反相悬浮聚合法合成高吸水性树脂的研究

以环己烷为分散介质,聚乙烯醇为主分散剂,十二烷基磺酸钠为助分解剂,Ｎ,Ｎ－亚甲基双丙烯酰胺为交联剂,过硫酸钾为引发剂,采用反相悬浮聚合法合成了丙烯酸－丙烯酸－丙烯酰胺三元共聚交联型高吸水性树脂,产物呈软珠粒状。吸自来水达６５０倍,０．９％的生理盐水达７５倍。     

三元共聚反相悬浮聚合法合成高吸水性树脂的研究

以丙烯酸、丙烯酰胺、2－丙烯酰胺－2－甲基丙磺酸为原料，过硫酸钾为引发剂，N，N－亚甲基双丙烯酰胺为交联剂，环已烷为连续相，水为分散相，以Span-60为悬浮分散剂，用反相悬浮聚合法合成了一系列高吸水性树脂，考察了合成条件对树脂吸水率的影响。     

反相悬浮聚合法制备XG-g-PAA高吸水性树脂

采用黄原胶(XG)为基体,丙烯酸(AA)为接枝聚合单体,环己烷为连续相,过硫酸钾为引发剂,利用反相悬浮聚合法合成了XG-g-PAA高吸水性树脂。研究了丙烯酸与黄原胶质量比、引发剂(KPS)用量、交联剂(NMBA)用量、丙烯酸中和度和聚合反应温度等因素对树脂吸水率的影响。利用傅立叶变换红外光谱仪(FTIR)、扫描电镜(SEM)和热重分析仪(TGA)对产物进行了表征。结果表明,丙烯酸与黄原胶发生接枝共聚,在最佳工艺条件下制备的XG-g-PAA高吸水性树脂具有良好的吸水和抗盐性能,高温保水性能提高,对蒸馏水的吸水率为845 g.g-1,对质量分数0.9%的NaCl水溶液的吸水率为96.3 g.g-1,接枝率达126.5%,接枝效率达82.6%。     

反相悬浮聚合法制备XG-g-PAA高吸水性树脂的研究

采用黄原胶为基体, 丙烯酸(AA)为接枝聚合单体,环己烷为连续相,过硫酸钾为引发剂,利用反相悬浮聚合法合成了XG-g-PAA高吸水性树脂。研究了丙烯酸与黄原胶质量比、引发剂(KPS)、交联剂(NMBA)用量、丙烯酸中和度和聚合反应温度等因素对树脂吸水率的影响。利用傅立叶红外光谱(FT-IR)、扫描电镜(SEM)和热重分析仪（TGA）进行了表征。结果表明：丙烯酸分子与黄原胶发生接枝共聚,在最佳工艺条件下制备的XG-g-PAA高吸水性树脂具有良好的吸水和抗盐性能,高温保水性能提高,对蒸馏水的吸收率为845 g.g-1, 0.9%的NaCl溶液的吸水率为96 g.g-1,接枝率达126.5%,接枝效率达82.6%。     

反相悬浮法制备高吸水性水凝胶的系统研究

高吸水性水凝胶因其具有高吸水/保水性、很好的生物相容性和生物可降解性,在林业、卫生、生物医疗、环境工程、电化学等领域有着广泛应用。系统地研究了影响反相悬浮法制备高吸水性水凝胶性能的各种因素,最终确定最佳制备工艺条件,同时对制备的高吸水性水凝胶进行了结构表征。     

反相悬浮法合成PNaAA高吸水性树脂的聚合工艺

采用反相悬浮法合成PNaAA高吸水性树脂。研究了聚合初始温度、搅拌转速、分散剂的种类及用量等对聚合稳定性、树脂粒径和吸水性能的影响。结果表明:在聚合初始温度为50℃、以Span-60为分散剂、分散剂用量为4.4%(相对于单体质量)及搅拌转速为500r.min-1的条件下,聚合过程稳定性好,树脂粒径适中、饱和吸水率高、吸水速度快。     

反相悬浮聚合法制备腐殖酸高吸水性树脂进展

反相悬浮聚合法制备腐殖酸-聚丙烯酸高吸水性树脂(HA-PAA),论述了高吸水性树脂的结构及复合机理,阐明了高吸水性树脂的应用领域。腐植酸树脂具有良好的吸附、吸水、降滤失和抗温、抗盐性能,得到了广泛的应用。随着腐植酸树脂研究的进展,其应用前景将更加广阔。     

反相悬浮法制备粘土复合高吸水性树脂

以丙烯酸和蒙脱土为主要原料,采用反相悬浮法合成了聚丙烯酸钠/蒙脱土复合高吸水性树脂,研究了交联剂用量、蒙脱土用量等因素对树脂吸液性能的影响,确定了最佳实验条件,在此条件下制备的复合树脂对去离子水和0.9%NaC l水溶液的吸水率分别为800g/g和92g/g,适量蒙脱土的加入可提高吸水性树脂的保水性能,FTIR初步表明蒙脱土与聚丙烯酸钠之间发生了交联反应。     

反相悬浮法制备AA—AM／蒙脱土农用复合吸水性树脂

以丙烯酸(AA)、丙烯酰胺(AM)、蒙脱土(MMT)、尿素为原料,采用反相悬浮法制备了农用复合吸水性树脂,研究了单体配比、油水比、蒙脱土用量对树脂吸水性的影响,并考察了树脂的保水性和缓释性.结果显示,当单体配比为2∶1,油水比为3∶1,蒙脱土用量为10%时,树脂具有较好的吸水性和保水性,并能使得尿素缓慢释放.     

反相悬浮聚合法合成大粒径高吸水性树脂研究

使用失水山梨醇单油酸酯S20和大分子分散剂马来酸接枝聚乙烯蜡1105A,考察了分散剂种类、各相比例以及搅拌等因素对反相悬浮聚合反应合成高吸水性树脂的影响。结果表明:在搅拌速率400～500 r·min^-1、水相和油相体积比为1∶2的条件下,以过硫酸铵为引发剂,复合使用S20和1105A,获得了粒径150～600μm范围的"覆盘子"形貌高吸水性树脂,吸水速度在5 min之内可以达到饱和。     

硬脂酸/二氧化硅复合相变储热材料制备及性能研究

采用“溶胶-凝胶”工艺制备出具有不同硬脂酸质量分数的硬脂酸/二氧化硅复合相变储热材料,运用SEM、XRD和DSC等手段对复合相变储热材料的结构与性能进行了表征和测试。复合相变储热材料是硬脂酸嵌入到二氧化硅三维纳米网孔中形成的,其相变温度和相变潜热均随硬脂酸质量分数的增加而增大,且相变温度低于纯硬脂酸,相变潜热与对应质量分数下的硬脂酸相当。实验结果表明,硬脂酸/二氧化硅复合相变储热材料具有储热密度大、性能稳定以及导热系数较高等优点。     

用煤系高岭土制备超强吸水复合材料的研究

经900℃煅烧后的煤系高岭土与聚丙烯酸钠合成的超强吸水复合材料吸水性能好,成本低。当煅烧煤系高岭土量为丙烯酸单体质量的50％,中和度为90％,引发剂量为0．3％,交联剂量为0．025％时,所制得复合材料吸收蒸馏水率可达940g／g,吸自来水可达325g／g。     

Nanosize Polyacrylamide/SiO2 Composites by Inverse Microemulsion Polymerization

Nanosize polyacrylamide/silica (PAM/SiO₂) composites were prepared by water- in-oil (W/O) microemulsion process. In this system, aqueous solution of acrylamide containing disperse 10 nm size silicon dioxide was used as the dispersed phase of the microemulsion while the dispersion medium was sodium bis (2-ethylhexyl) sulfosuccinate (AOT)/toluene solution. The size of the synthesized PAM/SiO₂ nanocomposites was 38–76 nm as determined by dynamic light scattering (DLS). The incorporation of nanosize silica filler reduces the particle size of PAM latex. It had also been found that the size of composite particles decreases with increasing filler loading along with better polydispersity. The presence of silica particles in the polymer latex particles and interaction of polymer chains with silica particles in hybrid nanocomposites were characterized by Fourier transform infra red spectrophotometry (FTIR), thermogravimetry analysis (TGA) and differential scanning calorimetry (DSC). The TGA results showed improved thermoresistance and high thermal stability behavior of hybrid composites. The DSC measurements revealed that the incorporation of filler favors crystallization, increases the enthalpy of melting and thermal stabilization of the synthesized composite particles. A scanning electron microscope (SEM) was used to study the morphology and topography of the prepared nanocomposites.     

聚乙烯/凹凸棒石纳米复合材料的研究

采用原位聚合法制备聚乙烯／凹凸棒石纳米复合材料,结果表明：凹凸棒石的纳米级晶须可在聚乙烯树脂中能够较好地分散,聚乙烯在凹凸棒石表面绞缠,并且在不同晶须间绞缠,形成独特的交联网状结构一“有机／无机凝胶”;纳米复合材料能够显著提高聚乙烯的抗冲强度。     

Study on starch-graft-acrylamide/mineral powder superabsorbent composite

A novel starch-graft-acrylamide/mineral powder superabsorbent composite with water absorbency about 4000 times is synthesized by graft-copolymerization reaction among acrylamide, potato starch and mineral ultrafinepowder, followed by hydrolysis with sodium hydroxide. It is found that the composite doped with kaolinite powder possess higher water absorbency than those doped with bentonite or sercite powder, since the kaolinite powder can moderately disperse in the water and cross-link with acrylamide and starch. By controlling the amount of NaOH and reaction time during saponification process, the hydrophilic groups on the composite can be adjusted, it is found that the collaborative absorbent effect of −CONH₂, −COONa and −COOH groups is superior to that of single −CONH₂, −COONa or −COOH group. By the IR characterization, the polymerization reaction mechanism and structure of the composite is supposed, the mineral ultrafinepowder as a cross-linking point play an important role in the formation of network structure of the superabsorbent composite.     

高岭土复合耐盐型高吸水性树脂的合成

以丙烯酸(AA)、丙烯酰胺(AM)、甲基丙烯酰氧乙基三甲基氯化铵(DMC)为原料,通过反相悬浮法制得具有阳离子、阴离子、非离子单体和高岭土复合的耐盐型高吸水树脂。选用环己烷作为油相,过硫酸钾为引发剂,N,N-亚甲基双丙烯酰胺为交联剂,Span 60为悬浮剂,研究了丙烯酸中和度、高岭土用量、DMC用量、引发剂用量、交联剂用量、反应温度对树脂吸液性能的影响。并用红外光谱和扫描电镜对其结构进行了表征。在最佳工艺条件下,耐盐型吸水树脂对蒸馏水和生理盐水的吸液率分别为1 827 g/g和146 g/g。     

AM/AQ反相悬浮聚合反应中分散剂的研究

采用反相悬浮聚合方法,以环己烷为连续相,无水亚硫酸钠和偶氮二异丁腈为引发剂,以丙烯酰胺（AM）和功能性阳离子型单体氯化[N、N、N-三甲基乙醇丙烯酸酯]盐（AQ）为合成单体,合成颗粒状的阳离子型高分子絮凝剂.研究了分散剂的HLB值、种类和质量分数等因素对聚合物的影响.结果表明,选择由Span60和Span80组成的混合分散剂,其HLB值为4.5时,反应体系最稳定;分散剂的质量分数为2.5%时,聚合物黏度最大,产率最高.     

Study on superabsorbent composites XIX. Synthesis, characterization and performance of chitosan-g-poly (acrylic acid)/vermiculite superabsorbent composites

A novel chitosan-g-poly (acrylic acid)/unexpanded vermiculite (CTS-g-PAA/UVMT) superabsorbent composite was prepared by graft polymerization among chitosan (CTS), acrylic acid (AA) and unexpanded vermiculite (UVMT) in aqueous solution. The effect of polymerization variables, including the content of crosslinker, initiator and UVMT, the weight ratio of AA to CTS, the reaction temperature, time and drying method, on water absorbency were studied. The swelling rate of the superabsorbent composite in distilled water was also investigated. The results from FTIR spectra showed that CTS and UVMT participated in graft polymerization reaction with AA. Introducing UVMT into the CTS-g-PAA polymeric network could form a loose and more porous structure by the SEM analysis, and the polymerization reaction is performed on the surface of UVMT micropowders from the results of XRD. The introduced UVMT enhanced the swelling rate and the water absorbency of CTS-g-PAA/UVMT superabsorbent composite.     

凹凸棒土/石墨复合材料电极的制备及性质

以酸化处理的凹凸棒土粉和膨胀处理的石墨粉为原料、环氧树脂为粘合剂,制得凹凸棒土/石墨复合材料电极。采用扫描电镜、红外光谱等对其形貌和结构进行表征。探讨了电极材料类型、富集时间、平行测定次数对模拟苯酚废水峰电流的影响。研究结果表明,凹凸棒土/石墨复合材料电极比普通石墨电极对峰电流的响应更明显,且稳定性好,无二次污染。     

废纸纤维素/SiO2复合气凝胶的性能

对废纸纤维素进行处理，以甲基三甲氧基硅烷（MTMS）作为硅源，制备纤维素/SiO₂复合水凝胶，经过冷冻干燥得到性能良好的纤维素/SiO₂复合气凝胶。利用扫描电镜（SEM）、接触角测量仪及热重分析（TGA）等对制得的气凝胶进行了表征测试。结果显示材料由大孔、介孔、微孔组成，最低密度为0.107 g/cm³，具有较好的疏水性能，静态疏水接触角可达148.5°，力学性能良好，可实现50%范围内压缩后100%恢复，材料具备良好的吸附性能，吸附油污可达到本身质量的12.7倍，热稳定性提高。在处理有机废水，尤其是水体油污方面有着广阔的应用前景。