含氟丙烯酸酯共聚物细乳液的制备及表征

采用细乳液聚合法,制备了稳定的含氟丙烯酸酯(FA)、甲基丙烯酸甲酯(MMA)和丙烯酸丁酯(BA)的三元共聚细乳液.用FT-IR表征了聚合物的结构组成;考查了细乳液的稳定性、乳胶膜的吸水性及耐溶剂性;用接触角法表征了乳胶膜的表面自由能.     

含氟丙烯酸酯共聚物膜的制备及其表面性能研究

以甲基丙烯酸甲酯(MMA)、丙烯酸六氟丁酯(HFBA)为单体,聚乙二醇甲醚甲基丙烯酸酯(MPEGMA)为可聚合乳化剂,采用无皂反相微乳液聚合法制备了新型含氟丙烯酸酯三元共聚物疏水膜。利用傅立叶红外光谱(FTIR)、扫描电镜(SEM)、X射线衍射(XRD)、接触角测量仪对聚合物膜性能进行表征分析,主要考查了含氟量、乳化剂浓度、成膜方式以及含水量对聚合物膜表面性能及其亲疏水性的影响。结果表明,增加含氟量在一定程度可提高聚合物膜表面的疏水性,MPEGMA侧链结晶有利于含氟基团的表面离析,不同成膜方式影响分子基团的排列、分布及表面粗糙度。     

聚含氟丙烯酸酯/聚氨酯共聚物细乳液的制备及表征

以甲苯二异氰酸酯(TDI)和甲基丙烯酸羟乙酯(HEMA)为原料,合成了丙烯酸酯/聚氨酯(PUA)预聚体;采用细乳液聚合法,合成了聚含氟PUA细乳液。使用红外光谱(FT-IR)和核磁共振(1H-NMR)表征了PUA预聚体及共聚物的结构组成,用激光光散射粒度仪(PCS)分析了乳胶粒的粒径及其分布,并考察了氟单体用量对乳胶膜的吸水率和表面性能的影响。研究结果表明,乳胶粒的粒径随着PUA预聚体用量的增加而增大;当氟单体质量分数由0增至20%时,乳胶膜的吸水率由10.3%降至4.2%,表面自由能由34.89mJ/m2降至15.66mJ/m2,说明氟单体的加入较好地改善了乳胶膜的表面性能。     

全氟丙烯酸酯改性苯丙乳液表面性能

采用两阶段无皂乳液聚合方法,以全氟烷基乙基丙烯酸酯(FAEA)为含氟单体,甲基丙烯酰氧乙基三甲基氯化铵(DMC)为阳离子单体,丙烯酰胺(AM)为亲水单体,在偶氮二异丁腈(AIBN)和2,2-偶氮[2-(2-咪唑啉-2-基)丙烷]二氢氯化物(VA-044)的引发作用下,合成了阳离子型全氟丙烯酸酯改性苯丙乳液。利用FTIR、TGA对共聚物结构和热稳定性进行了表征,分析了氟单体含量和温度对共聚物乳胶膜表面自由能的影响。结果表明,当FAEA含量从1.2%增至5%时,共聚物乳胶膜的表面自由能显著降低,从23.54mJ/m2降至15.27mJ/m2;进一步增加FAEA含量,表面自由能降低缓慢,当FAEA含量为9.8%时,表面能降低到14.83mJ/m2;对共聚物乳胶膜进行退火处理,当温度由25℃升高至120℃时,表面自由能由15.27mJ/m2降低到14.06mJ/m2。     

自交联水性聚氨酯-含氟丙烯酸酯乳液的制备及研究

以异佛尔酮二异氰酸酯(IPDI)、聚碳酸酯二醇(PCDL)、二羟甲基丁酸(DMBA)、1,4-丁二醇(BDO)、甲基丙烯酸羟乙酯(HEMA)为原料合成了双键封端的聚氨酯预聚体;以N-羟乙基丙烯酰胺(HEAA)作交联剂,配合甲基丙烯酸六氟丁酯(HFBMA)等单体进行乳液共聚,制备了自交联水性聚氨酯-含氟丙烯酸酯(FPUA)乳液。研究了HFBMA和HEAA用量对膜耐水性、热性能以及力学性能的影响。结果表明:PUA乳液的耐水性和疏水性随HFBMA用量的增加而增加;随着HEAA用量增加,胶膜的热稳定性增加,拉伸强度增加,伸长率下降;当胶膜中HFBMA质量分数为12%,且HEAA质量分数为2.6%时,乳液的粒径为128 nm,乳液的稳定性较好;胶膜的水接触角为107.6°,吸水率为4.5%,拉伸强度为25.6 MPa,断裂伸长率为268%,10%热失重温度299.6℃。     

环氧树脂-含氟丙烯酸酯-水性聚氨酯杂化乳液的研究

以聚四氢呋喃二醇(PTMG)、异佛尔酮二异氰酸酯(IPDI)、二羟甲基丙酸(DMPA)为主要原料,季戊四醇三丙烯酸酯(PETA)为接枝剂,双酚A型环氧树脂E-44与甲基丙烯酸八氟戊酯(FA)为改性剂,制备了环氧树脂-含氟丙烯酸酯-水性聚氨酯杂化乳液(EWPUFA).通过粒径、红外光谱(FT-IR)、拉伸强度、接触角、吸...     

细乳液聚合制备含氟丙烯酸酯聚氨酯共聚物

采用细乳液聚合法,制备了稳定的含氟丙烯酸酯聚氨酯细乳液。用FT-IR表征了丙烯酸酯聚氨酯预聚体及其共聚物的结构组成;考查了细乳液的稳定性;用透射电子显微镜(TEM)观察了乳胶粒的形态;用接触角法表征了乳胶膜对水和正十六烷的接触角。     

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。     

含氟丙烯酸酯共聚物无皂乳液的粒子形态与性能研究

研究了通过半连续滴加法制备的无皂含氟丙烯酸酯聚合物乳液乳胶粒形态、聚合条件对乳胶粒粒径的影响,测定了乳液性能和乳胶膜的表面性能。制备的含氟乳液的乳胶粒呈圆形,粒径分布窄。乳液稳定性好,含氟乳胶膜对水的接触角为110.2°,吸水率低,表现出优异的表面性能。     

含氟丙烯酸酯改性聚氨酯核壳乳液的制备及表征

以双键封端水性聚氨酯为反应型高分子,全氟丁基磺酸钾为含氟乳化剂,实现甲基丙烯酸甲酯(MMA)、丙烯酸丁酯(BA)、甲基丙烯酸十二氟庚酯(G04)和聚氨酯的共聚,制备具有核壳结构的含氟丙烯酸酯改性聚氨酯乳液(FPUA)。傅里叶变换红外光谱(FTIR)和透射电子显微镜(TEM)对共聚物组成、乳胶粒的形态进行表征,并通过表面接触角、拉伸实验和热重分析等分别研究了FPUA胶膜的表面能、力学性能和热性能。结果表明,当含氟乳化剂和氟单体用量分别为单体总质量的0.15%和20%时,乳液稳定性好,聚合物胶膜表面能由45.6mN/m下降至22.5 mN/m,表现出良好的疏水疏油性,最大热失重速率温度由348℃提高至398℃。     

Effect of hydrophilic monomer on the surface properties of cationic polyurethane‐fluorinated acrylate hybrid dispersions

Cationic polyurethane‐fluorinated acrylate hybrid dispersions (PUFA) were prepared by the copolymerization of styrene, butyl acrylate, and 2,2,3,4,4,4‐hexafluorobutyl methacrylate in the medium of crosslinked polyurethane via phase inversion polymerization. The said polyurethane was synthesized in acetone from 2,4‐tolyene diisocyanate, N‐methyldiethanolamine, trimethylolpropane, and soft polyester diol block. The influences of hydrophilic monomer on the surface properties, immersion behaviors, particle size and, zeta potential of the dispersions were investigated. The results show that the addition of hydrophilic monomer can be advantaged to the stability of dispersions and yet will increase the surface free energy by more than 19.9%. The PUFA coating films cured at ambient conditions have the lower surface free energy (less than 0.02033 J/m²). At the same time, there is an obvious mobility of fluorinated groups in fluorinated polymer films. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci, 2006     

Synthesis and characterization of poly(fluorinated acrylate)/silica hybrid nanocomposites

The nanocomposite particles (NPs) with inorganic silica as core and fluorinated polymer shell have been in situ synthesized via emulsion polymerization. The chemical composition and core‐shell structure were characterized by Fourier‐transform infrared spectrometry and transmission electron microscopy. The results showed that silica nanoparticles were encapsulated in latex particles, with single‐ and multicore morphologies coexisting. Thermal gravimetric analysis also suggested the successful encapsulation of silica into NPs with enhanced thermal stability. The surface properties of the latex films produced from the core‐shell particles were also investigated by contact angle method and water absorption measurement. Both fluorinated polymer and silica contributed to less water absorption ratio and lower surface‐free energy, which was composed of larger polar component and smaller disperse component, just reversed as usual. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Preparation and properties of UV-curable polyurethane acrylate ionomers

Ultraviolet (UV)-curable polyurethane acrylate ionomer (PUAI) prepolymers were synthesized from isophorone diisocyanate (IPDI), poly(methylene ether) glycol (PTMG), 2,2-bis(hydroxymethyl) propionic acid (DMPA), triethylamine (TEA), 2-hydroxy ethyl acrylate (HEA), and dibutyl tin dilaurate (DBT) as a catalyst. UV-curable polyurethane acrylate ionomer aqueous dispersion was formulated from the prepolymers, water (30 wt %), and 1-hydroxycyclohexylhenyl ketone (Irgacure 184) as a photoinitiator. The films of UV-cured polyurethane acrylate ionomer were formed by curing the dispersion using a medium-pressure mercury lamp (80 W/cm; λ max = 365 nm). Gel content decreased with increasing water content in the aqueous dispersion. Effects of DMPA content and molecular weight of PTMG and the degree of neutralization on the physical properties were investigated. It was found that the storage modulus increased with increasing DMPA content. Tensile modulus and strength decreased with increasing the molecular weight of PTMG from 650 to 2000. The glass transition temperature shifted to a higher temperature as the content of DMPA increased. As the degree of neutralization increased, the tensile strength and modulus decreased. However, the elongation at break increased. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 67:2153–2162, 1998     

Effect of crosslinking on the surface free energy and surface reorganization of waterborne fluorinated polyurethane

To endow waterborne fluorinated polyurethanes (WFPUs), films with stable lower surface free energy and lower surface reorganization after the films contacted with water, a series of crosslinked WFPUs (CWFPUs) emulsions were prepared by adjusting the content of aziridine (AZ). The effect of crosslinking on the surface free energy, glass-transition temperature (T _g), water absorption, and surface composition of dry/hydrated WFPUs and CWFPUs films were studied by CAs test, dynamic mechanical analysis, water absorption measurements, and X-ray photoelectron spectroscopy. When the fluorine content was 0.5%, the surface free energy of the CWFPUs films modified by 0.4% AZ content (CWFPU-6-0.5-CK0.4) reached to the lowest value of 15.76 mN m⁻¹ which almost equaled to the surface free energy (15.45 mN m⁻¹) of the dry uncrosslinked films (WFPU-6-0.5). With the increasing of AZ content, the T _{g, hard} of hard segments of the CWFPUs films increased and the water absorption of the CWFPUs films decreased, which suggested the formation of the crosslinked network structures. The studies of the surface elements and groups composition of dry/hydrated WFPUs and CWFPUs both confirmed that the surface reorganization and the migration of fluorinated side chains were restricted by the crosslinked network structures. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47167.     

UV固化蓖麻油基聚氨酯丙烯酸酯/SiO2杂化材料的制备与性能Q

以异佛尔酮二异氰酸酯（IPDI）、蓖麻油（CO）和丙烯酸羟乙酯（HEA）合成了蓖麻油基聚氨酯丙烯酸酯（COPUA），以正硅酸乙酯（TEOS）和3-(异丁烯酰氧)丙基三甲氧基硅烷（MEMO）通过溶胶-凝胶法制备了改性硅溶胶，作为无机相与COPUA有机相复合得到了UV固化COPUA/SiO2杂化材料。调节MEMO与TEOS的配比得到一系列改性硅溶胶，通过测试确定了MEMO与TEOS的最佳配比为1：1（MT-1）。在此基础上，改变MT-1的添加量得到UV固化COPUA/SiO2杂化材料。用FT-IR、TEM、SEM、TGA等对杂化材料和涂层进行结构表征，测试复合涂层的力学性能和表面性能。当MT-1添加量为COPUA树脂质量的15%时，涂层内部SiO2粒子分布均匀，涂层表面光滑平整，光透过率达到100.2%，硬度为5H，附着力0级，柔韧性1mm；涂膜拉伸强度达到13.52MPa，断裂伸长率为7.49%。     

聚氨酯丙烯酸酯/环氧丙烯酸酯分散体系的制备

用水性聚氨酯丙烯酸酯改性环氧丙烯酸酯,制备了聚氨酯丙烯酸酯/环氧丙烯酸酯分散体系。随着分散体中聚氨酯丙烯酸酯浓度的增加,体系稳定性增加,当其浓度达到30%时,可制得稳定的分散体系。这种分散体系可作为一种紫外光固化水性涂料,其涂膜的耐磨性、柔韧性都比环氧丙烯酸酯涂膜增强,而硬度变化不大。     

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。     

PUA复合水分散体的发展

主要从聚合方法和多重复合改性两方面较为系统地介绍了丙烯酸聚氨酯复合水分散体的研究进展。比较了互穿网络法、种子乳液法和原位乳液聚合法等的特点和进展,对多重复合改性如有机硅、纳米材料等的进展作了简介。     

微小乳液聚合制备丙烯酸酯杂化聚氨酯分散液

微小乳液聚合工艺技术在25~30年前即已问世,但用于丙烯酸酯杂化聚氨酯分散液的制备仅有10年历史。用该工艺技术可有效制得稳定的纳米级丙烯酸酯杂化聚氨酯分散液,其性能独特。本文阐述了微小乳液聚合工艺的原理、影响因素、存在问题和解决措施,并以实例说明之。