含氟丙烯酸酯核壳乳液的制备与性能研究

以甲基丙烯酸甲酯(MMA)、丙烯酸丁酯(BA)为主单体,分别加入丙烯酸六氟丁酯(HFBMA)和甲基丙烯酸十二氟庚酯(DFHM)作为聚丙烯酸酯改性剂,制备了2种含氟丙烯酸酯核壳乳液。采用1H-NMR、TEM、DSC、EDS-SEM、Zeta电位及纳米激光粒度仪等表征了乳胶粒子的组成、结构、粒径及其分布以及乳胶膜表面氟元素的含量。研究了2种含氟单体的用量对乳液稳定性、乳胶膜吸水率、单体转化率、乳胶膜表面疏水疏油性等的影响;研究结果表明:DFHM的改性效果明显好于HFBMA。当DFHM的加入量为4%时,乳胶膜对水的接触角达到93.5°,吸水率降为11.54%,对正己烷的接触角达到82.0°;乳胶粒子的平均粒径70.02 nm,粒径分布窄(PDI=0.082),且具有核壳结构;SEM-EDS测试结果显示,制备的含氟聚合物在成膜过程中,氟元素更易向表面迁移,从理论的5.70%上升到13.47%,从而使乳胶膜具有更好的疏水和疏油性能。     

可交联型含氟嵌段共聚物的ATRP法制备及其在疏水涂膜中的应用

研究采用ATRP法制备了可交联型含氟嵌段共聚物P(MMA-HEMA-BMA)-b-PFMA,并考察了选择性溶剂的种类和成膜温度对聚合物胶束形态、涂膜表面微观结构形貌、涂膜疏水性和综合性能的影响。研究结果表明:在THF、DMF、F113、TFPE中含氟嵌段共聚物均能形成核壳结构胶束,胶束溶液成膜后涂膜表面具有一定微观粗糙结构。当以TFPE为溶剂,成膜温度为80℃时,含氟官能团能迁移到含氟嵌段共聚物的表面,涂膜表面的静态水接触角最大为135.2°,涂膜附着力为1级,硬度为HB,表现出优良的综合性能。     

成膜温度对共混乳胶膜梯度结构的影响

将平均粒径相近的含氟丙烯酸酯乳液（FAE）与丙烯酸酯乳液（AE）按质量比1:1共混,再将共混乳液分别于15℃、30℃、45℃、60℃下在聚四氟乙烯板（PTFE）上成膜。通过红外光谱（FI-IR）、粒度分布（PSA）、接触角（CA）、表面自由能、原子力显微镜（AFM）、扫描电镜（SEM）结合电子能谱（SEM-EDX）、X光电子能谱（XPS）、力学性能研究了成膜温度对共混乳胶膜自组织梯度结构和表面性能的影响。结果表明,FAE乳液与AE乳液共混后,共混乳液粒径降低,分布变宽。共混乳液成膜温度高于45℃时,膜断面出现相分层,F-P（膜-聚四氟乙烯基材）面的含氟组分浓度开始高于F-A（膜-空气）面,含氟组分在F-P面富集,具备纯含氟丙烯酸酯聚合物表面性能,F-A面氟组分含量少,其主要是丙烯酸酯聚合物组分。氟元素浓度从F-P面到F-A面减少,膜梯度结构及两面异性更显著。随温度的升高,乳胶膜的拉伸强度有显著的增大。     

阳离子可聚合乳化剂制备含氟核壳无皂乳液

采用半连续种子乳液聚合技术制备阳离子含氟核壳无皂乳液,对影响乳液聚合反应稳定性的主要因素进行探讨和优化;通过红外光谱(FT-IR)、核磁共振氢谱(1H-NMR)、透射电镜(TEM)、X射线光电子能谱(XPS)、接触角测量仪表征共聚物化学组成、乳胶粒形貌、共聚物膜表面化学元素及其疏水性。结果表明,顺丁烯二酸–乙酯撑基[三甲基氯化铵]–十八烷基聚氧乙烯(20)醚酯(R303)用量为总单体质量3%,引发剂偶氮二异丁基脒盐酸盐(VA-50)用量为总单体质量0.7%,氟单体为总单体质量16.5%,反应温度T为70℃时,可以制得稳定的阳离子含氟核壳无皂乳液。FT-IR及1H-NMR测试结果证明氟单体完全参与共聚,TEM和XPS表征结果表明乳胶粒具有核壳结构,且氟元素在乳液成膜过程中容易迁移到涂膜表面并富集。与传统乳液聚合所得乳液相比,涂膜疏水性有一定提高。     

成膜温度对共混乳胶膜梯度结构的影响

将含氟丙烯酸酯乳液(FAE)与丙烯酸酯乳液(AE)共混,得共混乳液BE-1,将BE-1分别于15、30、45、60℃下在聚四氟乙烯板(PTFE)上成膜。通过FTIR、粒度分布(PSA)、接触角(CA)、表面自由能、AFM、SEM-EDS、XPS和力学性能测试考察了成膜温度对共混乳胶膜自组织梯度结构和表面性能的影响。结果表明,BE-1平均粒径是73.30 nm,PDI为0.133,与FAE乳液相比,BE-1粒径减小,粒径分布变宽。BE-1成膜温度高于45℃时,膜断面出现相分层,F-P(膜-聚四氟乙烯基材)面的含氟组分质量分数开始高于F-A(膜-空气)面,含氟组分在F-P面富集,具备纯含氟丙烯酸酯聚合物表面性能,F-A面氟组分含量少,F-A面主要是丙烯酸酯聚合物组分。氟元素质量分数从F-P面到F-A面逐渐减少,在成膜温度分别为45和60℃时,F-P面F元素质量分数比F-A面高3.59%和10.00%。60℃时,乳胶膜BE-1拉伸强度达到了11.66MPa,比15℃成膜的乳胶膜提高了63.99%。     

含氟丙烯酸酯乳液高疏水性与低氟含量的平衡探索

为了研究含氟丙烯酸酯乳液涂膜的疏水性与氟含量的平衡关系,以甲基丙烯酸十二氟庚酯(DFHM)为含氟单体,双丙酮丙烯酰胺(DAAM)和己二酸二酰肼(ADH)为交联单体,采用半连续核壳乳液聚合的方法合成了一系列自交联含氟丙烯酸酯共聚物乳液。研究表明:含氟单体含量为12%(即氟含量为6.84%,均以聚合单体的总质量计,下同)时,含氟基团在涂膜表面可以达到饱和,乳液固含量可达38.2%;再添加4%交联单体,涂膜的水接触角为116.6°。当含氟单体含量降为4%(氟含量2.28%)时,通过提高成膜温度或添加成膜助剂,也可使涂膜表面的水接触角达到104.2°,具有较好的疏水性能。     

核壳型含氟丙烯酸酯共聚乳液

以十二烷基硫酸钠（SDS）和壬基酚聚氧乙烯基醚（OP-10）为复合乳化剂，甲基丙烯酸十二氟庚酯（Actyflon-God）、甲基丙烯酸甲酯（MMA）、丙烯酸丁酯（BA）为原料制备了壳层含氟的核壳型丙烯酸酯共聚物乳液。用红外光谱（FT—IR）表征乳胶膜化学组成，用透射电子显微镜（TEM）观察了乳胶粒的微观形态结构，并用X射线光电子能谱（XPS）进行了表面分析。发现氟有向空气与膜面迁徙的现象。通过吸水率表征含氟丙烯酸酯共聚物乳胶膜的表面性能，结果表明含氟量增加使乳胶膜吸水率大大降低。     

PVA作用下含氟丙烯酸酯共聚乳液的制备与表征

以聚乙烯醇(PVA)为乳化剂,采用Fe2+-H2O2引发体系,以全氟烷基乙基甲基丙烯酸酯(FM)、丙烯酸丁酯(BA)、苯乙烯(St)、甲基丙烯酰氧乙基三甲基氯化铵(DMC)、丙烯酸羟乙酯(HEA)为主要单体进行乳液聚合,制得了阳离子含氟丙烯酸酯多元共聚物乳液。通过FTIR、1HNMR、透射电镜(TEM)、示差扫描量热(DSC)及接触角测试对共聚物结构、乳胶粒径及形态、乳胶膜表面性能进行了研究。结果表明,该乳液的粒子形态呈球形,单分散性良好,平均粒径为90～100nm;随着共聚物中含氟单体质量分数的增加,乳胶膜的表面自由能显著降低;退火处理有助于含氟基团迁移到乳胶膜表面,乳胶膜表面自由能进一步降低。     

微波辐射强化制备含氟硅丙烯酸酯共聚物乳液

采用多步种子乳液聚合法,以丙烯酸丁酯、甲基丙烯酸甲酯、g-(甲基丙烯酰氧)丙基三甲氧基硅烷和甲基丙烯酸六氟丁酯为原料在微波辐射下制备了核-壳型含氟硅丙烯酸酯共聚物乳液. 并研究了共聚物的结构、乳胶粒的形态和聚合过程中粒径的变化. 结果表明,所得乳胶粒子呈核-壳结构,与常规加热相比,微波的引用能加快反应速率,形成核-壳结构. 壳层富集含氟硅聚合物的核-壳形态有利于含氟硅结构单元在聚合物膜表面的分布,当氟硅单体为6%(w)时,乳胶膜对水的接触角达91.3o. 加入氟硅组分显著提高了聚合物膜的耐水性,当其含量从0增大到18%时,乳胶膜的吸水率从20.1%降低到3.54%.     

自交联含氟乳胶膜耐介质性能的研究

用种子乳液聚合法制备了具有核壳结构的含氟乳液，从FTIR、TEM的表征来看，得到了性能较好的、具有核壳结构的含氯乳液。通过测试含氟乳胶膜的耐介质性，并运用JC2000A静态接触角测量仪测定乳胶膜的接触角，研究了FBA（甲基丙烯酸含氟酯）用量、FBA加入方式、NMA（N-羟甲基丙烯酰胺）用量、乳化剂用量对含氟乳胶膜耐介质性的影响。结果表明，配方中FBA用量为20％（孽尔分数）、NMA用量为4％（质量分数）、乳化剂用量2．8％（质量分数），而且将FBA全部放在壳层聚合，可得到性能较住的含氟乳胶膜。     

核壳型纳米SiO2/含氟聚丙烯酸酯复合乳液的合成与表征

采用原位乳液聚合法,在可聚合阴离子乳化剂/非离子乳化剂复配体系下,以γ-甲基丙烯酰氧丙基三甲氧基硅烷(KH-570)改性的纳米SiO2、甲基丙烯酸甲酯(MMA)、丙烯酸丁酯(BA)、丙烯酸(AA)等为核相组成,以MMA、BA及甲基丙烯酸十二氟庚酯(DFMA)为壳相单体,合成纳米SiO2/含氟聚丙烯酸酯复合乳液.考察了纳...     

阳离子型含氟丙烯酸酯共聚乳液的微波辐射制备

在微波辐射下,以十八烷基三甲基氯化铵为乳化剂,2,2-偶氮2甲基丙基脒-二盐酸盐（AIBA）为引发剂,将丙烯酸丁酯（BA）、甲基丙烯酸甲酯（MMA）、甲基丙烯酸十二氟庚酯（GO-4）以及甲基丙烯酰氧乙基三甲基氯化铵（DMC）进行乳液聚合,成功制备了Zeta电位在315mV左右、粒径为55~75nm的阳离子型含氟丙烯酸酯乳液。通过测定乳胶膜中氟元素含量,发现微波辐射能提高含氟单体共聚效率,使乳胶膜中氟元素含量增加。用固含量1％的阳离子型含氟丙烯酸酯共聚物乳液处理棉布织物,结果发现,棉布对水和正十六烷的接触角可分别达到111．3°、60．6°,表面自由能降至1581mJ／m2,棉布的静态吸水时间可以超过4h。     

Emulsifier-free core-shell polyacrylate latex nanoparticles containing fluorine and silicon in shell

The emulsifier-free core-shell polyacrylate latex nanoparticles containing fluorine and silicon in shell were successfully synthesized by emulsifier-free seeded emulsion polymerization with water as the reaction medium. The silicon-containing fluorinated polymer could be fixed on the surface of polyacrylate nanoparticles due to the formation of the crosslinked network structure. Transmission electron microscopy (TEM) and dynamic light scattering (DLS) analysis indicated that the obtained emulsifier-free core-shell nanoparticles were uniform and possessed narrow size distributions. The core-shell structure and chemical components of the emulsifier-free core-shell nanoparticles were investigated by TEM and Fourier transform infrared (FTIR) spectrometry, respectively. X-ray photoelectron spectroscopy (XPS) analysis and contact angle measurement on the latex films proved the propensity of fluorine and silicon enrichment at film-air interface. In addition, the thermal stability of the latex films was improved with increasing the concentration of fluorine and silicon.     

Preparation and characterization of silica sol/fluoroacrylate core–shell nanocomposite emulsion

The silica sol/fluoroacrylate core?Cshell nanocomposite emulsion was successfully synthesized via traditional emulsion polymerization through grafting of KH-570 onto silica particles. Comparing the performance of the polyacrylate copolymer, the fluorinated polyacrylate copolymer and the silica sol/fluoroacrylate core?Cshell nanocomposite emulsion, we can come to a conclusion that the silica sol/fluoroacrylate core?Cshell nanocomposite emulsion presents significantly excellent performance in all aspects. The products were characterized by Fourier transform infrared (FTIR), photon correlation spectroscopy (PCS), transmission electron microscopy (TEM), thermogravimetry (TGA), Contact angle and UV?Cvis analyses techniques. The chemical structure of polyacrylate copolymer, fluorinated polyacrylate copolymer and silica sol/fluoroacrylate nanocomposite were detected by FTIR. The size and stability of emulsion latex particles were determined by PCS technique. TEM analysis confirmed that the resultant latex particle has the core?Cshell structure, obviously. The water absorption and contact angle data also showed that the silica sol/fluoroacrylate nanocomposite film has good hydrophobic performance. TGA analysis indicated the weight loss of the silica sol/fluoroacrylate nanocomposite film begins at around 350?°C which testifies its good thermal stability. The UV?Cvis spectroscopy analysis showed that the silica sol/fluoroacrylate nanocomposite film possess UV?Cvis shielding effect when the added volume amount of KH570 modified silica sol is up to 5?mL. Therefore, the excellent properties of hydrophobicity, thermodynamics and resistance to ultraviolet provide the silica sol/fluoroacrylate nanocomposite film with potential applications in variety fields. In addition, the formation mechanism of core?Cshell structure silica sol/fluoroacrylate nanocomposite latex particles was speculated.     

核-壳结构含氟丙烯酸酯乳液的合成与表征

A fluorine-containing polyacrylate copolymer emulsion was synthesized by a seed emulsion polymerization method, in which methyl methacrylate （MMA） and butyl acrylate （BA） were used as main monomers and hexafluorobutyl methacrylate （HFMA） as fluorine-containing monomer. The structure and properties were characterized by Fourier transform infrared spectrum （FT-IR）, transmission electron microscopy （TEM）, particle size analysis, X-ray photoelectron spectroscopy （XPS）, contact angle （CA）, differential scanning calorimetry （DSC） and thermogravimetry （TG） analysis. The FTIR and TEM results showed that HFMA was effectively involved in the emulsion copolymerization, and the formed emulsion particles had a core-shell structure and a narrow particle size distribution. XPS and CA analysis revealed that a gradient concentration of fluorine existed in the depth profile of fluorine-containing emulsion film which was richer in fluorine and more hydrophobic in one side. DSC and TG analysis also showed that a clear core-shell structure existed in the fluorine-containing emulsion particles, and their film showed higher thermal stability than that of fluorine-free emulsion.     

硅溶胶/含氟聚丙烯酸酯复合乳液的制备与表征

采用经典的St(o)ber法在常温下制备纳米级硅溶胶,用3-(甲基丙烯酰氧)丙基三甲氧基硅烷对其改性.在阴离子乳化剂和非离子乳化剂共同存在下,通过乳液聚合制备了硅溶胶/含氟聚丙烯酸酯复合乳液.表征了乳胶粒形貌,测试了共聚物组成及性能、乳液稳定性和乳胶膜性能.结果表明:乳胶粒有明显的核壳结构,乳液有良好的储存稳定性、稀释稳定性、高温和低温稳定性;硅溶胶/含氟聚丙烯酸酯复合乳胶膜吸水率达12.50％,对水的接触角为93 5°;复合物的热稳定性高于普通聚丙烯酸酯共聚物和含氟聚丙烯酸酯共聚物.     

细乳液聚合制备纳米SiO2／含氟丙烯酸酯复合乳液及其性能研究

采用溶胶-凝胶法,以正硅酸乙酯为前驱物,在丙烯酸酯单体为油相介质中原位生成纳米SiO2粒子,并通过细乳液聚合,制备出纳米Si02／含氟丙烯酸酯复合乳液。研究了含氟单体和SiO2的用量对复合乳胶膜性能的影响,并采用FT-IR,DSL等分析手段对产物进行了表征。结果表明：该乳液具有良好的稳定性,粒径分布较窄。当（甲基丙烯酸十二氟庚酯）FA与SiO2的用量分别为6％和5．5％时,乳胶膜表现出良好的疏水性能,对水的接触角达到了102．7°,吸水性降低到6．9％。     

Preparation of fluorinated polyacrylate composite latex with in situ generated nano-silica dispersion and film durability

Nano-silica dispersion was generated in situ through the hydrolysis and condensation of tetraethyl orthosilicate with methyl methacrylate and butyl acrylate in micelles as dispersing media, hydrochloric acid as catalyst and methacryloxypropyl trimethoxysilane as modifier. Then, the nano-silica/fluorinated polyacrylate composite latexes were prepared via emulsion polymerization directly using the in situ generated nano-silica dispersion as seeds. Dodecafluoroheptyl methacrylate (DFHMA) as functional monomer was incorporated into shell layer of the composite particles by semi-continuous starved condition at the second stage. Fourier transform infrared spectroscopy indicated that silica was generated in situ and DFHMA took part in the copolymerization. Transmission electron microscopy showed uniform composite latex particle morphology and obvious core–shell structure. Dynamic light scattering demonstrated that DNS-86 could control the composite latex particle size ranging from 90 to 180 nm. DFHMA had an important effect on the particle size. Zeta potential (ζ) revealed that the composite latex had good stability. The resulted composite films were characterized by angle-resolved X-ray photoelectron spectroscopy, contact angle measurements and thermo-gravimetric analysis. The well-tailored composite latex particle structure of nano-silica core and fluorinated polyacrylate can effectively improve the hydrophobicity of the resultant films. Water contact angle could reach 123.5° when 6 wt% DFHMA was incorporated in the film. Moreover, water contact angles remained 106° after water immersion in the range of the experimental sample films. In addition, the incorporation of fluorinated monomer and nano-silica contributed to the improvement of thermal stability of the composite film.     

自制反应性乳化剂制备的含氟核壳乳液及性能

采用烷基酚聚氧乙烯醚（OP-10）与顺丁烯二酸酐反应,制得反应性乳化剂;以甲基丙烯酸甲酯（MMA）和丙烯酸丁酯（BA）为核,甲基丙烯酸甲酯（MMA）、丙烯酸丁酯（BA）和甲基丙烯酸十二氟庚酯（DFMA）为壳,采用半连续种子乳液聚合方式制备核壳型含氟丙烯酸酯乳液。对反应性乳化剂的性能进行了初步探究,并通过红外光谱、TEM、DSC、CA、TGA等对体系进行了研究。结果表明,自制的反应性乳化剂性能优异,合成的乳胶粒具有典型的核壳结构,乳液性能稳定;反应性乳化剂的引入使涂层具有较低的表面能,有效地提高了乳胶膜的疏水性能。     

纳米SiO2/聚氨酯-含氟丙烯酸酯杂化乳液的合成与表征

采用种子乳液聚合法,以聚氨酯（PU）乳液为种子（在聚合过程中为壳相）,甲基丙烯酸甲酯（MMA）、丙烯酸丁酯（BA）、甲基丙烯酸十二氟庚酯（DFMA）和γ-甲基丙烯酰氧丙基三甲氧基硅烷（KH-570）改性的纳米SiO₂组成的混合物为核相,合成了具有核壳结构的纳米SiO₂/聚氨酯-含氟丙烯酸酯（SiO₂/FPUA）复合乳液。考察了纳米SiO₂和DFMA用量对乳液聚合过程及乳胶膜性能的影响。通过傅里叶红外光谱（FT-IR）、接触角（CA）、透射电子显微镜（TEM）、热重（TG）、差示扫描量热仪（DSC）和力学性能测试（MPT）等表征乳液的结构形态、乳胶膜的表面性能和综合性能。结果表明：乳胶粒子呈现“反相核壳”结构,以聚丙烯酸酯（PA）相为核,PU相为壳;由于纳米SiO₂和DFMA的协同作用,涂膜的疏水性和综合性能得到了较大的提高。