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Corresponding Poly (corresponding + poly)
Selected AbstractsCloud-Point Pressure Curves of Ethene/Poly[ethylene- co -((meth)acrylic acid)] MixturesMACROMOLECULAR CHEMISTRY AND PHYSICS, Issue 4 2003Michael Buback Abstract Ethene-methacrylic acid (MAA) and ethene-acrylic acid (AA) copolymers of narrow polydispersity and high chemical homogeneity have been synthesized at acid unit copolymer contents up to 9 mol-% within a continuously operated stirred tank reactor at overall monomer conversions of about 2%. Cloud-point pressures (CPPs) of mixtures of 3 wt.-% copolymer in ethene (E) have been measured in an optical high-pressure cell at pressures and temperatures up to 3,000 bar and 260,°C, respectively. The CPP weakly increases with acid copolymer content up to about 3.5 mol-%. Toward higher acid contents, the CPP is strongly enhanced, in particular at the lower edge of the experimental temperature range at around 200,°C. This increase in CPP is more pronounced for the AA than for the MAA systems. The data suggest that hydrogen-bonding interactions are operative in the pressurized E/poly(E- co -(M)AA) mixtures at temperatures of 260,°C and perhaps even above. E-AA and E-MAA copolymers with acid contents of about 5.6 mol-% have also been completely methyl-esterified to yield the associated methyl esters. The CPPs of the resulting E-methyl acrylate and E-methyl methacrylate copolymers in mixtures with E are significantly below the CPPs of the corresponding E/poly(E- co -(M)AA) systems. Cloud-point pressure vs temperature curves for several E/poly(E- co -methacrylic acid) systems. The subscripts denote copolymer content in mol-%. A cloud-point pressure curve for E/polyethylene (PE) is included for comparison. [source] Studies on thermoplastic polyurethanes based on new diphenylethane-derivative diols.JOURNAL OF APPLIED POLYMER SCIENCE, Issue 3 2008Abstract Two series of poly(ether urethane)s and one series of poly(ester urethane)s were synthesized, containing, respectively, poly(oxytetramethylene) diol (PTMO) of Mn = 1000 and 2000 and poly(,-caprolactone) diol of Mn = 2000 as soft segments. In each series the same hard segment, i.e., 4,4,-(ethane-1,2-diyl)bis(benzenethiohexanol)/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 dibutyltin dilaurate as a catalyst, at the molar ratio of NCO/OH = 1 (in the case of the polymers from PTMO of Mn = 1000 also at 1.05). For all polymers structures (by FTIR and X-ray diffraction analysis) and physicochemical, thermal (by differential scanning calorimetry and thermogravimetric 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 = 2000). It was found that the poly(ether urethane)s showed lower crystallinity, glass-transition temperature (Tg), and hardness as well as better thermal stability 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. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 [source] Synthesis of a norbornene monomer having cyclic carbonate moiety based on CO2 fixation and its transition metal-catalyzed polymerizationsJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 17 2010Atsushi Sudo Abstract A norbornene monomer bearing cyclic carbonate moiety (NB-CC) was successfully synthesized from the corresponding precursor having epoxy moiety by its reaction with carbon dioxide under atmospheric pressure, which was efficiently catalyzed by lithium bromide. NB-CC underwent the ring-opening metathesis polymerization (ROMP) catalyzed by a ruthenium carbene complex to give the corresponding poly(norbornene), of which side chain inherited the cyclic carbonate moiety from the monomer without any deterioration. The same ROMP system was applicable to the copolymerization of NB-CC and 5-butyl-2-norbornene (BNB), which afforded the corresponding copolymer with a composition ratio same as a feed ratio. In addition, by using a catalytic system consisted of palladium (II) acetate/tricyclohexylphosphine/triphenylcarbenium tetrakis(pentafluorophenyl)borate, the copolymerization of NB-CC and BNC proceeded successfully in a vinyl addition polymerization mode to give the corresponding poly(norbornene) having CC moiety in the side chain. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 3896,3902, 2010 [source] Aliphatic poly(ester-carbonate)s bearing amino groups and its RGD peptide graftingJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 21 2008Xiuli Hu Abstract This article deals with (1) synthesis of novel cyclic carbonate monomer (2-oxo [1,3]dioxan-5-yl)carbamic acid benzyl ester (CAB) containing protected amino groups; (2) ring-opening copolymerization of the cyclic monomer with L -lactide (LA) to provide novel degradable poly(ester-carbonate)s with functional groups; (3) removal of the protective benzyloxycarbonyl (Cbz) groups by catalytic hydrogenation to afford the corresponding poly(ester- co -carbonate)s with free amino groups; (4) grafting of oligopeptide Gly-Arg-Gly-Asp-Ser-Tyr (GRGDSY, abbreviated as RGD) onto the copolymer pendant amino groups in the presence of 1,1,-carbonyldiimidazole (CDI). The structures of P(LA- co -CA/RGD) and its precursor were confirmed by 1H NMR analysis. Cell experiments showed that P(LA- co -CA/RGD) had improved adhesion and proliferation behavior. Therefore, the novel RGD-grafted block copolymer is promising for cell or tissue engineering applications. © Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 7022,7032, 2008 [source] A variety of poly(m -benzamide)s with low polydispersities from inductive effect-assisted chain-growth polycondensationJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 17 2006Tomoyuki Ohishi Abstract Chain-growth polycondensation of 3-(alkylamino)benzoic acid alkyl esters 1 was investigated for obtaining poly(m -benzamide)s with defined molecular weights and low polydispersities. Polymerization conditions were first studied to find that ethyl 3-(octylamino)benzoate (1b) polymerized in a chain polymerization manner in the presence of lithium 1,1,1,3,3,3-hexamethyldisilazide (LiHMDS) as a base and phenyl 4-methylbenzoate (2b) as an initiator in THF at 0 °C. The molecular weight of the polymer was controlled by the feed ratio of monomer to initiator. The polymerization of 1c,i with a variety of N -alkyl groups was then carried out under the established conditions to yield well-defined poly(m -benzamide)s, which showed higher solubility than those of the corresponding poly(p -benzamide)s. Furthermore, the 4-octyloxybenzyl group on the amide nitrogen in poly1i was removed by treatment with trifluoroacetic acid (TFA) to give N -unsubstituted poly(m -benzamide) (poly1j) with a low polydispersity, which is soluble in DMAc and DMSO, contrary to the para-substituted counterpart. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 4990,5003, 2006 [source] Studies on the modification of poly(,-bromoalkyl-1-glycidylether)s with 4,-methoxybiphenyl-4-oxy mesogenic groupsJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 23 2005J. M. Montornés Abstract A series of poly[,-(4,-methoxy-biphenyl-4-oxy)alkyl-1-glycidylether]s were synthesized by chemically modifying the corresponding poly(,-bromoalkyl-1-glycidylether)s with the sodium salt of 4-hydroxy-4,-methoxybiphenyl. New high-molecular-weight side-chain liquid-crystalline polymers were obtained with excellent yields and almost quantitative degrees of modification. They were all insoluble in THF and other common solvents. Characterization by 13C NMR confirmed that all the polymers had the expected structure. The liquid crystalline behavior of the polymers was analyzed by DSC and polarized optical microscopy, and mesophase assignments were confirmed by X-ray diffraction studies. Polymers that had alkyl spacers with n = 2 and 4 were smectic C, those that had spacers with n = 6 and 8 were nematic cybotactic, and those that had longer spacers (n = 10 and 12) were smectic C again. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 5998,6006, 2005 [source] | ||||||||||