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1.
负离子型聚氨酯离聚体水分散过程的相反转   总被引:1,自引:0,他引:1  
用异佛尔酮二异氰酸酯、聚己二酸新戊二醇酯和二羟甲基丙酸(DMPA)合成了负离子型聚氨酯离聚体.研究了该类离聚体在水分散过程中的相反转变化,讨论了DMPA质量分数和水分散温度对相反转过程的影响。结果表明,DMPA质量分数增加或水分散温度提高,可使相反转所需的时间缩短,分散液粒子粒径变小,粒径分布更均匀,黏度增大。水分散温度的作用较DMPA更为明显。差示扫描量热分析表明,水分散过程破坏了亲水性硬链段的有序性。傅里叶变换红外光谱分析表明,聚氨酯水分散液用乙二胺扩链后.脲羰基的氢键化程度随DMPA质量分数的增加、水分散温度的提高而提高。  相似文献   

2.
A novel polyurethane material containing zwitterionic sulfobetaine groups has been synthesized using the copper‐catalyzed 1,3‐dipolar cycloaddition (azide‐alkyne click chemistry). A standard two‐step polyaddition method was used to produce the well‐defined polyurethane based on polycarbonatediol (PCDL) with alkyne groups. These polyurethanes containing alkyne units were then efficiently clicked using 3‐((2‐azidoethyl)dimethylammonio)propane‐1‐sulfonate (DMPS‐N3). The novel PU material was characterized by 1H NMR, Fourier transform infrared (FTIR) spectrometer, gel permeation chromatography (GPC), elemental analysis, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and dynamic mechanical analysis (DMA). This facile “click” reaction provides a useful tool for the development of novel functional polyurethanes for biomedical applications. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

3.
聚酯型水性聚氨酯乳液粒径分布及乳液膜耐水性的研究   总被引:2,自引:0,他引:2  
用自制的聚酯伯二醇分别与四甲基苯二甲基异氰酸酯(TMXDI) 或异佛尔酮二异氰酸酯(IPDI)为主要原料,二羟甲基丙酸(DMPA)为亲水单体,水合肼为扩链剂,在DMPA投料相同的条件下,采用预聚体分散法,制备了TMXDI预聚体和IPDI预聚体的水性聚氨酯乳液.利用Autossizer Loc粒度分布仪测定了两种类型乳液的粒径分布.结果表明:TMXDI预聚体与IPDI预聚体水性聚氨酯乳液粒径分布不同,黏度较低的TMXDI预聚体,乳液粒径分布为单峰,均比黏度较高的IPDI预聚体乳液的粒径分布小;对于TMXDI预聚体水性聚氨酯乳液,随预聚体黏度的降低,乳液粒径分布变窄,说明预聚体的黏度对乳液的粒径分布有影响.通过乳液膜耐水性的对比,乳液膜的耐水性与聚酯伯二醇的结构有关.  相似文献   

4.
A new generation multihollow opaque polymer pigment was synthesized by suspension polymerization of “water‐in‐oil‐in‐water” emulsion method, where methyl methacrylate and ethylene glycol dimethacrylate monomer mixture was used as oil phase. The effects of surfactant and cosurfactant composition in terms of “hydrophilic/lipophilic balance” on the stability of the “water‐in‐oil” emulsion and the size of water droplets were studied. Low droplet sizes and the optimum stability were obtained with “Span 80&Tween 80” surfactant mixture at an HLB value of 8. The desired size distribution was obtained at “monomer/surfactant/water” ratio of 75.5/9.4/15.1 at an ultrasonic mixing power of 80 W lasting for 30 s. The surface morphology and hollow structure of polymer pigments were analyzed by scanning and transmission electron microscopy techniques. L*a*b color and gloss properties of polymer pigments were examined. The opacity values were assessed by contrast ratio measurements, and the pigments provided up to 97.3% opacity with 50% v/v solid content in resin. In addition, the pigments exhibited low gloss values and yielded matte films. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43696.  相似文献   

5.
Polyurethane dispersions (PUDs) are one such class of coatings that comply well with stringent VOC regulations. In this study, PUDs were prepared as aqueous dispersions using a new highly versatile crosslinkable anionomer, 2-acrylamido 2 methylpropanesulfonic acid (ATBS), which is commercially available, yet not explored by the coating industry. The influence of this novel anionomer on the performance properties of polyurethane resins was evaluated by comparing performance/properties of this newly synthesized PUD with dispersion based on conventional anionomer, DMPA. Analyses of their physico-chemical and thermo-mechanical properties revealed that PUD based on ATBS showed comparatively much better thermal, mechanical, and chemical and coating properties than the PUD based on DMPA anionomer.  相似文献   

6.
Water‐reducible acrylate copolymer is obtained from a free‐radical copolymerization of n‐butyl acrylate, acrylic acid, and methacrylic acid. Self‐emulsified aqueous‐based polyurethane (PU) anionomer is prepared by the conventional method. The latent curing agents (di‐ and triaziridinyl compounds, HDDA‐AZ and TMPTA‐AZ) are synthesized from the reaction of aziridine with hexandiol diacrylate and trimethylolpropane triacrylate, respectively. These two polymers and the latent curing agent are miscible in each other and become a single component and self‐curable polymer dispersion. The carboxyl ions of polymers not only stabilize the aqueous polymer dispersions but also serve the curing site toward latent curing agent in the drying process. These two polymers blend with a curing agent, which results in new polymer hybrid formation. These polymer hybrids have the improvements on performance properties and the cost/performance benefits. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3578–3587, 2003  相似文献   

7.
室温固化水性聚氨酯树脂的耐水性研究   总被引:1,自引:0,他引:1  
以甲苯二异氰酸酯(TDI)、聚醚多元醇(PTMG)为主要原料,二羟甲基丙酸(DMPA)为亲水单体,采用三羟甲基丙烷脱水蓖麻油酸酯(TMPDCO)进行改性,通过逐步聚合反应制备了一系列室温固化水性聚氨酯树脂。研究了TMPDCO的含量、亲水基团含量、软段多元醇种类与相对分子质量、封端剂以及氮丙啶交联剂等对聚氨酯涂膜耐水性的影响,从而确定了最佳合成配方,获得了优良耐水性能的水性聚氨酯树脂。  相似文献   

8.
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  相似文献   

9.
高性能水性聚氨酯胶粘剂   总被引:31,自引:5,他引:26  
综述了国内外水性聚氨酯进展概况 ,指出亲水性单体引入聚氨酯预聚体后自乳化是目前制备水性聚氨酯的主要方法。结合作者一些实际工作经验探讨了改进和提高水性聚氨酯性能的途径和方法 ,最后对发展我国高性能水性聚氨酯胶粘剂进行了展望  相似文献   

10.
Novel amphiphilic ABA‐type poly(D ‐gluconamidoethyl methacrylate)‐b‐polyurethane‐b‐poly(D ‐gluconamidoethyl methacrylate) (PGAMA‐b‐PU‐b‐PGAMA) tri‐block copolymers were successfully synthesized via the combination of the step‐growth and copper‐catalyzed atom transfer radical polymerization (ATRP). Dihydroxy polyurethane (HO‐PU‐OH) was synthesized by the step‐growth polymerization of hexamethylene diisocyanate with poly(tetramethylene glycol). PGAMA‐b‐PU‐b‐PGAMA block copolymers were synthesized via copper‐catalyzed ATRP of GAMA in N, N‐dimethyl formamide at 20°C in the presence of 2, 2′‐bipyridyl using Br‐PU‐Br as macroinitiator and characterized by 1H‐NMR spectroscopy and GPC. The resulting block copolymer forms spherical micelles in water as observed in TEM study, and also supported by 1H NMR spectroscopy and light scattering. Miceller size increases with increase in hydrophilic PGAMA chain length as revealed by DLS study. The critical micellar concentration values of the resulting block copolymers increased with the increase of the chain length of the PGAMA block. Thermal properties of these block copolymers were studied by thermo‐gravimetric analysis, and differential scanning calorimetric study. Spherical Ag‐nanoparticles were successfully synthesized using these block copolymers as stabilizer. The dimension of Ag nanoparticle was tailored by altering the chain length of the hydrophilic block of the copolymer. A mechanism has been proposed for the formation of stable and regulated Ag nanoparticle using various chain length of hydrophilic PGAMA block of the tri‐block copolymer. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   

11.
Un‐ionized polyurethane was obtained by the reaction of an isocyanate‐terminated urethane prepolymer, which was synthesized from 4,4′‐diphenylmethane diisocyanate and poly(oxytetramethylene)‐α,ω‐glycol, with 2,2‐bis(hydroxymethyl)propionic acid. A carboxylate‐based polyurethane anionomer was then derived from the polyurethane by the use of the sodium, potassium, or magnesium salt of acetic acid as a neutralizer. The ionomerization resulted in the following changes in the characteristics of the polyurethane: (1) an increase in the tensile strength, (2) a decrease in the glass‐transition temperature, (3) an increase in the wettability and hygroscopicity with respect to water, and (4) susceptibility to thermal decomposition. A sulfonate‐based polyurethane was also synthesized for comparison with the carboxylate‐based polyurethane. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 2144–2148, 2005  相似文献   

12.
陈德海  孙东成 《化工学报》2013,64(3):1112-1117
利用乙二胺与双丙酮丙烯酰胺间的Michael加成反应合成了含酮羰基的新型扩链剂N,N'-二双丙酮丙酰胺基乙二胺,用1H NMR和13C MNR证实了结构。聚己二酸新戊二醇酯、异佛尔酮二异氰酸酯(IPDI)、二羟甲基丙酸(DMPA)预聚后加入N,N'-二双丙酮丙酰胺基乙二胺扩链得到含酮聚氨酯预聚物,预聚物经分散、乙二胺扩链后得到聚氨酯分散体。研究了含酮扩链剂用量对分散体及其膜性能的影响。结果表明随N,N'-二双丙酮丙酰胺基乙二胺的增加,聚氨酯分散体的粒径增大、黏度减小。己二酸二酰肼交联后能明显提高WPU胶膜的力学性能。  相似文献   

13.
Acrylic‐based superabsorbent polymers with partial‐neutralized acrylic acid were synthesized by inverse suspension polymerization. The effects of reaction parameters, including the concentration of crosslinking agent and initiator, the neutralization degree of monomer, the monomer concentration, and phase ratio of a system, on the water absorption have been investigated. Furthermore, to improve the properties of salt‐resistance and antielectrolyte for the polymer, acrylamide monomer containing nonionic and hydrophilic groups was introduced into the system, which can suppress the salt effect and homoion effect. The water absorption Q5/3 is proportional to the reciprocal of ionic strength, 1/S, which follows Flory's elasticity gel theory. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 619–624, 2004  相似文献   

14.
A novel monomer, acrylamido (A) tertiary (T) butane (B) sulfonic (S) acid (ATBS) a commercially available ionic moiety was used as a replacement of dimethylol propionic acid (DMPA) in synthesis of polyurethane dispersion. IR technique was used to confirm the chemical structure and formation of polyurethane dispersions. Polyurethane dispersions were investigated for various coating properties, such as drying times, pencil hardness, adhesion, chemical and solvent resistance. Polyurethane dispersion based on ATBS showed better thermal, chemical and coating properties than those prepared by DMPA anionomer.  相似文献   

15.
以自制不同相对分子质最的聚已二酸-新戊二醇酯二醇(PNA型聚酯二醇)和异佛尔酮二异氰酸酯(IP-DI)为主要原料,二羟甲基丙酸(DMPA)为亲水单体,水合肼为扩链剂,制备了IPDI型的水性聚氨酯乳液.研究了PNA聚酯二醇相对分子质量对IPDI型预聚体黏度和水分散性的影响.实验结果表明,将PNA聚酯二醇的相对分子质量控制在1 400以下时,用低相对分子质量的PNA与IPDI的预聚体具有黏度低、易于水分散的特点,可以实现水分散时不加或少加有机溶剂降黏的目的;利用万能材料试验机、XRD、FT-IR和差示扫描量热仪等仪器对所得乳液成膜物的力学性能进行了测试,结果表明:用低相对分子质量的(<1 400)PNA合成的IPDI型乳液的成膜物力学性能可以满足应用的要求.  相似文献   

16.
The field of waterborne polyurethane (WPU) is gaining a great deal of momentum from both a commercial and academic sense because of increasing environmental and sustainable awareness. For polyurethane (PU) to be dispersible in water, the hydrophilic groups are very important in the design of the polymer chains. Herein, we present a design strategy for WPU having hydrophilic groups on the soft segments through the reaction of as‐synthesized OH‐terminated poly(ε‐caprolactone) diols containing a sodium sulfonate group with diisocyanate. A stable aqueous dispersion was then obtained, and this was followed by a subsequent chain extension reaction and emulsification. We found that the PU dispersion particles were a core–shell structure with a good particle size distribution, and the obtained films exhibited a low tensile strength and a high elongation at break. This approach provided valuable information for fundamental research in the production, modification, property enhancement, and new applications of these materials. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39657.  相似文献   

17.
In this study, water‐borne polyurethane resins were produced using poly(propylene‐ethylene) copolymer triol, toluene diisocyanate, and hydrophilic monomers, dimethylol propionic acid and tartaric acid. The hydrophilic monomers were used separately. In either case, the ratio of isocyanate functional groups to the sum of hydroxyl groups of polyol and hydrophilic monomer was kept constant. The increase in the amount of hydrophilic monomer increased the hardness of resins when used as varnish. Tartaric acid resulted in higher hardness than dimethylol propionic acid. The dispersions made by using tartaric acid had much larger particle sizes than those of dimethylol propionic acid. In another set of experiments, the samples carrying the optimum properties from the two sets were mixed with methylol urea that served as crosslinker in the baking step. The physical and mechanical properties were determined by changing the weight percentages of the two types of samples in the mixture, and by changing the methylol urea percentage of the mixture which exhibited the maximum hardness. All samples showed superior impact resistance, adhesion, and flexibility. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 604–612, 2001  相似文献   

18.
Different polyurethane (PU) were synthesized from ε‐polycaprolactone diol, 4,4′‐diphenyl methane diisocyanate (MDI) and bis(2‐hydroxyethyl)terephthalate (BHET), using a two‐step method and a one‐step method providing regular and random distributions of starting monomers in the PU chains. Even with an identical molar monomer composition, the properties of obtained PU are different depending on the method of synthesis. The structure of PU was characterized by 1H and 13C‐NMR and Fourier transform infrared spectroscopy (FTIR). The thermomechanical properties of synthesized PU were also studied demonstrating the influence of aromatic ring in the macromolecular chain. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

19.
A hydrophilic PDMS (polydimethylsiloxane) surface was formed by the synthesis of an interpenetrating polymer network (IPN) in a two‐step process. In the first step, PDMS was loaded with crosslinker and initiator using a solvent that swells the PDMS. In the second step, the PDMS sample was submerged into a solution containing the hydrophilic monomer followed by a UV‐polymerization step. The choice of solvent in the second step is critical to obtain a hydrophilic surface. It can be concluded that the solubility parameter of the solvent should be above a threshold value. Hence, in the second step only sufficiently polar solvents will result in hydrophilic PDMS‐IPNs. These principles are illustrated by using N‐vinyl‐2‐pyrrolidone as the hydrophilic monomer forming PVP/PDMS‐IPNs. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008.  相似文献   

20.
A novel hydrophobic monomer was synthesized from the acetoacetic ester and dodecylamine by condensation reaction in mild conditions. The modification by the dodecyl groups monomer was involved in the Michael addition reaction with acrylic (or methacrylic) acid followed by radical polymerization. Both linear and crosslinked novel betaine‐type polyampholytes bearing hydrophobic “tail” and hydrophilic “head” were obtained. The linear polymer was characterized by viscometry, FTIR, and Raman spectroscopy. Swelling–shrinking behavior of linear and crosslinked samples was studied in water–DMF and water–DMSO mixtures. The applicability of hydrophobically modified polybetaines as pour point depressants (fluidity improvers) was also demonstrated. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1042–1048, 2004  相似文献   

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