Synthesis and Polymerization of Novel Cationically Polymerizable Monomers

Abstract

The use of novel chemo- and regioselective hydrosilation reactions to prepare several series of ambifunctional silicon-containing epoxy monomers and oligomers is described. These monomers can be polymerized using traditional cationic initiators or by employing onium salt photoinitiators.     

马来酸类可聚合乳化剂及其在乳液聚合中应用

使用可聚合乳化剂可以很好地解决传统乳化剂的缺点,提高乳液的应用性能.马来酸类乳化剂其可聚合基团反应活性适中,可以很好地键合在乳胶粒表面上,且更为突出的是这类乳化剂不易发生均聚,而是倾向于与单体发生共聚.研究表明,马来酸类可聚合乳化剂应用到乳液聚合中,可以改善乳胶液的性能,提高乳胶膜的耐水性等.文章介绍了这一类新型的乳化剂,并根据其亲水基团进行了分类,分别介绍其合成路线,总结了马来酸类乳化剂的特点,概述了在常见乳液聚合体系中的应用与研究.     

非离子型可聚合聚氨酯/苯乙烯的超浓乳液聚合

研究了以非离子型可聚合聚氨酯(PUAG)和苯乙烯(St)为混合单体的超浓乳液聚合, 并且考察了n(NCO)/n(OH)摩尔比、复合乳化剂体系质量浓度[E]、不同乳化剂的种类、引发剂质量浓度[I]、单体体积分数(或分散相体积分数, 也称内相比Φ)、聚合温度等因素对聚合稳定性、动力学的影响. 同时结合光相关光谱(PCS)测定了聚合物乳胶粒子大小和粒径分布, 用透射电子显微镜(TEM)观察了粒子形态, 结果表明: 当n(NCO)/n(OH)＝2∶1, T＝328 K, Φ＝80.39%, [I]＝0.8% g/g (PUAG-St), [E]＝0.22 g/mL H₂O, m(MS-1)/m(CA)＝2∶1, PVA＝0.01 g/mL H₂O时, 超浓乳液不仅有较好的聚合稳定性和较快的聚合速率, 而且粒径小分布均匀. 同时, 在此条件下的表观动力学表达式和表观活化能分别确定为R_p＝k[I]^0.50[E]^0.73[M]^0.54和 E_a＝29.7 kJ/mol. 热失重分析(TGA)进一步表明: 调节PUAG的含量可以达到对聚苯乙烯的改性, 提高聚苯乙烯的热稳定性.     

等离子体聚合法

扼要介绍等离子体聚合的原理、设备和方法,对其应用也作了叙述。     

马来酸类可聚合乳化剂的合成及其在细乳液聚合中的应用

采用三步法合成了可聚合乳化剂马来酸单十六醇酯丙基磺酸钠.并用正交实验法优化了马来酸单十六醇酯合成工艺条件,结果表明反应的最佳条件为:催化剂质量分数1%,反应时间3.0h,反应温度90℃,马来酸酐与十六醇的摩尔比1.1:1.苯乙烯-丙烯酸丁酯细乳液聚合使用该乳化剂与传统乳化剂相比,在较低温度下(65℃)具有较高的转化率,且所得乳液具有较好的电解质稳定性,乳胶膜的耐水性也得到提高.     

六甲基二硅胺烷的等离子体聚合

在室温和无添加气体条件下,完成了六甲基二硅胺烷较低功率密度的等寒子体聚合。研究了聚合膜的沉积规律和过程。给出了聚合物膜的结构和性质。得到经验式为 C_(1.42)H_(2.65)N_(0.2)O_(0.15)Si的新聚合物。     

Fundamentals of Plasma Polymerization

The plasma polymerization of ethylene is used as an example through which to discuss the elementary steps involved in forming a polymer in an electric discharge. The relationship of the experimentally controlled variables to the rate of formation of first generation active species is discussed. These species are related, in turn, to the overall rate of polymerization through a simple model. Two asymptotic conditions are discussed which correspond to minimal and total conversion of monomer to polymer. The dependence of polymer deposition rate on monomer flow rate predicted by the model is found to correspond very closely to that observed experimentally. The predicted effect of gas pressure on polymer deposition rate also agrees with that found experimentally.     

Plasma Polymerization on Metals

An ellipsometric technique is described for accurately measuring the film thickness of plasma-polymerized polymers on metallic substrates. The index of refraction n and absorption index Kof the plasma polymer film can also be studied by ellipsometry. Films of plasma polystyrene and polyepichlorohydrin were deposited on evaporated aluminum substrates and their thickness and optical constants determined. Plasma polystyrene films from 20 to 1600 Å thick have optical constants n = 1.63 and K =0 independent of film thickness. Plasma polyepichlorohydrin films over the same range of thickness give n ? 1.70 and K? 0.01. By utilizing the ellipsometric method the effect of plasma polymer film thickness on surface energy properties was determined. Advancing contact angle measurements and surface energy analysis detail the polar γSV^P dispersion γSV^Pcontributions to the solid-vapor surface tension γSV = γSV^d + γSV^P Polystyrene and polyepichlorohydrin films on etched aluminum. For thin plasma polystyrene films (600 Å), anomalies in the calculated surface energy are discussed and related to possible surface nonuniformity caused by film growth. Thicker films of plasma polystyrene are shown to have normal surface energy properties as does plasma poly-epichlorohydrin over the entire range of film thickness measured. The adhesive and cohesive properties of plasma polystyrene and polyepichlorohydrin films are discussed as estimated from a lap-shear bond strength study. Etched aluminum coated with various thicknesses of these two polymers and bonded with an epoxy-phenolic adhesive shows a decreasing shear strength with increasing plasma film thickness but begins to level off at ～1600 psi for films >1600 Å thick.     

Templating Polymerization of Dodecylammonium Surfactants with Polymerizable (Meth)acrylate Counter Ions

Both dodecylammonium acrylate (I) and dodecylammonium methacrylate (II) are reactive surfactants in which the polymerizable group is the organic counterion. Templating polymerization of I and II from the lyotropic liquid crystalline (LLC) lamellar phase was successfully performed with conservation of the supramolecular structure. A 20 wt% aqueous solution of II formed cubic bicontinuous phases, even upon addition of divinyl benzene (DVB). Polymerization from the cubic phases was attempted without and with DVB (3 wt%). Bicontinuous cubic phases always evolved toward lamellar structures upon polymerization.     

等离子体聚合及其聚合物的应用

本文着重综述了烃,含氮、氧的有机化合物,碳氟化合物以及有机硅化合物的等离子体聚合。同时还系统地介绍了等离子体聚合物在制备反渗透膜、分离膜、材料表面的涂层等方面的国内外的最新研究成果。     

GC—MS方法测定等离子体引发丙烯酸酯聚合引发活性种

在等离子体引发的液态丙烯酸酯类单体聚合体系中加入大量链转移剂乙硫醇,得到了端基带有引发活性种的低聚物,利用气相色谱-质谱的多离子检测手段,测定了活性种的结构,结果表明:引发活性种是单体在等离子体区裂解生成的酯基碎片[-C—O—R].进而解释了丙烯酸酯类单体可以由等离子体引发聚合,而苯乙烯不能引发聚合的问题.     

碳氟化合物等离子体聚合研究进展

本文综述了近年来碳氟等离子体聚合物研究的新进展,主要包括3个方面:(1)碳氟化合物的等离子体聚合反应历程;(2)碳氟等离子体聚合物的结构表征,着重介绍了电子能谱在表征其结构中的应用;(3)碳氟等离子体聚合物的应用领域。     

N-丙烯酰吗啉在可聚合叔胺-过硫酸钾水溶性引发体系引发下的水溶液聚合

本文报道了以甲基丙烯酸－N，N－甲氨基乙酯（DMAEMA）与过硫酸盐体系以引发的丙烯酰吗啉（AMP）的水溶液聚合，得到下列方程：Rp［K2S2O8］0．46［DMAEMA］0．49［AMP］1．09；Ea＝30．21KJ／mol。试用四氯乙烯（TCNE）处理的丙烯酸吗啉聚合物P（AMP）的紫外光谱分析，发现DMAEMA不仅参与引发AMP聚合，而且还进入P（AMP）分子链中。P（AMP）分子量比聚丙烯酰腹P（AAm）的小，而且随AMP（DMAEMA或温度）增加而增加（降低）。P（AMP）及其轻度交联的水凝胶表现出热敏性。     

Free Radicals Resulting from Plasma Polymerization and Plasma Treatment

A glass tube is subjected to plasma treatment (non-polymerizable plasma) or plasma coating (polymerizable plasma). Unpaired spins generated in the glass substrate alone, and in both substrate and coating for the second case, are detected by ESR It is shown that for both polymerizable and nonpolymerizable plasmas the substrate's unpaired spins (glass radicals) are caused, in large part, by UV radiation from the plasma. In the case of plasma coating, the glass radicals are formed at the outset of the polymerization because the coating increasingly absorbs the UV radiation as deposition continues. High concentrations of free radicals in the coating appear to be correlated with a high tendency to polymerize, while high values of substrate radical surface concentration are related to high levels of UV intensity in the plasma.     

吡咯等离子体聚合产物分析

用色谱－质谱、裂解色谱－质谱、电子自旋共振、红外光谱及元素分析等方法鉴定了吡咯等离子体聚合过程中气相冷凝物和聚合物的组成，根据分析结果提出了吡咯等离子体聚合的自由基反应历程。     

可聚合表面活性剂的研究进展

在乳液聚合中，表面活性剂发挥着非常关键的作用，但同时它们也存在不足的方面，一个比较有前景的方法就是使用可聚合表面活性剂。可聚合表面活性剂以牢固的共价键键合到聚合物粒子上，有效避免了表面活性剂的解析及其在膜中的迁移。本文综述了近年来可聚合表面活性剂的进展，主要讨论了阴离子、非离子、阳离子可聚合表面活性剂的特征和性质及其在乳液聚合中的应用。     

等离子体引发丙烯酰胺的反相悬浮聚合

通过等离子体引发技术进行了丙烯酰胺的反相悬浮聚合研究,考察了后聚合时间,放电时间,放电功率,单体浓度,分散剂浓度及溶剂极性对聚合物分子量和转化率的影响。结果发现：延长后聚合时间有利于反应的进行,而在聚合反应中存在着一个最佳的单体浓度值,增加溶剂的极性有利于反应进行,降低体系中空气残留量也有利于反应进行。     

The Role of Halogens in the Plasma Polymerization of Hydrocarbons

Vinyl chloride, vinyl fluoride, and tetrafluoroethylene were polymerized in a radio frequency electric glow discharge. It was found that when compared with the unhalogenated simple hydrocarbons, the rates of polymer deposition are in the order vinyl chloride, acetylene, tetrafluoroethylene, vinyl fluoride, ethylene. This observation can be rationalized by considering the ease with which free radical and unsaturated species can be formed in the plasma. IR spectra show that the structures of plasma-polymerized vinyl chloride and vinyl fluoride are in many respects similar to the plasma-polymerized hydrocarbon. The spectrum of plasma-polymerized tetrafluoroethylene, however, does not resemble that of conventional polytetrafluoroethylene. Addition of dichlorodifluoromethane to the monomer stream dramatically increased the polymer deposition rate; the effect is more subdued for chloromethane and is negligible for tetrafluoromethane. Elemental analysis indicates that little of the added halogens is present in the resultant polymers. Thus the halogenated compounds appear to act as a gas phase catalyst for the plasma polymerization of hydrocarbons.     

间接等离子体聚合制备聚吡咯薄膜

通过吡咯在氩辉光放电气流下游区域的间接等离子体聚合作用制备了聚吡咯薄膜。研究了聚合膜的沉积速率，用ＦＴＩＲ、ＸＰＳ、ＳＥＭ、ＸＲＤ、ＴＥＤ等手段表征了聚合膜的结构和形态。结果表明，聚合膜完整地保留了吡咯单体的共轭结构，显示出较高的导电性，化学掺杂碘以后膜的室温电导率为１０－７～１０－６Ｓ／ｃｍ。     

二甲基甲酰胺在聚乙烯膜表面的等离子体聚合

通过二甲基甲酰胺的等离子体聚合作用，对聚乙烯膜进行表面改性。研究了等离子体工艺参数对聚合物膜沉积速度的影响，用ＦＴＩＲ、ＸＰＳ分析了聚合物膜的组成结构，测定了改性聚乙烯膜的接触角和表面。