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1.
Waterborne polyurethane (WPU) was prepared by the reaction of isophorone isocyanate (IPDI), polyether polyol (PTMG1000), dimethylol propionic acid (DMPA), and trimethylol propane (TMP) and 3-aminopropyltriethoxysilane (APTES) as coupling agent. The films of the WPU were prepared by casting emulsions on Teflon surfaces. The structure of the polyurethane (PU) was characterized by Fourier transform infrared spectrometer (FT-IR), thermogravimetry (TG), X-ray diffraction (XRD), and differential scanning calorimeter (DSC). The mechanical properties and solvent absorption of the cast films were also measured quantificationally. FT-IR indicates that –NH2 of APTES reacted with –NCO of PU prepolymer. TG analysis indicates that APTES can improve thermal stability of PU. XRD and DSC show that crystallinity of PU decreased with the increase of w(APTES). It was found that greater mechanical properties of WPU were obtained when chemical networks were formed between PU and APTES. As the mass fraction of APTES increases from 0% to 10%, water absorption decreased from 17% to 8%, ethanol absorption decreased from 46% to 30%. The particle size increases with increase of w(APTES).  相似文献   

2.
Waterborne cationic fluorinated polyurethane (WCFPU) micro-emulsion was prepared by the reaction of isophorone diisocyanate (IPDI), polytetramethyleneether glycol (PTMG1000), 1,4-butanediol (BDO), N-methyldiethanolamine (MDEA), trimethylolpropane (TMP) and perfluoroalkylethyl octanol (FEOH), and then the films of the WCFPU were prepared. The influence on the mechanical properties and water absorption of the films, such as the molar ratio of NCO to OH, the dosage of MDEA, TMP and FEOH, was investigated. Their structure, morphology and heat performance were characterized by fourier transform infared spectrometer (FT-IR), dynamic light scattering (DLS), transmission electron microscope (TEM), X-ray diffraction (XRD), differential scanning calorimeter (DSC) and thermogravimetry (TG). The results revealed that the best mechanical properties and water resistance could be obtained under the condition that NCO/OH molar ratio was 1.25, w(TMP) was 1.1%, w(MDEA) was 7.29% and w(FEOH) was 22.3%. In addition, WCFPU was endowed with low surface energy of its film and the membrane surfaces had excellent water and oil repellency. Furthermore, the thermal stability of the waterborne cationic fluorinated polyurethane increased with the incorporation of perfluoroalkyl chain. And XRD, DSC and TG showed that micro-crystallinity of polyurethane increased with the increase of FEOH, which was benefit to the micro-phase seperation.  相似文献   

3.
Self-crosslinkable polyurethane emulsion containing active carbonyl group was obtained using dihydroxyketon N-[(1,1-dimethyl-2-acetyl)ethyl]-β-dihydroxyethylamino propanamide(DDP) and 1,4-butanediol as chain extenders, isophorone diisocyanate (IPDI), polyether polyol (PTMG1000), dimethylol propionic acid (DMPA) and trimethylol propane (TMP) as main materials, γ-aminopropyltriethoxysilane (APTES) as end capping agent. Then adipic dihydrazide was added into the emulsion. The structure and composition of DDP and the films were confirmed by means of FTIR and 1H nuclear magnetic resonance (1H-NMR) spectrometer, the test results indicated that the reaction between ketone carbonyl and hydrazine has happened during the film curing. The effects of n(NH2NH-)/n(C=O) and DDP content on the properties of the films were studied. The results show that water absorption of the films decreases from 39.3% to 18.9%, crosslinking degree increases from 51.5% to 90.2%, tensile strength increases from 20.1 MPa to 28.3 MPa and pencil hardness is 2H when the DDP content increases from 0% to 6.13%. TGA analysis indicates that the Ketone-Hydrazide crosslinking structure can improve thermal stability of the films.  相似文献   

4.
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  相似文献   

5.
采用半连续法以异佛尔酮二异氰酸酯(IPDI)、聚醚210、二羟甲基丙酸(DMPA)等为聚氨酯原料,甲基丙烯酸甲酯(MMA)和丙烯酸丁酯(BA)为丙烯酸酯类单体,甲基丙烯酸羟丙酯(HPMA)为偶联剂,过硫酸钾(K2S2O8)为引发剂,三羟甲基丙烷(TMP)为交联剂,合成了具有明显核壳结构的丙烯酸酯改性水性聚氨酯(PUA)乳液。通过傅里叶红外光谱和透射电镜对聚合物结构和乳胶粒形态进行表征,并通过接触角(CA)、力学性能测试,差示量热扫描(DSC)和热重分析(TG)等手段研究了乳胶膜的性能。结果显示,当TMP用量为0.8%时,乳胶粒呈核壳结构,乳液稳定性能好,乳胶膜的拉伸强度达到12.5MPa,对水的静态接触角为96°,耐水性和耐热性也有显著提高。  相似文献   

6.
AAS/DMPA对水性聚氨酯胶膜结晶性能的影响   总被引:7,自引:2,他引:5       下载免费PDF全文
曹高华  夏正斌  张燕红  李伟 《化工学报》2013,64(7):2672-2678
以聚己二酸1,4-丁二醇酯(PBA)、六亚甲基二异氰酸酯(HDI)、异佛尔酮二异氰酸酯(IPDI)为主要原料,以混合的乙二胺基乙磺酸钠(AAS)和二羟甲基丙酸(DMPA)为亲水性扩链剂,通过丙酮法合成了固含量为50%的磺酸/羧酸盐型水性聚氨酯(WPU)乳液。采用DSC、XRD、透光率等测试技术表征了AAS/DMPA摩尔比对WPU胶膜结晶性的影响,并从吸水率和热失重两个方面分析了结晶性对胶膜耐水性和耐热性的影响。研究结果表明,随着AAS/DMPA摩尔比的增大,WPU胶膜的结晶性提高,胶膜的耐水性和耐热性在一定程度上得到了改善。  相似文献   

7.
In this study, we report the effect of the DMPA/PTHF molar ratio on dispersion properties of the MDI‐based hydrophilic polyurethane dispersions. In addition, the effect of the DMPA/PTHF molar ratio on the crystallinity and thermal properties of the polyurethane films prepared from dispersions are also discussed. The variation in stability was studied using a particle size analyzer. DSC and XRD analyses were used to study variations in crystallinity of films with the change of DMPA/PTHF molar ratio. FT‐IR spectra were used to monitor the formation of hydrogen bonds through urethane linkages to produce hard‐segment crystalline areas. The zeta potential increased with the increase of DMPA/PTHF molar ratio (hard‐segment content), while particle size of polyurethane particles decreased. Hence, the stability of dispersions was increased with DMPA/PTHF molar ratio due to the increase of hydrophilicity in polymer chain. Crystallinity of the films was increased with DMPA/PTHF molar ratio due to the increase of interchain interactions through Coulombic interactions and hydrogen bonding. Consequently, crystalline melting temperature was increased with the increase of DMPA/PTHF molar ratio. However, molten films formed crystalline soft segments instead of crystalline hard segments during slow cooling. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44475.  相似文献   

8.
In this study, α,ω‐bis(3‐(1‐methoxy‐2‐hydroxypropoxy)propyl)polydimethylsiloxane and α‐N,N‐dihydroxyethylaminopropyl‐ω‐butylpolydimethylsiloxane were used to prepare block and graft waterborne polyureathane–polysiloxane copolymer dispersions. α,ω‐bis(3‐(1‐methoxy‐2‐hydroxypropoxy)propyl)polydimethylsiloxane was synthesized by hydrosilylation, methoxylation and equilibrium reactions; α‐N,N‐dihydroxyethylaminopropyl‐ω‐butylpolydimethylsiloxane was synthesized via hydroxyl protection, alkylation, anionic ring‐opening polymerization, hydrosilylation, and deprotection. Block and graft waterborne polyurethane–polysiloxane copolymer dispersions were prepared by the reaction of poly(propylene glycol) (PPG), toluene diisocyanate (TDI), 2,2‐dimethylol propionic acid (DMPA), 1,4‐butanediol (BDO), α,ω‐bis(3‐(1‐methoxy‐2‐hydroxypropoxy)propyl)polydimethylsiloxane, and α‐N,N‐dihydroxy‐ethylaminopropyl‐ω‐butylpolydimethylsiloxane. The water absorption of block and graft waterborne polyurethane–polysiloxane copolymer films decreased from 163.9 to 40.2% and 17.3%, respectively, when percent of polysiloxane (w/w) increased from 0 to 5%, and the tensile strength of the block waterborne polyurethane–polysiloxane copolymer films decreased while the tensile strength of graft waterborne polyurethane–polysiloxane copolymer films increased with increase of percent of polysiloxane. For graft waterborne polyurethane–polysiloxane films, the tensile strength would decrease when percent of polysiloxane was more than 3%. POLYM. ENG. SCI., 54:805–811, 2014. © 2013 Society of Plastics Engineers  相似文献   

9.
Waterborne polyurethane (WPU) prepolymer was synthesised by the reaction of poly(butylene itaconate) ester (PBI, Mn = 1109 g/mol), 1,6-hexanediol, dimethylol propionic acid (DMPA), 2,4-toluene diisocynate (TDI), hydroxyethyl acrylate (HEA), and absolute ethanol as blocking agent, triethylamine as neutralizer. Cross-linked WPU was synthesized by trimethylolpropane (TMP) as crosslinker. The influences of PBI, DMPA, and TMP content on WPU emulsions and films were investigated. The structure of WPU was determined by Fourier transform infrared (FTIR) spectra, thermal properties and glass transition temperature of WPU films were determined by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC), respectively, and morphology of the emulsion particles was observed by transmission electron microscopy (TEM). Through TGA, the heat resistance of the cross-linked WPU film was better than WPU film. By DSC analysis, glass transition temperature of cross-linked WPU film (21 °C) was higher than WPU film (10 °C).  相似文献   

10.
In this work, a hybrid synthesis technology has been used to fabricate waterborne polyurethane (WPU)/poly(n-butyl acrylate-styrene) (PBS) emulsions with dimethylol-propionic acid (DMPA) as chain extender. The influences of the PBS, styrene, and DMPA contents on the physical properties of the resultant emulsions and cast films have been investigated in detail using various characterization methods. The experimental results show that with an increase in the PBS or styrene content, the particle size in emulsions increases but the viscosity of the emulsions decreases and that the opposite applies for the DMPA content. For cast films, with an increase in the styrene or DMPA content, the tensile strength increases whereas the elongation decreases. The water absorption capacity of the film decreases with an increase in the styrene content or a decrease in the DMPA content. Furthermore, the emulsions synthesized have been used for paper sizing applications. The treated papers exhibit greatly improved water resistance, and the Cobb values at 30 and 60 s are only 10.23 and 11.89%, respectively, of those of unsized papers. The other paper properties, such as gloss, smoothness, folding resistance, and burst strength, are also considerably improved.  相似文献   

11.
Environmentally friendly and lightweight silylated cellulose nanocrystal (SCNCs)/waterborne polyurethane (WPU) composite films that exhibit excellent mechanical properties and water resistance were prepared. The cellulose nanocrystals (CNCs) of the filamentous structure were surface-modified by γ-aminopropyltriethoxysilane (APTES) and then introduced into a castor oil-based aqueous polyurethane (WPU) matrix by in situ polymerization. The morphology and silylation degree of CNCs were characterized by scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and Fourier infrared transform spectroscopy at different APTES concentrations. The results showed that the surface of the nanocellulose crystal has the best silylation morphology and thermal stability with incorporation of 6 wt % APTES. The thermal stability, mechanical properties, surface morphology, and water resistance of the nanocomposites were investigated by TGA, tensile test, SEM and optical contact angle, water absorption test, and mechanical property test after immersed in water. It was found that the effective introduction of modified CNCs resulted in a significant increase in tensile strength at high levels, and the thermal stability and hydrophobicity of the material were improved simultaneously, reaching the percolation threshold at a 0.50 wt % SCNCs as determined theoretically. This study provided an approach to the design and development of surface-modified CNCs/vegetable oil-based polymer composites by using an appropriate concentration of silane coupling agent to modify CNCs and improve the compatibility between nanocellulose and vegetable oil-based polymer matrices. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48228.  相似文献   

12.
有机硅/丙烯酸酯改性水性聚氨酯的合成及性能   总被引:2,自引:1,他引:1  
以异佛尔酮二异氰酸酯(IPDI)、二羟甲基丙酸(DMPA)、聚酯二元醇(XH-111)、丙烯酸羟乙酯(HEA)和3-氨丙基三乙氧基硅烷(KH-550)等为主要原料,分别制得HEA封端和HEA、KH-550共同封端的水性聚氨酯乳液,再加入丙烯酸酯单体进行自由基引发聚合,分别制备出丙烯酸酯改性和丙烯酸酯、KH-550共同改性的水性聚氨酯复合乳液。通过傅立叶变换红外光谱(FTIR)、热失重分析(TGA)、X射线衍射分析(XRD)和力学性能测试,对改性水性聚氨酯乳液的结构和胶膜的热稳定性、结晶性和力学性能进行了考察。结果表明,改性水性聚氨酯的结晶性降低,热稳定性提高。当w(丙烯酸酯)增大到20%,w(KH-550)增大到15%时,胶膜的拉伸强度由5.6 MPa增加到23.9 MPa,断裂伸长率由491%降到247%。  相似文献   

13.
Comb-branched waterborne polyurethane/organo-montmorillonite (CWPU/OMMT) nanocomposites were prepared by in situ intercalating polymerization process based on the main materials including IPDI, DMPA, polycaprolactone diols, comb-branched polymeric diols and OMMT. The average particle size of emulsion increases and the particle size distribution of emulsion becomes broader with the increase of OMMT content. The results of X-ray diffraction (XRD) and transmission electron microscope (TEM) show that OMMT is homogeneously dispersed into the CWPU matrix with intercalated or exfoliated structure. The properties of CWPU/OMMT nanocomposites are dependent on OMMT content. When the OMMT content is 3 wt%, CWPU/OMMT nanocomposite exhibits excellent overall properties: the particle size of emulsion 63.6 nm, tensile strength 42.0 MPa, E′ 20.3 MPa at 80 °C, water absorption 13% at 24 h and surface contact angle for water over 100°.  相似文献   

14.
通过丙酮法以聚碳酸酯二元醇(PCDL)、异佛尔酮二异氰酸酯(IPDI)为原料,双酚AF为改性剂,2,2-二羟甲基丙酸(DMPA)、1,4-丁二醇(BDO)为扩链剂,三乙胺为中和成盐剂合成了一系列不同双酚AF含量改性的水性聚氨酯(WPU)乳液。通过傅立叶红外光谱(FTIR)、X射线衍射(XRD)、热重分析(TGA)、力学性能、表面水接触角、吸水率测试等对聚合物结构与性能进行了表征。结果表明,随着双酚AF含量的增加,WPU薄膜的表面水接触角增大,吸水率降低,耐水性能有所提高;薄膜拉伸强度与断裂伸长率先增大后降低。热重分析结果表明,WPU薄膜的热分解温度随着双酚AF添加量的增加先增大后降低,仍保持良好的耐热性能。XRD分析结果表明,改性前后的水性聚氨酯薄膜均为非晶型,双酚AF的加入对结晶性能并无影响。  相似文献   

15.
Linear polyurethanes based on poly(dl ‐lactic acid) (PDLLA) macrodiol are promising materials in tissue engineering, yet their synthesis requires rigorous control on various parameters. A facile way to prepare linear polyurethanes by capping the PDLLA macrodiol (M n = 4536) with 2‐ureido‐4[1H]‐pyrimidone (UPy) is reported. The obtained low‐molecular‐weight UPy‐capped polyurethane can form flexible, stretchable, and hydrophobic supramolecular films due to the strong and unidirectional quadruple hydrogen bonding of UPy dimers. Tensile tests, shape recovery, and self‐healing observations indicate that, compared with conventional PDLLA macrodiol‐based linear polyurethane (M n = 48840 and PDI = 1.8), the UPy‐capped polyurethane films have comparable mechanical properties (tensile modulus: 900 ± 38 MPa; ultimate strength: 9.6 ± 0.8 MPa) yet significantly better shape memory and self‐healing properties. These results suggest that the UPy‐capped polyurethane might become an alternative for conventional linear polyurethane as a new biomedical material.  相似文献   

16.
Trimethylol propane (TMP), polyglycol (PG), and toluene diisocyanate (TDI) were reacted in various molar ratios to produce TMP–TDI–PG–urethane prepolymers and then mixed with equivalent isocyanate generator (Desmodur AP-Stable) in a mixture of m-cresol and naphtha to give polyurethane varnishes which finally became crosslinked films by the casting method. The mechanical properties and viscoelasticities of the PG-modified and PG-free polyurethane crosslinked films and the practicability of magnet wires coated with them were studied in this article. Three different PGs used in this experiment were polyethylene glycol, PEG(#400), polypropylene glycols, PPG(#1000) and PPG(#2000). In the case of adding PEG(#400) for modification, strength at break increased but elongation did not change. Meanwhile, glass transition temperature (Tg) shifted to lower temperature with increasing molar ratio. In the case of adding PPG(#1000) and PPG(#2000) for modification, the samples changed their mechanical properties from hard and brittle to soft and tough. With increasing molar ratios, strength at break initially increased and then decreased gradually, and elongation varied a lot and was consistently contrary to strength at break. Tg occurred at two regions: one at high temperature above 100°C for small molar ratios and the other at low temperature below 100°C for high molar ratios. Besides, for all PG-modified polyurethane crosslinked films, strength at break showed a local maximum at TMP/TDI/PG = 1/1/0.5, which indicated their homogeneous structures. The molar ratios of PG-modified urethane prepolymers, which are suitable for manufacturing practical magnet wires according to testing method JIS-C-3211, are as follows: TMP/TDI/PPG(#100) = 1/1/0.15–0.35 and TMP/TDI/PPG(#2000) = 1/1/0.10. PEG(#400)-modified magnet wires were not accepted on the aging test. The properties of crosslinked films of practical magnet wires are generally as follows: strength at break at 200–700 kg/cm2, elongation less than 41%, and Tg at 100–200°C.  相似文献   

17.
The polyurethane prepolymer was synthesized, and hydrophilic nano-sized silica (A200) was added to the prepolymer with KH550 as a coupling agent, then a waterborne polyurethane/nanosilica hybrid material (WPUNS) was obtained by a sol-gel process. The structure and performance of the WPUNS films were studied by FTIR, TG, DSC and physical mechanical testing. The particle size and distribution of WPUNS hybrid emulsion was analyzed by a dynamic light scatter (DLS). The morphology of emulsion and films were observed by Transmission Electron Microscope (TEM) and Atomic Force Microscope (AFM), respectively. FTIR analysis indicates the formation of chemical bond between WPU and A200. TEM images display that A200 particles were encapsulated by PU macromolecules and formed a composite particles structure. As the mass fraction of A200 increased from 0 to 2%, the particle size increased from 79.9 nm to 139.9 nm, the tensile strength of the films increased from 6.32 MPa to 20.46 MPa, water absorption decreased from 28.3% to 6.3%, and the hardness was also improved. The TG result indicates that A200 can improve thermal stability of WPUNS. DSC shows that there is no clear effect of nanosilica on the glass transition of soft segments. AFM displays that the smoothness of the films increases with A200 addition.  相似文献   

18.
Stable water‐borne polyurethane dispersions (PUDs) were prepared from bifunctional aliphatic polycarbonate‐based macrodiol, 2,2‐bis(hydroxymethyl)propionic acid (DMPA), 1,6‐diisocyanatohexane, 1,4‐butanediol (BD), and triethylamine. Water‐borne dispersion particles are thus solely formed from self‐assembled linear PU chains. Both PUDs and PUD‐based films were characterized with regards to the concentration of DMPA (ionic species content) and BD (hard‐segment content). Average particle size of PUDs decreased and their long‐term stability increased with increasing DMPA and decreasing BD concentration. Functional properties of cast films made from PUDs are substantially influenced by the character of the original colloidal particle dispersions. The swelling behavior of the films, their surface morphology, and mechanical properties are more influenced by DMPA than BD contents. At DMPA concentrations higher than 0.2 mmol g?1 of the solid mass of polyurethane, distinct self‐organization of individual nanoparticles into fibril‐like structures was detected by atomic force microscopy and scanning electron microscopy. PU films made from PUD containing high BD as well as high DMPA concentrations have the best utility properties namely sufficient tensile properties and a very low swelling ability. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42672.  相似文献   

19.
A number of aqueous polyurethane dispersions based on polytetramethylene glycol (PTMG), 1,4-butanediol (1,4-BDO), dimethylol propionic acid (DMPA) and diisocyanates of differing structures such as toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), isophorone diisocyanate (IPDI), and dicyclohexylmethane diisocyanate (H12MDI) were prepared. IR Spectroscopy was used to check the end of polymerization reaction and also the polymer characterization. The effects of diisocyanate structure on the particle size, contact angle, mechanical and thermal properties of the emulsion-cast films were studied. Average particle size of prepared polyurethane emulsions change by different diisocyanate based polyurethane. TDI based PU shows higher average particle size and contact angle than the others. Tensile strength, hardness, and elongation at break were higher in the case of MDI based polyurethane. Thermal property and thermal stability is also affected by variation of diisocyanate molecular structure.  相似文献   

20.
郭悦  强涛涛 《精细化工》2021,38(5):1061-1067
采用异佛尔酮二异氰酸酯(IPDI)、聚四氢呋喃醚二醇2000(PTMG2000)为原料,二月桂酸二丁基锡、1,4-丁二醇和2,2-二羟甲基丙酸分别为催化剂、小分子扩链剂和亲水单体,制得水性聚氨酯预聚体(PPU);接着以丙烯酸甲酯、二乙醇胺和三羟甲基丙烷为原料合成了超支化聚(胺-酯)(HPAE);最后制备出不同HPAE含量(以IPDI与PTMG2000的总质量为基准,下同)的支化型水性聚氨酯(WPU)胶黏剂.采用FTIR和1HNMR对HPAE及胶黏剂的结构进行了表征;通过TGA、多功能材料试验机考察了胶膜的热力学性能和机械性能.结果表明,HPAE用量为IPDI与PTMG2000的总质量的1.0%时,制备的WPU2乳液及胶膜综合性能较好,其乳液固含量为33.67%,胶膜吸水率为11.22%,水接触角为90.32°;胶膜机械拉伸强度为10.33 MPa,断裂伸长率为533.73%;其粘结性能良好,剥离强度为4.063 N/mm.  相似文献   

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