单分散亲水性微米级聚合物微球的合成研究

本文研究了分散荆的种类与用量、初始单体浓度、共聚单体组成、以及分散介质的组成对素水性单体甲基丙烯酸羟丙酯的分散聚合稳定性及对聚合物微球的尺寸及尺寸分布的影响规律．确定了合适的分散剂及分散介质组成．成功地进行了甲基丙烯酸羟丙酯的分散聚合，得到了微米级、单分散性聚合物微球。     

单分散亚微米级聚合物微球的研究进展

本文综述了单分散亚微米级聚合物微球的自由基聚合主要制备方法,包括分散聚合、RAFT分散聚合、乳液聚合和无皂乳液聚合,讨论了溶剂、引发剂、单体、分散剂、乳化剂、搅拌和温度的选择及其对聚合物微球粒径和单分散性的影响以及粒径控制机理.     

涂料用具有不同交联区域的粒子的聚合物分散体的制备

本发明涉及聚合物分散体的制备及应用,该分散体含聚合物粒子（粒子内具有不同交联区域,其用于涂料配制及应用于多种底材上）。所述聚合物分散体的制备是通过将2种有不同单体-交联剂含量的单体混合物乳液聚合,在聚合过程中通过控制第二种单体混合物加入和整个聚合条件可改变其浓度。     

单分散苯胺分子印迹聚合物微球的合成与表征

以甲基丙烯酸为单体、二乙烯基苯为交联剂、苯胺为模板分子,利用沉淀聚合法通过改变溶剂等条件制备了单分散苯胺分子印迹聚合物微球。通过扫描电子显微镜表征微球表面形貌幵测量微球尺寸,通过纳米粒度分析仪验证微球单分散性。经气相色谱表征,该分子印迹聚合物对苯胺最大静态吸附量为12.98 mg/g,具备对苯胺分子的特异性识别能力。     

二步种子溶胀法制备氯霉素分子印迹聚合物微球及其识别性能

以聚苯乙烯乳液为种球、氯霉素为模板分子、甲基丙烯酸为功能单体、二甲基丙烯酸乙二醇酯为交联剂,采用二步种子溶胀法制备了单分散氯霉素分子印迹聚合物微球(MIPMs).通过扫描电镜(SEM),考察了溶胀比、搅拌速度、水油比、交联剂用量、分散荆用量等对MIPMs形态,粒径大小及粒径分布的影响.并用静态吸附实验考察了微球的吸附识...     

分散聚合及单分散聚合物微球制备技术

分散聚合是一种新的聚合方法 ,反应开始前 ,单体、引发剂和分散剂均溶解在介质中 ,随着反应的进行 ,当聚合物链达到临界值时便会从介质中分离出来 ,并借助于分散剂稳定地悬浮在介质中。分散聚合方法已被应用于许多领域 ,如涂料工业、生物工程、医学、信息产业、化学工业等。介绍了分散聚合及单分散聚合物微球制备技术的进展 ,并对其聚合机理及聚合反应影响因素进行了概述。     

单分散聚合物微球的制备及应用

单分散聚合物微球是一类新型的高聚物材料,其制备方法多样且应用广泛。本文主要介绍了单分散聚合物微球常用的制备方法及其应用。单分散聚合物微球因具有粒径均一、表面可修饰等特点,在药物载体、生物分离、光子晶体等许多领域有着广泛的应用,引起国内外学者越来越多的关注。     

单分散聚合物微球的制备及功能化研究进展

综述了单分散聚合物微球常用的制备方法(乳液聚合法、种子聚合法、分散聚合法、沉淀聚合法、悬浮聚合法和膜乳化法等),介绍了单分散聚合物微球的功能化研究进展,包括磁性微球、多孔微球、温度/pH响应微球、阳离子微球以及微球官能团化等等。最后提出了多种聚合方法的相互结合是制备功能性单分散聚合物微球的一大趋势,开发多功能的单分散聚合物微球、实现批量生产是其近期的重点研究方向。     

纳米二氧化钛及其被覆聚丙烯酸酯分散液分析

聚合物分散液智能开关,全息材料等领域具有广阔的应用前景,激光全息技术飞速发展,使得激光全息聚合物分散液材料产生,其原理是利用光引发单体聚合,其性能主要取决于体系的相分离程度及折射率对比度。采用钛酸四丁酯为先驱物,冰醋酸为抑制剂,制备纳米二氧化钛溶胶,将单体滴加到纳米二氧化钛溶胶中,过硫酸钾单体在纳米二氧化钛溶胶粒子发生聚合反应,得到被覆聚丙烯酸酯分散液,使用动态光散仪分析纳米二氧化钛溶胶粒径,利用投射电镜观察被覆聚丙烯酸酯分散液形貌,探讨最佳溶胶单体混合液pH值,及纳米二氧化钛溶胶质量分数对被覆聚丙烯酸酯分散液成膜性能的影响,表明制备纳米二氧化钛溶胶平均粒径为263nm,包裹纳米二氧化钛溶胶粒子最佳反应温度为75℃,溶胶单体混合液pH值为8,溶胶质量分数最佳为20%。     

接枝型水性聚合物分散剂的催化链转移聚合制备及其炭黑分散能力研究

应用催化链转移聚合技术合成末端带有可聚合双键的大分子单体,然后大分子单体进一步与主链单体共聚制备接枝聚合物,并通过定量酸性水解得到支链亲水、主链疏水的两亲接枝聚合物。同时系统研究了该聚合物的主链与侧链的分子量大小、主链锚定基团种类与浓度等因素对其在水性体系中炭黑分散能力的影响,为分散剂的结构优化奠定基础;所优选结构的分散剂其炭黑分散能力与进口分散剂Disperbyk-190相当。     

引发剂和活化剂用量对MC尼龙性能的影响

通过改变催化剂(包括引发剂和活化剂)用量合成四个系列MC尼龙,研究了引发剂和活化剂用量的变化对MC尼龙合成、结构和力学性能的影响。实验结果表明：引发剂和活化剂的用量对MC尼龙的对聚合速率、单体转化率、结晶度和结晶温度有一定的影响,同时也对拉伸强度、缺口冲击强度、弯曲强度和弯曲模量影响很大。     

Effects of molecular weight on the dynamic mechanical and rheological properties of anionically polymerized polyamide 6 containing nanofiber

Anionic ring‐opening polymerization of ε‐caprolactam leads to the formation of polyamide 6 (PA6). This reaction takes place at a significantly faster rate and gives a narrower molecular‐weight distribution than those obtained with other techniques. Because of this advantage, anionic polymerization of PA6 during melting was investigated in this work. In an internal mixer, PA6 was prepared via the melt polymerization of ε‐caprolactam as monomer with sodium caprolactam as a catalyst and hexamethylene diisocyanate as an activator. The effects of various concentrations of catalyst and activator on the rate of reaction and the amount of residual monomer were determined. Also, the physical and mechanical properties of PA6 prepared in this way and commercial PA6 prepared via hydrolytic processing were determined by differential scanning calorimetry and dynamic mechanical thermal analysis, as well as tensile, impact, and rheological tests. The experimental results showed that the composition which included 3% of catalyst and 3% of activator gave better properties than the other formulations. These conditions led to the lowest residual monomer content and better mechanical properties, as well. Another novel aspect of this investigation was nanofiber formation during the melt polymerization. The nanofibers had lower molecular weights than the matrix and thus created a special crystal structure different from that of the matrix. Mechanical property measurements showed that PA6 prepared by using this technique and the aforementioned formulation was similar to the commercial PA6. J. VINYL ADDIT. TECHNOL., 2010. © 2010 Society of Plastics Engineers     

Chemically induced graft copolymerization of acrylic acid onto polyester fabrics. I. Kinetic investigation of grafting

The kinetics of grafting of acrylic acid onto poly(ethylene terephthalate) fabrics initiated by benzoyl peroxide has been studied. Extent of grafting depended upon time, concentration of the initiator and the monomer, as well as the presence of the activator used. From the temperature dependence of the initial rate of grafting the overall activation energy for grafting was found to be 90 kJ/mol. The results of the monomer and temperature dependence found in this study are consistent with the rate expression derived from a normal kinetic scheme for grafting.     

凯芙拉纤维/尼龙6热塑性复合材料的研制

研究了凯芙拉纤维与尼龙 6单体通过阴离子原位聚合制备热塑性复合材料的方法。以氢氧化钠为引发剂 ,甲苯二异氰酸酯 (TDI)为活化剂 ,确定体系的聚合温度为 160℃ ,引发剂、活化剂用量为6.42 m ol/L ,聚合时间 60 min,在此条件下聚合速度较快 ,单体转化率 1h后达 95 %以上。研究发现 ,凯芙拉纤维经酰化处理后 ,基本上不会对己内酰胺阴离子聚合体系产生阻聚作用     

GR针刺地毯粘合剂的研制

本文介绍了一种以丙烯酸酯为主体的乳液型针刺地毯粘合剂,讨论了在实际生产过程中,单体配比,加入方式、乳化剂、引发剂、反应温度及搅拌速度对反应体系的影响,并提供了该粘合剂的性能及应用数据。     

l-Ascorbic acid as a new activator in fabrication of ceramics by techniques using in situ polymerization

The paper reports the development of a new system applicable in shaping techniques using in situ polymerization. The system is based on saccharides derivatives and allows to eliminate harmful processing agents from ceramic slurry. Instead of commonly applied 2-hydroxyethyl acrylate or acrylamide (monomers) and N,N,N′,N′-tetramethylethylenediamine (activator) the compounds based on glucose were used. As a monomer 3-O-acryloyl-d-glucose was applied. As a new activator l-ascorbic acid (also known as vitamin C) was used. Research was carried out for YSZ. As initiators ammonium persulfate and hydrogen peroxide were used. The new system was studied in terms of zeta potential, pH and rheological measurements. Ceramic samples were prepared by gelcasting and gel-tape casting methods. The experiments showed that l-ascorbic acid used as the activator has positive influence on rheological properties of suspensions with YSZ and together with ammonium persulfate allows to form defect free ceramic bodies with a homogenous composition.     

A supported titanium postmetallocene catalyst: Effect of selected conditions on ethylene polymerization

Ethylene polymerization with a titanium complex [N,N‐ethylenebis(3‐methoxysalicylideneiminato)titanium dichloride] immobilized on the magnesium support with the formula MgCl₂(THF)_0.32(Et₂AlCl)_0.36 was studied. In particular, the effects of polymerization temperature, monomer pressure, and polymerization time on the activity of the catalyst and on the polyethylene properties (molecular weight and its distribution, melting point, crystallinity, and bulk density) were evaluated. The findings of investigations prove that the studied supported titanium catalyst is highly active in ethylene polymerization, and its activity increases with increasing temperature and monomer pressure. Moreover, stability of the catalytic systems is dependent on the activator type used. Me₃Al, when employed as an activator, makes the catalytic system undergo no deactivation in practice. The catalyst coupled with MAO turned out less stable. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Gelcasting Performance of Alumina Aqueous Suspensions with Glycerol Monoacrylate: A New Low-Toxicity Acrylic Monomer

Gelcasting has been extensively studied and applied as a near-net-shaping technique for preparing complex ceramic parts. However, the use of acrylamide as a main component is an important drawback of this method as it is a hazardous, neurotoxic compound. In this context, a new low-toxicity monomer, glycerol monoacrylate, has been synthesized and successfully used for the gelcasting of ceramic suspensions. The presence of two hydroxyl groups in a monomer molecule allows the formation of a polymer network by the monomer polymerization and cooperative hydrogen bonding without any external crosslinking agent. The stability and rheological behavior of alumina gelcasting suspensions containing the new monomer has been studied by oscillatory measurements under the controlled deformation mode. The results were compared with those obtained for commercially available monomers, 2-hydroxyethyl acrylate and diethylene glycol diacrylate used as a crosslinking agent, in which case the effect of an initiator and activator was studied. The gelcasting performance for both the commercial and the newly synthesized monomers was studied and compared, showing that the former allows a faster gelation, whereas the latter leads to more uniform microstructures and higher sintered densities of up to 99% of TD.     

MC尼龙—碳纤维复合材料的制备

在单体浇铸尼龙的聚合过程中加入１０％各向同性沥青基短切碳纤维，研究了温度及催化剂和活化剂用量对聚合的影响，结果表明：这些参数对聚合物相对分子质量影响很大，而空气湿度对聚合的干扰更为严重；对聚合物的性能测试显示：该尼龙导热系数明显提高，耐压缩性和抗弯曲性得到改善，抗冲击强度有所下降。     

How penultimate monomer unit effects and initiator influence ICAR ATRP of n‐butyl acrylate and methyl methacrylate

The relevance of penultimate monomer unit (PMU) effects and the selection of the correct initiator species under typical reversible deactivation radical copolymerization conditions is illustrated, using matrix‐based kinetic Monte Carlo simulations allowing the visualization of all monomer sequences along individual chains. Initiators for continuous activator regeneration atom transfer radical polymerization (ICAR ATRP) is selected as illustrative polymerization technique with n‐butyl acrylate and methyl methacrylate as comonomers, aiming at the synthesis of well‐defined gradient copolymers. Using literature based model parameters, in particular temperature dependent monomer and radical reactivity ratios, it is demonstrated that PMU effects on propagation and ATRP (de)activation cannot be ignored to identify the most suited ICAR ATRP reactants (e.g., tertiary ATRP initiator) and reaction conditions (e.g., feeding rates under fed‐batch conditions). The formulated insights highlight the need for further research on PMU effects on all reaction steps in radical polymerization. © 2017 American Institute of Chemical Engineers AIChE J, 2017