共查询到20条相似文献,搜索用时 31 毫秒
1.
采用磺酸盐聚醚二元醇(SPPG)和聚乙二醇单甲醚(PEOM)为亲水单体,聚碳酸酯二醇(PCDL)、聚四氢呋喃二醇(PTMG)、异佛二酮二异氰酸酯(IPDI)、乙二胺(EDA)为原料,通过预聚体法制备了固含量50%以上的聚氨酯分散体(PUD)。研究表明,PUD的ζ电位处于-45~-65 mV之间,分散体稳定性优异。平均粒径处于80~140 nm之间,粒径多分布于60~200 nm范围内,磺酸盐基团的增加使胶粒平均粒径变小,粒径分布变窄;NCO/OH摩尔比和PCDL的增加使胶粒平均粒径趋于变大,[JP+2]粒径分布变宽。透射电镜(TEM)显示,分散体胶粒呈大小不一的球形结构。PUD的黏度随剪切速率的增加而下降,呈现假塑性流体的特征。 相似文献
2.
3.
The UV-curable hyperbranched urethane acrylate oligomers modified with different fatty acids including undecylenic acid (UCA), myristic acid (MA), and oleic oil (OA) are successfully synthesized in this paper. The prepared oligomers are characterized using FTIR, 1HNMR, GPC, DSC, and TGA. The properties of the UV-curable films formed by these oligomers are also determined. The effects of the oligomer structures including double bond content, chain length of the modified fatty acids, and content of fatty acid and polyurethane acrylate segment, on the properties of the cured films, which are tack-free time, pencil hardness, impact resistance, adhesion, and boiling water resistance, are discussed in detail. It is observed that the curing film formed by HBPE2-60%UCA-20%PUA shows the best comprehensive performance among the films prepared in this study. 相似文献
4.
Polyurethane dispersions (PUDs) have been an active area of research since the early 1940s because of legislative restrictions on the use of organic solvents in conventional solvent‐based products and also because PUDs exhibit almost the same high performance levels as solvent‐borne polyurethanes. In the present study, properties of conventional waterborne PUDs are modified with epoxy‐acrylic graft copolymer blocks. The epoxy‐acrylic graft copolymers were first modified with ethylene diamine to give amine‐terminated blocks which in turn reacted with isocyanate‐terminated prepolymer (prepolymer mixing process) to give modified PUDs. Several experimental sets were prepared with varying compositions. The experimental sets were also prepared using conventional poly(ethylene glycol) blocks and ethylene diamine chain‐extenders. The physico‐chemical properties and film characteristics of the experimental sets show the dramatic improvement in important mechanical properties of PUDs due to grafting with epoxy‐acrylic copolymer blocks. Copyright © 2004 Society of Chemical Industry 相似文献
5.
《国际聚合物材料杂志》2012,61(1-4):21-27
Abstract Nylon 6, 6 oligomers, obtained from industrial wastes, were used for modifying an unsaturated polyester resin, creating a series of semi-interpenetrating polymer networks (semi-IPN's) with different compositions. The oligomer was dissolved in the resin by heating. Then, the modified polyester was crosslinked at room temperature. The tensile strength, impact strength and thermal properties of the prepared semi-IPN's are reported. A relationship between the mechanical properties and thermal characterization with the developed morphology of the semi-IPN's was established. 相似文献
6.
以磺酸盐聚醚二元醇(SPPG)作为软段亲水单体,DMPA作为硬段亲水单体,聚己二酸己二醇新戊二醇酯(PHNA)、异佛尔酮二异氰酸酯(IPDI)、六亚甲基二异氰酸酯(HDI)、三乙胺(TEA)、哌嗪为原料,采用丙酮法合成了固含量50%以上软硬段均含亲水的聚氨酯分散体(PUD)。研究表明,PUD的ζ电位处于-52~-72mV之间,具有良好的稳定性。亲水基团含量(HGC)、HDI/IPDI摩尔比的增加使胶粒平均粒径变小,粒径分布变窄,黏度增加;—SO3Na/—COOH摩尔比的减小,使小粒子体积分数在21%~28%,黏度显著减小。透射电镜(TEM)显示,分散体胶粒多为大小不一的球形结构,呈多元分布。DMA显示PUD胶膜具有良好的软硬段相容性和耐寒性。 相似文献
7.
8.
以聚醚多元醇、聚酯多元醇和蓖麻油为混合多元醇,以改性MDI(4,4′-二苯基甲烷二异氰酸酯)及PAPI(多亚甲基多苯基多异氰酸酯)为混合异氰酸酯,合成了聚氨酯(PU)胶粘剂预聚体;然后以PA(羟基丙烯酸酯树脂)作为PU预聚体的改性剂,制得高固含量的PUA(聚丙烯酸酯改性聚氨酯)胶粘剂。结果表明:当m(改性MDI)∶m(PAPI)=1∶1、n(-NCO)∶n(-OH)=2.2∶1、w(PA)=8%(相对于PU质量而言)和w(丙烯酸羟乙酯)=3%(相对于PU质量而言)时,PUA胶粘剂的综合性能较好。 相似文献
9.
以聚酯二醇、改性二苯基甲烷二异氰酸酯为原料制备预聚体,丁二醇为扩链剂,用预聚体法制备中高硬度聚氨酯弹性体。考察了预聚体贮存稳定性,以及制备方法对综合物性的影响。实验结果表明,该体系配方具有可行的加工性能,制品的物理性能优良;预聚体可贮存一定时间,预聚体法制得的弹性体性能比一步法好。 相似文献
10.
Hui Du Yuhua Zhao Ning Yin Qifeng Li Junwei Wang Maoqing Kang Hongwei Xiang Xinkui Wang 《应用聚合物科学杂志》2008,110(5):3156-3161
Waterborne polyurethane (WPU) adhesives modified by polystyrene (PS) were prepared through a prepolymer mixing process from diisocyanates, an anionic polyester, internal emulsifiers, a neutralizer, a chain extender, and PS dispersions. The latter was preformed via the in situ polymerization of styrene in poly(1,4‐butanediol adipate) diol. Transmission electron microscopy, Fourier transform infrared spectroscopy, and 1H‐NMR techniques were used to characterize the PS dispersions and polyurethane (PU)–PS prepolymer. Experimental results with respect to the performance of the PU–PS adhesives indicate that suitable PS/polyester diol weight ratios improved the mechanical properties, thermal stability, water resistance, and initial adhesive strength of the pristine WPU adhesives. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
11.
短链含氟丙烯酸酯对水性聚氨酯的改性研究 总被引:2,自引:1,他引:2
以甲苯二异氰酸酯(TDI)、聚酯二元醇(PBA)、二羟甲基丙酸(DMPA)和丙烯酸羟乙酯(HEA)等为主要原料,采用内乳化法制备出双键封端的水性聚氨酯(CCWPU);然后以该CCWPU作为甲基丙烯酸三氟乙酯(TFMEA)的大分子乳化剂,并与之发生共聚合反应,得到含氟水性聚氨酯(FPU)乳液。采用红外光谱(FT-IR)法、动态激光光散射(DLLS)法及静态接触角法等测试手段,研究了合成工艺、TFMEA用量等对FPU乳液粒径、耐水性能和接触角等影响。结果表明:当w(引发剂)=0.5%、反应温度为80℃和反应时间为4h时,随着TFMEA用量的增加,FPU胶膜对水的接触角由58°左右增至92.5°,FPU乳液的粒径从53nm增至96nm,FPU的耐水性能明显提高,并且经FPU乳液处理过的棉布具有超疏水性能。 相似文献
12.
Three model structures of linear segmented anionomeric polyurethanes based on perfluoropolyether dimethylol‐terminated oligomers, isophorone diisocyanate, and dimethylol propionic acid were synthesized and obtained in the form of aqueous dispersions. The structures differed from each other in the chemical nature of the chain extender (diol or diamine) and in the content of carboxylic acid. Dispersions and polymer films were characterized by dynamic light scattering, dynamic mechanical analysis, differential scanning calorimetry, and contact angle measurements. Diluted aqueous dispersions were also evaluated as protective sizing agents in paper treatment, both as bulk modifiers and as surface treatments. Paper sheets characterized by high water and oil repellence were obtained. The results showed that performance is mainly related to the ionic group content of the polymer and to its molecular architecture. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1364–1372, 2005 相似文献
13.
Side-chain polyesters and polyester hydrochlorides were synthesized from α-(bis(2-hydroxyethyl)amino)-ω-(4′-methoxy biphenyl-4-oxy) alkanes with different spacer lengths (Cn-diol, n=6, 8, 10) and terephthaloyl chloride. Since N-substituted diethanolamine acts as a stronger acid acceptor than triethylamine or pyridine, polyester hydrochlorides are formed during polyesterification instead of polyesters. Polyesters can be prepared from a chloroform solution of polyester hydrochlorides by extraction of HCl. During the polyesterification, linear polymers as well as cyclic oligomers are formed. All polymers were analyzed by 1H NMR, size exclusion chromatography (SEC), differential scanning calorimetry (DSC), X-ray spectroscopy (XND) and polarizing optical microscopy (POM). Polyesters and polyester hydrochlorides differ greatly in solubility and thermal properties. Although no liquid crystalline phase transitions were detected for either kind of polymer, an ordered structure was observed in XRD experiments for both polymers and was ascribed to a crystal smectic E phase. 相似文献
14.
Variability in fatty acid compositions of peanuts imported from six different countries into the United States were studied to determine their effect on processing and storage conditions. The oil content ranged from 44.1 to 50.4%. Major fatty acids, palmitic acid (C16:0), oleic acid (C18:l), and linoleic acid (C18:2) ranged from 8.6 to 12.7, 35.9 to 61.1 and 21.7 to 44.2%, respectively. Oleic and lino-leic acids together comprised ca. 78.0–83.0% of the total fatty acids. Highly significant differences (P<.01) in fatty acid compositions were obtained between samples and between locations (countries of origin). Indicators of stability of the peanut samples as measured by the oleic/linoleic acid ratio (O/L) and iodine value (IV) of the extracted peanut oils showed variable but significant differences (P <.05) between locations. Generally, higher O/L ratios corresponding to lower IV indicate better stability and longer shelf-life of the samples. 相似文献
15.
采用异佛尔酮二异氰酸酯(IPDI)、聚酯二元醇(聚己二酸-1,4丁二醇酯)(PBA)为主要原料合成了环氧改性的、固体分约为50%的水性紫外光固化聚氨酯分散体(PUD)。通过预聚物中聚氨酯分子末端的—NCO基团与丙烯酸羟丙酯(HPA)和季戊四醇三丙烯酸酯(PETA)上的羟基发生反应,从而引入碳碳双键,使PUD具备紫外光固化的性能。研究了水性UV分散体的碳碳双键对水性聚氨酯的拉伸强度、硬度、粒径等性能方面的影响,同时对涂膜进行动态力学性能测试(DMA)和断面结构表征(SEM)。结果表明:双键含量增加,UV涂料的拉伸强度和硬度增大,分散体和涂料的其他性能基本不变;DMA测试表明随着双键含量的减小,软段的T_g(s)移向低温,硬段的T_g(h)移向高温,相分离趋于完全;SEM测试表明树脂的交联程度越大,抵抗断裂的程度也越大。 相似文献
16.
Synthesis and ultraviolet‐curing behaviors of vinyl ether functionalized polyurethane oligomers
下载免费PDF全文
![点击此处可从《应用聚合物科学杂志》网站下载免费的PDF全文](/ch/ext_images/free.gif)
The vinyl ether functionalized oligomer is one of the most basic components of vinyl ether functionalized materials for cationic UV‐curable coatings. In this study, three types of vinyl ether functionalized polyurethane oligomers (i.e., polyether, polyester, and polydimethylsiloxane) were synthesized with diisocyanate, diol, and hydroxyethyl vinyl ether. These oligomers were characterized by IR, 1H‐NMR, and 13C‐NMR spectroscopy. The effect of the raw material ratio on the oligomer, UV‐curing behaviors, and thermal properties of these oligomers were investigated. The UV‐curing behavior was analyzed by real‐time Fourier transform infrared spectroscopy. The vinyl ether terminated polyester urethane oligomer exhibited better UV curing, with a higher final conversion and maximum UV‐curing rates. In addition, the light intensity was enhanced for oligomers with better UV‐curing properties. Research on these vinyl ether functionalized oligomers is essential to the development and applications of cationic vinyl ethers systems. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40501. 相似文献
17.
以聚酯二元醇为软段、异佛尔酮二异氰酸酯(IPDI)和N-甲基二乙醇胺(N-MDEA)为主要原料,采用丙酮法合成了高固含量(约50%)的CWPU(阳离子水性聚氨酯),并着重探讨了N-MDEA含量、软段种类对该CWPU的基本性能、结晶性能、力学性能和粘接性能等影响。结果表明:当w(N-MDEA)=5.5%~7.0%(相对于预聚体质量而言)时,可制得稳定的高固含量CWPU;软段的结晶性越好,高固含量CWPU的力学性能和粘接性能越高;当软段为聚己二酸己二醇酯(PHA)时,相应高固含量CWPU的邵A硬度(84)、拉伸强度(55 MPa)和剥离强度(初始剥离强度、24 h剥离强度为68.2、90.4 N/25 mm)相对最大,可作为胶粘剂使用。 相似文献
18.
介绍了聚酯聚合物多元醇以及大分子分散剂端羟基预聚体、巯基改性聚酯多元醇和顺丁烯二酸酐(MA)改性聚酯多元醇的制备方法,对合成聚酯聚合物多元醇所需的原料提出了具体要求。聚酯聚合物多元醇用于制备聚氨酯软质泡沫具有一定的价格优势。 相似文献
19.