Characterization Of Novel Polyurethanes Research Articles

Synthesis and characterization of novel polyurethanes, polypyridazine, and polyamide based on s‐1,2,4,5‐tetrazine

AbstractThe synthesis and analysis of new polymeric materials based on 1,2,4,5‐tetrazine are discussed in this study. Tetrazine was mixed with thermoplastic polyurethane in dimethylformamide (DMF) as solvent and dibutyl tin dilaurate as catalyst at 50°C for 24 h to create brush polyurethane‐urea, which was then reacted with an unsaturated center in dimethyl sulfoxide as solvent at 60°C for 48 h made of either polyenol or thermoplastic polyurethane through π–π interaction. Because 1,2,4,5‐tetrazine (red color) is known to act as an electron‐deficient dine in inverse electron demand Diels–Alder reactions and can be easily converted to pyridazine (peach color) via [4 + 2] cycloaddition with suitable followed by expulsion of molecular nitrogen (cycloreversion), we observed a highly colored red shift to peach and this monitor for this reaction. Additionally, polyamide was prepared via reaction of 3,6‐diamino‐1,2,4,5‐tetrazine with terephthaloyl chloride in DMF as a suitable solvent and triethylamine as basic catalyst at 0°C for 3 h and then 36 h at room temperature. The new polymers that were produced were elucidated by spectral data.

イオン液体構造を主鎖骨格に有する新規なポリウレタンの合成とその特性

イオン液体構造を主鎖骨格に有する新規なポリウレタンの合成とその特性

Synthesis and Characterization of Novel Polyurethanes Based on Vegetable Oils Amide and Ester Polyols

Amide and ester type polyols were synthesized from rapeseed, sunflower and castor oils, and two types of ethanolamine (diethanolamine and triethanolamine) at different molar ratio. Poly(urethane amides) and polyester urethanes based on the synthesized polyols were prepared. The effect of the chemical structure of the obtained polyurethanes on density, glass transition temperature, thermal stability and mechanical properties was investigated. The influence of the content of OH groups in the synthesized polyols on the specified characteristics was estimated. It has been found that poly(urethane amides) have better mechanical characteristics, but their thermal stability is lower than that of polyester urethanes. The chemical structure of the synthesized polyols and polyurethanes is qualitatively confirmed by IR-spectroscopy data. DOI: http://dx.doi.org/10.5755/j01.ms.20.3.4532

Synthesis and Characterization of Novel Polyurethanes Based on Tall Oil

Amide and ester type polyols were synthesized from different kinds of tall oil and two types of ethanolamine (diethanolamine and triethanolamine). Poly(urethane amides) and polyester urethanes based on the synthesized polyols were prepared. The influence of the chemical structure of the obtained polyurethanes on density, glass transition temperature, thermal stability, mechanical properties and adhesive strength was investigated. The effect of the content of rosin acids in original tall oil on the specified characteristics was estimated. It has been found that poly(urethane amides) have higher mechanical characteristics, but their thermal stability is lower than that of polyester urethanes. The chemical structure of the synthesized polyols and polyurethanes is qualitatively confirmed by IR-spectroscopy data.DOI: http://dx.doi.org/10.5755/j01.ms.19.4.2666

Preparation and characterization of novel polyurethanes containing 4,4′-{oxy-1,4-diphenyl bis(nitromethylidine)}diphenol schiff base diol

Four novel segmented polyurethanes (PUs) based on4,4′-{oxy-1,4-diphenyl bis(nitromethylidine)}diphenol (ODBNMD) diol with different diisocyanates such as 4,4′-diphenylmethane diisocyanate, toluene 2,4-diisocyanate, isophorone diisocyanate, and hexamethylene diisocyanate have been prepared by solution method. The structures of ODBNMD and PUs have been confirmed by Fourier transform infrared (FTIR), nuclear magnetic resonance (1H-NMR and 13C-NMR), UV-visible, and fluorescence spectroscopies. The segmented PUs were further characterized by thermogravimetry (TGA), differential scanning calorimetry (DSC), and wide-angle X-ray diffraction. FTIR confirmed hydrogen bonding interactions, whereas TGA and DSC suggested that introduction of aromatic/phenyl ring in the main chain considerably increased the thermal stability. POLYM. ENG. SCI., 54:24–32, 2014. © 2013 Society of Plastics Engineers

Synthesis and Characterization of Novel Polyurethanes Based on N,N'-1,2-Ethanediylbis-(4-Hydroxy-Pentanamide) and 4-Hydroxy-N-(2-Hydroxyethyl)-Pentanamide

As diols, N,N'-1,2-ethanediylbis-(4-hydroxy-pentanamide) (1) and 4-hydroxy-N-(2-hydroxyethyl)-pentanamide (2)) are versatile precursors for the manufacture of bio-polymers. Polymer design, by exploiting the variation in structure of both diol and di-isocyanate monomers, such as backbone structure and presence of functional groups, appears to be a promising biopolymer engineering pathway to synthesize polyurethanes. Both diols (1) and (2) were then polymerized by reaction with aliphatic and aromatic di-isocyanates at 140 °C in (N,N-dimethylacetamide (DMA) solvents using triethylamine (TEA) catalysts, to obtain novel polyurethanes. The products were characterized by FTIR, 1H-NMR, 13C-NMR, and Elemental Analysis. This working has created a new chance to synthesis bio-polyurethanes based on levulinic acid, as one of biomass compounds

Synthesis and characterization of novel polyurethanes based on fluorine‐containing polyphosphazene

AbstractFluorine‐containing poly[bis‐(2,2,3,3,4,4,5,5‐octafluoro‐1‐pentanol)1.6 (4‐hydroxybutaneoxy)0.4 phosphazene] (OFHBP) was synthesized and characterized by Fourier transform infrared (FTIR) spectra, nuclear magnetic resonance (NMR), and gel permeation chromatography (GPC). The obtained OFHBP was used as a cross‐linker to prepare a series of novel polyurethanes (PUPFs). The composition of the PUPFs was confirmed by FTIR and elemental analysis (EA). The crystalline structure and microstructure of the PUPFs were examined by X‐ray diffraction (XRD) and atomic force microscopy (AFM). The thermal and tensile properties of the PUPFs were characterized by differential scanning calorimetry (DSC) and tensile testing. In addition, the surface energy of the PUPFs was also evaluated by contact angle measurements (CA). The results showed that glass transition temperature of the PUPF‐4 was decreased by 15°C, elongation at break was improved by 61% and a 41% decrease in surface energy in comparison with conventional polyurethane. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

Synthesis and characterization of novel polyurethane crosslinked by linear oligo[bis‐(phenoxy)1.8(4‐hydroxybutaneoxy)0.2 phosphazene

AbstractLinear oligo [bis‐(phenoxy)1.8 (4‐hydroxybutaneoxy)0.2 phosphazene] (OPHBP) was synthesized and characterized by Fourier transform infrared spectroscopy, nuclear magnetic resonance, and GPC. The obtained oligo [bis‐(phenoxy)1.8 (4‐hydroxybutaneoxy)0.2 phosphazene] was used as crosslinker to prepare a series of novel polyurethanes. Their structure and properties were measured through Fourier transform infrared spectroscopy, thermogravimetric analysis, differential scanning calorimetry, and water contact‐angle measurement. Compared with conventional polyurethane, novel polyurethanes exhibited better thermal stability, low temperature resistance, and hydrophobicity. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

Synthesis and characterization of novel polyurethanes based on aminolysis of poly(ethylene terephthalate) wastes, and evaluation of their thermal and mechanical properties

AbstractBACKGROUND: Much research is currently directed towards recycling post‐consumer poly(ethylene terephthalate) (PET) products for both environmental and economic reasons. Aminolysis of PET wastes using different amines, such as allylamine, morpholine, hydrazine and polyamines, leads to different reaction products as diamides of terephthalic acid, which do not possess any potential for further chemical reactions. In the past, the use of ethanolamine has been investigated for the aminolytic degradation of PET waste in the presence of different simple chemicals such as sodium acetate as catalysts. The product obtained, bis(2‐hydroxyethylene) terephthalamide (BHETA), has potential for further reactions to obtain useful products. Nevertheless, there has been no report on using recycled BHETA from PET to synthesize polyurethanes.RESULTS: In this research the product of aminolysis of PET waste, BHETA, was prepared. Then novel polyurethanes were synthesized based on the BHETA prepared, 1,4‐butanediol, ether‐type polyol and various molar ratios of hexamethylene diisocyanate. To evaluate the effect of BHETA, the properties of the polyurethanes without and with BHETA were compared. Fourier transform infrared spectra, thermal transitions, degradation, swelling ratio and chemical resistance of the synthesized polyurethanes were investigated. Also, the polyurethanes were applied as adhesives on various substrates. Comparison of the maximum bond strength of the synthesized polyurethane to that of commercial adhesives shows an about 2.2‐fold increase.CONCLUSION: It is possible to synthesize new polyurethanes with interesting properties using BHETA as an aminolysis product of PET waste. These kinds of materials have potential for many applications, such as adhesives and coatings. Copyright © 2008 Society of Chemical Industry

Synthesis and characterization of novel polyurethanes based on N1,N4‐bis[(4‐hydroxyphenyl)methylene]succinohydrazide hard segment

AbstractThis article deals with the synthesis and characterization of novel polyurethanes (PUs) by the reaction between two aromatic diisocyanates (4,4′‐diphenylmethane diisocyanate and tolylene 2,4‐diisocyanate) and two aliphatic diisocyanates (isophorone diisocyanate and hexamethylene diisocyanate) with N1,N4‐bis[(4‐hydroxyphenyl)methylene]succinohydrazide, which acted as hard segment. UV–vis, FTIR, 1H NMR, 13C NMR, and DSC/TGA analytical technique has been used to determine the structural characterization and thermal properties of the hard segmented PUs. X‐ray diffraction revealed that PUs contained semicrystalline and amorphous regions that varied depending upon the nature of the backbone structures. PUs were soluble in polar aprotic solvents. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008

Synthesis and characterization of novel polyurethanes based on 4-{(4-hydroxyphenyl)iminomethyl}phenol

Four novel polyurethanes were prepared from 4-{(4-hydroxyphenyl)iminomethyl}phenol by reactions with two aromatic diisocyanates, 4,4′-diphenylmethane diisocyanate and toluene 2,4-diisocyanate, and two aliphatic diisocyanates, isophorone diisocyanate and hexamethylene diisocyanate. The polyurethanes formed were characterized by UV-vis, fluorescence, FT-IR,1H-NMR,13C-NMR, differential scanning calorimetry, thermogravimetry, and X-ray diffraction. The polymers were semi-crystalline and all polymers were soluble in polar aprotic solvents.

Synthesis and characterization of novel polyurethanes based on 4,4’-{1,4-phenylenebis[methylylidenenitrilo]}diphenol

A series of novel segmented polyurethanes (PUs) containing imine units in the main chain were prepared by polyaddition reaction of various diisocyanates like 4,4’-diphenyl-methane diisocyanate, tolylene 2,4-diisocyanate, isophorone diisocyanate and hexamethylene diisocyanate with 4,4’-{1,4-phenylenebis[methylylidenenitrilo]} diphenol based diol. The structure of the diol and segmented PUs were determined by Fourier transform infrared, ultraviolet-visible spectrometry and fluoroscence spectroscopy. PUs were soluble is polar aprotic solvents. Thermal properties were done by using differential scanning calorimetry (DSC) and thermogravimetric analysis. DSC data display the PUs having multiple endotherm peaks. MDI based PU show the more thermal stable compared to other PUs.

Synthesis and characterization of novel polyurethanes based on 4,4′-[1,4-phenylenedi-diazene-2,1-diyl]bis(2-carboxyphenol) and 4,4′-[1,4-phenylenedi-diazene-2,1-diyl]bis(2-chlorophenol) hard segments

Eight novel polyurethanes (PUs) based on 4,4′-[1,4-phenylenedi-diazene-2,1-diyl]bis(2-carboxyphenol) and 4,4′-[1,4-phenylenedi-diazene-2,1-diyl]bis(2-chloro- phenol) as hard segments with four diisocyanates viz., 4,4′-diphenyl-methane diisocyanate, toluene 2,4-diisocyanate, isophorone diisocyanate and hexamethylene diisocyanate were prepared. Structural and thermal characterization of the segmented PUs were determined by FT-IR, UV spectrophotometry, fluoroscence spectroscopy, 1H NMR, 13C NMR spectroscopy and DTA/TGA analysis. All the PUs contain domains of semi-crystalline and amorphous structures, as indicated by X-ray diffraction. PUs were soluble in polar aprotic solvents like N-methyl-2-pyrrolidone (NMP), dimethyl formamide (DMF) and dimethylsulfoxide (DMSO).

Synthesis and characterization of novel polyurethanes based on 2,6‐bis(4‐hydroxybenzylidene) cyclohexanone hard segments

AbstractFour novel polyurethanes (PUs) containing 2,6‐bis(4‐hydroxybenzylidene) cyclohexanone hard segments with four diisocyanate, namely, 4,4′‐diphenylmethane diisocyanate, toluene 2,4‐diisocyanate, isophorone diisocyanate, and hexamethylene diisocyanate, were prepared. Structural elucidation and thermal characterization of these PUs were done by Fourier transform infrared, UV, and fluorescence spectroscopy, 1H‐NMR, 13C‐NMR, and differential thermal analysis/thermogravimetric analysis. All of the PUs contained domains of semicrystalline and amorphous structures as indicated by X‐ray diffraction. PUs were soluble in polar aprotic solvents such as N‐methyl‐2‐pyrrolidone, dimethylformamide, and dimethyl sulfoxide. Acoustic properties were calculated from the group contribution method. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007

Novel polyurethane elastomer continuous carbon fiber composites: Preparation and characterization

AbstractPreparation and characterization of novel polyurethane (PUR)–carbon fiber (CF) composites are reported. The reinforcement of PUR elastomers was achieved using unidirectional continuous CFs with different coatings (uncoated and epoxy and polyester resin coatings) by applying molding for the preparation of PUR‐CF composites. Considerable reinforcement of PUR was attained even at relatively low CF content, e.g., maximum stress and Young's modulus of PUR‐CF composite at CF content 3% (m/m) were found to be 3–5 and 4–10 times higher than those of the PUR‐matrix, respectively. In addition, a linear relationship between the Young's modulus and the CF content was found as well as linear variation of maximum stress with the CF content was also observed. The adhesion of CF to the PUR‐matrix was strong in each case as concluded from the strain–stress and the scanning electron microscopy (SEM) investigations. However, the extent of reinforcement of PUR at a given CF content was found to depend greatly on the coatings of CF, and increased in the following order: epoxy resin < polyester resin < uncoated. The effect of the coating of CF on the reinforcement of PUR is also discussed. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 287–292, 2007

Synthesis and characterization of novel polyurethanes based on 1,3‐bis(hydroxymethyl) benzimidazolin‐2‐one and 1,3‐bis(hydroxymethyl) benzimidazolin‐2‐thione hard segments

AbstractNovel polyurethanes (PUs) based on 1,3‐bis(hydroxymethyl) benzimidazolin‐2‐one and 1,3‐bis(hydroxymethyl) benzimidazolin‐2‐thione as hard segments with two aromatic diisocyanates, viz., 4,4′‐diphenylmethane diisocyanate and toluene 2,4‐diisocyanate, were prepared. Polymer structures were established by Fourier transform infrared and nuclear magnetic resonance spectroscopy. Morphology of the PUs was studied by differential scanning calorimetry and thermogravimetry. All PUs contain domains of crystalline and amorphous structures as indicated by X‐ray diffraction experiments. Furthermore, polymers were insoluble in the majority of organic solvents and, hence, their solution characterization was not possible. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 2236–2244, 2005

Synthesis and characterization of novel polyurethanes containing tricyanocyclopropane ring for piezoelectric applications

1-(2',2',3'-Tricyano-3'-carbomethoxycyclopropyl)-3,4-di-2'-hydroxyethoxybenzene (4) was prepared by the reaction of bromomalononitrile with methyl 3,4-di-(2'-hydroxyethoxy)benzylidenecyanoacetate (3). Diol 4 was condensed with 3,4-toluenediisocyanate and 3,3'-dimethoxy-4,4'-biphenylenediisocynate to yield polyurethanes 5 and 6 containing multicyanocyclopropane functionalities in the pendant group. The resulting polymers 5 and 6 were soluble in common organic solvents and the inherent viscosities were in the range of 0.25–0.30 dL/g. Polyurethanes 5 and 6 showed a thermal stability up to 300°C in TGA thermograms. Solution-cast films showed T g values in the range of 100–130°C and piezoelectric coeffcients (d31) of the poled polymer films were 1.8–2.0 pC/N, which are acceptable for piezoelectric device applications.