接枝型PUA乳液合成及聚合动力学研究

甲基丙烯酸羟丙酯与水性聚氨酯预聚体反应,得到双烯封端的水性聚氨酯乳液。在乳化剂、引发剂存在下,将丙烯酸酯单体与水性聚氨酯乳液充分混合,并引发聚合,制备了接枝型PUA乳液。TEM观察了PUA乳液的形貌,PUA乳液的粒径在60～120 nm之间;FTIR和NMR表征了合成的PUA结构,显示丙烯酸酯的加入改变了PU本身的氢键相互作用;转化率测试表明,甲基丙烯酸羟丙酯与PU预聚体的反应具有二级动力学特征,而乳化剂的用量影响丙烯酸酯单体与双烯封端聚氨酯乳液的反应速率,反应速率与乳化剂用量符合Rp∝[SDS]0.28。     

丙烯酸酯改性水性聚氨酯树脂合成工艺的研究

以异氰酸酯、聚醚多元醇及二羟甲基丙酸为主要原料,合成了水性聚氨酯预聚体(PU),并且经过扩链、交联、丙烯酸酯复合改性等反应制备了丙烯酸酯改性水性聚氨酯树脂(PUA)。结果表明:对水性聚氨酯进行扩链、交联及丙烯酸酯复合改性,可以使两者优异的性能有机地结合起来,能显著提高水性聚氨酯的拉伸强度、硬度、耐磨性、耐水耐醇性,从而使水性PUA分散乳液胶膜的性能得到明显改善,以满足水性PUA木器漆用的要求。     

丙烯酸树脂改性水性聚氨酯的结构与性能研究

采用丙烯酸树脂对水性聚氨酯进行改性，得到了共混改性（PU／PA）、共聚改性（PUA’）、接枝改性（PUA）3种丙烯酸改性水性聚氨酯聚合物。通过对改性聚氨酯乳液的激光粒度分析，乳胶膜的红外光谱、热分析、透明性、耐化学性及扫描电镜进行分析，结果表明：改性后的水性聚氨酯，各项性能均有不同程度的提高。在机械共混聚合物PU／PA体系中，聚氨酯分子链和丙烯酸树脂分子链间具有一定的相容性及共混性；在共聚反应聚合物PUA’、PUA体系中，聚氨酯分子链和丙烯酸树脂分子链形成核壳结构，且在PUA中，聚氨酯分子链和丙烯酸树脂分子链之间形成的化学键，可以有效的提高二者的相容性及共混程度。     

Aqueous PUA emulsion prepared by dispersing polyurethane prepolymer in polyacrylate emulsion

Waterborne polyurethane/polyacrylate (PUA) emulsions were prepared by dispersing polyurethane (PU) prepolymer in polyacrylate (PA) emulsion; therefore, the PU particles formed in the presence of PA nanoparticles. The particle size and its distribution of the composite PUA emulsion were determined by dynamic light scattering. The result shows that the average particle size increases initially and then decreases with increasing PA content, which is confirmed by transmission electron microscope characterization. The surface properties of PUA films were analyzed by water contact angle and atomic force microscope topography. It indicates that the water contact angle and the average roughness of the composite PUA films are larger than those of the PU film. Meanwhile, mechanical properties test, scanning electron microscopy, and thermogravimetric analyses disclose that the PUA films are characterized by enhanced tensile strength, rough fractured surface, and good thermal stability. The preparation method proposed in this article is an effective and convenient way to manufacture composite PUA emulsion. The composite PUA emulsion can be potentially used in coatings. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43203.     

阴离子改性PUA紫外光固化胶粘剂的制备及性能

以异佛尔酮二异氰酸酯(IPDI)、二羟甲基丁酸(DMBA)和聚四氢呋喃醚二醇(PTMG)等为主要原料,制得聚氨酯(PU)预聚体;然后将其与丙烯酸羟乙酯(HEA)反应,制得HEA封端的聚氨酯丙烯酸酯(PUA)预聚体;最后在PUA预聚体中加入中和剂等助剂,制备出阴离子改性PUA紫外光(UV)固化胶粘剂。研究结果表明:当w(DMBA中-COOH)=1.2%(相对于PU预聚体质量而言)、中和度=n(中和剂)∶n(DMBA)=80%、以PTMG为多元醇且偶联剂采用预处理法加入时,相应的阴离子改性PUA型UV固化胶粘剂的耐水性、粘接强度和耐久性俱佳。     

Morphology and particle size of nanograde polyurethane/polyacrylate hybrid emulsions

Poly(urethane acrylate) (PUA) composite particles were prepared by seeded surfactant‐free emulsion polymerization. The aqueous polyurethane (PU) dispersions were used as seed particles. The diameters of the seed particles of the aqueous PU dispersions and PUA composite latexes were measured by dynamic light scattering. The microstructures of the PUA composite emulsion particles were observed by transmission electron microscopy. The influences of the amount of the hydrophilic chain extender, the types of initiators, and the PU/polyacrylate (PA) weight ratios on the diameters of the aqueous PU and composite emulsions were also studied. The results showed that the PUA composite emulsions formed a core–shell structure with PU as the shell and with PA as the core. The diameter of the PU seed particles and the particle size of the PUA composite emulsions greatly depended on the amounts of the hydrophilic chain extender used in the preparation of the PU seed; when the hydrophilic chain extender concentration was 7.4%, the average diameter of the PUA composite emulsion particles showed the minimum value. The types of initiators and PU/PA weight ratios did not have a significant influence on the diameter of the PUA composite latex particles. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

PUA／PVC复合乳液树脂的制备及表征

采用甲苯二异氰酸酯（TDI）、聚醚（PPG）和二羟甲基丙酸（DMPA）合成了自乳化阴离子水性聚氨酯（PU），以此为种子制备了聚氨酯／聚丙烯酸酯（PUA）复合乳液，接着在高压釜中进行氯乙烯原位接枝共聚，制备了聚氨酯／聚丙烯酸酯／聚氯乙烯（PUA／PVC）复合乳液树脂。采用激光粒度分析仪、透射电镜、动态热力学分析仪对复合材料的形态及动态力学性能进行了研究。结果表明：PUA／PVC复合胶乳粒子具有多核壳“海岛型”复合结构，经原位改性的PVC复合材料中的PUA橡胶相具有高度均匀的分散性。     

水性聚氨酯/苯丙复合乳液的合成及其在表面施胶中的应用

以N-甲基二乙醇胺(MDEA)为扩链剂制备了水性聚氨酯(PU)乳液,并用其与苯乙烯(St)、丙烯酸丁酯(BA)和丙烯酸羟乙酯混合单体制备了PU/苯丙(PUA)复合乳液,用傅里叶变换红外光谱表征了复合乳液的结构,考察了PU及复合乳液性能的影响因素,并研究了复合乳液的表面施胶性能.结果表明,在-NCO/-OH(摩尔比)为1.7～1.9、MDEA质量分数为10%、中和度为100%的条件下,合成了平均粒径为75 nm左右的水性PU;当反应温度为80 ℃时,PUA复合乳液呈乳白色且无凝胶产生;当BA∶ St(质量比)为1.5～2.0∶ 1.0时,PUA复合乳液的抗水性较好;当BA质量分数由30%增加到40%时,PUA复合乳液的粒径增大,粒径分布变宽;在室温下用质量分数为0.2%的PUA复合乳液对原纸进行表面施胶时,纸张的施胶度达到33%;在105 ℃下,仅需很短的熟化时间下机纸张的施胶度可达95%.     

丙烯酸酯改性水性聚氨酯的合成及应用研究

以异氰酸酯、聚醚多元醇及二羟甲基丙酸(DMPA)为主要原料,合成了水性聚氨酯(WPU)预聚体;然后采用扩链、交联和丙烯酸酯复合改性等方法制备了丙烯酸酯改性水性聚氨酯(PUA)。结果表明:水性PUA具有丙烯酸酯和聚氨酯(PU)的双重优点,而且其低温成膜性较好、综合性能较优、成本及VOC含量较低;由PUA配制的木器漆,其主要性能均达到HG/T36082-1999标准。     

丙烯酸酯改性水性聚氨酯乳液的制备及性能研究

采用物理共混和核-壳聚合法制备了丙烯酸酯改性水性聚氨酯(PU/PA,PUA)乳液,并对不同改性方法制得的乳液进行了研究。通过红外(FTIR)、透射电镜(TEM)、差示扫描量热(DSC)、热重分析(TGA)、耐水性和力学性能测试等研究了丙烯酸酯改性聚氨酯乳液及涂膜的结构与性能。结果表明具有核-壳结构的PUA乳液涂膜耐水性、耐热性和固含量较水性聚氨酯(PU)有明显的提高,力学性能稍有下降;PUA综合性能优于PU/PA。     

Micromorphology and adhesive properties of sulfonated polyurethane/polyacrylate emulsions prepared by surfactant-free polymerization

Novel eco-friendly sulfonated polyurethane/polyacrylate (SPUA) emulsions were synthesized by surfactant-free emulsion polymerization method using PU as seeds. The sodium sulfonate modified polyester polyol (SDNP) was used as internal emulsifier to make the PU emulsion disperse in deionized water. Effects of the SDNP content on the properties of the emulsions and membranes were studied. Dynamic light scattering (DLS) result showed that the average particle sizes of SPUA emulsions decreased first from 124.1 nm to 102 nm when the SDNP content was lower than 40 wt% and then increased to 138 nm. Transmission electron microscopy (TEM) morphology showed that the particle sizes were all spherical and an apparent core-shell structure was observed. Fourier transform infrared spectroscopy (FT-IR) result ascertains that SPUA was successfully prepared. X-ray photoelectron spectroscopy (XPS) analysis demonstrates that the carbon, oxygen, nitrogen, sulfur, and sodium peaks were all revealed and the polyurethane component was rich in the upper surface. Thermo gravimetric analysis (TGA) of the membranes showed that the thermal stability of the SPUA membranes was enhanced by increasing the SDNP content. Scanning electron micrograph (SEM) results demonstrates that the coexistence of a dual phase. The SPUA could be used as adhesives in footwear industry, and the T-peel strength of the SPUA membranes increased from 5.98 N/mm to 12.06 N/mm when the SDNP content was up to 40 wt%. The wettability of SPUA emulsions on the rubber surface results showed that the emulsions could wet the rubber surface well.     

Preparation of UV-curable functionalized graphene/polyurethane acrylate nanocomposite with enhanced thermal and mechanical behaviors

Functionalized graphene nanosheets (f-GNSs) were synthesized by a simple covalent functionalization of graphene with 3-methacryloxypropyl trimethoxysilane (MPTES). The results from FTIR, XPS and XRD showed that MPTES was successfully attached onto the surface of graphene. Functionalized graphene/polyurethane acrylate (f-GNS/PUA) nanocomposites were prepared by UV radiation of PUA with f-GNS. The onset thermal degradation temperature of f-GNS/PUA nanocomposite was increased by 16 °C, at an f-GNS content of 1 wt%. Meanwhile, the storage modulus and glass transition temperature of the nanocomposites were enhanced by incorporating f-GNS into the PUA. This is believed to be attributed to that the covalent functionalization of graphene can improve both the dispersion of f-GNSs in the polymer matrix and the interfacial interactions between f-GNSs and PUA.     

Preparation,mechanical properties of waterborne polyurethane and crosslinked polyurethane‐acrylate composite

The waterborne polyurethane (PU) prepolymer was first prepared based on isophorone diisocyanate, polyether polyol (NJ‐210), dimethylol propionic acid (DMPA), and hydroxyethyl methyl acrylate via in situ method. The crosslinked waterborne polyurethane‐acrylate (PUA) dispersions were prepared with the different functional crosslinkers. The chemical structures, optical transparency, and thermal properties of PU and PUA were confirmed by Fourier transform infrared spectrometry, ultraviolet–visible spectrophotometry, and differential scanning calorimetry. Some physical properties of the aqueous dispersions such as viscosity, particle size, and surface tension were measured. Some mechanical performances and solvent resistance of PUA films were systemically investigated. The experimental results showed that the particle sizes of the crosslinked PUA aqueous dispersions were larger than the PU and increased from 57.3 to 254.4 nm. When the ratios of BA/St, BA/TPGDA, and BA/TMPTA were 70/30, PUA films exhibited excellent comprehensive mechanical properties. The tensile strength and elongation at break of the film were 2.17 MPa and 197.19%. When the ratio of BA/St was 30/70, the film had excellent water resistance and was only 6.47%. The obtained PUA composites have great potential application such as coatings, leather finishing, adhesives, sealants, plastic coatings, and wood finishes. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

蓖麻油和环氧树脂改性水性聚氨酯-丙烯酸酯的合成与表征

以甲苯二异氰酸酯(TD I)、聚醚型多元醇(N210)、2,2-二羟甲基丙酸(DMPA)、甲基丙烯酸甲酯(MMA)等为主要原料,蓖麻油(C.O.)和脂肪族环氧树脂(RE)为交联剂,以原位乳液聚合法制备出聚氨酯-丙烯酸酯(PUA)复合乳液。以无皂乳液聚合法合成了聚丙烯酸酯乳液(PA),再与聚氨酯(PU)乳液机械混合得到PU/PA共混乳液。探讨了蓖麻油C.O.、RE对复合乳液及涂膜性能的影响,烯丙氧基羟丙基磺酸钠(COPS-1)用量对共混乳液和涂膜性能的影响。结果表明,C.O.、RE分别占PU干质量的5.0%～7.0%和2.0%～3.0%,COPS-1占单体总质量的2.0%时,乳液和涂膜综合性能较好。PUA比PU/PA柔韧性好、断裂伸长率高及附着力好,硬度低,成本高。红外光谱分析发现,PUA与PU/PA中—NH—全部形成氢键。TEM观察到,PUA形成核-壳结构的粒子,粒径较小。通过AFM扫描发现,PUA存在硬段与软段的微相分离。     

Waterborne polyurethane and modified polyurethane acrylate composites

Abstract

Waterborne polyurethane (PU) and a series of PU acrylate (PUA) composite dispersions were synthesised from isophorone diisocyanate, polyester polyols, dimethylol propionic acid, hydroxyethyl methyl acrylate, butyl acrylate and methyl acrylate. Fourier transform infrared, ultraviolet visible and differential scanning calorimetry were used to demonstrate structures, optical transparency and thermal stabilities of PU and PUA. The PUA sample had lower glass transition temperature of hard segment and higher decomposition temperature than the PU sample. Performances of the dispersion and film were studied by means of apparent viscidity, particle size and particle size distribution index, surface tension and mechanical property. The results indicated that the solvent resistance and mechanical property of PUA film were improved compared with the pure PU film. The obtained stable PUA composite samples have excellent integrated properties and have a great potential application in meeting the highly diversified demands in modern technologies, such as coatings, leather finishing, adhesives, sealants, rubbers, plastic coatings and wood finishes.     

Hybridization of aqueous‐based polyurethane with glycidyl methacrylate copolymer

The carboxyl group containing aqueous‐based polyurethane (PU) dispersions were prepared from isophorone diisocyanate, poly(propylene glycol)‐1000, and 2,2‐dimethylol propanic acid via a PU prepolymer process. The amino content of this amino‐terminated aqueous‐based PU system was determined by a styrene oxide titration method. Glycidyl methacrylate (GMA) copolymer emulsions were prepared by an emulsion polymerization of GMA and other alkyl acrylates. The curing behavior of the GMA copolymer was demonstrated by a model reaction of the GMA copolymer with ethylenediamine. In the same token, the reaction took place between the PU amino groups and the GMA copolymer epoxides at ambient temperature and resulted in the formation of a hybridized homogeneous copolymer. This hybridized copolymer also consisted of carboxylic acid on the PU fraction after drying. Carboxylic acids of the copolymer were exchanged with calcium ion and this ionic coordination resulted in a calcium ion‐crosslinked copolymer. The physical and mechanical properties and the thermal behaviors of the hybridized copolymers were evaluated. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 71: 903–913, 1999     

单体含量对核壳结构聚氨酯-聚丙烯酸酯乳液性能影响

以水性聚氨酯（PU）为种子乳液,以丙烯酸酯（PA）为聚合性单体,采用种子乳液聚合法合成核壳结构聚氨酯-聚丙烯酸酯乳液（PUA）。研究了单体含量对乳液及胶膜性能的影响。实验结果表明：随着乙烯基单体含量的增加,乳液颜色加深,稳定性下降,胶膜的断裂伸长率降低,硬度和耐水性增加。当乙烯基单体和PU百分比（M／P）为25％时,乳液的稳定性大于12个月,胶膜的断裂伸长率为498％,硬度为0．64,吸水性为22．8％。红外光谱分析表明合成了PUA。     

复合薄膜用水性聚氨酯-丙烯酸酯胶粘剂的合成

以聚醚二元醇、甲苯二异氰酸酯(TDI)、二羟甲基丙酸(DMPA)等为原料合成了聚氨酯预聚体,用丙烯酸羟丙酯(HPA)将其部分封端,制得一种水性聚氨酯丙烯酸酯分散体,再加入乙烯基单体进行自由基引发聚合,制备出水性聚氨酯-丙烯酸酯(PUA)复合乳液。用红外光谱仪(FTIR)、差示量热扫描仪(DSC)、热重分析(TG)、马尔文粒度分析等测试手段,对合成产物进行了结构和性能表征。研究了软硬段质量比、亲水基团含量、丙烯酸酯单体的加入对PUA乳液性能的影响。结果表明,m(软段)∶m(硬段)=2∶1,m(PU)∶m(PA)=4∶1,—COOH质量分数为2.8%,以该乳液配制的胶粘剂应用于包装用CPP/CPP薄膜、OPP/VMOPP薄膜的剥离强度分别达31.9N/m和28.1 N/m。     

Viscoelastic behavior of interpenetrating networks of polyurethane and polyurethane acrylate

The temperature dependence of the dynamic viscoelastic behavior of interpenetrating networks (IPN) of polyurethane (PU) prepared from poly(oxypropylenediol) (POP) and toluylene diisocyanate (TDI), and of polyurethane diacrylate (PUA) prepared from POP and TDI by reacting isocyanate groups of the prepolymer with 2-hydroxyethyl acrylate, was measured in the main transition region. The photoelastic behavior of IPN swollen in dimethylformamide (DMF) and methyl ethyl ketone (MEK) was examined in the rubbery region. The temperature dependences of the dynamic Young modulus E^* of IPN in the concentration range of PUA ≥ 50 vol.% indicate a pronounced two-phase behavior. The effect of the composition of IPN on the temperature dependence of the modulus E^* was quantitatively described by Takayanagi's two-phase model with the conclusion that the PU network is the continuous phase of IPN at ≤ 90% PUA. While in the range of high concentrations of PUA (≥50%) the contributions of phases to E^* are additive within the whole range of temperatures, the thermomechanical behavior at low PUA concentrations (≤40%) is more complex. This finding is interpreted by the existence of an interfacial layer which leads to the loss of the distinct two-phase character of IPN. The higher number of elastically active network chains (EANC) of the PUA network compared with the PU network corresponds to different molecular weights of POP used in the preparation of both components. The nonadditive dependence both of the concentration of EANC and of the stress-optical coefficient on composition confirms the heterogeneous character of the IPN structure.     

蓖麻油聚氨酯-丙烯酸酯复合乳液的合成

采用甲基丙烯酸甲酯（MMA）与蓖麻油水性聚氨酯乳液共聚反应制备聚氨酯丙烯酸酯（PUA）复合乳液,研究了蓖麻油水性聚氨酯性能、MMA添加量、引发剂种类和聚合温度对PUA复合乳液及涂膜性能的影响,并应用傅里叶红外光谱（FTIR）测定反应产物的结构.研究发现,用外观半透明或微透明的PU-M分散液制备的PUA乳液及涂膜性能优良.油溶性引发剂（AIBN）比水溶性引发剂（K₂S₂O₈）更适合本体系的乳液聚合.随着MMA含量增大,PUA复合乳液胶粒粒径增大,黏度减小,涂膜光泽度下降,机械性能变好,耐水性增加.合适的MMA含量为体系总固含量的20%～30%.提出了PUA复合乳液胶粒形成及粒径长大机理.