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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.

New segmented poly(thiourethane-urethane)s (PTU-Us) (with hard-segment content of 30–60 mass%) were synthesized by a one-step melt polymerization from poly(oxytetramethylene) diol of $$ \overline{M}_{n} $$ = 1,000 g mol−1 or $$ \overline{M}_{n} $$ = 2,000 g mol−1 or poly(hexamethylene carbonate) diol of $$ \overline{M}_{n} $$ = 860 g mol−1 as soft segments, 1,1′-methanediylbis(4-isocyanatocyclohexane) (Desmodur W ®) and (methylenedi-1,4-phenylene)dimethanethiol as a chain extender. The PTU-Us were examined by FTIR, GPC, XRD, DSC, TG, Shore hardness, and tensile testing. Moreover, refractive index, transparency, adhesive properties, and resistance to bacteria and fungi were determined for selected polymers. The obtained high-molar-mass amorphous polymers showed elastomeric or plastic properties. Their T gs were in the range from −70 to 58 °C. The PTU-Us with the polycarbonate soft segments demonstrated a better segmental miscibility (higher T gs), transparency as well as generally higher tensile strength and hardness than those with the polyether soft segments. All the synthesized PTU-Us showed a relatively good thermal stability. The temperature of 1 % mass loss of all PTU-Us was in the range of 236–255 °C. The introduction of thiourethane linkages to polyurethane chain caused increase of the adhesive strength on copper–polymer junction and refractive index values. From the microbial studies, it was found that the obtained polymers had delayed the growth of Gram-positive bacteria.

New thermoplastic polyurethane elastomers (TPUs) were synthesized by a one-step melt polyaddition from poly(oxytetramethylene) diol of M¯n = 2000 g/mol as the soft segment, 1,1’-methanediylbis(4-isocyanatocyclohexane) (HMDI, Desmodur W®), and 2,2’-[methanediylbis(benzene-4,1-diylmethanediylsulfanediyl)]diethanol (diol E) or 6,6’-[methanediylbis(benzene-4,1-diylmethanediylsulfanediyl)]dihexane-1-ol (diol H) 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 spectroscopy, gel permeation chromatography, thermogravimetric analysis, differential scanning calorimetry, Shore hardness and tensile testing. Both the adhesive and optical properties were determinated for a selected polymer. The obtained TPUs were amorphous, colorless, high-molar-mass materials. It was observed that the polymers with the diol E showed higher hardness and tensile strengths but smaller elongations at break than diol H-based ones. All of the polymers exhibited a relatively good thermal stability. Their temperatures of 5% mass loss were in the range 312-338°C.

Two series of new thermoplastic poly(thiourethane-urethane) elastomers (EPTURs), with different hard-segment content (40–60 wt%), were synthesized by a one-step melt polymerization from poly(oxytetramethylene) diol (PTMO) of \( \overline{M}_{\text{n}} \) = 1,000 g mol−1 or poly(hexamethylene carbonate) diol (PHCD) of \( \overline{M}_{\text{n}} \) = 860 g mol−1 as a soft segment, hexane-1,6-diyl diisocyanate and (methylenedi-1,4-phenylene)dimethanethiol as a chain extender at the NCO/(OH + SH) molar ratio of 1. The structures of all the EPTURs were examined by Fourier transform infrared spectroscopy (FTIR), atomic force microscopy and X-ray diffraction analysis. Their thermal behavior was investigated by means of differential scanning calorimetry and thermogravimetric analysis (TG). For the chosen polymers the gaseous products evolved during the decomposition process were analyzed by TG-FTIR. Moreover, physicochemical, adhesive and tensile properties as well as Shore A/D hardness were determined. The resulting high-molecular-mass EPTURs were stable up to 254–262 °C, as measured by the temperature of 1 % mass loss. They decomposed in three or four stages. The main decomposition products were carbonyl sulfide, isocyanate, carbon dioxide, aromatic hydrocarbons as well as aliphatic ethers and aldehydes (in PTMO series) and alcohols (in PHCD series). All the polymers showed partially crystalline structures, associated with crystallization of thiourethane hard segments. Their melting temperatures were in the range of 184–186 °C. The PTMO series EPTURs exhibited better low-temperature properties (glass-transition temperature in the range of −64 to −44 vs. −26 to −22 °C), but poorer tensile strengths (20–28 vs. 37–43 MPa). These EPTURs showed improved adhesive properties in comparison with their polyurethane analogs.

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

Four aliphatic-aromatic diols with ether linkages [4, 4′-Bis(2-hydroxyethoxy)benzophenone, 4, 4′-Bis(3-hydroxypropoxy)benzophenone, 4, 4′-Bis(6-hydroxyhexyloxy)benzophenone, 4, 4′-Bis(11-hydroxyundecyloxy)benzophenone] and two aliphatic-aromatic diols with sulfur linkages [4, 4′-Bis[(2-hydroxyethyl)thio]benzophenone, 4, 4′-Bis[(3-hydroxypropyl)thio]benzophenone] have been characterized by X-ray powder diffraction. These diols can be used for synthesis of thermoplastic nonsegmented polyurethanes. Experimental 2θ peaks positions, relative peak intensities, values of d, and Miller indices as well as unit-cell parameters are presented.

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.

Five new aliphatic-aromatic thiodiols: 1,2-bis[4-(2′-hydroxyethylthio)phenyl]ethane (C18H22O2S2), 1,2-bis[4-(3′-hydroxypropylthio)phenyl]ethane (C20H26O2S2), 1,2-bis[4-(6′-hydroxyhexylthio)phenyl]ethane (C26H38O2S2), 1,2-bis[4-(10′-hydroxydecylthio)phenyl]ethane (C34H54O2S2), 1,2-bis[4-(11′-hydroxyundecylthio)phenyl]ethane (C36H58O2S2) have been characterized by X-ray powder diffraction. These thiodiols can be used for synthesis of thermoplastic nonsegmented polyurethanes. Experimental 2θ peaks positions, relative peak intensities, values of d and Miller indices as well as unit cell parameters are reported.

The new linear hydroxyl-terminated thiopolyesters (PEs) containing thioether linkages in the main chain were prepared by melt polymerization of newly obtained diphenylmethane-4,4'-bis(methylthioacetic acid) with excess of 1,4-butanediol, 1,5-pentanediol (PD), and 1,6-hexanediol. All these PEs ( {\bar M}_n of ∼1900-2500) 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 the ratio of NCO/OH=1.05. The PEUs obtained were elastomeric products, completely amorphous from MDI or with a little tendency to crystallize from HDI. Their characteristics were m red =0.65-0.93 dL/g, glass transition temperatures ranging from m 12.7 to m 0.9°C, tensile strength of 0.4 m 2.3 MPa, elongation at break of 650-2000%, and thermal stabilities of up to 230-260°C. Segmented PEUs (hard segment content ∼50 wt.%) prepared by using the PD-based PE, HDI or MDI, and bis[4-(6-hydroxyhexylthio)phenyl] eth...

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.

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 high-molar-mass thermoplastic poly(carbonate–urethane)s (PCURs) were synthesized from nonconventional sulfur-containing chain extenders, i.e., 2,2′-[sulfanediylbis(benzene-1,4-diyloxy)]diethanol (diol SE) and 2,2′-[methanediylbis(benzene-1,4-diylmethanediylsulfanediyl)]diethanol (diol ME), 1,1′-methanediylbis(4-isocyanatobenzene) and 30, 45 and 60 mol% aliphatic polycarbonate diol of M n = 2000 g mol−1 (Desmophen® C2200, Bayer) via a one-step melt polyaddition. The PCURs were investigated by FTIR, UV–Vis, atomic force microscopy, X-ray diffraction analysis, differential scanning calorimetry, thermogravimetry (TG) and TG-FTIR. Moreover, their Shore A/D hardness, tensile, adhesive and optical properties were determined. The obtained PCURs were transparent or opaque elastomers, possessing amorphous or partially crystalline structures. The polymers based on diol ME showed lower glass transition temperatures (−9 to (−8) vs. −7 to 20 °C) and better microphase separation. All the PCURs exhibited a relatively good thermal stability. Their temperature of 1 % mass loss was within the range of 284–292 °C with somewhat higher values shown by those obtained from diol ME. The PCURs decomposed in two (from diol ME) or three (from diol SE) stages, and for both types of polymers, the main decomposition occurred at the first stage. All the PCURs based on diol SE exhibited higher tensile strength (33.5–41.9 vs. 27.0–31.5 MPa), but smaller elongation at break (300–400 vs. 450–550 %) than polymers derived from diol ME. Somewhat better adhesive properties and a slightly higher refractive index were found for polymer based on diol ME with two sulfur atoms.

New thermoplastic polyurethane elastomers (TPUs) were obtained by a one-step melt polyaddition from 30, 45 and 60 mol% aliphatic polycarbonate diol of M n = 2000 g mol−1 (Desmophen® C2200, Bayer), 1,1′-methanediylbis(4-isocyanatocyclohexane) (HMDI) or 1,6-diisocyanatohexane (HDI) and 2,2′-[sulfanediylbis(benzene-1,4-diyloxy)]diethanol (acting as a chain extender). The TPUs were examined by FTIR, UV–Vis, atomic force microscopy, X-ray diffraction analysis, differential scanning calorimetry, thermogravimetry (TG) and TG–FTIR. Moreover, their Shore A/D hardness, tensile, adhesive and optical properties were determined. The obtained TPUs were transparent or opaque high molar mass materials, showing amorphous or partially crystalline structures. The HDI-based TPUs exhibited lower glass-transition temperatures than those based on HMDI (from −35 to −31 °C vs. from −20 to 1 °C) as well as a higher degree of microphase separation. The TPUs were stable up to 262–272 °C, taking into account the temperature of 1 % mass loss, with somewhat higher values shown by those from HDI. They decomposed in two stages. The main volatile products of the hard-segment decomposition were carbon dioxide, water and carbonyl sulfide, while aliphatic ethers, aldehydes and unsaturated alcohols, as well as carbon dioxide, originated from the soft-segment decomposition. The synthesized TPUs, with hardness in the range of 80–90°Sh A, possessed a good tensile strength (33.0–38.7 MPa), similar to that of the commercial biodurable medical grade TPU ChronoFlex® AL 80A (37.9 MPa), prepared from aliphatic polycarbonate diol, HMDI and butane-1,4-diol.