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Magdalena Rogulska - One of the best experts on this subject based on the ideXlab platform.
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New thermoplastic poly(carbonate-urethane)s based on diphenylethane-derivative Chain Extenders—the effect of Chain extender structure on thermal and mechanical properties
Journal of Thermal Analysis and Calorimetry, 2019Co-Authors: Magdalena RogulskaAbstract:In this study, new thermoplastic sulfur-containing poly(carbonate-urethane)s (PCURs) were synthesized via a one-step melt polyaddition from diphenylethane-derivative diols with two or ten methylene groups in the aliphatic Chain, i.e., 4,4′-(ethane-1,2-diyl)bis(benzenethioethanol) (diol E) and 4,4′-(ethane-1,2-diyl)bis(benzenethiodecanol) (diol D) as nonconventional Chain Extenders, 1,1′-methanediylbis(4-isocyanatobenzene) and 20–60 mol% poly(hexane-1,6-diyl carbonate) diol of $$\overline{M}_{\rm{n}}$$ M ¯ n = 860 g mol^−1 as a soft segment. The PCURs were studied mainly to describe their thermal and mechanical behaviors by means of DSC, TG and TG coupled with FTIR, and Shore hardness and tensile tests. Moreover, their structure and physicochemical and adhesive properties were determined. The results of the study showed that the kind of the Chain extender as well as soft-segment content had an impact on the properties of the polymers obtained. They were amorphous or semicrystalline high molar mass materials. The PCURs based on diol D exhibited lower glass transition temperatures in comparison with those based on diol E with shorter aliphatic Chain (− 1–24 °C vs. 13–55 °C). Unfortunately, the former polymers revealed somewhat poorer tensile strengths (up to 45.0 MPa vs. 51.8 MPa). Nevertheless, these values were similar to or higher than those obtained for their commercial analogs. The PCURs being diol D derivatives also showed, in general, lower hardness and the modulus of elasticity but higher elongation at break. All the PCURs exhibited a relatively good thermal stability. However, the polymers derived from diol D revealed higher temperatures of 1, 10 and 50% mass losses compared with diol E-based ones (290–298 °C vs. 285–287 °C, 325–336 °C vs. 314–323 °C, 360–381 °C vs. 348–356 °C, respectively). The newly synthesized sulfur-containing PCURs showed better adhesive properties to copper than the analogous polymer based on butane-1,4-diol as a Chain extender.
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new thermoplastic polyurethane elastomers based on aliphatic aromatic Chain Extenders with different content of sulfur atoms
Journal of Thermal Analysis and Calorimetry, 2015Co-Authors: Magdalena Rogulska, Anna Kultys, Jacek LubczakAbstract:Three series of new thermoplastic polyurethane elastomers (TPUs) were synthesized by a one-step melt polyaddition from aliphatic–aromatic Chain Extenders with different content of sulfur atoms, i.e., 2,2′-[sulfanediylbis(benzene-1,4-diyloxy)]diethanol (OSOE), 2,2′-[oxybis(benzene-1,4-diylsulfanediyl)]diethanol (SOSE) or 2,2′-[sulfanediylbis(benzene-1,4-diylsulfanediyl)]diethanol (SSSE), 1,1′-methanediylbis(4-isocyanatobenzene) (MDI) and 40, 50 or 60 mol% poly(oxytetramethylene) diol (PTMO) of \( \bar{M}_{n} \) = 1,000 g mol−1 as a soft segment. The structures of all the TPUs were examined by FTIR and atomic force microscopy. Their thermal behavior was investigated by means of differential scanning calorimetry and thermogravimetry (TG). For the selected polymers, the gaseous products evolved during the decomposition process were analyzed by TG-FTIR. Moreover, their physicochemical, tensile and adhesive properties as well as Shore A/D hardness were determined. The resulting TPUs were high-molar-mass materials with structures, which were amorphous or had a low degree of ordering. TPUs based on OSOE and SOSE showed a higher degree of microphase separation and glass-transition temperatures almost independent of soft-segment content (at ~−38 and −31 °C) than those from SSSE (from −28 to 1 °C). All TPUs were stable up to 288–297 °C, as measured by the temperature of 1 % mass loss. Their decomposition occurred in a two-step process and began within the hard segments. The main volatile products were carbon dioxide, carbonyl sulfide, aromatic compounds as well as aliphatic ethers and aldehydes. The polymers with 40 and 50 mol% PTMO content showed good tensile strength (~27–46 MPa), in most cases better than their commercial PTMO/MDI/butane-1,4-diol analogs with similar hardness values.
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the synthesis and characterization of new thermoplastic poly carbonate urethane elastomers derived from hdi and aliphatic aromatic Chain Extenders
European Polymer Journal, 2009Co-Authors: Anna Kultys, Magdalena Rogulska, Stanislaw Pikus, Krzysztof SkrzypiecAbstract:Abstract New thermoplastic poly(carbonate-urethane) elastomers (TPCUs) were prepared by a one-step melt polymerization from 20–80 mol% poly(hexane-1,6-diyl carbonate) diol of M ¯ n = 860 as a soft segment, hexane-1,6-diyl diisocyanate and 2,2′-[methylenebis(1,4-phenylenemethylenethio)]diethanol, 3,3′-[methylenebis(1,4-phenylenemethylenethio)]-dipropan-1-ol or 6,6′-[methylenebis(1,4-phenylenemethylenethio)]dihexan-1-ol (H) as new Chain Extenders at the NCO/OH molar ratio of 1 in the presence of dibutyltin dilaurate as a catalyst. The structures of the TPCUs were examined by FTIR spectroscopy, X-ray diffraction analysis, scanning electron microscopy and atomic force microscopy (AFM). The TPCUs were also characterized by physicochemical, thermal (by differential scanning calorimetry (DSC) and thermogravimetry) and tensile properties as well as Shore A/D hardness. The resulting TPCUs were colorless polymers, showing ordered structures including semicrystalline, with the highest ability to crystallize exhibited by the polymers derived from diol H. The polymers with the soft-segment content of 40–80 mol% (56.4–25.7 wt% of hard segments) exhibited a microphase separation shown by DSC and AFM. The TPCUs showed tensile strength in the range of 8.8–23.3 MPa and elongation at break in the range of 240–670%.
Jose Miguel Martinmartinez - One of the best experts on this subject based on the ideXlab platform.
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new waterborne polyurethane urea synthesized with ether carbonate copolymer and amino alcohol Chain Extenders with tailored pressure sensitive adhesion properties
Materials, 2020Co-Authors: Monica Fuensanta, Abbas Khoshnood, Francisco Rodriguezllansola, Jose Miguel MartinmartinezAbstract:New waterborne polyurethane-urea dispersions with adequate adhesion and cohesion properties have been synthesized by reacting isophorone diisocyanate, copolymer of ether and carbonate diol polyol and three amino-alcohols with different number of OH groups Chain Extenders using the prepolymer method. The waterborne polyurethane-urea dispersions were characterized by pH, particle-size distribution, and viscosity, and the polyurethane-urea films were characterized by attenuated total reflectance infrared (ATR-IR) spectroscopy, differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA), and plate-plate rheology (temperature and frequency sweeps). Polyurethane-urea pressure-sensitive adhesives (PUU PSAs) were prepared by placing the waterborne polyurethane dispersions on polyethylene terephthalate (PET) films and they were characterized at 25 °C by creep test, tack and 180° peel test. The waterborne polyurethane-urea dispersions showed mean particle sizes between 51 and 78 nm and viscosities in the range of 58-133 mPa·s. The polyurethane-urea films showed glass transition temperatures (Tgs) lower than -64 °C, and they showed a cross of the storage and loss moduli between -8 and 68 °C depending on the number of OH groups in the amino-alcohol Chain extender. Different types of PUU PSAs (removable, high shear) were obtained by changing the number of OH groups in the amino-alcohol Chain extender. The tack at 25 °C of the PUU PSAs varied between 488 and 1807 kPa and the 180° peel strength values ranged between 0.4 and 6.4 N/cm, and their holding times were between 2 min and 5 days. The new PUU PSAs made with amino-alcohol Chain extender seemed very promising for designing environmentally friendly waterborne PSAs with high tack and improved cohesion and adhesion property.
Stefan Oprea - One of the best experts on this subject based on the ideXlab platform.
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Design-properties relationships of polyurethanes elastomers depending on different Chain Extenders structures
Journal of Polymer Research, 2019Co-Authors: Stefan Oprea, Daniel Timpu, Veronica OpreaAbstract:In this study, the effect of the structure and amount of the Chain Extenders on the morphological image and physico-chemical properties of some new polyurethane elastomers has been investigated. To achieve this, three series of polyurethane elastomers based on poly(tetramethylene ether) glycol, hexamethylene diisocyanate and Chain Extenders with different structures (triethylene glycol, 3,6-dithia-1,8-octanediol, 1,6-hexanediol) were synthesized. The Chain-Extenders which introduce oxygen or sulfur atoms into the polyurethane backbone Chains (hard domains) change the behavior of the properties compared to the corresponding polyurethanes Chain-extended with aliphatic diols. The structures of the new polyurethane elastomers were examined by FTIR, X-ray diffraction analysis and by atomic force microscopy (AFM). They were also characterized for thermal and tensile properties. The polyurethanes with sulfur into their hard segment structure were found to exhibit improved thermal stability properties and equivalent mechanical properties with polyurethanes obtained with aliphatic diols. This is due to the extensive and many fold hydrogen bond network that characterizes polyurethanes with sulfur in their hard segment structure.
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Effect of resorcinol-based Chain Extenders chemical structure on the enhanced properties of polyurethane elastomers
High Performance Polymers, 2012Co-Authors: Stefan OpreaAbstract:Two series of polyurethane elastomers with resorcinol derivatives in the polymer backbone were synthesized by Chain extending isocyanate end-capped prepolymers with resorcinol, 2,4-dihydroxybenzaldehyde or 1-(2,4-dihydroxyphenyl)-hexanone-(1). Chain Extenders are differentiated from each other by the structure of the side Chain attached to the resorcinol rings. Isocyanate-terminated prepolymers were obtained from poly(1,4-butylene adipate) diol and 4,4′-diphenylmethane diisocyanate. These polyurethane elastomers were characterized using Fourier transform infrared spectroscopy, thermo-gravimetric analysis, differential scanning calorimetry, and mechanical measurements. The effects of the chemical structure of resorcinol-derivative Chain Extenders on the properties of polyurethane elastomers were investigated. A significant increase in maximum stress–strain properties and in thermal stability was observed for the samples with free carbonyl in the side Chain of the resorcinol ring. All the polymers showed 5%...
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The effect of Chain Extenders structure on properties of new polyurethane elastomers
Polymer Bulletin, 2010Co-Authors: Stefan OpreaAbstract:Two series of polyurethane elastomers were synthesized to investigate what effect does the incorporation of various new Chain Extenders have on the mechanical and thermal properties of polyurethane elastomers. The polyurethane soft segments were based on poly(ε-caprolactone) polyol. The hard segment was based on 1,6-hexamethylene diisocyanate in combination with 2,5-dimethyl-3-hexine-2,5-diol (DHD), hexaethylene glycol, glycerin, or castor oil. The results showed that the degradation rate and mechanical properties of the final products can be controlled through the structure of diol Chain Extenders or/and hard segment cross-linking present in the polyurethane elastomers. The DHD-based polyurethane displayed a relatively low glass transition temperature of −57 °C and a tensile strength of 11–14 MPa and elongation at break of 600–700%. These kinds of materials have potential application in many domains.
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the effect of Chain Extenders structure on properties of new polyurethane elastomers
Polymer Bulletin, 2010Co-Authors: Stefan OpreaAbstract:Two series of polyurethane elastomers were synthesized to investigate what effect does the incorporation of various new Chain Extenders have on the mechanical and thermal properties of polyurethane elastomers. The polyurethane soft segments were based on poly(e-caprolactone) polyol. The hard segment was based on 1,6-hexamethylene diisocyanate in combination with 2,5-dimethyl-3-hexine-2,5-diol (DHD), hexaethylene glycol, glycerin, or castor oil. The results showed that the degradation rate and mechanical properties of the final products can be controlled through the structure of diol Chain Extenders or/and hard segment cross-linking present in the polyurethane elastomers. The DHD-based polyurethane displayed a relatively low glass transition temperature of −57 °C and a tensile strength of 11–14 MPa and elongation at break of 600–700%. These kinds of materials have potential application in many domains.
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Chain Extender and Diisocyanate Amount Effects on the Thermal, Mechanical and Wettability Properties of Some Polyurethane Elastomers
E-polymers, 2008Co-Authors: Stelian Vlad, Stefan OpreaAbstract:AbstractThe aim of this study was to investigate the effect of Chain extender and diisocyanate amount on the thermal, mechanical and wettability properties of some polyurethanes. The Chain extender nature caused the increase of the thermal stability due to the higher stability of the double and triple bonds respectively in contrast to simple bonds. Tg of the polyurethanes based on PCL/MDI decreased when the unsaturated grade from Chain Extenders increased. The double and triple bonds content from polyurethane structure was responsible for this behavior. The hard segment contents and the Chain Extenders nature also influenced the wettability. The results showed that the thermal, mechanical and wettability properties of the final products might be controlled by fine control of the amount of the MDI and the nature of the Chain Extenders
Andrew P Dove - One of the best experts on this subject based on the ideXlab platform.
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application of modified amino acid derived diols as Chain Extenders in the synthesis of novel thermoplastic polyester urethane elastomers
ACS Sustainable Chemistry & Engineering, 2017Co-Authors: Ruairi P Brannigan, Anthony J Walder, Andrew P DoveAbstract:Owing to their robust processability and mechanical dexterity, thermoplastic polyurethanes (TPUs) have been utilized in a wide variety of applications from commodity to more niche biomedical applications. Despite this, the focus on deriving monomers from sustainable resources has been relatively low; however, bioderived diisocyanates, diamine/diol Chain Extenders, and polyester-based polyols have all been studied. Herein we report the application of biorenewable diol Chain Extenders derived from amino acids using an organocatalyzed process in bulk. To determine the effect of extender Chain length on the properties of the resultant materials, TPEUs were synthesized using diol Extenders derived from amino acids, 1-(1,3-dihydroxypropan-2-yl)-3-ethylurea (C3u), 1-(1,4-dihydroxybutan-2-yl)-4-ethylurea (C4u), and 1-(1,5-dihydroxypentan-2-yl)-5-ethylurea (C5u). When poly(e-caprolactone) (PCL) and 1-isocyanato-4-[(4-isocyanatocyclohexyl) methyl]cyclohexane (H12MDI) were used as the polyol and diisocyanate, respec...
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Application of Modified Amino Acid-Derived Diols as Chain Extenders in the Synthesis of Novel Thermoplastic Polyester–Urethane Elastomers
2017Co-Authors: Ruairi P Brannigan, Anthony Walder, Andrew P DoveAbstract:Owing to their robust processability and mechanical dexterity, thermoplastic polyurethanes (TPUs) have been utilized in a wide variety of applications from commodity to more niche biomedical applications. Despite this, the focus on deriving monomers from sustainable resources has been relatively low; however, bioderived diisocyanates, diamine/diol Chain Extenders, and polyester-based polyols have all been studied. Herein we report the application of biorenewable diol Chain Extenders derived from amino acids using an organocatalyzed process in bulk. To determine the effect of extender Chain length on the properties of the resultant materials, TPEUs were synthesized using diol Extenders derived from amino acids, 1-(1,3-dihydroxypropan-2-yl)-3-ethylurea (C3u), 1-(1,4-dihydroxybutan-2-yl)-4-ethylurea (C4u), and 1-(1,5-dihydroxypentan-2-yl)-5-ethylurea (C5u). When poly(ε-caprolactone) (PCL) and 1-isocyanato-4-[(4-isocyanatocyclohexyl) methyl]cyclohexane (H12MDI) were used as the polyol and diisocyanate, respectively, TPEUs were synthesized yielding materials with a predetermined percentage “hard segment” (%HS) and molecular weight. It was established through the selection of extender Chain length and by controlling the %HS, that both the thermal and mechanical properties of the TPEUs could be controlled. Furthermore, the extender Chain length was found to affect both the hydrophilicity and hydrolytic degradation profile of the resultant materials
Li Xing Dai - One of the best experts on this subject based on the ideXlab platform.
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Tuning Chain extender structure to prepare high-performance thermoplastic polyurethane elastomers
RSC Advances, 2018Co-Authors: Jianjun Wang, Shi Yu Zhang, Jun Sun, Chuanxiang Qin, Li Xing DaiAbstract:Ester-containing ferrocenyl diols are introduced as Chain Extenders to tune the polyurethane superstructure to optimize thermo-stability and elasticity simultaneously.