自交联型改性苯丙乳液的制备及其用于防水涂料的性能研究

以丙烯酸（AA）、丙烯酸丁酯（ BA）和苯乙烯（St）为基础单体,通过调控功能单体甲基丙烯酸缩水甘油酯（ GMA）的用量制备了一种自交联型改性苯丙乳液（ PGSA）对乳液粒径大小与分布、形态与形貌以及乳液涂膜吸水性能进行了表征。以 PGSA乳液为液料辅以无,机水泥等填料制备了双组分聚合物水泥防水涂料,对其抗渗及力学性能进行了研究。结果表明：当 GMA用量为 7%时（以单体 AA、BA和 St的总质量计）,PGSA乳液的粒径为 210 nm、粒径分布（PDI）为 0. 17~0. 21,且放置 6个月后乳液的粒径及分布基本保持不变。此外,随着 GMA用量的增加, PGSA乳液涂膜的吸水率呈下降趋势。 PGSA基防水涂料的抗渗性、抗拉强度及断裂伸长率都符合 GB/T 23445—2009《聚合物水泥防水涂料》标准的要求,应用前景广阔。     

新型环保复合乳化剂对苯丙乳液性能影响

采用间歇式预乳化聚合工艺,选用环保型阴非离子型乳化剂异构十三醇聚氧乙烯醚硫酸铵（DNS-525）和非离子乳化剂烷基醇聚氧乙烯醚（EFS-470）替代传统的烷基酚聚氧乙烯醚（APEO）乳化剂,并与交联单体复配成助剂1和助剂2。采用多因素正交小试实验考察三个因素（助剂1、保护胶体PVA1788、助剂2）对JS防水涂料用的苯丙乳液性能的影响,用FTIR对其结构进行表征。试验表明：新型复配乳化剂能大大提高乳液的稳定性,减少乳化剂的用量;助剂1对胶乳性能影响最大,助剂2次之,保护胶体PVA1788最小,并得到最佳的工艺参数;以此优化工艺参数为依据,制备出稳定性和涂膜弹性优异的苯丙乳液,该乳液和水泥粉料以1.4：1混合,制备出涂膜拉伸强度为2．1MPa,断裂伸长率为200％的高性能JS防水涂料。     

Role of acrylic acid in the synthesis of core‐shell fluorine‐containing polyacrylate latex with spherical and plum blossom‐like morphology

The core‐shell fluorine‐containing polyacrylate latex was successfully synthesized by two‐stage semicontinuous emulsion copolymerization of methyl methacrylate (MMA), butylacrylate (BA), acrylic acid (AA), and dodecafluoroheptyl methacrylate (DFMA). The fluorine‐containing polyacrylate latex was characterized by Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), dynamic light scattering (DLS), zeta potential, thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC). The effects of AA content on monomer conversion, polymerization stability, particle size, corsslinking degree, carboxyl groups distributions (latex surface, aqueous phase or buried in latex), as well as mechanical properties and water absorption rate of latex film were investigated. The obtained fluorine‐containing polyacrylate latex exhibited core‐shell structure with a particle size of 120–150 nm. The introduction of AA was beneficial for the increase of monomer conversion and the polymerization stability, and had little effects on the mechanical property of latex film. However, the hydrophilicity of AA made the water resistance of latex film get bad. With the increase of AA content, the carboxyl groups preferred to distribute on aqueous phase, and the possibility of homogeneous nucleation increased and more oligomers particles were formed. Moreover, the oligomers would distribute to the latex and continued to grow up, making the latex morphology changed from spherical to plum blossom‐like. The core‐shell latex had two T_g corresponding to the rubber polyacrylate core and hard fluorine‐containing polyacrylate shell, and the latex film possessed excellent thermal stability. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42527.     

浅析聚合物水泥防水砂浆的研制

通过对比试验,选择出了聚合物水泥防水砂浆的原料品种和适宜的质量配比;在此基础上,配制出具有超强粘结性能及抗渗能力优异的刚性抗渗防水材料,并介绍了这种聚合物水泥防水砂浆的施工方法。试验结果表明,不同聚灰比对防水砂浆压折比有明显影响;超细矿物粉与可分散胶粉的协同作用能提高砂浆的抗渗性、耐久性及粘结性能;级配砂与纤维能改善防水砂浆的抗裂性及收缩率。     

The effect of the polymerization route on the amount of interphase in structured latex particles and their corresponding films

Three series of hard/soft styrene-acrylic latex based systems with equivalent compositions were prepared either by blending of homopolymer latexes or by preparing structured latex particles having core shell (CS) or inverted core shell (ICS) morphologies. Transmission electron microscopy (TEM) was used to investigate the particle morphologies, which were correlated to the calculated fractional radical penetration for the propagating species during the reactions. The thermo-mechanical properties as well as the morphology of the resulting latex films were analyzed by differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA) and TEM. The viscoelastic properties of the interphase between the first and second-stage polymers formed in the structured hard/soft latex films, as well as its qualitative amount and also the film morphologies were found to depend on the interplay between thermodynamic and kinetic parameters during the synthesis of the samples.     

乙酰乙酸基甲基丙烯酸乙酯/乙二胺体系对室温自交联苯丙乳液性能的影响

为克服线型结构苯丙乳液聚合物的缺点,采用半连续种子预乳化工艺在乳液聚合中引入乙酰乙酸基甲基丙烯酸乙酯(AAEM),以乙二胺(EDA)为交联剂,获得室温自交联苯丙乳液。研究了AAEM/EDA体系对苯丙乳液聚合物性能的影响,以及在水性涂料中的应用。结果表明,该体系能够在苯丙乳液成膜时发生室温自交联,提高聚合物的耐水性、耐溶剂性、热稳定性与物理机械性能,并改善苯丙乳液涂料漆膜的光泽、耐洗刷性、附着力、耐盐水性与耐盐雾性。     

Effect of Iron Coating on Thermal Properties of Aluminum‐Lithium Alloy Powder

Aluminum‐lithium alloys are widely studied to improve performance in energetic materials. However, their high reactivity causes severe surface oxidation over micro‐Al particles in storage, resulting in significant deterioration in the overall performance. This study deals with the effect of iron coating on thermal properties and aging stability of aluminum‐lithium alloy powder. Gas atomized Al‐3Li (3 wt. %) alloy powder was prepared and then successfully coated with nano‐sized iron film by modified chemical liquid deposition method. The morphology, thermal properties and combustion enthalpies were characterized by SEM/EDX, TG/DTA and oxygen bomb calorimeter. The results showed that Fe/Al‐3Li composite powder presented obvious core‐shell structure and the outer iron film was very uniform and compact. Significantly enhanced thermal reactivities of Al‐3Li alloy powder and Fe/Al‐3Li composite powder were achieved compared with pure Al. In addition, aging studies indicated that, after coating, the reactivity decay rates of alloy powder decreased significantly, and the mass combustion enthalpies remained basically stable, which demonstrated that iron coating indeed prevented pre‐oxidation of the alloy powder and improved its aging stability.     

硅烷偶联剂对复合水泥砂浆性能的影响

通过红外光谱分析及砂浆强度测试，研究了硅烷偶联剂对不同种类复合水泥砂浆的稠度、分层度、抗折强度及抗压强度的影响。结果表明，加入硅烷偶联剂能提高普通水泥砂浆、苯丙胶乳改性水泥砂浆的抗折强度和抗压强度；当硅烷偶联剂质量分数为0．5％时，普通水泥砂浆的抗折强度和抗压强度达到极大值，提高约10％；当硅烷偶联剂质量分数为1％时，苯丙胶乳改性水泥砂浆的抗折强度和抗压强度达到极大值，提高约20％；同时，硅烷偶联剂还能增大普通水泥砂浆和苯丙胶乳改性水泥砂浆的稠度，但砂浆的分层度略有增大。加入经硅烷偶联剂处理的钢纤维，能够提高普通水泥砂浆及苯丙胶乳改性水泥砂浆的抗折强度和抗压强度；当钢纤维用硅烷偶联剂质量分数为1％的硅烷偶联剂水溶液处理时，钢纤维增强砂浆的抗折、抗压强度达到极大值，提高10％以上。     

Synthesis and properties of fluorine–silicon modified polyacrylate hybrid latex particles with core–shell structure obtained via emulsifier‐free emulsion polymerization

A core–shell fluorine–silicon modified polyacrylate hybrid latex was successfully prepared via emulsifier‐free emulsion polymerization. The chemical composition and core–shell morphology of the resultant hybrid particles were investigated using ¹H NMR and Fourier transform infrared spectroscopies and transmission electron microscopy (TEM), respectively. TEM analysis indicated that the core–shell hybrid particles were uniform with narrow size distributions. The particle size and zeta potential decreased with an increase of alkylvinylsulfonate surfactant from 2.5 to 6.0 wt%. X‐ray photoelectron spectroscopy revealed that fluorine concentrated preferentially at the film surface during a film‐formation process. The film formed from the fluorine–silicon modified polyacrylate showed much higher thermal stability than a film formed from polyacrylate and fluorine‐modified polyacrylate. Contact angle results showed that a finished fabric had remarkable water repellency. © 2015 Society of Chemical Industry     

细乳液聚合法制备PY-17/PE蜡/PS复合乳胶粒子

通过细乳液聚合法制备彩色墨粉用多组分复合乳胶粒子,即通过细乳液聚合法制备聚苯乙烯包覆有机颜料PY-17和聚乙烯蜡的三元复合乳胶粒子。通过透射电子显微镜、激光粒度仪、紫外可见分光光度计和热失重分析仪对制备的复合乳胶粒子形貌、粒度、热学和光学特性进行表征,着重研究了乳化剂种类及用量、颜料用量和聚乙烯蜡用量对复合乳胶粒子粒径和形貌的影响,并对复合乳胶粒子的热学及光学特性进行了表征。结果表明,使用复合乳化剂,颜料PY-17用量不大于单体量8%、聚乙烯蜡用量占单体量不大于10%时,制备的复合乳胶粒子粒径较小,分布窄,包覆较为完整;并且复合乳胶粒子的热学及光学特性发生了一定的改变。     

用于可再分散乳胶粉的阳离子苯丙乳液的合成

采用种子乳液聚合法,以十六烷基三甲基溴化铵(CTAB)为乳化剂,偶氮二异丁眯盐酸盐(AIBA)为引发剂,引入亲水性阳离子单体甲基丙烯酰氧乙基三甲基氯化铵(DMC)及功能性单体丙烯酰胺(AM)〔m(DMC)∶m(AM)=1∶1〕来制备用于可再分散乳胶粉的阳离子苯丙乳液。探讨了聚合反应温度、乳化剂用量、引发剂用量、种子单体用量、阳离子单体用量等对乳液及可再分散乳胶粉性能的影响。确定最佳配方和工艺条件为:聚合反应温度为(80±2)℃、DMC添加量为2%(以主要聚合单体质量计,下同)、CTAB用量为2%(以单体总质量计,下同)、AIBA用量为0.53%(以单体总质量计,下同)、种子单体用量为10.0%(以单体总质量计,下同)。在该工艺条件下,合成的阳离子苯丙乳液粒径大小和分布适中、性能稳定,由其所制得的可再分散乳胶粉含水率低、平均粒径小、再分散性优良。     

有机硅含量对有机硅-丙烯酸酯微乳液性能的影响

运用非离子复合乳化剂和助乳化剂，通过包壳反应，合成了不同有机硅含量的有机硅．丙烯酸酯微乳液。研究丁有机硅含量对微乳液聚合过程和乳胶膜耐热性能、耐化学腐蚀性能的影响，用DSC和TGA分别测定了乳胶膜的玻璃化转变温度和高温热失重，用TEM测试丁微乳胶粒的粒径分布。结果表明，随有机硅含量增加，乳胶膜的耐热性能和酬化学腐蚀性能明显提高。     

Synthesis and characterization of fluorine-containing poly-styrene-acrylate latex with core–shell structure using a reactive surfactant

Fluorine-containing poly-styrene-acrylate (PSA) latex with core–shell structure was successfully synthesized by seeded semicontinuous emulsion polymerization using fluorine monomer Actyflon-G₀₄ and reactive emulsifier DNS-86. The chemical composition, morphology of latex, and surface composition of the latex film were characterized by Fourier transform infrared spectra, transmission electron microscopy, and X-ray photoelectron spectroscopy, respectively. The stability properties of latex were tested by Ca²⁺, centrifugal and mechanical stability tests, and the latex film was studied by water contact angle, water absorption ratio, and thermo-gravimetric analysis. The results show that fluorine-containing PSA latex particles with crosslinked core and crosslinked shell structure have excellent stability properties, and the film of latex has excellent water repellency, thermal stability, and chemical resistance properties when the amount of fluorine monomer was only 8.0 wt%.     

苯丙乳液改性水泥修补砂浆的制备与性能研究

采用复配技术制备苯丙乳液改性水泥修补砂浆,并进行性能研究.探讨了聚合物乳液、偏高岭土、煅烧膨润土等外加剂对该砂浆物理性能的影响.结果表明:苯丙乳液的掺入虽然在一定程度上降低了砂浆的抗压强度,但显著改善了水泥砂浆的和易性和需水量.通过掺加偏高岭土或煅烧膨润土等火山灰活性掺合料可弥补砂浆力学性能的不足.     

Preparation of organic–inorganic nanocomposites with core‐shell structure by inorganic powders

Organic–inorganic nanocomposites with core‐shell structure were prepared in two steps. In the first step, the latex particles in the semibatch emulsion polymerization of butyl methacrylate (BMA), in the presence of methacrylic acid (MAA), were prepared. Small amounts of acrylic acid incorporated into the latex to have better interaction between the surface of particles and inorganic phase. MAA also increased the latex stability and decreased the amount of coagulum. In the second step, the core‐shell structures were prepared by coating the latex particles with three types of inorganic powders. Pectin coated precipitated calcium carbonate, alumina, and silica. The examinations show that pectin‐coated calcium carbonate has the best response than other types of calcium carbonate. Alumina was the second type of inorganic powder that was used for coating the core particles. Silicagel and fumed silica (Aerosil) were used for coating by silica. Scanning electron microscopy and transmission electron microscopy showed the particle morphology and the core‐shell structure, respectively. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci, 2006     

纳米二氧化硅水性塑料涂料的研制

采用核壳乳液聚合工艺和功能单体对乳液进行改性,制备了具有核/壳结构的苯丙乳液,与纳米二氧化硅复合,得到高性能的啦性纳米复合塑料涂料。介绍其涂膜硬度达到3H以上,耐热在100℃沸水中不回粘,耐水性好、丰满度高的特点。     

Determination of the influence of the polymer structure and particle size on the film formation process of polymers by atomic force microscopy

The particle size and morphology of a synthetic polymer latex were shown to influence the film formation behavior. Theoretical models predict that small particles coalesce more easily than large colloids do.The influence of particle size and morphology of differently structured lattices on the film-formation process was investigated by atomic force microscopy (AFM). Sequences of AFM images were acquired over a certain temperature range or at room temperature as a function of time. From the resulting images the average particle diameter of the latex particles in the surface layer was determined as a function of the time or temperature. The resulting curves could be compared to observe differences in the film formation kinetics of the different lattices. These AFM studies confirmed that the film formation behavior is influenced by the particle size and particle morphology, but that the core/shell ratio of core-shell particles has no significant influence on the film formation kinetics.     

改善废水污泥基外墙涂料透水性的研究

采用废水污泥制备建筑外墙涂料,探讨了石蜡乳液、防水剂、烷基烯酮二聚体(AKD)、丙烯酸酯乳液、绢云母粉和搅拌时间对污泥涂料透水性的影响。结果表明:在防水剂用量3.03%、石蜡乳液用量1.19%、聚丙烯酸酯乳液用量22.70%、绢云母粉用量3.79%和调漆阶段搅拌时间40 min时,污泥涂料的透水性为0.4 mL/24 h,达到了国家标准GB/T 9755—2014对透水性要求;AKD乳液虽可有效降低涂膜吸水率,但与污泥涂料体系中其他组分的相容性差,不宜作为防水组分应用于所研究的涂料体系;适当延长调漆时间,可降低污泥粒子中位径使涂膜较为紧密从而提高涂料抗透水性;污泥涂料膜表面有类似荷叶的乳突状结构,其抗透水能力优于实验中的市售涂料。     

Synthesis and analysis of properties of a new core–shell silicon‐containing fluoroacrylate latex

BACKGROUND: Silicon‐containing fluoroacrylate copolymers are potential materials for use in the protection of ancient stone buildings. In the work reported in this paper, a new core–shell silicon‐containing fluoroacrylate latex was prepared through grafting of a fluoroacrylate copolymer latex with polysiloxane. RESULTS: The core–shell silicon‐containing fluoroacrylate latex was successfully synthesized by seed emulsion polymerization and octamethylcyclotetrasiloxane (D₄) ring‐opening polymerization in the presence of a mixed emulsifier consisting of a non‐ionic emulsifier and a novel fluorine‐containing anionic emulsifier sodium perfluoro‐octane sulfonate. Transmission electron microscopy, X‐ray photoelectron spectroscopy, static contact angle measurements and scanning electron microscopy‐energy dispersive X‐ray analysis showed that when the D₄ content was controlled at 2.84–4.36 wt%, the silicon‐containing fluoroacrylate latex presented a uniform sphere core‐shell structure and had strong hydrophobic and oleophobic characters due to the association of both fluorine and silicon atoms on the latex film surface. The film cross‐section exhibited uniform and dense microstructure without any phase segregation. Additionally, thermogravimetric analysis and tensile test results indicated that all the silicon‐containing fluoroacrylate copolymers displayed better thermal stability and higher flexibility. CONCLUSION: The synthetic core–shell silicon‐containing fluoroacrylate latex showed excellent surface properties, thermal stability and flexibility, and has encouraging prospects in application as a protective coating. Copyright © 2009 Society of Chemical Industry     

核壳结构聚硅氧烷/丙烯酸酯复合乳液(Ⅰ)乳化剂对乳液聚合过程及粒径分布和粒子形态的影响

采用种子乳液半连续法合成了具有高有机硅含量的聚硅氧烷/丙烯酸酯核壳结构复合乳液,研究乳化剂的种类、复配比例及质量浓度对有机硅／丙烯酸酯壳核乳液性能与乳胶粒径、分布和结构的影响.结果表明：阴离子乳化剂十二烷基硫酸钠(SDS)、十二烷基磺酸钠(SDS-2)、十二烷基苯磺酸钠(SDBS)所合成的乳胶粒子粒径依次增大,SDS与非离子型乳化剂OP-10复配使用时,随OP-10质量分数的增加,聚合速率和转化率降低,化学稳定性增加,乳胶粒子粒径增大,分布变宽,确定了复合乳化剂的最佳配比.随复合乳化剂浓度的增加,聚合速率加快、转化率增加,乳胶粒子粒径减小而分布加宽.通过改变乳化剂加入方式可减小乳胶粒子的粒径分布.为减少壳层聚合物新粒子的产生,需严格控制乳化剂的浓度,使加入的壳层单体处于“饥饿”状态,在乳胶粒子表面富集、引发聚合,形成表层“过渡层”,最终形成核壳结构复合粒子.