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反相悬浮聚合分散剂的合成及性能 总被引:8,自引:0,他引:8
聚丙烯酸(钠)的吸水速度快,吸水量大,通常在有机介质环己烷、戊烷、(甲基)环戊烷中进行反相乳液聚合法生产,但一般只能获得颗粒细小的粉末状树脂,在介质中沉降速度慢,工程上易起粉尘危害.吸水树脂颗粒细小也影响树脂性能[1],采用反相悬浮聚合法合成聚丙烯酸... 相似文献
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聚丙烯酰胺/凹凸棒土(Attapulgite)纳米复合高吸水性树脂的制备与性能 总被引:6,自引:0,他引:6
高吸水性树脂是一种新型功能高分子材料,由于其优越的吸水保水性能,已在农林园艺和生理卫生用品等领域得到了应用,但它仍然存在抗盐性能差、吸水后凝胶强度低等不足.近年来,有机.无机复合高吸水性树脂因具有较高的吸水性能和低廉的生产成本而受到了广泛的关注,使用的无机粘土主要有高岭土、蒙脱土和凹凸棒土等.粘土具有活性基团和键合点,加入到高吸水性树脂三维网络中可以改善树脂的网络结构,提高其综合性能.凹凸棒土是一种含水富镁铝的层链状硅酸盐,相对于其它粘土,它具有很好的抗盐、吸附和胶体性能。 相似文献
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共聚类吸水树脂综合应用性能研究 总被引:2,自引:0,他引:2
以丙烯酸烯丙酯为交联剂合成了丙烯酸和丙烯酰胺共聚类吸水树脂,并对该吸水树脂的综合稳定性(耐热性、耐寒性、耐光性)进行了研究.对树脂凝胶溶胶含量、土壤保水性、树脂对去离子水、生理盐水、人工血、人工尿的吸收能力及树脂的膨胀动力学和热分解动力学作了较为全面的研究.确定了膨胀动力学参数及热分解反应动力学参数, 结果表明:所合成树脂吸水膨胀过程中膨胀指数0.5〈n〈1,属于non-Fikian扩散,吸水树脂的热解过程分为两个阶段,都属于一级反应,以丙烯酸烯丙酯作为交联剂合成的丙烯酸和丙烯酰胺共聚类吸水树脂具有良好的综合应用性能. 相似文献
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交联剂分子量对高吸水性树脂性能的影响 总被引:9,自引:0,他引:9
通过丙烯酰氯对聚乙二醇的封端反应合成了一系列分子量不同、结构类似的交联剂———聚乙二醇二丙烯酸酯 (PEGDA) ,并用于聚丙烯酸高吸水性树脂的制备 .运用FTIR对PEGDA进行了分析 .吸水性能实验结果表明 ,交联剂的分子量越大 ,则高吸水性树脂的吸水倍率越高 ,吸水速率越大 ,而相对吸水速率降低 .同时 ,PEGDA与常用的交联剂N ,N′ 亚甲基双丙烯酰胺 (MBA)相比 ,前者制备的高吸水性树脂的吸水倍率远高于后者 ;线型可溶性聚合物及残留单体的含量 ,前者也低于后者 相似文献
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以锆盐为交联剂的耐盐型聚乙烯醇高吸水树脂的合成 总被引:6,自引:0,他引:6
以锆盐为交联剂的耐盐型聚乙烯醇高吸水树脂的合成刘德荣,颜杰,刘习奎,刘兴勇(四川轻化工学院化学工程系自贡643033)关键词聚乙烯醇锆盐络合树脂,耐盐型聚乙烯醇吸水树脂,磷酸化聚乙烯醇本研究采用两种方法在聚乙烯醇中引人磷酸根.(l)聚乙烯醇和磷酸反应... 相似文献
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多功能高分子植物生长剂制备及其应用 总被引:1,自引:0,他引:1
高吸水树脂以其吸水性强、吸水速度快、保水能力强等优点。广泛用于农业、园林、卫生材料等方面[1~4] 。本文制备的高吸水树脂是以过硫酸钾为引发剂 ,淀粉为原料 ,使之接枝并适度交联。交联产物经醇解、脱水、干燥、粉碎即得吸水倍数大于 70 0倍的吸水树脂 ,并对主要影响因素进行正交优化 ,在最佳条件下制得的吸水树脂配以一定量有效微生物群 ,制得具有吸水、保水、促生长及可降解的多功能植物生长剂。1 实验部分1 1 主要试剂及仪器玉米淀粉 (市售 ,1 0 5℃下烘干 ,干燥保存 )、过硫酸钾 (CP)、丙烯酸 (CP ,用前减压蒸馏精制 )、N … 相似文献
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以过硫酸铵(APS)为引发剂,N,N′-亚甲基双丙烯酰胺(MBA)为交联剂,采用水溶液聚合法制备了碳纳米管/聚丙烯酸钠高吸水树脂。系统考察了碳纳米管质量分数、引发剂、交联剂和聚合温度对树脂吸水性能的影响。结果表明,以单体丙烯酸质量为基准,当交联剂,引发剂和碳纳米管质量分数分别为0.04%、0.3%和0.3%,聚合温度75℃时,所合成树脂的吸水性能最佳。添加碳纳米管后树脂表面粗糙和形成孔结构导致了其吸水性能的变化,使得碳纳米管/聚丙烯酸钠的吸水量和吸水速率明显提高,其吸去离子水和生理盐水能力分别达到1423和104g/g。该树脂重复吸水5次后,其吸水能力为1081.5g/g,达到最大吸水倍数的76.0%。 相似文献
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Yan QZ Zhang WF Lu GD Su XT Ge CC 《Chemistry (Weinheim an der Bergstrasse, Germany)》2005,11(22):6609-6615
Recently, a considerable amount of research has centered on uniquely structured polymers synthesized through self-propagating frontal polymerization. The obtained polymer materials have better features than those obtained by using the classical batch route. The additional advantages are short reaction times and low cost. This work describes the first frontal polymerization synthesis of a graft copolymer superabsorbent hydrogel of acrylic acid onto starch at high monomer and initiator concentration. The effects of varying the relative amounts of the reaction components on the most relevant parameters relating to frontal polymerization were explored. The front velocity dependence on initiator concentration could be fit to a power function. The temperature profiles were found to be very sharp with a maximum temperature below 150 degrees C, which was responsible for high monomer conversion. The ultimate properties of the product appear to depend on the polymerization front velocity and the temperature. The high-temperature and rapid temperature increase at the polymerization front led to products with interconnected porous structures caused by the evaporation of water. So, a fast-swelling, highly absorbing hydrogel with respect to batch polymerization was obtained. 相似文献
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Huan Shao Cai‐Feng Wang Su Chen Chen Xu 《Journal of polymer science. Part A, Polymer chemistry》2014,52(7):912-920
We report the facile synthesis of poly(VI‐co‐MAA) superabsorbent polyampholytic hydrogels (VI = N‐vinylimidazole, MAA = methacrylic acid) via plasma‐ignited frontal polymerization (PIFP). On igniting the top surface of the reactants with air plasma, frontal polymerization occurred and poly(VI‐co‐MAA) hydrogels were obtained within minutes. The preparation parameters were investigated, along with swelling capacity, morphology, and chemical structures of poly(VI‐co‐MAA) hydrogels. Interestingly, the hydrogels are superabsorbent in water and show ampholytic characteristic toward pH. Moreover, the hydrogels are able to capture cationic dyes through electrostatic interaction, offering the potential for further development as dye adsorbents for water purification. In addition, nanocomposite hydrogels were obtained by embedding quantum dots (carbon dots or CdS nanocrystals) into the polymer matrix, which endows the nanocomposite hydrogels with favorable fluorescence and potential applications in bioimaging and biosensing. The results indicate that FP can be applied as an alternative means for facile synthesis of multifunctional hydrogels with additional efficiency and energy‐saving. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 912–920 相似文献
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Jing Li Xia Zhang Jian Chen Jun Xia Meihu Ma Bin Li 《Journal of polymer science. Part A, Polymer chemistry》2009,47(13):3391-3398
Konjac glucomannan‐graft‐acrylic acid polymers, used as superabsorbent polymers (SAPs), were synthesized by frontal polymerization (FP). The features of front propagation including front velocity and maximum temperature (Tmax) were influenced by the amount of glucomannan, initiator, and environment temperature. The graft copolymer was characterized by FTIR, DSC, and SEM. The amount of crosslinking agent mainly determined the crosslinking degree of SAPs that would affect the water absorbency and microstructure. Water absorbency of SAP was also investigated and most of them displayed high water absorption rate. The aforementioned results allow us to conclude that FP can be considered as a promising method to fabricate SAP for its excellent advantages. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 3391–3398, 2009 相似文献
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Frontal polymerization (FP) is a mode of converting a monomer into a polymer via a localized reaction zone that propagates through the monomer. In this study, segmented polyurethane was successfully prepared by FP. The reactants, poly (propylene oxide) glycol, 2, 4-toluene diisocyanate and 1,4-butanediol and the catalyst stannous caprylate, were mixed together at an initial temperature in the presence of dimethylbenzene (as the solvent). The reactions were thermally ignited at one end of the tubular reactor, and the resultant hot fronts propagated throughout the reaction reactor. No further energy was required for polymerization to occur. The effect factors of front velocity, stannous caprylate concentration and temperature on the FP, along with comparison of FP with bulk polymerization, were thoroughly investigated. Fourier transform infrared and differential scanning calorimetry were employed to characterize polyurethane (PU). The polymer materials obtained by FP displayed features similar to those obtained by batch polymerization. The reaction time of FP for preparing PU was lower than that of BP. 相似文献
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Li Chen Ting Hu Huan Yu Su Chen John A. Pojman 《Journal of polymer science. Part A, Polymer chemistry》2007,45(18):4322-4330
We report the first synthesis of poly (N‐methylolacrylamide) (PNMA) via free‐radical frontal polymerization (FP) with solid monomers at ambient pressure. The appropriate amounts of reactants (N‐methylolacrylamide) (NMA) and initiator (ammonium persulfate) were mixed together at ambient temperature without solvent. FP was initiated by heating the wall of the tube with a soldering iron, and the resultant hot fronts were allowed to self‐propagate throughout the reaction vessel. Once initiated, no further energy was required for polymerization to occur. To suppress the fingers of molten monomer, a small amount of nanosilica was added. We also produced PNMA with dimethyl sulfoxide (DMSO) or N‐methyl‐2‐pyrrolidone, as solvent by FP, to study the macrokinetics in FP of PNMA without fillers. The front velocity and front temperature dependence on the ammonium persulfate and N‐methyl‐2‐pyrrolidone concentration were investigated. The polymer was analyzed by thermogravimetric analysis. Results show that without postpolymerization solvent removal, waste production can be reduced. Solvent‐free FP could be exploited as a means for preparation of PNMA with the potential advantage of higher throughput than solvent‐based methods. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4322–4330, 2007 相似文献
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Chao Yu Jin Zhou Cai‐feng Wang Li Chen Su Chen 《Journal of polymer science. Part A, Polymer chemistry》2011,49(24):5217-5226
Atmospheric air plasma was created and applied in the frontal polymerization (FP) of fabricating poly(HPA‐co‐VeoVa 10) amphiphilic gels (HPA = 2‐hydroxypropyl acrylate, VeoVa 10 = vinyl versatate) with enhanced physicochemical properties. In plasma‐ignited frontal polymerization (PIFP), once ignited by air plasma, no further energy or treatment was required for the following polymerization. In this system, the comparison between PIFP and thermal frontal polymerization (TFP) was conducted and observed that PIFP and TFP differ considerably in terms of swelling capacity, morphology and component distribution of the products. This finding is of great importance that the simultaneous generation of active radicals in the initial stage can spread throughout reactant and anchor on the synthetic polymer with the assistance of FP. More interestingly, the PIFP‐synthesized copolymer possesses remarkable selective absorption towards organic solvents, which can be facilely manipulated by varying the weight ratios of HPA/VeoVa 10. Obviously, these polymer products could serve as an “organic solvent scavenger” in the field of industrial wastewater treatment. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
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A novelty method, frontal polymerization (FP), was employed to directly produce a series of polyacrylamide (PAM), poly(N-isopropylacrylamide) (PNIPAM) and acrylamide-N-isopropylacrylamide copolymer macroporous monoliths. Field emission scanning electronic microscope and mercury intrusion method were adopted to measure some parameters of these monoliths, such as frame, pore size distribution as well as porosity. Effects of types of monomer, thicker and surfactant on porous structure of monoliths were studied. A variety of pore morphologies, such as honeycomb, sheet and grid, was obtained by changing types of reactants. The above results allowed us to conclude that FP can be exploited as an alternative means of macroporous polymer monolithic synthesis with the additional advantages of high velocity, environmental safe and energy reduction. 相似文献
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Morteza Ziaee Mostafa Yourdkhani 《Journal of polymer science. Part A, Polymer chemistry》2021,59(15):1732-1739
In thermal frontal polymerization (FP), ambient temperature and staging conditions highly affect the resin behavior and front properties. This study describes the effect of staging conditions and resin reactivity on frontal ring opening metathesis polymerization of dicyclopentadiene in presence of phosphite-inhibited second-generation Grubbs catalyst. An experimental setup is designed to characterize and understand the effect of inhibitor concentration, incubation time, and incubation temperature on front velocity, activation time, and front temperature of the FP reaction. The results reveal that front properties are influenced by various factors, including available energy density of resin, stability of catalyst-inhibitor complex, resin temperature, and resin viscosity. An increase in staging temperature results in lower pot lives but faster gelation process and activation of FP reaction. Additionally, increasing the inhibitor concentration leads to slower fronts, higher activation times, and longer pot lives. The results of this study can be extended to other FP systems and can be used in design of new manufacturing processes and applications using FP. 相似文献