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New thermoplastic poly(ether-urethane) elastomers were synthesized by one-step melt poly addition from poly(oxytetramethylene)diol of M¯n = 2000 g mol−1 as soft segment, 1,1′-methanediylbis(4-isocy...

New thermoplastic segmented polyurethanes were obtained by a one-step melt polyaddition using 40, 50 and 60 mol% poly(hexane-1,6-diyl carbonate) diol of \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\bar{M}_{n} = 860$$\end{document}M¯n=860 g mol−1, 1,1′-methanediylbis(4-isocyanatobenzene) and 2,2′-[sulfanediylbis(benzene-1,4-diyloxy)]diethanol, 2,2′-[oxybis(benzene-1,4-diylsulfanediyl)]diethanol or 2,2′-[sulfanediylbis(benzene-1,4-diylsulfanediyl)]diethanol as a chain extender. FTIR, atomic force microscopy, differential scanning calorimetry and thermogravimetry were used to examine the polyurethanes’ structure and thermal properties. Moreover, their Shore A/D hardness, tensile, adhesive and optical attributes were determined. They were transparent high-molar-mass materials showing good tensile strength (up to 51.9 MPa). The polyurethanes exhibited improved adhesion to copper taking into consideration that of conventional ones, and middle or high refractive index values (1.57–1.60), and both these parameters increased with an increase of the content of sulfur atoms in the polyurethane chain. The newly obtained polyurethanes can be considered as materials for numerous medical and optical appliances.

New thermoplastic poly(ether–urethane)s and poly(carbonate–urethane)s were synthesized by a one-step melt polymerization from poly(oxytetramethylene) diol (PTMO) and poly(hexane-1,6-diyl carbonate) diol (PHCD) as soft segments, 4,4′-diphenylmethane 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 as unconventional chain extenders. The effects of the kind and amount of the polymer diol and chain extender used on the structure and properties of the polymers were studied. The polymers were examined by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction analysis, atomic force microscopy, differential scanning calorimetry, thermogravimetric analysis (TGA), TGA coupled with FTIR spectroscopy, and Shore hardness and tensile testing. The obtained high-molecular-weight polymers showed elastomeric or plastic properties. Generally, the PTMO-based polymers exhibited significantly lower glass-transition temperatures (up to −48.1 vs −1.4°C), a higher degree of microphase separation, and ordering in hard-segment domains in comparison with the corresponding PHCD-based ones. Moreover, it was observed that the polymers with the PTMO soft segments showed poorer tensile strengths (up to 36.5 vs 59.6 MPa) but higher elongations at break. All of the polymers exhibited a relatively good thermal stability. Their temperatures of 1% mass loss were in the range 270–320°C. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

Thermoplastic polyurethane elastomers (TPUs) are now widely used because of their excellent properties that include high tensile and tear strength, and good abrasion, impact and chemical resistance. TPUs are multiblock copolymers with alternating sequences of hard segments composed of diisocyanates and simple diols (chain extenders) and soft segments formed by polymer diols. Commonly used hard segments for TPUs are derived from 4,4 � -diphenylmethane diisocyanate (MDI) and aliphatic diols. The aim of our research was to examine the possibility of obtaining TPUs with good tensile properties and thermal stability by using an unconventional aliphatic-aromatic chain extender, containing sulfide linkages. Three series of novel TPUs were synthesized by melt polymerization from poly(oxytetramethylene) diol, poly(e-caprolactone) diol or poly(hexane-1,6-diyl carbonate) diol of number-average molecular weight of 2000 g mol −1 as soft segments, MDI and 3,3 � [methylenebis(1,4-phenylenemethylenethio)]dipropan-1-ol as a chain extender. The structure and basic properties of the polymers were examined using Fourier transfer infrared spectroscopy, X-ray diffraction, atomic force microscopy, differential scanning calorimetry, thermogravimetric analysis, Shore hardness and tensile tests. It is possible to synthesize TPUs from the aliphatic-aromatic chain extender with good tensile properties (strength up to 42.6 MPa and elongation at break up to 750%) and thermal stability. Because the structure of the newly obtained TPUs incorporates sulfur atoms, the TPUs can exhibit improved antibacterial activity and adhesive properties. c � 2011 Society of Chemical Industry

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%.

Two series of poly(ether urethane)s and one series of poly(ester urethane)s were synthesized, con- taining, respectively, poly(oxytetramethylene) diol (PTMO) of Mn ¼ 1000 and 2000 and poly(e-caprolactone) diol of Mn ¼ 2000 as soft segments. In each series the same hard segment, i.e., 4,4 0 -(ethane-1,2-diyl)bis(benzenethiohexa- nol)/hexane-1,6-diyl diisocyanate, with different content (� 14-72 wt %) was used. The polymers were prepared by a one-step melt polymerization in the presence of dibutyl- tin dilaurate as a catalyst, at the molar ratio of NCO/ OH ¼ 1 (in the case of the polymers from PTMO of Mn ¼ 1000 also at 1.05). For all polymers structures (by FTIR and X-ray diffraction analysis) and physicochemical, ther- mal (by differential scanning calorimetry and thermogravi- metric analysis), and tensile properties as well as Shore A/D hardness were determined. The resulting polymers were thermoplastic materials with partially crystalline structures (except the polymer with the highest content of PTMO of Mn ¼ 2000). It was found that the poly(ether urethane)s showed lower crystallinity, glass-transition tem- perature (Tg), and hardness as well as better thermal stabil- ity than the poly(ester urethane)s. Poly(ether urethane)s also exhibited higher tensile strength (up to 23.5 MPa vs. 20.3 MPa) and elongation at break (up to � 1950% vs. 1200%) in comparison with the corresponding poly(ester urethane)s. Among the poly(ether urethane)s an increase in soft-segment length was accompanied by an increase in thermal stability, tensile strength, and elongation at break, as well as a decrease in Tg, crystallinity, and hardness. V C 2008 Wiley Periodicals, Inc. J Appl Polym Sci 110: 1677-1689, 2008

New thermoplastic segmented poly(thiourethane-urethane)s (SPTUUs) were prepared by a one-step melt polymerization from 20 to 80 mol % poly(tetramethylene oxide) of M n = 1000 or poly(hexamethylene carbonate) diol (PHCD) of M n = 860 as soft segments, hexamethylene diisocyanate (HDI) and bis[4-(mercaptomethyl)phenyl]methanone (BMMPM) as a new dithiol chain extender at the NCO/(OH + SH) molar ratio of 1 in the presence of dibutyltin dilaurate as a catalyst. The structures of the SPTUUs were examined by FTIR, X-ray diffraction analysis, and scanning electron microscopy. The SPTUUs were also characterized by physicochemical, thermal, and tensile properties as well as Shore A/D hardness. The SPTUUs with the PHCD soft segments showed better tensile properties than those with the PTMO soft segments. A nonsegmented polythiourethane based on BMMPM and HDI is also described.

Various new thermoplastic segmented polyurethanes were synthesized by a one-step melt polymerization from aliphatic–aromatic α,ω-diols containing sulfur in the aliphatic chain, including 4,4′-(ethane-1,2-diyl)bis(benzenethioethanol), 4,4′-(ethane-1,2-diyl)bis(benzenethiopropanol) and 4,4′-(ethane-1,2-diyl)bis(benzenethiodecanol) as chain extenders, hexane-1,6-diyl diisocyanate (HDI) or 4,4′-diphenylmethane diisocyanate (MDI) and 20–80 mol% poly(oxytetramethylene)diol (PTMO) with molecular weight of 1000 g/mol as a soft segment. The reaction was conducted at the molar ratio of NCO/OH = 1 and 1.05, and in the case of the HDI-based polyurethanes in the presence of dibutyltin dilaurate as a catalyst. The effect of the diisocyanate used on the structure and some physicochemical, thermal and mechanical properties of the segmented polyurethanes were studied. The structures of these polyurethanes were examined by FTIR and X-ray diffraction analysis. The thermal properties were investigated by differential scanning calorimetry and thermogravimetric analysis. Shore hardness and tensile properties were also determined. All the synthesized polymers showed partially crystalline structures. The MDI-based polyurethanes were products with lower crystallinity, higher glass-transition temperature (Tg) and better thermal stability in comparison with the HDI-based ones. The MDI series polymers also exhibited higher tensile strength (up to ∼36 MPa vs. ∼23 MPa) and elongation at break (up to ∼3900% vs. ∼900%), but lower hardness than the analogous HDI series polyurethanes. In both series of the polymers an increase in PTMO soft-segment content was associated with decreased crystallinity, Tg, hardness and tensile strength. An increase in PTMO content also involved an increase in elongation at break.

The new linear thiopolyester diols (PEs) containing sulfur in the main chain were prepared by melt polymerization of newly obtained diphenylmethane-4,4'-bis (methylthiopropionic acid) with excess of 1,4-butane-diol, 1,5-pentanediol, and 1,6-hexanediol. All these PEs (M n of 2000) were converted to thiopoly(ester-urethane)s (PEUs) by addition reaction with hexamethylene diisocyanate (HDI) or 4,4'-diphenylmethane diisocyanate (MDI) which was carried out in melt at a ratio of NCO/OH = 1 or 1.05. The resulting thermoplastic PEUs were elastomeric products, completely amorphous from MDI, with glass transition temperatures ranging from -22 to -8°C. Segmented PEUs (hard segment content 53-60 wt.-%) prepared by using PEs, HDI or MDI, and bis [4-(6'hydroxyhexylthio)phenyl] ether as chain extender were elastomeric materials, particularly those from MDI, with tensile strength of 9.4-12.7 MPa. All the polymers were thermally stable up to 200-270°C. The structures of the polymers were determined by Fourier transform infrared, 1 H NMR, and X-ray analysis.

The new linear thiopolyesterdiols (PEs) containing sulfur in the main chain were synthesized by melt polycondensation of newly obtained benzophenone-4,4′-bis(methylthioacetic acid) with excess of 1,4-butanediol, 1,5-pentanediol, and 1,6-hexanediol. All these PEs (Mn of 2000–2600) were converted to thiopoly(ester-urethane)s (PEUs) by polyaddition reaction with hexamethylene diisocyanate or 4,4′-diphenylmethane diisocyanate, which was carried out in melt at the ratio of NCO/OH = 1. The resulting thermoplastic PEUs were amorphous and elastomeric, with elongation at break ranging from 630 to 1200%. The polymers were characterized by Fourier transform infrared, 1H NMR, thermogravimetric analysis, differential scanning calorimetry, and in the case of PEUs, Shore A/D hardness and tensile properties. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 3977–3983, 2000

New thermoplastic nonsegmented thiopolyurethanes were synthesized from the new low-melting aliphatic-aromatic thiodiols bis[4-(2-hydroxyethyl)thiomethylphenyl]methane, bis[4-(3-hydroxypropyl)thiomethylphenyl]methane, and bis[4-(6-hydroxyhexyl)thiomethylphenyl]methane and hexamethylene diisocyanate both by melt and solution polyaddition with dibutyltin dilaurate as a catalyst. All the thiodiols were prepared with high yields by the condensation reaction of bis(4-mercaptomethylphenyl)methane with 2-chloroethanol, 3-chloro-1-propanol, or 6-chloro-1-hexanol. The hard-segment-type polyurethanes obtained were plastic materials with partially crystalline structures. Polymerization in solution produced products with higher molecular weights (ηred = 0.97–1.24 dL/g) than polymerization in melt (ηred = 0.44–1.05 dL/g). The structures of all the polyurethanes were determined with elemental analysis, Fourier transform infrared, and X-ray diffraction analysis. Thermal properties of the polymers obtained in solution were examined by differential scanning calorimetry and thermogravimetric analysis. Shore A/D hardness and tensile properties for all the polyurethanes were also determined. Of the two kinds, the polyurethanes obtained in solution possessed better tensile properties and showed yield stress (tensile strength) in a range of 27.8–30.0 MPa at an elongation of 17.4–25.1%. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 1767–1773, 2000

New thermoplastic nonsegmented thiopolyurethanes were obtained from the low-melting aliphatic-aromatic thiodiols 4,4'-bis(2-hydroxyethylthiomethyl)benzophenone (BHEB), 4,4'-bis(3-hydroxypropylthiomethyl)benzophenone (BHPB), and 4,4'-bis(6-hydroxyhexylthiomethyl)benzenophenone(BHHB) as well as hexamethylene diisocyanate (HDI), both by melt and solution polymerization with dibutyltin dilaurate as the catalyst. The effect of various solvents on molecular-weight values was examined. The polymers with the highest reduced viscosities (0.63-0.88 dL/g) were obtained when the polymerization was carried out in a solution of tetrachloroethane, N,N-dimethyl-acetamide, and N,N-dimethylacetamide or N,N-dimethylformamide for BHEB-, BHPB-, and BHHB-derived polyurethanes, respectively. These polymers with a partially crystalline structure showed glass-transition temperatures (T g ) in the range of - to 39 °C, melting temperatures (T m ) in the range of 107 to 124 °C, and thermal stabilities up to 230 to 240 °C. The BHEB-derived polyurethane is a low-elasticity material with high tensile strength (ca. 50 MPa), whereas the BHPB- and BHHB-derived polyurethanes are more elastic, showing yield stress at approximately 16 MPa. We also obtained segmented polyurethanes by using BHHB, HDI, and 20 to 80 mol % poly(oxytetramethylene) glycol (PTMG) of M n = 1000 as the soft segment. These are high-molecular thermoplastic elastomers that show a partially crystalline structure. Thermal properties were investigated by thermogravimetric analysis and differential scanning calorimetry. The increase in PTMG content decreases the definite T g and increases the solubility of the polymers. These segmented polyurethanes exhibit the definite T g (-67 to -62 °C) nearly independent of the hard-segment content up to approximately 50 wt %, indicating the existence of mainly phase-separated soft and hard segments. Shore A/D hardness and tensile properties were also determined. As the PTMG content increases, the hardness, modulus of elasticity, and tensile strength decrease, whereas elongation at break increases.

New linear polyesters containing sulfur in the main chain were obtained by melt polycondensation of diphenylmethane-4,4'-bis(methylthioacetic acid) (DBMTAA) or diphenylmethane-4,4'-bis(methythiopropionic acid) (DBMTPA) and diphenylmethane-4,4'-bis(methylthioethanol) (DBMTE) at equimolar ratio of reagents (polyesters E-A and E-P) as well as at 0.15 molar excess of diol (polyesters E-A OH and E-P OH ). The kinetics of these reactions was studied at 150, 160, and 170°C. Reaction rate constants (k 2 ) and activation parameters (ΔG ¬= , ΔH ¬= , ΔS ¬= ) from carboxyl group loss were determined using classical kinetic methods. E-A and E-P (M n = 4400, 4600) were used for synthesis of new rubber-like polyester-sulfur compositions, by heating with elemental sulfur, whereas oligoesterols E-A OH and E-P OH (M n = 2500, 2900) were converted to thermoplastic polyurethane elastomers by reaction with hexamethylene diisocyanate (HDI) or methylene bis(4-phenyl isocyanate) (MDI). The structure of the polymers was determined by elemental analysis, FT-IR and liquid or solid-state 1 H-, 13 C-NMR spectroscopy, and X-ray diffraction analysis. Thermal properties were measured by DTA, TGA, and DSC. Hardness and tensile properties of polyurethanes and polyester-sulfur compositions were also determined.

New polyester-sulfur compositions with increased tensile strength were obtained by using new thiopolyesters crosslinkable with sulfur, derived from diphenyl-methane-4,4'-di(methylthiopropionic acid) and ethanediol (E-P) or 2,2'-oxydiethanol ( ODE-P). Such characteristics as hardness, tensile, thermomechanical, as well as some electrical properties were determined. The structure of these compositions was investigated by solid-state 13 C-NMR spectroscopy.

The new linear polyesters containing sulfur in the main chain were obtained by melt polycondensation of diphenylmethane-4,4'-di methylthiopropionic acid) with ethanediol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,2-propanediol, 1,3-butanediol, and 2,2'-oxydiethanol. Low-molecular weights, low-softening temperatures and, very good solubility in organic solvents are their characteristics. The structure of all polyesters was determined by elemental analysis, FT-IR and 1 H-NMR spectroscopy, and x-ray diffraction analysis. The thermal behavior of these polymers was examined by differential thermal analysis (DTA), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). The kinetics of polyesters formation by uncatalyzed melt polycondensation was studied in a model system: diphenylmethane-4,4'-di(methylthiopropionic acid) and 1,4-butanediol or 2,2'-oxydiethanol at 150, 160, and 170°C. Reaction rate constants (k 3 ) and activation parameters (ΔG ¬= , ΔH ¬= , ΔS ¬= ) from carboxyl group loss were determined using classical kinetic methods.

We synthesized new thiodicarboxylic acids, p-tolylmethylthiomethylsuccinic acid and 1-naphthylmethylthiomethylsuccinic acid, and thiodiols, 2-(p-tolylmethylthiomethyl)-1,4-butanediol and 2-(1-naphthylmethylthiomethyl)-1,4-butanediol, by the addition of dimethyl itaconate with p-tolylmethanethiol or 1-naphthylmethanethiol, followed by hydrolysis or reduction, respectively, of the resultant dimethyl esters. These difunctional monomers were used for the synthesis of new linear polyesters and polyurethanes containing sulfur in the side chain. The polyesters were synthesized by melt polycondensation of the obtained acids with 2,2′-oxydiethanol. We found reduced viscosity, molecular weight (by GPC), and softening temperature for the reaction products. Low molecular weights, low softening temperature, and very good solubility in organic solvents are their characteristics. The polyurethanes were prepared by polyaddition diols with hexamethylene diisocyanate and tolylene diisocyanate in benzene. They were characterized by reduced viscosity and some tensile properties. The polyurethane derived from 2-(p-tolylmethylthiomethyl)-1,4-butanediol and hexamethylene diisocyanate (ηred. 1.17 dL/g) behaves like a high elasticity thermoplastic elastomer. Thermal stability of all polymers was determined by thermogravimetric analysis. The structure of the monomers and polymers were confirmed by elemental analysis and FTIR and 1H-NMR spectroscopy. © 1996 John Wiley & Sons, Inc.

New polyester–sulfur compositions with increased tensile strength were obtained by heating polyesters derived from diphenylmethane-4,4′-di(methylthioacetic acid) and ethylene or diethylene glycol with elemental sulfur. The hardness, tensile, thermomechanical, as well as some electrical properties of reaction products were determined. © 1993 John Wiley & Sons, Inc.

Several new polyesters containing sulfur in the main chain were obtained by melt polycondensation of diphenylmethane-4,4′-di(methylthioacetic acid) with ethanediol, 1,3-propane diol, 1,4-butanediol, 1,5-pentenediol, 1,6-hexanediol, 1,2-propanediol, and 2,2′-oxydiethanol. The structure of all polyesters was determined from elemental analysis and infrared (IR) spectra. Yield, reduced viscosity, molecular weight, and softening temperature for reaction products have been found. Initial decomposition and initial intensive decomposition temperature were defined from the curves of thermogravimetric analysis.

New polythioesters of better physicochemical and mechanical properties have been obtained by interfacial polycondensation of 4,4′-di(mercaptomethyl)benzophenone with terephthaloyl, isophthaloyl, and phthaloyl chlorides with the use of sodium hydroxide excess as a hydrogen chloride acceptor. According to preliminary experiments, the best yield and the highest reduced viscosity are reached when the polycondensation at a 1:l ratio of the aqueous to the organic phase is carried out at a temperature of 5–7°C with a little excess of acid chloride with addition time of 0.5–2 min in the presence of 100% excess of NaOH as hydrogen chloride acceptor. The structure of the polythioesters was determined from elemental analysis and infrared spectra. Thermal properties of all polythioesters were determined. Mechanical and electrical properties of only the most interesting polythioesters obtained from isophthaloyl chloride were determined.

Two series of new linear polyesters containing sulfur in the main chain were obtained by melt polycondensation of naphthalene-1,4-bis(methylthioacetic acid) (N-1,4-BMTAA) or naphthalene-1,5-bis(methylthioacetic acid) (N-1,5-BMTAA) with some aliphatic diols using a 0.05 molar excess of diol. Softening temperatures ranging from 55 to 130°C, reduced viscosities in the range of 0.15-0.39 dL/g, and low-molecular weights were their characteristic. The structure and thermal properties of all polyesters were examined by using elemental analysis, FT-IR and 1 H-NMR spectroscopy, X-ray diffraction analysis, differential thermal analysis (DTA), thermogravimetric analysis (TGA), and differential scanning calorymetry (DSC). The kinetics of polyester formation by uncatalyzed melt polycondensation was studied in a model system: N-1,4-BMTAA or N-1,5-BMTAA and 2,2'-oxydiethanol (ODE) at 150, 160, and 170°C. Reaction rate constants (k 3 ) and activation parameters (ΔG , ΔH , ΔS ) from carboxyl group loss were determined using classical kinetic methods. Hydroxyl-terminated polyesters derived from 1,4-butanediol, 1,5-pentanediol, and 1,6-hexanediol were used for preparation of the polyurethanes by melt polyaddition with hexamethylene diisocyanate (HDI). They were characterized by reduced viscosity, FT-IR spectroscopy, X-ray diffraction analysis, TGA, DSC, polarizing microscope observation, and hardness and tensile properties. The resulting polyurethanes behave like high-elasticity thermoplastic elastomers, except the one derived from N-1,5-BMTAA and 1,6-hexanediol-based polyester.