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单分散交联聚苯乙烯微球HPLC固定相的合成 总被引:3,自引:0,他引:3
用分散聚合物合成了单分散聚苯乙烯微球种子,然后用种子聚合法合成了交联的聚苯乙烯向球,其粒径范围可控制在2μm~4μm,考察了反应条件对微球粒径和粒径分布的影响,确定了最佳合成条件,初步考察了交联微球的HPLC性能。 相似文献
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用粒径约0.5微米季胺化单分散交联聚苯乙烯胶乳与粒径为5~30微米磺化交联聚苯乙烯共聚物微球藉库伦力附聚得到了阴离子交换树脂微球,并对磺化深度,基球和胶乳的粒径比以及交联度等对阴离子交换树脂附聚微球色谱性能的影响进行了分析。用这种阴离子交换树脂附聚微球作为HPIC分离柱的填料;用自制的全多孔强阳离子交换树脂YSG-SO_3H为抑制柱填料,仅用10厘米长的分离柱在约27分钟内即可使F~-、Cl~-、No_2~-、HPO_4~-、Br~-、No_3~-、及SO_4~-等阴离子混合样按顺序全分离。 相似文献
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种子溶胀法制备单分散高交联聚苯乙烯微球 总被引:2,自引:0,他引:2
以分散聚合法制得平均粒径为1.80μm的聚苯乙烯微球为种子,与溶胀剂和单体、交联剂的混合物经二步溶胀聚合法,制备了单分散高交联聚苯乙烯微球。讨论了单体浓度和醇水比对种球的影响,以及溶胀剂的种类、溶胀剂浓度、交联剂浓度、溶胀温度和搅拌速度等因素对交联聚苯乙烯微球粒径及分散系数的影响。用扫描电子显微镜、离心式粒度分析仪及DSC分析测试技术对微球的外观形貌、粒径大小及分布和玻璃化转变温度分别进行了表征。结果表明,当溶胀剂质量分数为25%、交联剂质量分数为23%、溶胀温度30℃、搅拌速度为150r/min时,可制得平均粒径为6.20μm且单分散性较好的高交联聚苯乙烯微球。 相似文献
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功能高分子微球研究分散聚合法合成μ级聚苯乙烯微球 总被引:12,自引:1,他引:11
微米级聚苯乙烯微球广泛用于临床分析、生物医学、胶体研究等领城,亦可作为电子显微镜、光散射、沉降法等测定微小物体绝对长度的基准物、色谱柱填料等。用分散聚合法可以制得微米级单分散聚苯乙烯微球。本文通过对分散聚合条件和配方的研究,以水和醇为分散介质,分子量4000的聚乙二醇为稳定剂,过氧化苯甲酰为引发剂,合成了粒径为3至4μm的单分散聚苯乙烯微球。在分散聚合体系中,随着有机溶剂、单体、引发剂等用量的增加,胶乳粒径增大,粒径分布变宽。随着稳定剂、表面张力调节剂等用量的增加,胶乳粒径减小,粒径分布变窄。有机溶剂种类改变以及聚合反应温度变化,胶乳粒径也发生变化。 相似文献
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非多孔树脂的高效液相色谱填料及其对蛋白质的分离性能 总被引:1,自引:0,他引:1
合成并表征了粒度为7μm的基于聚(甲基丙烯酸甲酯/二乙烯苯)(PMMA/DVB)和在丙烯酸丁酯/二乙烯苯)(PBMA/DVB)的两种非多孔树脂。该类树脂可用作高效液相色谱填料的基质,也可直接用于色谱分离。PMMA/DVB树脂对于蛋白质的分离具有疏水怀相互作用色谱填料的性能,而PBMA/DVB树脂由于其强疏澡性则对于蛋白质的反相色谱是适宜的。基质树脂经NaOH溶液水解,就转化成表面含羧甲基的并具有相 相似文献
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单分散高纯硅胶色谱柱填料的制备 总被引:1,自引:0,他引:1
在氨水和氨气催化下使单晶硅粉水解, 合成了单分散、高纯的纳米二氧化硅水溶胶; 再利用聚合诱导胶体凝聚法(PICA)制备单分散脲醛二氧化硅复合微球, 经过高温煅烧后得到球形硅胶色谱柱填料. 通过电感耦合等离子-质谱(ICP-MS)、电子显微镜和BET比表面积测试等手段对球形硅胶的纯度、粒径分布及比表面积进行了表征, 并通过色谱分离对硅胶填料的性能进行了评价. 实验结果表明, 该方法合成的色谱柱填料具有纯度高、粒径分布均匀、机械强度高及分离能力强等优点. 相似文献
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单分散、大粒径聚苯乙烯微球的制备 总被引:23,自引:0,他引:23
以聚乙烯基吡咯烷酮为分散剂、偶氮二异丁腈为引发剂、醇/水混合物为分散介质进行了苯乙烯的分散聚合,讨论了初始单体浓度、分散剂用量、引发剂浓度、分散介质组成和反应温度等反应条件对所得聚合物颗粒直径和直径分布的影响.通过大量的试验,筛选出了较为理想的分散聚合的条件及配方,制备出了粒径为48μm的单分散聚苯乙烯微球.然后,以分散聚合所制得的聚合物颗粒为种子,用动力学溶胀法制成了粒径增大近四倍的单分散、大粒径聚苯乙烯微球,并讨论了滴水速度和补加分散剂对溶胀的影响 相似文献
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Cline Farcet Julien Nicolas Bernadette Charleux 《Journal of polymer science. Part A, Polymer chemistry》2002,40(24):4410-4420
The controlled free‐radical homopolymerization of n‐butyl acrylate was studied in aqueous miniemulsions at 112 and 125 °C with a low molar mass alkoxyamine unimolecular initiator and an acyclic β‐phosphonylated nitroxide mediator, N‐tert‐butyl‐N‐(1‐diethylphosphono‐2,2‐dimethylpropyl) nitroxide, also called SG1. The polymerizations led to stable latices with 20 wt % solids and were obtained with neither coagulation during synthesis nor destabilization over time. However, in contrast to latices obtained via classical free‐radical polymerization, the average particle size of the final latices was large, with broad particle size distributions. The initial [SG1]0/[alkoxyamine]0 molar ratio was shown to control the rate of polymerization. The fraction of SG1 released upon macroradical self‐termination was small with respect to the initial alkoxyamine concentration, indicating a very low fraction of dead chains. Average molar masses were controlled by the initial concentration of alkoxyamine and increased linearly with monomer conversion. The molar mass distribution was narrow, depending on the initial concentration of free nitroxide in the system. The initiator efficiency was lower than 1 at 112 °C but was very significantly improved when either a macroinitiator was used at 112 °C or the polymerization temperature was raised to 125 °C. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 4410–4420, 2002 相似文献
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Kevin M. Burridge Nethmi De Alwis Watuthanthrige Camryn Payne Richard C. Page Dominik Konkolewicz 《Journal of polymer science. Part A, Polymer chemistry》2021,59(21):2530-2536
An enduring question is: what is the simplest and easiest way to obtain tailored polymers? This communication explores a robust photoiniferter polymerization with only two active ingredients that requires no prior deoxygenation and can be performed on the milliliter scale or sub-milliliter scale. Rather than leaving headspace in the polymerization vessel or scaling reactions up to fill the vessel, this approach fills the headspace of the reaction vessel with mineral oil or inert solvents. This approach can also be applied to polar monomers in aqueous media, using oil as the inert solvent, or to hydrophobic monomers with water as the inert solvent. This method removes enough ambient oxygen that the photoiniferter reaction proceeds with no deoxygenation step, and achieves high conversion and good molecular weight control in 10–20 h in both aqueous and organic solvents. Complex polymer architectures such as multiblock copolymers and gradient polymers were successfully synthesized by this approach. 相似文献
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原子转移自由基聚合(ATRP)应用于乳液聚合体系的主要挑战在于如何同时保证乳液的稳定性和聚合反应的可控性。本文主要对乳液ATRP体系中影响聚合反应可控性和乳液稳定性的各种因素、乳液ATRP的机理和乳液ATRP的应用等方面进行了综述。表面活性剂亲水亲油性及其亲水亲油基团的化学性质、催化剂/配体在油/水两相之间的分配行为、引发剂的溶解性、反应温度以及各组分的浓度是影响反应可控性和乳液稳定性的主要因素。各组分在油/水两相中的分配行为使得乳液ATRP的机理比传统乳液聚合更加复杂。乳液原子转移自由基聚合结合了活性自由基聚合和乳液聚合的优点,在理论研究和工业生产上具有很大的应用前景。 相似文献
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Reverse iodine transfer polymerization (RITP) is a new controlled radical polymerization technique based on the use of molecular iodine I2 as control agent. This paper aims at presenting the basics of RITP and the strategy that we have followed for the development of this process in the past three years, from the validation in homogeneous solution polymerization up to recent results in heterogeneous aqueous polymerization processes. Typical examples of RITP of butyl acrylate in emulsion and RITP of styrene in miniemulsion are discussed. 相似文献