有机硅—丙烯酸酯乳液共聚合

以硅氧烷，丙烯酸乙酯为原料，经乳液聚合制备了有机硅－丙烯酸酯共聚物。实验证明，在以丙烯酸乙酯为主的体系中，加入不大于３０％（质量）的硅氧烷进行乳液共聚合，不影响聚合反应的正常进行，当乳化剂液度（［Ｅ］）为（２．０１－１０．０９）×１０＾－２ｍｏｌ／Ｌ，引发剂浓度（［Ｉ］）为（０．８６－５．２６）×１０＾－３ｍｏｌ／Ｌ时，本体系聚合动力学关系式为Ｒ∝［Ｅ］＾０．６［Ｉ］＾０．５；共聚胶乳粒子的粒径及     

立构嵌段聚丁二烯的研制 Ⅴ．立构三嵌段聚丁二烯的合成及动力学行为

以α－甲基萘锂（α－ＭＮＬｉ）为引发剂、二哌啶乙烷（ＤＰＥ）为调节剂、环己烷为溶剂的丁二烯负离子聚合体系，研究了ＤＰＥ／α－ＭＮｌｉ、聚合温度与聚合物１，２－结构含量关系，合成出１，２一结构近１００％的１，２－聚丁二烯（１，２－ＰＢ）和１，２－１，４－１，２－ＰＢ。反应动力学研究表明：１，４－ＰＢ与１，２－ＰＢ中单体浓度与反应速率呈一级方程关系；４０℃时，生成１，４－ＰＢ的反应动力学方程式为－ｄ［Ｍ］／ｄｔ＝０．２８［Ｃ］￣０．５［Ｍ］；ＤＰＥ用量增大，表观增长反应过度常数Ｋ＿ｐ￣η减小；求得不同条件下的表观增长活化能。     

负载钛催化异戊二烯本体沉淀聚合动力学的研究

采用负载钛催化剂,在０￣３０℃下对异戊二烯（Ｉｐ）本体沉淀聚合的动力学进行了研究。结果表明,体系在单体相未消失之前为稳态聚合,其稳态聚合速率方程为：Ｒｐ＝ｋｐｆ［Ｔｉ］０［Ａｌ］０［Ｍ］０,即在单体相未消失前,Ｒｐ为恒量。计算出Ｉｐ本体沉淀聚合的表观活化能为２９．７ｋＪ／ｍｏｌ,催化剂利用率为２０％￣３０％,高于溶液聚合法。     

有机硅－丙烯酸酯乳液共聚合

以硅氧烷、丙烯酸乙酯为原料，经乳液聚合制备了有机硅－丙烯酸酯共聚物。实验证明，在以丙烯酸乙酯为主的体系中，加入不大于３０％（质量）的硅氧烷进行乳液共聚合，不影响聚合反应的正常进行；当乳化剂浓度（［Ｅ］）为（２．０１～１０．０９）×１０￣（－２）ｍｏｌ／Ｌ，引发剂浓度（［Ｉ］）为（０．８６～５．２６）×１０￣（－３）ｍｏｌ／Ｌ时，本体系聚合动力学关系式为Ｒ∝_（ｘ）［Ｅ］￣（０．６）［Ｉ］￣（０．５）；共聚胶乳粒子的粒径及其分布，极大地受到聚硅氧烷助乳化作用的影响，其平均粒径为０．０４８４μｍ，明显小于聚丙烯酸酯的粒径。     

可见光敏引发聚合甲基丙烯酸甲酯的动力学研究

本论文用膨胀计法进行了甲基丙烯酸甲酯在氯仿溶液中可见光光敏引发聚合动力学的研究．此光敏引发体系由光敏剂１,３,３－三甲基－２－［５－（１,３,３－三甲基－２－吲哚叉）－１,３－戊二烯］吲哚碘盐（简称ＮＫ－５２９）,引发剂邻氯代六芳基双咪唑（简称ｏ－Ｃｌ－ＨＡＢＩ）,氢给体３－巯基－４－甲基－４氢－１,２,４－三氮唑（简称ＭＴＡ）组成．研究结果表明,此光敏聚合体系的光聚合速率与各组分的动力学方程如下：Ｒｐ＝Ｋ（ＮＫ－５２９）０．５１（ＨＡＢＩ）０．４１（ＭＴＡ）０．３６（ＭＭＡ）１．０     

碳笼烯钕系催化异戊二烯聚合的动力学行为

测定了Ｎｄ（ｎａｐｈ）３－碳笼烯衍生物（Ｃ６０Ｘｎ）－Ａｌ（ｉ－Ｂｕ）３催化体系引发异戊二烯溶液聚合的动力学行为。在低转化率条件下,体系呈现稳态聚合特征,测量聚合反应速率方程为Ｒｐ＝Ｋｐ［Ｎｄ］＾１．８［Ｍ］０,表观活化能为２７．７ｋＪ／ｍｏｌ。体系具有聚合活性的高温稳定性和准活性聚合的特征。     

稀土络合催化剂引发丁二烯的聚合动力学

研究了Ｎｄ（ｎａｐｈ）３－Ａｌ（ｉ－Ｂｕ）２Ｈ－Ａｌ（ｉ－Ｂｕ）２Ｃｌ催化体系引发丁二烯聚合动力学，得到了聚合速度方程式－ｄ［Ｍ］／ｄｔ＝ｋｐα［ｃ］０［Ｍ］。发现聚合物的Ｍｎ在聚合过程中随着单体转化率的增加而下降。测得了该催化体系的活性中心浓度和有关动力学参数。     

煤油/Span80-Twen60/水/丙烯酰胺反相微乳液聚合动力学

以煤油为油相,以Ｓｐａｎ８０与Ｔｗｅｎ６０为复合乳化剂,对ＡＩＢＮ引发丙烯酰胺反相微乳液聚合宏观动力学进行了研究,得到Ｒｐ∝［Ｍ］１．５０［Ｉ］０．６９［Ｅ］１．５６,聚合表观活化能为６８．８ＫＪ／ｍｏｌ,并且发现聚合过程中出现短暂的恒速期。同时对ＫＰＳ引发聚合体系亦进行了比较考察。最后对乳胶粒作了初步讨论,发现每个粒子内所含的大分子链数量很少。     

苯乙烯- 丙烯酸丁酯- 丙烯酸羟乙酯共聚物的合成及其与二异氰酸酯的交联

当混合溶剂乙酸丁酯／二甲苯质量比为１∶１,过氧化苯甲酰（ＢＰＯ）为１％,苯乙烯（Ｓｔ）／丙烯酸丁酯（ＢＡ）＋丙烯酸羟乙酯（ＨＥＡ）（质量比）为６２∶３８,反应温度为１３３℃时,可获得转化率为９５．３％、［η］为０．１６ｄＬ／ｇ的Ｓｔ－ＢＡ－ＨＥＡ共聚物。该共聚物（ＨＥＡ的结合量为２％～４％）在同一溶剂中加入甲苯二异氰酸酯（ＴＤＩ）或聚醚型二异氰酸酯（ＰＥＤＩ）,当—ＮＣＯ／—ＯＨ摩尔比为１．２～１．５∶１,二丁基二月桂酸锡用量为０．３％～１．０％时,可于室温下交联,交联度为５８．３％～５９．１％     

n-BuLi 的浓度对异戊二烯聚合的影响(英)

研究了不同ｎ － ＢｕＬｉ 浓度时的异戊二烯假一级增长反应速率常数Ｋｐ′′, 发现当［ｎ － ＢｕＬｉ］ 低于７×１０－４ ｍｏｌ／Ｌ 时, Ｋｐ′′随［ ｎ － ＢｕＬｉ］ 的增大而增大;［ｎ －ＢｕＬｉ］ 高于７×１０－４ ｍｏｌ／Ｌ 时,Ｋｐ′′随［ ｎ － ＢｕＬｉ］ 的增加而有所下降。［ ｎ － ＢｕＬｉ］ 不大于７×１０－ ４ ｍｏｌ／Ｌ 时的动力学方程为Ｒｐ ＝ ０．３７［ｎ － ＢｕＬｉ］０ ．２６６［ Ｍ］ 。     

Radical/Addition polymerization silicone hydrogels with simultaneous interpenetrating hydrophilic/hydrophobic networks

Transparent silicone hydrogels with interpenetrating hydrophilic/hydrophobic networks were simultaneously synthesized on the basis of the radical polymerization of the methacrylic monomer of 3‐methacryloxypropyl tris(trimethylsiloxy) silane (TRIS)/N,N‐dimethylacrylamide (DMA) and the addition polymerization of hydroxyl‐grafted polysiloxane (HPSO)/isophorone diisocyanate. The curing temperature was set at 80°C by a differential scanning calorimetry study. The polymerization process was studied by in situ Fourier transform infrared spectroscopy. The results indicate that the curing time was about 4.5 min, and the addition polymerization had a faster rate than radical polymerization. Then, the radical polymerization rate increased rapidly, and this led to instant curing. The interpenetrating polymer network (IPN) silicone hydrogels were characterized by swelling kinetics and dynamic mechanical thermal analysis. The results show that all of the hydrogels reached swelling equilibrium at about 4 h in water, and the IPN silicone hydrogels with a hydrophobic network of HPSO indicated a slower water transport than that of the copolymerization hydrogel of DMA and TRIS. The hydrophobic network was finely dispersed in the hydrophilic network, and the increasing hydrophobic network of HPSO decreased the glass‐transition temperature of the IPN silicone hydrogels. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41399.     

Reverse ATRP of acrylonitrile with diethyl 2,3-dicyano-2,3-diphenyl succinate/FeCl3/iminodiacetic acid

The reverse atom transfer radical polymerization (RATRP) technique using FeCl₃/iminodiacetic acid (IMA) complex as a catalyst was applied to the living radical polymerization of acrylonitrile (AN). A hexa-substituted ethane thermal initiator, diethyl 2,3-dicyano-2,3-diphenylsuccinate (DCDPS), was firstly used as the initiator in this iron-based RATRP system. The polymerization in N,N-dimethylformamide not only shows the best control of molecular weight and its distribution but also provides rather rapid reaction rate with the ratio of [AN]:[DCDPS]:[FeCl₃]:[IMA] at 500:1:2:4. The rate of polymerization increases with increasing the polymerization temperature and the apparent activation energy was calculated to be 49.9 kJ mol⁻¹. The polymers obtained were end-functionalized by chlorine atom, and they were used as macroinitiators to proceed the chain extension polymerization in the presence of FeCl₂/IMA catalyst system via a conventional ATRP process. The resultant polyacrylonitrile fibers were obtained with the fineness at 1.16 dtex and the tenacity at 6.01cN dtex⁻¹.     

Inline monitoring of styrene/butyl acrylate miniemulsion polymerization with attenuated total reflectance/Fourier transform infrared spectroscopy

The copolymerization of styrene/butyl acrylate in a miniemulsion was monitored inline with an attenuated total reflectance/Fourier transform infrared (ATR–FTIR) probe. ATR–FTIR spectroscopy was used to track the concentration of the monomers, thereby providing conversion and polymer composition data. Offline gravimetry and ¹H‐NMR spectroscopy were used to provide a comparison with the ATR–FTIR data. Because of inconsistent results with a univariate method, a multivariate or partial least squares calibration method using the full spectra of the reactions was selected and gave excellent results. No statistically significant differences were found between the offline and ATR–FTIR spectroscopy data coupled with multivariate statistics, and this confirmed that ATR–FTIR spectroscopy is a reliable tool for monitoring the conversion and polymer composition in miniemulsion polymerizations. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 46–52, 2007     

Poly(tert-butyl acrylate-b-isobutylene-b-styrene) terpolymer from a carbocationic initiator containing a latent radical initiating site

A poly(isobutylene-b-styrene) (PIB-PS) copolymer was synthesized via quasi-living carbocationic polymerization from an initiator containing a latent site for atom transfer radical polymerization (ATRP) initiation. The initiator, 3,3,5-trimethyl-5-chlorohexyl acetate (TMCHA), was synthesized in four steps from methyl 3,3-dimethyl-4-pentenoate. The PIB block was created at −70 °C in a methylcyclohexane/methyl chloride (60:40) cosolvent system, using TiCl₄ as the catalyst, followed by sequential addition of styrene. The acetate head group of the resulting block copolymer was converted to a hydroxyl group using a strong base and subsequently esterified with 2-bromopropionyl bromide to create an initiating site for ATRP of tert-butyl acrylate, which was carried out using a Cu(I)Br/1,1,4,7,7,-pentamethyl-diethylenetriamine (PMDETA) catalyst system. The final terpolymers had compositions that were very close to theoretical.     

1,4-二氧六环在IBVE/Cl_2/TiCl_4聚合体系中的作用机理

<正> 1 引言 控制高分子结构、合成和制备嵌段、序列共聚物是目前聚合物合成的重要课题.在各种方法中,活性聚合是简单、经济和较通用的方法.作者曾在低于-70℃的Cl_2/TiCl_4/IBVE(异丁基乙烯基醚)/CH_2Cl_2体系中实现了活性阳离子聚合,温度高于-70℃或用其它溶剂则不能得到活性聚合物.本实验目的是研究在IBVE/Cl_2/TiCl_4体系中加入给电子添加剂DOX(1,4-二氧六环),通过DOX与增长活性链之间的相互作用,使碳阳离子稳定,探索在较高温度下或其它溶剂中的活性聚合的可能性。     

铬/钒双金属催化剂催化乙烯气相聚合

在实验室小试气相聚合釜中对铬/钒双金属催化剂进行乙烯聚合评价,考察了不同聚合温度和压力时催化剂的性能,研究了不同条件下催化剂的动力学行为,并将其聚合动力学曲线与用工业铬系催化剂的进行了比较。结果表明:随着聚合温度升高,用铬/钒双金属催化剂制备的聚乙烯的相对分子质量减小,熔体流动速率增大,在所研究聚合温度范围内铬/钒双金属催化剂对温度更敏感;随着聚合压力增大,催化剂活性显著提高,聚乙烯相对分子质量增加;聚合动力学曲线与铬系催化剂不同,聚合反应速率先增大再降低最后逐渐达到平稳。     

Macromolecular architectures by living and controlled/living polymerizations

The discovery of living anionic polymerization by Szwarc 50 years ago opened the way to the synthesis of model polymers. This ground-breaking discovery inspired many researchers to develop controlled/living routes for a plethora of monomers including those not compatible with anionic polymerization. These methods and their combinations serve as an arsenal for the synthesis of well-defined polymeric materials with predetermined properties and a rich variety of applications. A few representative examples of living and controlled/living methodologies for the synthesis of polymers with different macromolecular architectures are presented in this review.     

种子聚合法制备PS/PAA核壳微球的研究

设计制备了以疏水性聚苯乙烯(PS)为核、以亲水性聚丙烯酸(PAA)为壳的PS/PAA核壳结构复合微球。首先利用无皂乳液聚合法制备了亚微米级的PS微球,再以其为种子,利用种子无皂乳液聚合法制备PS/PAA核壳微球。在种子聚合阶段,选用AIBN当引发剂,经过红外光谱(IR)表征,表明当使用油溶性引发剂偶氮二异丁腈(AIBN),使其最终形成PS/PAA核壳结构微球。这种方法解决了亲水性较强的单体在以水为介质时在PS微球溶于少量的苯乙烯(St),并在引发聚合之前经过充分的吸附溶胀,可使亲水性单体AAc在PS种子微球表面聚合生成壳层,解决表面不容易直接聚合生成壳层的问题。     

Particle formation mechanism in radical polymerization in miniemulsion based on in situ surfactant formation without high energy homogenization

Conventional radical polymerization of styrene at 70 °C in aqueous miniemulsion generated using the in situ surfactant technique, without use of high energy mixing, has been investigated in detail. The surfactant potassium oleate was formed in situ by reaction between oleic acid and potassium hydroxide at the styrene/water interface. The particle formation mechanism was investigated by use of pyrene as a probe, revealing that under suitable conditions with an oil-phase initiator, particle formation occurs primarily via monomer droplet nucleation. The droplet/particle stability is however inferior to that in a typical miniemulsion generated employing ultrasonication, as manifested by a marked increase in droplet/particle size with conversion and a bimodal droplet/particle size distribution by weight. The droplet/particle stability increases with increasing amount of oleic acid, hexadecane, water, and the ratio potassium hydroxide:oleic acid, respectively.     

Preparation and properties of alkoxysilane/butyl acrylate/methyl methacrylate copolymer latices

The incorporation of alkoxysilanes into latex systems is of major interest in the field of colloidal science. Two kinds of vinyl‐containing alkoxysilanes, methacyloxypropyltrimethoxyl silane and vinyltriethoxysilane, were copolymerized with butyl acrylate and methyl methacrylate by seeded emulsion polymerization, and copolymer latices were obtained. The morphologies of the latex particles were characterized with transmission electron microscopy. Dynamic light scattering showed that the particle size increased and the particle size distributions of all the copolymer latex particles were alike with increasing amounts of organosilane. The effects of the organosilane content on the morphology of the particles, the rheology, and the swelling properties were also investigated. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009