacrylamide (HAPAM) has been synthesized using a redox initiation system ((NH(4))(2)S(2)O(8)-NaHSO(3)) at 40 degrees C in aqueous medium. The HAPAM was characterized by viscometry, IR spectroscopy, TEM, conductivity, and TGA. The flocculation behavior for 0.25 wt% kaolin suspension was evaluated by spectrophotometry and phase contrast microscopy. It was found that an ionic bond exists between Al(OH)(3) colloid and polyacrylamide (PAM) chains in the HAPAM and the flocculation efficiency of HAPAM is much better than that of commercial polyacrylamide (PAM) and PAM/AlCl(3) blend.  相似文献   

18.
Novel copolymers based on acrylamide(AM)and complex pseudorotaxane monomer N’-(3-vinylbenzyl)-1,4- diaminobutane dihydrochloride with cucurbit[6]uril(CB[6])(3VBCB)were prepared via free-radical polymerization in aqueous solution,and characterized by 1H-NMR,FT-IR,elemental analysis and static light scattering.The compositions of the copolymers(PAM3VBCB)with pseudorotaxane units were determined by 1H-NMR and elemental analysis.Thermal properties of the copolymers were studied by TGA,and the effects of the copolymer concentration and pH on the average hydrodynamic radius(Rh)of the copolymer molecules were studied by dynamic light scattering(DLS).The experiment data show that CB[6]beads are localized on 1,4-diaminobutane units in side chains of the copolymers.TGA results show that thermal stability of the copolymer increases with increasing the content of pseudorotaxane unit because of the enhanced rigidity and the bulky steric hindrance of 3VBCB in side chains of PAM3VBCB.DLS data show that the average hydrodynamic radius of copolymer molecules increases with the increase in the copolymer concentration,and both the pH and electrical conductivity of PAM3VBCB solutions demonstrate an acute change with addition of NaOH because of CB[6] dethreading from the side chains of PAM3VBCB.CB[6]threading and dethreading of PAM3VBCB could be controlled by addition of BaCl2 and Na2SO4  相似文献   

19.
张庆轩  李玉伟  王晶  杨国华  王宗贤 《应用化学》2011,28(10):1122-1129
以聚乙烯吡咯烷酮(PVP)为稳定剂,亚硫酸氢钠和过硫酸铵为引发剂(I),丙烯酰胺(AM)为单体,在体积分数为90%的乙醇水溶液中,采用分散聚合方法合成了聚丙烯酰胺(PAM)双水相乳液。 考察了聚合反应温度、引发剂质量分数、单体质量分数、PVP质量分数对分散聚合转化率、聚合速率、聚合物分子量和乳液稳定性等性质的影响。 结果表明,AM质量分数从10%提高至25%时,初始聚合速率、最终转化率及聚合物相对分子质量增大,其中初始聚合速率增大约20倍。 但单体质量分数不可过高,否则会因体系粘度过大而形成凝胶。 PVP质量分数增大,初始聚合速率及最终转化率变小,但PVP质量分数过大和过小均不利于双水相乳液的稳定。 随着温度的升高,聚合速率显著增加,而聚合物相对分子质量从20 ℃时的5.08×105降至70 ℃时的0.39×105。 引发剂的质量分数从0.05%增加至0.15%时,单体AM转化率增大,而聚合物PAM的相对分子质量则从4.31×105降至3.73×105。 当引发剂质量分数为0.05%时,反应存在20~25 min的诱导期,导致最大聚合速率推后60 min左右出现。 AM、引发剂和稳定剂的质量分数分别为15%、0.05%和6%时,在30 ℃下反应6 h所得乳液的粒径范围为10~75 μm,平均粒径为21.94 μm。 粒径较大且分布较宽,乳液稳定性较差。 转化率50%时分散聚合速率与各组分质量浓度的关系为:rp=kρ0.33Iρ0.84AMρ-2.56PVP,聚合反应表观活化能为40.95 kJ/mol。  相似文献   

20.
Crosslinked macroporous polyacrylamide (PAM) was prepared with inverse phase suspension polymerization technique.After treatment with hydrazine,the polymer was functionalized with chloroacetic acid,trifluoroacetic acid diethylenetriaminepentaacetic acid (DEPAA),and maleic acid,respectively,and PAM based adsorbents beating carboxyl functional groups for low density lipoprotein (LDL) apheresis use were obtained.The blood compatibility and the adsorption properties for plasma lipoproteins of PAM based adsorbents were investigated.  相似文献   

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