Dehydroabietyl polyethylene glycol glycidyl ether-grafted hydroxyethyl cellulose(HEC)polymer surfactant(DA(EO)5GE-g-HEC)was prepared using ring-opening polymerization with biobased rosin and hydroxyethyl cellulose as ...Dehydroabietyl polyethylene glycol glycidyl ether-grafted hydroxyethyl cellulose(HEC)polymer surfactant(DA(EO)5GE-g-HEC)was prepared using ring-opening polymerization with biobased rosin and hydroxyethyl cellulose as feedstocks.Dehydroabietyl polyethylene glycol glycidyl ether(DA(EO)5GE)was formed by condensation of dehydroabietyl alcohol polyoxyethylene ether(Rosin derivative:DA(EO)5H)and epichlorohydrin.The grafting degree of DA(EO)5GE-g-HEC was manipulated by adjusting the mass ratio of HEC and DA(EO)5GE and confirmed by EA.According to the formula,when m(HEC)/m(DA(EO)2GE)was 1:1~1:5,the grafting rate of DA(EO)5GE in DA(EO)5GE-g-HEC varied from 34.43%to 38.33%.The surface activity and foam properties of DA(EO)5GE-g-HEC aqueous solution were studied.The results showed that with the increase in grafting rate,the critical micellar concentration(CMC)in aqueous solution changed from 1.28 to 0.96 g/L.The results of the thermogravimetric analysis showed that the temperature range of the main stage of mass loss of DA(EO)5GE-g-HEC was 310°C~410°C,and the thermal decomposition processes of the samples with five mass ratios were similar.An oil in water emulsion was prepared by choosing cyclohexane as the oil phase and DA(EO)5GE-g-HEC as the emulsifier.The effect of DA(EO)5GE-g-HEC mass fraction on emulsion particle size and stability was analyzed.The results suggested that when the oil-water ratio was 8:2 with 0.4%emulsifier,the emulsion droplets were the smallest in terms of particle size and were the most stable.The rheological test results showed that the apparent viscosity decreased with the increase in shear rate and showed a typical elastic gel phenomenon.展开更多
A series of homo and copolymers of styrene (ST) and 2-hydroxyethyl methacrylate (HEMA) in three different media (bulk, tetrahydrofuran, and benzene) have been investigated by free radical polymerization method. The sa...A series of homo and copolymers of styrene (ST) and 2-hydroxyethyl methacrylate (HEMA) in three different media (bulk, tetrahydrofuran, and benzene) have been investigated by free radical polymerization method. The samples obtained from the synthesis were characterized by Fourier Transform-Infrared spectroscopy (FT-IR), proton nuclear magnetic resonance spectroscopy (<sup>1</sup>H NMR), atomic force microscopy (AFM), and differential scanning calorimetry (DSC). The results show that the synthesis of the polymers is more feasible under neat conditions rather than solvent directed reaction. Moreover, the DSC data shows that the polystyrene obtained is amorphous in nature and therefore displayed only a glass transition signal rather than crystallization and melting peaks. In addition, this study indicates that homolopolymerization of styrene via free radical polymerization tends to be preferable in less polar solvents like THF than in non-polar solvents like benzene. Benzene might destabilize the formation of the reactive radicals leading to the formation of the products. In summary, the homolpolymerization of styrene is more feasible than the homopolymerization 2-hydroxyethyl methacrylate under the experimental setup used. Styrene is more reactive than 2-hydroxyethyl methacrylate than free radical polymerization reaction due in part of the generation of the benzylic radical intermediate which is more stable leading to the formation of products than alkyl radical which are less stable. Furthermore, polymerization of styrene under neat conditions is preferable in solvent-assisted environments. The choice of solvent for the synthesis of these polymers is crucial and therefore the selection of solvent that leads to the formation of a more stable reaction intermediate is more favorable. It is worth noting that the structure of the proposed copolymer consists of a highly polar and hydrophilic monomer, 2-hydroxyethyl methacrylate and a highly non-polar and hydrophobic monomer, styrene. These functionalities constitute an amphiphilic copolymer with diverse characteristics. A plausible explanation underlying our observations is that the reaction conditions employed in the synthesis of these copolymers might not be the right route required under free radical polymerization.展开更多
Waterborne coatings often delaminate and settle during long-term storage,requiring the addition of thickeners.The effects of nanofibrillated cellulose(NFC)and the commonly used thickener,hydroxyethyl cellulose(HEC),on...Waterborne coatings often delaminate and settle during long-term storage,requiring the addition of thickeners.The effects of nanofibrillated cellulose(NFC)and the commonly used thickener,hydroxyethyl cellulose(HEC),on the storage stability of waterborne coatings were compared in this study.The morphology of NFC was characterized using infrared spectroscopy(FT-IR)and scanning electron microscopy(SEM).The rotational viscosity and rheological properties of the waterborne coatings with NFC and HEC were tested.Stationary settling experiments were also conducted at different temperatures to compare the difference of NFC and HEC on improving the storage stability of the waterborne coatings.The results showed that the waterborne coating with NFC exhibited pseudoplastic fluid characteristics;a small addition of NFC can achieve the same improvement effect on the storage stability of waterborne coatings as HEC.Further,the improvement effect of NFC was not affected by temperature.The waterborne coating with NFC still exhibited good storage stability at high temperatures,which was significantly superior to that of HEC.Therefore,NFC is a feasible agent for improving the prolonged storage stability and warming-induced delamination of waterborne coatings.展开更多
The reaction of 3-nitro-4-chlorobenzenesulfinic acid and ethylene oxide to obtain 2-nitro-4-(β-hydroxyethylsulfonyl)chlorobenzene had been studied. Except hydroxyethylation on the sulfur atom of 3-nitro-4-chloroben...The reaction of 3-nitro-4-chlorobenzenesulfinic acid and ethylene oxide to obtain 2-nitro-4-(β-hydroxyethylsulfonyl)chlorobenzene had been studied. Except hydroxyethylation on the sulfur atom of 3-nitro-4-chlorobenzenesulfinic acid to form the target product, 2-nitro-4-(β- hydroxyethylsulfonyl)chlorobenzene, there presented three kinds of side reactions: 1. Condensation and elimination of HCI to form biphenyl sulfone derivatives; 2. Addition to give bisulfonyl ethane derivative via vinyl sulfone; and 3. Hydroxylethylation on O-atom to produce hydroxylethylsulfinate due to the tautomerism of sulfinic acid.展开更多
Two kinds of UV curable polyurethane acrylate oligomers (PUPA and PUCA) were synthesized via the addition reaction between isophorone diisocyanate (IPDI) and polyethylene glycol monoacrylate (PEA6) or polycaprol...Two kinds of UV curable polyurethane acrylate oligomers (PUPA and PUCA) were synthesized via the addition reaction between isophorone diisocyanate (IPDI) and polyethylene glycol monoacrylate (PEA6) or polycaprolactone modified hydroxyethyl acrylate (PCLA2). The structures of PUPA and PUCA were characterized by Fourier transform infrared spectroscopy (FT-IR), IH nuclear magnetic resonance (^H NMR), gel permeation chromatography (GPC) and differential scanning calorimeter (DSC), and the thermal stability and dynamic mechanical thermal properties of their cured films were measured by thermogravimetric analysis (TGA) and dynamic mechanical analysis (DMA), respectively. The viscosity of the oligomers and mechanical properties of the cured films were also studied. The results show that both oligomers have narrow molecular weight distribution. The viscosity of PUPA is 2.310 Pa.s at 25 ℃, while that of PUCA is: up to 3.980 Pa-s. The UV cured PUPA and PUCA films have homogeneous phase structure, and the PUCA film shows higher glass transition temperature and storage modulus. Furthermore, the PUCA film possesses better mechanical properties than PUPA, while the latter shows better alkali resistance.展开更多
Hydroxyethyl chitosan (HE-chitosan) is a water-soluble derivative of chitosan with many apparent biological properties. For example, it is non-toxic and rapidly biodegradable. Moreover, HE-chitosan has advantages in...Hydroxyethyl chitosan (HE-chitosan) is a water-soluble derivative of chitosan with many apparent biological properties. For example, it is non-toxic and rapidly biodegradable. Moreover, HE-chitosan has advantages in water-solubility, moisture retention and gelling property due to its hydroxyethyl group. However, the biocompatibility and biodegradability of this multifimctional de- rivative have rarely been documented although they are critical for its application in biomedical and clinical treatments. The purpose of this work was to evaluate the biosafety of HE-chitosan, and draw important clues for its diverse applications. HE-chitosan was synthesized and characterized its chemical structure with FTIR. Its molecular weight (Mw) was determined by gel permeation chro- matography (GPC), and its deacetylation degree (DD) was investigated through potentiometric analysis. The cytotoxicity of HE-chitosan on mouse fibroblast cell L929 was tested. The biocompatibility and biodegradability of HE-chitosan in rat and rabbit were evaluated. The FTIR results indicated that the hydroxyethyl groups were linked to C6 of chitosan. The GPC analysis confirmed that its Mw was about 90.01 kDa. It was also demonstrated that HE-chitosan had excellent biocompatibility and biodegradability in vivo and had no cytotoxicity on L929. These findings indicated that HE-chitosan can potentially be applied as a biomaterial in tissue engineering, drug delivery, and other biomedical fields.展开更多
An efficient protocol for the synthesis of N^6-(2-Hydroxyethyl)adenosine and its analogues through nucleophilic substitution was developed. All the reactions were completed in 10 rain under microwave irradiation. Us...An efficient protocol for the synthesis of N^6-(2-Hydroxyethyl)adenosine and its analogues through nucleophilic substitution was developed. All the reactions were completed in 10 rain under microwave irradiation. Using water as solvent makes our method eco-friendly and easy to handle with.展开更多
A new bicadmium(??) complex [Cd2L](ClO4)2?1.25H2O (C28H35Cd2Cl4N6O13.25) was synthesized and characterized by X-ray diffraction and ES mass spectral analyses. It crystallizes in the triclinic system, space gro...A new bicadmium(??) complex [Cd2L](ClO4)2?1.25H2O (C28H35Cd2Cl4N6O13.25) was synthesized and characterized by X-ray diffraction and ES mass spectral analyses. It crystallizes in the triclinic system, space group P1 with a = 15.630(3), b = 15.990(3), c = 16.330(3) ?, α = 89.90(3), β = 68.87(3), γ = 87.94(3)o, V = 3804.1(13) ?3, Mr = 1034.22, Z = 4, F(000) = 2060, Dc = 1.806 g/cm3, T = 293(2) K, μ = 1.468 mm-1 and λ = 0.71073 ?. The structure was refined to R = 0.0779 and wR = 0.1960 for 7034 observed reflections with I > 2σ(I).展开更多
The thermal decomposition process was studied by the TG–DTA analyzer. The results show that the decomposition process of sodium hydroxyethyl sulfonate consisted of three stages: the mass loss for the first, the secon...The thermal decomposition process was studied by the TG–DTA analyzer. The results show that the decomposition process of sodium hydroxyethyl sulfonate consisted of three stages: the mass loss for the first, the second and third stages may be about the groups of CH_3CH_2OH, CH_3CHO and SO_2 volatilized, respectively. The decomposition residuum of three stages was analyzed by FT-IR, and the results of FT-IR agreed with the decomposition process predicted by theoretical weight loss. The specific heat capacity of sodium hydroxyethyl sulfonate was determined by differential scanning calorimetry(DSC). The melting temperature and melting enthalpy were obtained to be 465.41 K and 25.69 kJ·mol^(-1), respectively. The molar specific heat capacity of sodium hydroxyethyl sulfonate was determinated from 310.15 K to 365.15 K and expressed as a function of temperature.展开更多
BACKGROUND Accidental dural puncture(ADP)and subsequent post-dural puncture headache(PDPH)remain common complications of epidural procedures for obstetric anesthesia and analgesia.No clear consensus exists on the best...BACKGROUND Accidental dural puncture(ADP)and subsequent post-dural puncture headache(PDPH)remain common complications of epidural procedures for obstetric anesthesia and analgesia.No clear consensus exists on the best way to prevent PDPH after ADP.CASE SUMMARY We report our findings in twenty parturients who underwent an incorporated strategy of epidural analgesia followed by epidural hydroxyethyl starch(HES)to prevent PDPH after ADP with a 16-gauge Tuohy needle during epidural procedures.ADP with a 16-gauge Tuohy needle occurred in nine parturients undergoing a cesarean section(CS)and in eleven parturients receiving labor analgesia.An epidural catheter was re-sited at the same or adjacent intervertebral space in all patients.After CS,the epidural catheter was used for postoperative pain relief over a 48-h period.After delivery in eleven cases,epidural infusion was maintained for 24 h.Thereafter,15 mL of 6%HES 130/0.4 was administered via the epidural catheter immediately prior to catheter removal.None of the parturients developed PDPH or neurologic deficits over a follow-up period of at least two months to up to one year postpartum.CONCLUSION An incorporated strategy of epidural analgesia followed by epidural hydroxyethyl starch may have great efficacy in preventing PDPH after ADP.展开更多
The thermal behavior of thermotropic hydroxyethyl cellulose acetate (HECA)/polyethylene (PE) blends has been studied by DSC. It is found that the blends of HECA and PE are immiscible but the crystallization of PE is a...The thermal behavior of thermotropic hydroxyethyl cellulose acetate (HECA)/polyethylene (PE) blends has been studied by DSC. It is found that the blends of HECA and PE are immiscible but the crystallization of PE is affected by HECA chains in the blends with more than 50% HECA, which results in the subordinate crystallization of PE and the formation of imperfect structures in the PE crystals. The imperfection of PE crystals in the blends can be eliminated after annealing at 393K.展开更多
Environmentally friendly biocomposites were prepared by blending wheat gluten(WG)as a matrix, hydroxyethyl cellulose(HEC)as a filler,and glycerol as a plasticizer,followed by thermo-molding of the mixture at 120...Environmentally friendly biocomposites were prepared by blending wheat gluten(WG)as a matrix, hydroxyethyl cellulose(HEC)as a filler,and glycerol as a plasticizer,followed by thermo-molding of the mixture at 120°C for crosslinking the matrix.Moisture absorption,tensile properties,dynamic mechanical analysis,and dynamic rheology were evaluated in relation to the glycerol content.Tensile strength and modulus drop dramatically with increasing glycerol content,which is accompanied by significant depression in the glass transition temperature and improvement in the extensibility of the biocomposites.展开更多
The position and quantity of the hydroxyethyl groups in hydroxyethyl starch (HES) were studied by GC/MS and NMR. Quantitative characterization was carried out based on the results of both methods.
The title compound, 2-O-(2-hydroxyethyl)-D-glucose (CsH1607, Mr= 224.21), has been synthesized and its structure was characterized by using NMR spectrum and X-ray single-crystal diffraction. This molecule crystall...The title compound, 2-O-(2-hydroxyethyl)-D-glucose (CsH1607, Mr= 224.21), has been synthesized and its structure was characterized by using NMR spectrum and X-ray single-crystal diffraction. This molecule crystallizes in the monoclinic system, space group P21, with a = 8.399(17), b = 6.620(14), c = 9.81(2) A, β = 115.110(17)°, V= 493.7(18) A3, Z = 2, Dc = 1.508 mg/m3,/1 = 0.13 mm-1, F(O00) = 240, the final R = 0.0464 and wR = 0. l 15 for 152 ] observed reflections (1 〉 2a(I)). X-ray crystal structure analysis revealed that the conformation of the pyranosyl ring existed in a slightly distorted act chair conformation (Cremer-Pople puckering parameters of Q = 0.573(4) A, 0 = 6.7(3)0 and = -5.2(2)°). The molecule exists as a monomer in the solid state, whose conformation is stabilized via multiple inter- and intramolecular hydrogen bonds.展开更多
Nineteen L-N-2-hydroxyethylamino acids and L-N,N-bis(2-hydroxyethyl)amino acids were prepared from the reaction of chlorohydrin with L-alanine,L-valine,L-leucine,L-isoleucine,L- phenylalanine,L-serine,L-thrcunine,L-gl...Nineteen L-N-2-hydroxyethylamino acids and L-N,N-bis(2-hydroxyethyl)amino acids were prepared from the reaction of chlorohydrin with L-alanine,L-valine,L-leucine,L-isoleucine,L- phenylalanine,L-serine,L-thrcunine,L-glutamic acid,L-aspartic acid and glycine.L-N,N,N',N'-tetra (2-hydroxyethyl)cystine was prepared by the reaction of L-cystine with chlorohydrin.展开更多
A new blend of poly(2-hydroxyethyl methacrylate) (PHEMA) with poly (ethylene glycol) (PEG) was prepared. The results from solid-state NMR indicate that the PHEMA/PEG(88:12, w/w) blend is miscible on a molecular level.
Purpose: The primary aim of this study was to investigate volume effect and safety of up to 50 mL/kg BW 6% hydroxyethyl starch (HES) 130/0.4 in adult and pediatric patients undergoing major elective surgery. The need ...Purpose: The primary aim of this study was to investigate volume effect and safety of up to 50 mL/kg BW 6% hydroxyethyl starch (HES) 130/0.4 in adult and pediatric patients undergoing major elective surgery. The need to infuse human albumin may be reduced or avoided in Japan if these large doses 6% HES 130/0.4 can be infused. Methods: The study was an uncontrolled, open-labeled, multi-center trial. Fifteen adult and 5 pediatric patients undergoing major elective surgery received 6% HES 130/0.4 (Voluven®) with a maximum dose of 50 mL/kg from the start of surgery until 2 hours after the end of surgery according to a treatment algorithm. The primary efficacy endpoint was the volume effect of 6% HES 130/0.4 determined by the volume of saved albumin during the investigational period and the time course of hemodynamic stability in adult and pediatric patients. Safety parameters were fluid balance, hemodynamic and laboratory parameters ECG, local and systemic tolerance and adverse events. Results: Adult patients received a mean of 32.0 mL/kg of 6% HES 130/0.4. For 12 out of 15 adult patients an average amount of 1033.8 mL (18.6 mL/kg) albumin could be saved. The other 3 adult patients did not receive more than 1000 mL of HES 130/0.4. All pediatric patients received approximately 50 mL/kg of HES 130/0.4;for these patients an average amount of 39.9 mL/kg body weight albumin could be saved. The majority of adult patients, and all pediatric patients were hemodynamically stable at all 3 time points. The observed changes of the assessed laboratory parameters including hematological and coagulation parameters or in any other safety parameter determined did not reveal any safety concern related to the administration of 6% HES 130/0.4 up to doses of 50 mL/kg body weight. Conclusion: The study results indicate that 6% HES 130/0.4 has a reliable volume effect, could contribute to significant human albumin savings and was safe and well tolerated up to a maximum dose of 50 mL/kg body weight in adult and pediatric patients undergoing major elective surgery.展开更多
The copolymerization of 2-hydroxyethyl acrylate (HEA, M//1) and methyl methacrylate (MMA, M//2) in cyclohexanone was studied. The multiple experiments of solution copolymerization with low conversion were carried out...The copolymerization of 2-hydroxyethyl acrylate (HEA, M//1) and methyl methacrylate (MMA, M//2) in cyclohexanone was studied. The multiple experiments of solution copolymerization with low conversion were carried out at two sensitive composition feed points at 60, 80, 100, 120 and 140 degree C, respectively. The composition of the copolymers was analyzed by **1H-NMR. The reactivity ratios which were estimated by the Error-in-Variable Method (EVM) of Mayo-Lewis equation were found to be r//1 equals 0.328, r//2 equals 1.781 for 60 degree C; 0.375, 1.709 for 80 degree C; 0.406, 1.654 for 100 degree C; 0.439, 1.540 for 120 degree C and 0.455, 1.400 for 140 degree C, and the 95% joint confidence intervals of the reactivity ratios were also determined. According to r//1 and r//2, Arrhenius relations and the activity energy difference between the homo- and cross-propagation were calculated. (Author abstract) 12 Refs.展开更多
A simple,eco-friendly.sensitive and economic flow injection spectrofluorimetric method was developed for the determination of O-(β-hydroxyethyl)rutosidcs.The procedure was based on the use of an anionic surfactant ...A simple,eco-friendly.sensitive and economic flow injection spectrofluorimetric method was developed for the determination of O-(β-hydroxyethyl)rutosidcs.The procedure was based on the use of an anionic surfactant such as sodium dodecyl sulfate to provide an appreciable O-(β-hydroxyethyl)rutosides fluorescence enhancement,increasing considerably the sensitivity of detection.All the variables affecting the fluorescence intensity were studied and optimized.The flow rate was 5 mL/min with detection at 450 nm(after excitation at 346 nm).A linear correlation between drug amount and peak area was established for 0-(β-hydroxyethyl)rulosides in the range of 0.01-200 μg/mL with a detection limit of0.001 μg/mL(s/n = 3).Validation processes were performed by recovering studies with satisfactory results.The new methodology can be employed for the routine analysis of 0-(P-hydroxyethyl)rutosides in bulks as well as in commercial formulations.展开更多
Background: In June 2013, the FDA issued a Black Box Warning on synthetic colloids resulting from data indicating an increased risk of mortality, renal injury, and excess bleeding incidence in septic patients admitted...Background: In June 2013, the FDA issued a Black Box Warning on synthetic colloids resulting from data indicating an increased risk of mortality, renal injury, and excess bleeding incidence in septic patients admitted to the Intensive Care Unit (ICU), and patients undergoing coronary artery bypass graft (CABG) surgery. The purpose of this study was to compare the incidence of mortality, incidence/severity of renal injury and bleeding in septic ICU patients, and patients undergoing CABG surgery who have received hydroxyethyl starch 130/0.4 or albumin. Methods: This was a retrospective, single center, cohort study conducted at a 433 bed tertiary care hospital in Lexington, Kentucky. Computer generated lists provided patients who received hydroxyethyl starch 130/0.4 or albumin during inpatient stay as either a sepsis patient in the ICU or post coronary artery bypass graft patient. All cause mortality was the primary endpoint and secondary endpoints included overall renal dysfunction, incidence of bleeding, and overall length of stay. Results: A total of 89 patients were evaluated that received albumin or hydroxyethyl starch 130/0.4 alone with either septic ICU or CABG diagnosis codes. There was no significant difference in all cause mortality (p = 0.64). Overall renal dysfunction showed no statistically significance between the two groups (p = 0.66). There was no statistically significant difference between the albumin or HES 130/0.4 arms with respect to bleeding (TIMI Minimal p = 0.57, TIMI Minor p = 0.69, TIMI Major p = 0.35). Patient who received albumin had a statistically significant longer hospital overall length of stay (p = 0.003). Conclusion: There was no difference between HES 130/0.4 and albumin in mortality, renal dysfunction, and bleeding in septic ICU and CABG patients. Patients receiving albumin had an increased overall length of stay. These findings suggest that hydroxyethyl starch 130/0.4 may be safe in the studied patient populations;however, further investigation into specific HES agents should be conducted.展开更多
基金supported by the National Natural Science Foundation of China(31901257 and 32071706)School-Level Research Projects of the Yancheng Institute of Technology(xjr2019008).
文摘Dehydroabietyl polyethylene glycol glycidyl ether-grafted hydroxyethyl cellulose(HEC)polymer surfactant(DA(EO)5GE-g-HEC)was prepared using ring-opening polymerization with biobased rosin and hydroxyethyl cellulose as feedstocks.Dehydroabietyl polyethylene glycol glycidyl ether(DA(EO)5GE)was formed by condensation of dehydroabietyl alcohol polyoxyethylene ether(Rosin derivative:DA(EO)5H)and epichlorohydrin.The grafting degree of DA(EO)5GE-g-HEC was manipulated by adjusting the mass ratio of HEC and DA(EO)5GE and confirmed by EA.According to the formula,when m(HEC)/m(DA(EO)2GE)was 1:1~1:5,the grafting rate of DA(EO)5GE in DA(EO)5GE-g-HEC varied from 34.43%to 38.33%.The surface activity and foam properties of DA(EO)5GE-g-HEC aqueous solution were studied.The results showed that with the increase in grafting rate,the critical micellar concentration(CMC)in aqueous solution changed from 1.28 to 0.96 g/L.The results of the thermogravimetric analysis showed that the temperature range of the main stage of mass loss of DA(EO)5GE-g-HEC was 310°C~410°C,and the thermal decomposition processes of the samples with five mass ratios were similar.An oil in water emulsion was prepared by choosing cyclohexane as the oil phase and DA(EO)5GE-g-HEC as the emulsifier.The effect of DA(EO)5GE-g-HEC mass fraction on emulsion particle size and stability was analyzed.The results suggested that when the oil-water ratio was 8:2 with 0.4%emulsifier,the emulsion droplets were the smallest in terms of particle size and were the most stable.The rheological test results showed that the apparent viscosity decreased with the increase in shear rate and showed a typical elastic gel phenomenon.
文摘A series of homo and copolymers of styrene (ST) and 2-hydroxyethyl methacrylate (HEMA) in three different media (bulk, tetrahydrofuran, and benzene) have been investigated by free radical polymerization method. The samples obtained from the synthesis were characterized by Fourier Transform-Infrared spectroscopy (FT-IR), proton nuclear magnetic resonance spectroscopy (<sup>1</sup>H NMR), atomic force microscopy (AFM), and differential scanning calorimetry (DSC). The results show that the synthesis of the polymers is more feasible under neat conditions rather than solvent directed reaction. Moreover, the DSC data shows that the polystyrene obtained is amorphous in nature and therefore displayed only a glass transition signal rather than crystallization and melting peaks. In addition, this study indicates that homolopolymerization of styrene via free radical polymerization tends to be preferable in less polar solvents like THF than in non-polar solvents like benzene. Benzene might destabilize the formation of the reactive radicals leading to the formation of the products. In summary, the homolpolymerization of styrene is more feasible than the homopolymerization 2-hydroxyethyl methacrylate under the experimental setup used. Styrene is more reactive than 2-hydroxyethyl methacrylate than free radical polymerization reaction due in part of the generation of the benzylic radical intermediate which is more stable leading to the formation of products than alkyl radical which are less stable. Furthermore, polymerization of styrene under neat conditions is preferable in solvent-assisted environments. The choice of solvent for the synthesis of these polymers is crucial and therefore the selection of solvent that leads to the formation of a more stable reaction intermediate is more favorable. It is worth noting that the structure of the proposed copolymer consists of a highly polar and hydrophilic monomer, 2-hydroxyethyl methacrylate and a highly non-polar and hydrophobic monomer, styrene. These functionalities constitute an amphiphilic copolymer with diverse characteristics. A plausible explanation underlying our observations is that the reaction conditions employed in the synthesis of these copolymers might not be the right route required under free radical polymerization.
文摘Waterborne coatings often delaminate and settle during long-term storage,requiring the addition of thickeners.The effects of nanofibrillated cellulose(NFC)and the commonly used thickener,hydroxyethyl cellulose(HEC),on the storage stability of waterborne coatings were compared in this study.The morphology of NFC was characterized using infrared spectroscopy(FT-IR)and scanning electron microscopy(SEM).The rotational viscosity and rheological properties of the waterborne coatings with NFC and HEC were tested.Stationary settling experiments were also conducted at different temperatures to compare the difference of NFC and HEC on improving the storage stability of the waterborne coatings.The results showed that the waterborne coating with NFC exhibited pseudoplastic fluid characteristics;a small addition of NFC can achieve the same improvement effect on the storage stability of waterborne coatings as HEC.Further,the improvement effect of NFC was not affected by temperature.The waterborne coating with NFC still exhibited good storage stability at high temperatures,which was significantly superior to that of HEC.Therefore,NFC is a feasible agent for improving the prolonged storage stability and warming-induced delamination of waterborne coatings.
文摘The reaction of 3-nitro-4-chlorobenzenesulfinic acid and ethylene oxide to obtain 2-nitro-4-(β-hydroxyethylsulfonyl)chlorobenzene had been studied. Except hydroxyethylation on the sulfur atom of 3-nitro-4-chlorobenzenesulfinic acid to form the target product, 2-nitro-4-(β- hydroxyethylsulfonyl)chlorobenzene, there presented three kinds of side reactions: 1. Condensation and elimination of HCI to form biphenyl sulfone derivatives; 2. Addition to give bisulfonyl ethane derivative via vinyl sulfone; and 3. Hydroxylethylation on O-atom to produce hydroxylethylsulfinate due to the tautomerism of sulfinic acid.
基金Project(2007168303) supported by Guangdong-Hong Kong Technology Cooperation Funding
文摘Two kinds of UV curable polyurethane acrylate oligomers (PUPA and PUCA) were synthesized via the addition reaction between isophorone diisocyanate (IPDI) and polyethylene glycol monoacrylate (PEA6) or polycaprolactone modified hydroxyethyl acrylate (PCLA2). The structures of PUPA and PUCA were characterized by Fourier transform infrared spectroscopy (FT-IR), IH nuclear magnetic resonance (^H NMR), gel permeation chromatography (GPC) and differential scanning calorimeter (DSC), and the thermal stability and dynamic mechanical thermal properties of their cured films were measured by thermogravimetric analysis (TGA) and dynamic mechanical analysis (DMA), respectively. The viscosity of the oligomers and mechanical properties of the cured films were also studied. The results show that both oligomers have narrow molecular weight distribution. The viscosity of PUPA is 2.310 Pa.s at 25 ℃, while that of PUCA is: up to 3.980 Pa-s. The UV cured PUPA and PUCA films have homogeneous phase structure, and the PUCA film shows higher glass transition temperature and storage modulus. Furthermore, the PUCA film possesses better mechanical properties than PUPA, while the latter shows better alkali resistance.
基金supported by the National Key Technology R&D Program of the Ministry of Science and Technology(2013BAB01B02)
文摘Hydroxyethyl chitosan (HE-chitosan) is a water-soluble derivative of chitosan with many apparent biological properties. For example, it is non-toxic and rapidly biodegradable. Moreover, HE-chitosan has advantages in water-solubility, moisture retention and gelling property due to its hydroxyethyl group. However, the biocompatibility and biodegradability of this multifimctional de- rivative have rarely been documented although they are critical for its application in biomedical and clinical treatments. The purpose of this work was to evaluate the biosafety of HE-chitosan, and draw important clues for its diverse applications. HE-chitosan was synthesized and characterized its chemical structure with FTIR. Its molecular weight (Mw) was determined by gel permeation chro- matography (GPC), and its deacetylation degree (DD) was investigated through potentiometric analysis. The cytotoxicity of HE-chitosan on mouse fibroblast cell L929 was tested. The biocompatibility and biodegradability of HE-chitosan in rat and rabbit were evaluated. The FTIR results indicated that the hydroxyethyl groups were linked to C6 of chitosan. The GPC analysis confirmed that its Mw was about 90.01 kDa. It was also demonstrated that HE-chitosan had excellent biocompatibility and biodegradability in vivo and had no cytotoxicity on L929. These findings indicated that HE-chitosan can potentially be applied as a biomaterial in tissue engineering, drug delivery, and other biomedical fields.
基金the National Natural Science Foundation of China(No.20372018)
文摘An efficient protocol for the synthesis of N^6-(2-Hydroxyethyl)adenosine and its analogues through nucleophilic substitution was developed. All the reactions were completed in 10 rain under microwave irradiation. Using water as solvent makes our method eco-friendly and easy to handle with.
基金This project was supported by the National Natural Science Foundation of China(No.50372028)
文摘A new bicadmium(??) complex [Cd2L](ClO4)2?1.25H2O (C28H35Cd2Cl4N6O13.25) was synthesized and characterized by X-ray diffraction and ES mass spectral analyses. It crystallizes in the triclinic system, space group P1 with a = 15.630(3), b = 15.990(3), c = 16.330(3) ?, α = 89.90(3), β = 68.87(3), γ = 87.94(3)o, V = 3804.1(13) ?3, Mr = 1034.22, Z = 4, F(000) = 2060, Dc = 1.806 g/cm3, T = 293(2) K, μ = 1.468 mm-1 and λ = 0.71073 ?. The structure was refined to R = 0.0779 and wR = 0.1960 for 7034 observed reflections with I > 2σ(I).
文摘The thermal decomposition process was studied by the TG–DTA analyzer. The results show that the decomposition process of sodium hydroxyethyl sulfonate consisted of three stages: the mass loss for the first, the second and third stages may be about the groups of CH_3CH_2OH, CH_3CHO and SO_2 volatilized, respectively. The decomposition residuum of three stages was analyzed by FT-IR, and the results of FT-IR agreed with the decomposition process predicted by theoretical weight loss. The specific heat capacity of sodium hydroxyethyl sulfonate was determined by differential scanning calorimetry(DSC). The melting temperature and melting enthalpy were obtained to be 465.41 K and 25.69 kJ·mol^(-1), respectively. The molar specific heat capacity of sodium hydroxyethyl sulfonate was determinated from 310.15 K to 365.15 K and expressed as a function of temperature.
文摘BACKGROUND Accidental dural puncture(ADP)and subsequent post-dural puncture headache(PDPH)remain common complications of epidural procedures for obstetric anesthesia and analgesia.No clear consensus exists on the best way to prevent PDPH after ADP.CASE SUMMARY We report our findings in twenty parturients who underwent an incorporated strategy of epidural analgesia followed by epidural hydroxyethyl starch(HES)to prevent PDPH after ADP with a 16-gauge Tuohy needle during epidural procedures.ADP with a 16-gauge Tuohy needle occurred in nine parturients undergoing a cesarean section(CS)and in eleven parturients receiving labor analgesia.An epidural catheter was re-sited at the same or adjacent intervertebral space in all patients.After CS,the epidural catheter was used for postoperative pain relief over a 48-h period.After delivery in eleven cases,epidural infusion was maintained for 24 h.Thereafter,15 mL of 6%HES 130/0.4 was administered via the epidural catheter immediately prior to catheter removal.None of the parturients developed PDPH or neurologic deficits over a follow-up period of at least two months to up to one year postpartum.CONCLUSION An incorporated strategy of epidural analgesia followed by epidural hydroxyethyl starch may have great efficacy in preventing PDPH after ADP.
文摘The thermal behavior of thermotropic hydroxyethyl cellulose acetate (HECA)/polyethylene (PE) blends has been studied by DSC. It is found that the blends of HECA and PE are immiscible but the crystallization of PE is affected by HECA chains in the blends with more than 50% HECA, which results in the subordinate crystallization of PE and the formation of imperfect structures in the PE crystals. The imperfection of PE crystals in the blends can be eliminated after annealing at 393K.
基金the National Natural Science Foundation of China(No.50773068).
文摘Environmentally friendly biocomposites were prepared by blending wheat gluten(WG)as a matrix, hydroxyethyl cellulose(HEC)as a filler,and glycerol as a plasticizer,followed by thermo-molding of the mixture at 120°C for crosslinking the matrix.Moisture absorption,tensile properties,dynamic mechanical analysis,and dynamic rheology were evaluated in relation to the glycerol content.Tensile strength and modulus drop dramatically with increasing glycerol content,which is accompanied by significant depression in the glass transition temperature and improvement in the extensibility of the biocomposites.
文摘The position and quantity of the hydroxyethyl groups in hydroxyethyl starch (HES) were studied by GC/MS and NMR. Quantitative characterization was carried out based on the results of both methods.
基金Supported by the National Natural Science Foundation of China(No.212620302 and 0962017)the Natural Science Foundation of Gansu Province(No.1107RJZA263)
文摘The title compound, 2-O-(2-hydroxyethyl)-D-glucose (CsH1607, Mr= 224.21), has been synthesized and its structure was characterized by using NMR spectrum and X-ray single-crystal diffraction. This molecule crystallizes in the monoclinic system, space group P21, with a = 8.399(17), b = 6.620(14), c = 9.81(2) A, β = 115.110(17)°, V= 493.7(18) A3, Z = 2, Dc = 1.508 mg/m3,/1 = 0.13 mm-1, F(O00) = 240, the final R = 0.0464 and wR = 0. l 15 for 152 ] observed reflections (1 〉 2a(I)). X-ray crystal structure analysis revealed that the conformation of the pyranosyl ring existed in a slightly distorted act chair conformation (Cremer-Pople puckering parameters of Q = 0.573(4) A, 0 = 6.7(3)0 and = -5.2(2)°). The molecule exists as a monomer in the solid state, whose conformation is stabilized via multiple inter- and intramolecular hydrogen bonds.
文摘Nineteen L-N-2-hydroxyethylamino acids and L-N,N-bis(2-hydroxyethyl)amino acids were prepared from the reaction of chlorohydrin with L-alanine,L-valine,L-leucine,L-isoleucine,L- phenylalanine,L-serine,L-thrcunine,L-glutamic acid,L-aspartic acid and glycine.L-N,N,N',N'-tetra (2-hydroxyethyl)cystine was prepared by the reaction of L-cystine with chlorohydrin.
文摘A new blend of poly(2-hydroxyethyl methacrylate) (PHEMA) with poly (ethylene glycol) (PEG) was prepared. The results from solid-state NMR indicate that the PHEMA/PEG(88:12, w/w) blend is miscible on a molecular level.
文摘Purpose: The primary aim of this study was to investigate volume effect and safety of up to 50 mL/kg BW 6% hydroxyethyl starch (HES) 130/0.4 in adult and pediatric patients undergoing major elective surgery. The need to infuse human albumin may be reduced or avoided in Japan if these large doses 6% HES 130/0.4 can be infused. Methods: The study was an uncontrolled, open-labeled, multi-center trial. Fifteen adult and 5 pediatric patients undergoing major elective surgery received 6% HES 130/0.4 (Voluven®) with a maximum dose of 50 mL/kg from the start of surgery until 2 hours after the end of surgery according to a treatment algorithm. The primary efficacy endpoint was the volume effect of 6% HES 130/0.4 determined by the volume of saved albumin during the investigational period and the time course of hemodynamic stability in adult and pediatric patients. Safety parameters were fluid balance, hemodynamic and laboratory parameters ECG, local and systemic tolerance and adverse events. Results: Adult patients received a mean of 32.0 mL/kg of 6% HES 130/0.4. For 12 out of 15 adult patients an average amount of 1033.8 mL (18.6 mL/kg) albumin could be saved. The other 3 adult patients did not receive more than 1000 mL of HES 130/0.4. All pediatric patients received approximately 50 mL/kg of HES 130/0.4;for these patients an average amount of 39.9 mL/kg body weight albumin could be saved. The majority of adult patients, and all pediatric patients were hemodynamically stable at all 3 time points. The observed changes of the assessed laboratory parameters including hematological and coagulation parameters or in any other safety parameter determined did not reveal any safety concern related to the administration of 6% HES 130/0.4 up to doses of 50 mL/kg body weight. Conclusion: The study results indicate that 6% HES 130/0.4 has a reliable volume effect, could contribute to significant human albumin savings and was safe and well tolerated up to a maximum dose of 50 mL/kg body weight in adult and pediatric patients undergoing major elective surgery.
文摘The copolymerization of 2-hydroxyethyl acrylate (HEA, M//1) and methyl methacrylate (MMA, M//2) in cyclohexanone was studied. The multiple experiments of solution copolymerization with low conversion were carried out at two sensitive composition feed points at 60, 80, 100, 120 and 140 degree C, respectively. The composition of the copolymers was analyzed by **1H-NMR. The reactivity ratios which were estimated by the Error-in-Variable Method (EVM) of Mayo-Lewis equation were found to be r//1 equals 0.328, r//2 equals 1.781 for 60 degree C; 0.375, 1.709 for 80 degree C; 0.406, 1.654 for 100 degree C; 0.439, 1.540 for 120 degree C and 0.455, 1.400 for 140 degree C, and the 95% joint confidence intervals of the reactivity ratios were also determined. According to r//1 and r//2, Arrhenius relations and the activity energy difference between the homo- and cross-propagation were calculated. (Author abstract) 12 Refs.
基金the National University of San Luis(Project 22/Q228)INQUISAL-CONICET(Instituto de Quimica de San Luis-Consejo Nacional de Investigaciones Cientificas y Tecnicas, PIP-CONICET 11220100100405) for the financial support
文摘A simple,eco-friendly.sensitive and economic flow injection spectrofluorimetric method was developed for the determination of O-(β-hydroxyethyl)rutosidcs.The procedure was based on the use of an anionic surfactant such as sodium dodecyl sulfate to provide an appreciable O-(β-hydroxyethyl)rutosides fluorescence enhancement,increasing considerably the sensitivity of detection.All the variables affecting the fluorescence intensity were studied and optimized.The flow rate was 5 mL/min with detection at 450 nm(after excitation at 346 nm).A linear correlation between drug amount and peak area was established for 0-(β-hydroxyethyl)rulosides in the range of 0.01-200 μg/mL with a detection limit of0.001 μg/mL(s/n = 3).Validation processes were performed by recovering studies with satisfactory results.The new methodology can be employed for the routine analysis of 0-(P-hydroxyethyl)rutosides in bulks as well as in commercial formulations.
文摘Background: In June 2013, the FDA issued a Black Box Warning on synthetic colloids resulting from data indicating an increased risk of mortality, renal injury, and excess bleeding incidence in septic patients admitted to the Intensive Care Unit (ICU), and patients undergoing coronary artery bypass graft (CABG) surgery. The purpose of this study was to compare the incidence of mortality, incidence/severity of renal injury and bleeding in septic ICU patients, and patients undergoing CABG surgery who have received hydroxyethyl starch 130/0.4 or albumin. Methods: This was a retrospective, single center, cohort study conducted at a 433 bed tertiary care hospital in Lexington, Kentucky. Computer generated lists provided patients who received hydroxyethyl starch 130/0.4 or albumin during inpatient stay as either a sepsis patient in the ICU or post coronary artery bypass graft patient. All cause mortality was the primary endpoint and secondary endpoints included overall renal dysfunction, incidence of bleeding, and overall length of stay. Results: A total of 89 patients were evaluated that received albumin or hydroxyethyl starch 130/0.4 alone with either septic ICU or CABG diagnosis codes. There was no significant difference in all cause mortality (p = 0.64). Overall renal dysfunction showed no statistically significance between the two groups (p = 0.66). There was no statistically significant difference between the albumin or HES 130/0.4 arms with respect to bleeding (TIMI Minimal p = 0.57, TIMI Minor p = 0.69, TIMI Major p = 0.35). Patient who received albumin had a statistically significant longer hospital overall length of stay (p = 0.003). Conclusion: There was no difference between HES 130/0.4 and albumin in mortality, renal dysfunction, and bleeding in septic ICU and CABG patients. Patients receiving albumin had an increased overall length of stay. These findings suggest that hydroxyethyl starch 130/0.4 may be safe in the studied patient populations;however, further investigation into specific HES agents should be conducted.