Synthesis and characterization of biodegradable poly(ε-caprolactone)/poly(γ-benzyl <Emphasis Type="SmallCaps">l</Emphasis>-glutamate) block copolymer

A biodegradable poly(ε-caprolactone)/poly(γ-benzyl l-glutamate) (PCL-b-PBLG) block copolymer was synthesized by ring-opening polymerization of N-carboxy-γ-benzyl l-glutamate anhydride (BLG-NCA) with amine-terminated poly(ε-caprolactone) (PCL-NH₂) as a macroinitiator. The PCL-NH₂ was prepared by deprotection of a PCL-CH₂CH₂NHBoc, which was obtained by ring-opening polymerization of ε-caprolactone (ε-CL) initiated by Boc-aminoethanol (HOCH₂CH₂NHBoc) using stannous octanoate as catalyst under microwave irradiation. The structures of the block copolymers were determined by IR, ¹H NMR, and GPC measurements. The results prove that BLG-NCA can be initiated by PCL-NH₂ to produce PCL-b-PBLG block copolymers.     

Synthesis and Properties of Alkyl <Emphasis Type="Italic">β</Emphasis>-<Emphasis Type="SmallCaps">d</Emphasis>-Galactopyranoside

A series of alkyl β-d-galactopyranosides were prepared by the trichloroacetimidate method with d-galactose and alcohols with different chain lengths as raw materials. Their solubility, surface tension, emulsification, foaming, wettability, thermotropic liquid crystalline properties, and thermal stability were investigated. Alkyl β-d-galactopyranosides are soluble in water and ethanol, and the solubility decreases with increasing alkyl chain length. Decyl β-d-galactopyranoside was insoluble in water, but soluble in ethanol. Dissolution of alkyl β-d-galactopyranoside in water is an endothermic process with dissolution enthalpies greater than zero. Nonyl β-d-galactopyranoside had an excellent emulsifying property, better foaming ability and the best foam stability. The CMC values of alkyl β-d-galactopyranosides decrease with increasing of alkyl chain length. Alkyl β-d-galactopyranosides are thermally stable up to 270 °C. Alkyl β-d-galactopyranosides show the distinctive optical texture of a thermotropic liquid crystal smectic A type phase. Decyl β-d-galactopyranoside showed the strongest wettability.     

pH- and thermo-sensitive semi-IPN hydrogels composed of chitosan, <Emphasis Type="Italic">N</Emphasis>-isopropylacrylamide,and poly(ethylene glycol)-<Emphasis Type="Italic">co</Emphasis>-poly(ε-caprolactone) macromer for drug delivery

In this study, semi-IPN chitosan/poly(N-isopropylacrylamide) (PNIPAAm) hydrogels have been prepared via in situ UV-photo-crosslinking of N-isopropylacrylamide monomer using poly(ethylene glycol)-co-poly(ε-caprolactone) (PEG-co-PCL) macromer as a crosslinker in the presence of chitosan. Swelling properties of the resultant hydrogels were studied by investigating pH- and temperature dependence of equilibrium swelling ratio and oscillatory swelling–deswelling kinetics. It was found that semi-IPN hydrogels responded to both temperature and pH changes, and such stimuli-responsiveness was rapidly reversible. The rheological measurements demonstrated that the incorporation of chitosan greatly improved the mechanical strength of the hydrogels prepared. The release profiles of bovine serum albumin (BSA) from the hydrogels were also evaluated. The results showed that the release rate of BSA was higher in pH 2.0 buffer solution than in pH 7.4 buffer solution at 37 °C. Such double-sensitive hydrogels have the potential to use as smart carriers for drug delivery systems.     

Syntheses and optical properties of <Emphasis Type="Italic">α</Emphasis>- and <Emphasis Type="Italic">β</Emphasis>-cyano-poly(<Emphasis Type="Italic">p</Emphasis>-phenylene vinylene) derivatives

Two light emitting molecules with the cyano group at different positions on the vinylene i.e., 2,5-bis(2-thienyl-1-cyanovinyl)-1-(2_-ethylhexyloxy)-4-methoxybenzene (-TPT) and 2,5-bis(2-thienyl-2-cyanovinyl)-1-(2-ethylhexyloxy)-4-methoxybenzene (-TPT), and corresponding polymers, i.e., poly[2,5-bis(2-thienyl-1-cyanovinyl)-1-(2-ethylhexyloxy)-4-methoxybenzene] (denoted as P1) and poly[2,5-bis(2-ethienyl-2-cyanovinyl)-1-(2-ethylhexyloxy)-4-methoxybenzene] (denoted as P2) were synthesized. -TPT and -TPT, respectively, were blended into two host polymers, poly(methyl methacrylate (PMMA) and poly(9-vinylcarbazole) (PVK), to study the optical properties of the dopants in different host polymer matrices. Although -TPT and -TPT have the same backbone structure, their optical properties are much different. The PL emission maximum ( _max) of -TPT was found blue-shifted, compared with that of -TPT, while the PL intensity of -TPT was stronger than that of -TPT. Concentration effect in the optical properties was found, 1 wt% of -TPT in PVK had the maximum fluorescent emission.The PL maximum peak wavelengths for polymer films (P1 and P2) were found red-shifted; while their PL intensities were weaker when compared with those of blends.     

Dual stimuli-responsive supramolecular polymeric nanoparticles based on poly(<Emphasis Type="Italic">α</Emphasis>-cyclodextrin) and acetal-modified <Emphasis Type="Italic">β</Emphasis>-cyclodextrin-azobenzene

To aim at pH environment in tumor tissue and light-controlled drug release, UV and pH dual-responsive supramolecular polymeric nanoparticles mediated by host-guest interactions of poly(α-cyclodextrin) and acetal-modified β-cyclodextrin-azobenzene were developed in this work. The host molecule was poly(α-cyclodextrin) and the guest molecule was composed of acetal-modified β-cyclodextrin with one azobenzene linked. The inclusion of α-cyclodextrin and azobenzene leaded to amphiphilic supramolecular polymer, which further self-assembled to form supramolecular polymeric nanoparticles in aqueous medium. UV and pH responsiveness of supramolecular polymeric nanoparticles attributed to azobenzene and acetal, respectively. Supramolecular polymeric nanoparticles based on poly(α-cyclodextrin) and acetal-modified β-cyclodextrin-azobenzene with the average diameter of sub-100 nm were controllable to release the drugs regulated by pH and UV.     

Synthesis of novel polymer brushes of poly(acrylonitrile-<Emphasis Type="Italic">g</Emphasis>-<Emphasis Type="Italic">N,N</Emphasis>ʹ-dimethylaminoethyl methacrylate) by nitrile modification

Functional polymer brushes of poly(acrylonitrile-g-N,N?-dimethylaminoethyl methacrylate) were efficiently synthesized by a novel approach of combining Cu(0)-mediated controlled/“living” radical polymerization and nitrile click chemistry. The poly(acrylonitrile-g-N,N?-dimethylaminoethyl methacrylate) as a promising material exhibited excellent hydrophile–lipohile balance in the process of self-assembly and could autonomously develop the orderly structure micelle in N,N?-dimethylformamide/water mixture solvent for the potential application of a new drug delivery carrier. In the process of self-assembly, polyacrylonitrile acted as a backbone of the functional polymer brushes due to its hydrophobic feature and poly(N,N?-dimethylaminoethyl methacrylate) as the branch of functional polymer brushes due to its hydrophilic characteristic, which both were prepared by Cu(0)-mediated controlled/“living” radical polymerization with ethyl-bromoisobutyrate as initiator. Poly(N,N?-dimethylaminoethyl methacrylate) containing azide end group was synthesized by substitution reaction of poly(N,N?-dimethylaminoethyl methacrylate) containing bromine end groups with sodium azide in N,N?-dimethylformamide. The click reaction between the nitrile of polyacrylonitrile and the azide group of poly(N,N?-dimethylaminoethyl methacrylate) was carried out under ammonium chloride as catalyst in N,N?-dimethylformamide. The polymer was further confirmed by GPC, FTIR, ¹H NMR and TGA. Meanwhile, the micelles with different morphologies were observed by TEM, and the particle diameter distribution of self-assembled micelle from the PAN-g-PDMAEMA brushes was determined by DLS.     

Synthesis and self-assembly of a new amphiphilic thermosensitive poly(N-vinylcaprolactam)/poly(ε-caprolactone) block copolymer

New amphiphilic thermosensitive poly(N-vinylcaprolactam)/poly(ε-caprolactone) (PNVCL-b-PCL) block copolymers were synthesized by ring-opening polymerization of ε-caprolactone with hydroxy-terminated poly(N-vinylcaprolactam) (PNVCL-OH) as a macroinitiator. The structures of the polymers were confirmed by IR, ¹H NMR and GPC. The critical micelle concentrations of copolymer in aqueous solution measured by the fluorescence probe technique reduced with the increasing of the proportion of hydrophobic parts, so did the diameter and distribution of the micelles determined by dynamic light scattering. The shape observed by transmission electron microscopy (TEM) demonstrated that the micelles are spherical. On the other hand, the UV–vis measurement showed that polymers exhibit a reproducible temperature-responsive behavior with a lower critical solution temperature (LCST). The LCST of PNVCL-OH can be adjusted by controlling the molecular weights, and that of copolymers can be adjusted by controlling the compositions and the concentration. Variable temperature TEM measurements demonstrated that LCST transition was the result of transition of individual micelles to larger aggregates.     

Dynamic-mechanical behavior of polyethylenes and ethene/<Emphasis Type="Italic">α</Emphasis>-olefin-copolymers: Part II. <Emphasis Type="Italic">α</Emphasis>- and <Emphasis Type="Italic">β</Emphasis>-relaxation

Several ethylene homopolymers and ethene/ α-olefin-copolymers with crystallinities ranging between 85 and 12% were characterized by dynamic-mechanical measurements. The occurring relaxations were correlated to the crystallinity of the polymeric materials and to morphology. The α-relaxation, being attributed to interlamellar shear, was found to be around 60 °C with activation energies of about 120 kJ/mol in samples with more than 42% crystallinity. The β-transition shows a much greater variety among the different samples characterized. Its relaxation temperatures vary between −40 and 10 °C with activation energies between 200 and 400 kJ/mol. The α- and β-relaxation of several quenched samples with crystallinities between 63 and 42% were found to overlap, thus producing bimodal maxima and different activation energies from the Arrhenius plots. A separation of these overlapping relaxations was only possible by measuring the relaxations over a frequency range of more than three orders of magnitude.     

Synthesis and characterization of amphiphilic triblock-graft PEG-(<Emphasis Type="Italic">b</Emphasis>-PαN<Subscript>3</Subscript>CL-<Emphasis Type="Italic">g</Emphasis>-Alkyne)<Subscript>2</Subscript> degradable copolymers

The study proposes a straightforward strategy for synthesizing novel, amphiphilic triblock-graft PEG-(b-PαN₃CL-g-Alkyne)₂ degradable copolymers. First, this investigation performs copolymerization of α-chloro-ε-caprolactone (αClCL) using α,ω-dihydroxyl-terminated macroinitiator poly(ethylene glycol) (PEG) and stannous octoate as the catalyst. In a second step, the current work converts pendent chlorides into azides by reacting with sodium azide. Finally, various kinds of terminal alkynes react with pendent azides by copper-catalyzed Huisgen’s 1,3-dipolar cycloaddition, thus a “click” reaction. These copolymers are characterized by differential scanning calorimetry (DSC), ¹H NMR, IR and gel permeation chromatography. The resulting triblock-graft copolymers exhibit lower crystallinity and melting temperature with respect to the original PEG. The triblock-graft copolymers form micelles in the aqueous phase with critical micelle concentrations (CMCs) in the range of 1.58–8.62 mg L⁻¹, depending on polymer composition. The ¹H NMR spectrum of micelles in D₂O demonstrate only the PEG signal and thus confirm the PCL-g-Alkyne blocks constitute the micelle core, while the central PEG block constitutes the micelle shell. The hydrophilic segment lengths influence the micelle shape. The mean hydrodynamic diameters of micelles from DLS range from 90–200 nm. The work describes drug entrapment efficiency and drug loading content of micelles depending on the composition of triblock-graft polymers.      

Vaccenic acid (<Emphasis Type="Italic">t</Emphasis>11–18∶1) is converted to <Emphasis Type="Italic">c</Emphasis>9,<Emphasis Type="Italic">t</Emphasis>11-CLA in MCF-7 and SW480 cancer cells

The aims of this study were to determine whether vaccenic acid (VA; t11–18∶1) is converted to c9,t11-CLA in human mammary (MCF-7) and colon (SW480) cancer cell lines and whether VA influences cell viability and other CLA-bioresponsive markers. When cells were incubated in the presence of VA at concentrations of 5 to 20 μg/mL, both VA and c9,t11-CLA increased in cellular lipids in a dose-dependent manner. After 4 d of incubation of SW480 and MCF-7 cells with VA (20 μg/mL), c9,t11-CLA increased from undetectable levels to 8.57 and 12.14 g/100 g FAME in cellular lipids, respectively. VA supplementation for 4 d at 5, 10, and 15 μg/mL had no effect on cell growth, whereas 20 μg/mL significantly (P<0.05) reduced cell growth in both cell lines. VA (20 μg/mL) treatment induced DNA fragmentation and significantly (P<0.05) depeleted cytosolic GSH levels in the SW480 cell line after 4 d of incubation, suggesting that apoptosis was the mode of cell death induced by VA. Both VA and c9,t11-CLA reduced (P<0.05) total ras expression in SW480 cells. ¹⁴C-Arachidonic acid uptake into the MG fraction was significantly increased (P<0.05) in both cell lines while uptake into the phospholipid fraction decreased in response to VA. VA treatment significantly (P<0.05) increased 8-epi-prostaglandin F_2α in both cell lines. The data indicate that growth suppression and cellular responses of both cells lines are likely mediated by VA desaturation to c9,t11-CLA via Δ⁹-desaturase.     

Regiospecific Analyses of Triacylglycerols of Hoki (<Emphasis Type="Italic">Macruronus novaezelandiae</Emphasis>) and Greenshell™ Mussel (<Emphasis Type="Italic">Perna canaliculus</Emphasis>)

The lipid profiles of the two most important New Zealand marine oil sources were investigated, with particular attention to the regioisomeric compositions of triacylglycerides (TAG), using ¹³C-nuclear magnetic resonance analysis. Oils from hoki (Macruronus novaezelandiae) and Greenshell™ mussel (Perna canaliculus) (GSM) were analyzed for their lipid content, lipid class and fatty acid profile. The regiospecific distribution of long chain (C ≥ 20) polyunsaturated fatty acids (LC-PUFA) between the sn-1,3 and sn-2 glycerol positions was calculated from ¹³C responses in the carbonyl region in the triacylglycerol fraction. Rendered hoki oil (RHO) produced from the viscera and filleting discards, had a similar lipid profile to that of hoki liver oil (HLO) confirming that the liver is the major source of oil in RHO. The regioisomeric distribution of fatty acids showed differences between the two oil sources. Docosahexaenoic acid (DHA) had a regioisomeric distributional preference to the sn-2 position in TAG from all the oils (59.2% HLO, 54.3% RHO and 63.4% GSM). Eicosapentaenoic acid (EPA) had a more even distribution along the triacylglycerol backbone in hoki TAG (29.1% HLO, 33.6% RHO) while there was a slight sn-2 positional preference in the GSM TAG (37.6%). This regioisomeric information is vital to distinguish LC-PUFA-rich marine oils from other marine sources for authentication purposes.     

Enhanced <Emphasis Type="Italic">β</Emphasis>-carotene production by <Emphasis Type="Italic">Rhodotorula glutinis</Emphasis> using high hydrostatic pressure

High hydrostatic pressure (HHP) technology was used for improving the ability of β-carotene biosynthesis of Rhodotorula glutinis R68. After the treatments of five repeated cycles at 300 MPa for 15 min, the barotolerant mutant PR68 was obtained. After 72 h of culture, the biomass of mutant PR68 was 21.6 g/L, decreased by 8.5% compared to the parent strain R68, but its β-carotene production reached 19.4 mg/L, increased by 52.8% compared to the parent strain R68. The result of restriction fragment length polymorphism analysis suggested that mutant strain PR68 was likely to change in nucleic acid level, and thus enhanced β-carotene production in this strain was a result of gene mutation induced by HHP treatment. HHP technology seems a promising approach for improving industrial microbes.     

Cellulose–<Emphasis Type="Italic">co</Emphasis>-polyacrylonitrile blends: Properties of combined solutions in <Emphasis Type="Italic">N</Emphasis>-metylmorpholine-<Emphasis Type="Italic">N</Emphasis>-oxide and the formation and thermolysis of composite fibers

Combined solutions of cellulose and an acrylonitrile-based copolymer in N-methylmorpholine-N-oxide have been prepared for the first time, new composite fibers have been formed, and the properties of the solutions and fibers under standard conditions and during thermal treatment have been studied. On the basis of studying the phase state and morphological peculiarities of combined cellulose solutions with polyacrylonitrile additives, it has been shown that the completed solutions make emulsions in the entire range of investigated concentrations. The rheological behavior of combined solutions changes with temperature. With the use of IR spectroscopy methods, it has been found that the addition of polyacrylonitrile to cellulose results in the association of nitrile groups with hydroxyl groups of cellulose, which favors the cyclization of CN groups during heating and the appearance of polyconjugated bonds in polyacrylonitrile chains. Thermal transformations of cellulose and polyacrylonitrile in the course of mixed-fiber carbonization have been studied via DSC and TGA. It has been shown that polyacrylonitrile inhibits the dehydration processes in cellulose and reduces the intensity of the peak due to the first stage of the structural rearrangement, i.e., acts as a “catalyst” of pyrolysis.     

Preparation and properties of <Emphasis Type="Italic">α</Emphasis>-phenylcinnamylideneacetylated poly(2-hydroxyethyl methacrylate)

A photosensitive polymer, -phenylcinnamylideneacetylated poly(2-hydroxyethyl methacrylate) (poly(HEMA)), was synthesized and characterized. Light irradiation upon the photosensitive poly(HEMA) film induced gel formation via dimerization between the pendent -phenylcinnamylideneacetylates of the polymer. The gel content of the crosslinked polymer increased with increasing irradiation time and reached 60% when irradiated for 30 minutes. Correspondingly, the water content decreased from 27% to 18% with irradiation time increasing from 0 to 30 minutes. The solute permeability of the -phenylcinnamylideneacetylated poly(HEMA) without irradiation is about the same as that of the poly(HEMA) film. The crosslinked -phenylcinnamylideneacetylated poly(HEMA) film prepared by light irradiation had much lower permeability as compared with the non-crosslinked film. More specifically, the photocrosslinked film had the permeability of 5.37 × 10^–7 cm/s, 1.32 × 10^–7 cm/s and 0.53 × 10^–7 cm/s for p-nitrophenol, tryptophan and flurbiprofen, respectively. This photosensitive -phenylcinnamylideneacetylated poly(HEMA) provides a new base material for fabricating poly(HEMA) hydrogel.     

A novel ∈-lysine acylase from <Emphasis Type="Italic">Streptomyces mobaraensis</Emphasis> for synthesis of <Emphasis Type="Italic">N∈</Emphasis>-acyl-<Emphasis Type="SmallCaps">l</Emphasis>-lysines

A novel ∈-lysine acylase (N ₆-acyl-l-lysine amidohydrolase; EC 3.5.1.17) was isolated from Streptomyces mobaraensis and purified to homogeneity by SDS-PAGE from the culture broth. The purified enzyme was monomeric, with a molecular mass of approximately 60 kDa. The enzyme was inactivated by the presence of 1,10-phenanthroline and activated in the presence of Co²⁺ and Zn²⁺. The enzyme showed a pH optimum of 8.0 and was stable at temperatures of up to 50°C for 1 h at pH 8.0. The enzyme specifically catalyzed the hydrolysis of the amide bond of various N∈-acyl-l-lysines. Furthermore, the enzyme efficiently catalyzed the synthesis of N∈-acyl-l-lysines with fatty and aromatic acyl groups in an aqueous buffer. In the syntheses of N∈-decanoyl-l-lysine, N∈-lauroyl-l-lysine, and N∈-myristoyl-l-lysine, the product precipitated and the yield was 90% or higher using 10 mM FA and 0.5 M l-lysine as the substrate.     

Solid Solution (AlN)<Subscript><Emphasis Type="Italic">x</Emphasis></Subscript>(SiC)<Subscript>1–<Emphasis Type="Italic">x</Emphasis></Subscript> (<Emphasis Type="Italic">x</Emphasis> ≈ 0.7) by SHS under High Pressure of Nitrogen Gas

Solid solution (AlN) _x (SiC)_1–x (x = 0.7) was prepared from Al–SiC mixtures by SHS under high pressure of nitrogen gas (50, 70 MPa) and characterized by XRD and SEM. Combustion product was found to have a wurtzite 2H structure with lattice parameters a = 3.10889 ± 0.00022 Å and c = 5.00741 ± 0.00080 Å.     

(11<Emphasis Type="Italic">Z</Emphasis>,13<Emphasis Type="Italic">E</Emphasis>)-Hexadecadien-1-yl Acetate: Sex Pheromone of the Grass Webworm <Emphasis Type="Italic">Herpetogramma licarsisalis</Emphasis>—Identification,Synthesis, and Field Bioassays

The grass webworm Herpetogramma licarsisalis (Lepidoptera: Crambidae), which has recently established in pasture in Northland, New Zealand, is an important pest of many tropical and subtropical grasses. Two pheromone components, (Z)-11-hexadecen-1-yl acetate (Z11–16:Ac) and (11Z,13E)-hexadecadien-1-yl acetate (Z11,E13–16:Ac), were identified in pheromone gland extracts of female moths by gas chromatography (GC), GC-electroantennographic detection, and GC-mass spectrometry in conjunction with microchemical tests (dimethyldisulfide and 4-methyl-1,2,4-triazoline-3,5-dione derivatizations). Z11,E13–16:Ac and its geometric isomer (11E,13Z)-hexadecadien-1-yl acetate (E11,Z13–16:Ac) were synthesized via stereoselective Wittig reactions, and the identity of the diene present in the pheromone glands was confirmed to be Z11,E13–16:Ac. Field bioassays at Indooroopilly in Brisbane, Australia, established that Z11,E13–16:Ac was necessary and sufficient for attraction of male grass webworm moths and that the corresponding alcohol, (11Z,13E)-hexadecadien-1-ol (Z11,E13–16:OH), had a strong inhibitory effect on trap catches at the ratios tested. When mixed with Z11,E13–16:Ac in various ratios, Z11–16:Ac had no effect on the attractiveness of lures. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Cadmium acetate as a ring opening polymerization catalyst for the polymerization of <Emphasis Type="Italic">rac</Emphasis>-lactide, <Emphasis Type="Italic">ε</Emphasis>-caprolactone and as a precatalyst for the polymerization of ethylene

In the present study, we have discussed the bulk ring opening polymerization (ROP) of rac-lactide (rac-LA) and ε-caprolactone (ε-CL) using Cd(OAc)₂. Cd(OAc)₂ appeared to be a good catalyst for the polymerization of rac-LA and ε-CL yielding high molecular weight (M _n) polymers with narrow molecular weight distributions (MWDs). The catalytic activity of the system can be increased markedly upon using catalytic amount of BnOH as external alcoholic initiator. There is a first order dependence of the rate constant with respect to monomer concentrations as understood from the kinetic studies. The rate was found to be faster in the presence of BnOH. The polymerization process was controlled. The polymerization proceeded via the coordination-insertion mechanism without BnOH as well as activated monomer mechanism in the presence of BnOH. In the absence of BnOH, the acetyl group initiated the polymerization as understood from the ¹H NMR and MALDI-TOF analysis. The benzyloxy group initiated the polymerization in the presence of BnOH. Moderate activity towards the polymerization of ethylene was observed using MAO as alkyl aluminum activator. The polymerization parameters towards the polymerization of ethylene were widely investigated.

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Graphical abstract The catalytic activity of Cd(OAc)₂ towards the ROP of rac-LA and ε-CL and precatalyst for the polymerization of ethylene were investigated.

     

Synthesis and characterization of biodegradable thermoplastic elastomers derived from <Emphasis Type="Italic">N</Emphasis>′,<Emphasis Type="Italic">N</Emphasis>-bis (2-carboxyethyl)-pyromellitimide,poly(butylene succinate) and polyethylene glycol

Biodegradable poly(ether-imide-ester) elastomers were synthesized from succinic acid, 1,4-butanediol, polyethylene glycol 1000 and N′,N-bis(2-carboxyethyl)- pyromellitimide which was derived from pyromellitic dianhydride and glycine. The chemical structures, crystallinities, thermal stabilities, mechanical properties, hydrophilicities and biodegradabilities of these elastomers were investigated. The hard segments of the linear aliphatic poly (ether-ester) exhibited monoclinic chain packing. Increasing the amount of aromatic bisimide moieties in the poly (ether-ester) reduced the crystallinity of the material and improved the thermal stability and tensile strength of the elastomers. In addition, introducing a suitable amount of aromatic bisimide moieties into the poly(ether-ester) backbones endowed the elastomers with improved biodegradability but too many aromatic bisimide groups reduced the biodegradability of the elastomers.

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