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    25 October 2018, Volume 38 Issue 5 Previous Issue    Next Issue
    Synthesis and Application Progress of Biomass Modified Waterborne Polyurethane
    DONG Fuhao, CHEN Lijing, GUO Jiawen, XU Xu, WANG Shifa, LIU He
    2018, 38 (5):  1-8.  doi: 10.3969/j.issn.0253-2417.2018.05.001
    Abstract ( 598 )   PDF (684KB) ( 1079 )   Save
    In this paper, the development of waterborne polyurethane(WPU) modified by biomass both in China and abroad in recent years was reviewed. The progresses of waterborne polyurethane modified bymain biomass raw materials such as vegetable oil, starch, cellulose and rosin wereintroduced, respectively. Moreover, the applications of waterborne polyurethane modified by biomass in coatings, adhesives and other aspects of the application were summarized as well. In addition, the prospects of waterborne polyurethane modified by biomass werepointed out.
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    Preparation and Electrochemical Performances of Fe3O4@C Nanosheet Electrode Material for Supercapacitors
    WANG Ao, SUN Kang, JIANG Jianchun
    2018, 38 (5):  9-16.  doi: 10.3969/j.issn.0253-2417.2018.05.002
    Abstract ( 462 )   PDF (2364KB) ( 692 )   Save
    Two dimensional Fe3O4@C nanosheet was prepared by facile and effective in situ deposition crystallization followed by pyrolysis route using sucrose as carbon source and sodium chloride as template. The structure and electrochemical energy storage properties of Fe3O4@C nanosheet were characterized. The results showed that Fe3O4@C nanosheet is made of 2D graphitic carbon nanosheets, which uniform Fe3O4 nanoparticles were embedded. The thickness of Fe3O4@C nanosheet was less than 100 nm with the specific surface area 255 m2/g and average pore size 3.79 nm, and the mass fraction of Fe3O4 was 36.98%. Besides, the results of the electrochemical energy storage performance showed that Fe3O4@C nanosheet exhibited high specific capacitance and excellent rate capability (436 F/g at 1 A/g, and still up to 332 F/g at 20 A/g). However, the cycle stability of it was poor, over 500 cycles at 10 A/g, the specific capacitance dropped to 178 F/g, only 50.71% of the initial value.
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    Preparation and Properties of Poly(Lactic Acid) Stereocomplex Containing Glucose Groups
    CAO Dan, MING Wei, QI Liyan, ZHAO Yinping, GAO Qinwei
    2018, 38 (5):  17-22.  doi: 10.3969/j.issn.0253-2417.2018.05.003
    Abstract ( 622 )   PDF (974KB) ( 619 )   Save
    In order to improve the thermal performance and hydrophilcity of poly(lactic acid) materials, the copolymers such as poly(L-lactic acid-co-glucose) (PLLAG) and poly(-lactic acid-co-glucose) (PDLAG) were prepared by direct polymerization with lactic acid and glucose as raw materials. Then the stereocomplex of PLLAG and PDLAG were prepared by solution blending method, and thus stereocomplex materials of poly(lactic acid) with glucose groups (sc-PLAG) were obtained. sc-PLAG was charterized by FT-IR, DSC, XRD, POM and contact angle method. The results showed that stereocomplex crystal (SC) of sc-PLAG was formed by the interaction between L-lactic acid units of PLLAG and D-lactic acid units of PDLAG at rapid crystallization rate, and SC possessed regular spherulite morphology. sc-PLAG only possessed stereocomplex crystalline as the mass contents of PLLAG in sc-PLAG were from 40% to 60%, and sc-PLAG might have homogeneous crystalline (HC) and SC as the amounts of PLLAG in sc-PLAG were more than 60% or less than 40%. The melt points (Tm) of stereocomplex crystal of all sc-PLAG samples with the mass fraction of glucose 5% were 197.5℃, nearly irrelevant to PLLAG amount. The glass transition temperature(Tg) of sc-PLAG, Tm of SC, and the contact angle of sc-PLAG decreased with increasing glucose mass fraction, while sc-PLAG crystallinity increased with increasing glucose mass fraction, reaching to the maximum of 53.84%. In conclusion, the stereocomplex of poly(L-lactic acid) with glucose groups improves the crystallization, hydrophilcity, and thermal performance.
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    Synthesis of Sodium Maleopimaric Acid Long Chain Alkyl (Alkylene) Amines and Their Antifeedant Activity Against Agrotis ypsilon
    ZHAI Zhaolan, YAN Xinyan, XU Ji, SONG Zhanqian, SHANG Shibin, RAO Xiaoping
    2018, 38 (5):  23-29.  doi: 10.3969/j.issn.0253-2417.2018.05.004
    Abstract ( 530 )   PDF (707KB) ( 441 )   Save
    With maleopimaric acid, dodecylamine, tetradecylamine,hexadecylamineand octadecylamine as the main raw materials, disodium maleopimaric acid amide(Cn-MPA-2Na, n=12, 14, 16, 18) were synthesized through amidation reaction and acid-base neutralization, and their structures were characterized by IR and 1H NMR. The antifeedant activities of Cn-MPA-2Na (n=12, 14, 16, 18)and sodium maleopimaric acid long chainalkylene amines (Cn-MPA-Na, n=12, 14, 16) reported in reference against Agrotis ypsilon were investigated using the method of leaf disc. The results showed that both Cn-MPA-2Na (n=12, 14, 16, 18) and Cn-MPA-Na (n=12, 14, 16) show good water solubility at room temperature, and the solubility of Cn-MPA-2Na was above 300 g/L. Both the length of alkane and the number of sodium carboxylate in soluble sodium maleopimaric acid long chain alkyl (alkylene) amines showed little influences on its antifeedant activities against A. ypsilion. And C12-MPA-2Na, C18-MPA-2Na and C14-MPA-Na showed strong antifeedant activities against A. ypsilon. The 50% antifeedant concentrations(AFC50) for C12-MPA-2Na, C18-MPA-2Na and C14-MPA-Na were 0.51, 0.54 and 0.77 g/L, respectively.
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    Preparation of Lignin Based Carbon Quantum Dots and Their Application in Fe3+ Detection
    GAO Xuexia, ZHOU Xi, LIU Meihong, WANG Chunpeng, CHU Fuxiang
    2018, 38 (5):  30-36.  doi: 10.3969/j.issn.0253-2417.2018.05.005
    Abstract ( 773 )   PDF (2635KB) ( 841 )   Save
    Carbon quantum dots (CQDs) were prepared from alkali lignin by hydrothermal reaction in presence of strong acid, and the synthesis conditions were optimized.The results showed that the optimal synthesis conditions were the dosage of alkali lignin 1.3 g, reaction temperature 180℃, reaction time 12 h, the dosage of NaBH4 1.3 g. The morphology and size of CQDs were characterized by transmission electron microscopy (TEM) and laser particle size analysis (DLS). The results showed that CQDs had good dispersion and uniform size distribution, and the average particle size was about 3.5 nm. The structure and composition of CQDs were characterized by infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS), which indicated that the surface of CQDs contained a large number of hydroxyl, carboxyl and other oxygen-containing functional groups. In addition, the optical properties of CQDs were characterized by ultraviolet visible spectroscopy (UV-vis) and fluorescence spectra(FL), and the fluorescence quantum yield was 17.3%. Using CQDs as probe, it was used to detect Fe3+ by colorimetric method. The results showed that CQDs had good selectivity to Fe3+, its detection range was 0-400 μmol/L, and the detection limit could reach 0.136 μmol/L. At the same time, the low cytotoxicity of the CQDs made them having potential applications in biological medicine.
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    Extraction Technology for Total Polyphenols from Eucalyptus grandis×E. urograndis Bark and Their Bioactivities
    JIANG Ping, ZHANG Qian, ZHAO Yajie, LU Tingting, WANG Fei, ZHANG Liping
    2018, 38 (5):  37-44.  doi: 10.3969/j.issn.0253-2417.2018.05.006
    Abstract ( 591 )   PDF (994KB) ( 743 )   Save
    The optimum extraction conditions of total polyphenols from Eucalyptus grandis×E. urograndis bark via enzymolysis treatment and ultrasonic-assisted coupling extraction method and ultrasonic extraction method were investigated by using orthogonal experiment. Vitro antioxidant activities of different solvent extracts by ultrasonic extracts were studied and the ethyl acetate extract exhibited stronger antioxidant activity. Then, 11 kinds of fractions(Fr.1-Fr.11) and a purified compound (Pu1) were separated from the ethyl acetate extract by AB-8 macroporous resin. The optimum crafts for ultrasonic extraction method were 60% ethanol, ultrasonic time 50 min, ratio of material-liquid 1:12 (g:mL), ultrasonic temperature 60℃, and the yield of total polyphenols was 5.12%. The optimum crafts for enzymolysis treatment and ultrasonic-assisted coupling extraction method were 0.15 g/L enzyme concentration,enzymolysis temperature 50℃,enzymolysis time 50 min,enzyme solution pH 5.0, combining with ultrasonic extraction, the yield of total polyphenols was 6.23%. The results of radical scavenging capacity assay showed that the scavenging rates of Fr.5, Fr.6, Fr.7 and Fr.8 active fractions at 50 mg/L were greater than 60%, and they had high antioxidant activity. The IC50 of the active compound Pu1 was 8.99 mg/L, less than that of Vc(10.46 mg/L), indicating significant antioxidant activities. Moreover, the phenolic content of the active fractions showed positive correlation with their antioxidant activities (R=0.944 8,P<0.000 1). The structure of compound Pu1 was characterized by UV, FT-IR, MS and NMR and the results showed that its molecular formula and molar mass were C21H22O14 and 498, respectively, which was named as 2'-methoxy-hexadylic biphenylate-4-O-α-L-rhamnoside.
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    Preparation and Properties of Ultraviolet-curing Modified Rosin Methacrylate
    FENG Xiaolong, LI Xiaotong, HUANG Lingge, GUO Kai
    2018, 38 (5):  45-52.  doi: 10.3969/j.issn.0253-2417.2018.05.007
    Abstract ( 679 )   PDF (1053KB) ( 721 )   Save
    Maleopimaric anhydride(MPA) was firstly synthesized by Diels-Alder addition reaction of resin acid and maleic anhydride, then the MPA reacted with hexamethylene diamine to prepare maleopimaramide acid(MPAA), finally, modified rosin methacrylate(MRMA) was synthesized via the reaction between maleopimaramide acid and glycidyl methacrylate. The chemical structure of intermediates and goal product were characterized by FT-IR and 1HNMR. The ultraviolet(UV)-curing properties of MRMA film were investigated. The results showed that MRMA was solvable in usual active acrylic esters. The results of DSC and TG showed that the glass transition temperature(Tg) of the UV-curing coating was 124.3℃ and the peak value in DTG was 418.4℃. The hardness and water-absorption of UV-curing film were 2H and below 5%, respectively. The adhesive force of UV-curing coating on polypropylene film was grade 0. The UV-curing film showed good resistances to acid, alkali, and water. All these indicated that MRMA would have a good prospect of applications for UV-curing coating, printing ink, and adhesive. The effects of the type and dosage of active diluent(AD) on UV-curing coating were also studied. The results showed that UV-curing MRMA coating with butyl acrylate(BA) as AD had good comprehensive performance. The adhesive force, tensile strength, glass transition temperature, and hardness of UV-curing MRMA/BA coating increased with the increase of MRMA content, while the elongation at break increased first and then decreased.
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    Co-pyrolysis Process of Waste Tire and Biomass
    WU Kai, ZHU Jinjiao, ZHU Yuezhao, YANG Ye
    2018, 38 (5):  53-60.  doi: 10.3969/j.issn.0253-2417.2018.05.008
    Abstract ( 576 )   PDF (750KB) ( 683 )   Save
    The co-pyrolysis process of waste tire and biomass at various blend ratios, heating rate and granular size were investigated using thermogravimetric analysis. HSC calculate simulation software was used to simulate the release rule of pyrolysis gas. The results showed that the co-pyrolysis process of waste tire and biomass was divided into three stages:drying stage (20-200℃), gasification and pyrolysis stage (200-500℃), secondary cracking stage (500-800℃). With the waste tire blend ratios decreasing from 100% to 0, the initial pyrolysis temperature decreased from 358.0℃ to 288.5℃, and the terminated pyrolysis temperature decreased from 473.0℃ to 361.6℃. With the increasing of heating rate and granular size, the maximum pyrolysis reaction rate and terminated pyrolysis temperature increased, the reaction moved toward to high temperature without influence on terminal reaction products. Pyrolysis kineties of the co-pyrolysis process was studied by Coats-Redfern method. The results showed that the activation energies of co-pyrolysis process (200-500℃) were between 18.61-40.86 kJ/mol, and decreased with the decreasing of waste tire blend ratio. HSC simulation showed that with the decreasing of waste tire blend ratios, content of H2, CO, CO2 increased, but CH4 decreased. According to the ratio of amount of gas and pyrolysis properties, it was found that more combustible gas could be obtained at blend ratio of waste tire 40%-60%.
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    Influence of Pyrolysis Parameters on Properties of Pyrolyzed Wood Vinegar
    LU Xincheng, JIANG Jianchun, SUN Kang, SUN Yunjuan
    2018, 38 (5):  61-69.  doi: 10.3969/j.issn.0253-2417.2018.05.009
    Abstract ( 616 )   PDF (1026KB) ( 634 )   Save
    The pyrolysis of Chinese fir sawdust in fixed bed was investigated. The influence of pyrolysis conditions (such as pyrolysis temperature, heating rate and flow rate of nitrogen) on properties of wood vinegar was discussed. The results showed that pyrolysis temperature was the main factor that effected the preparation and properties of wood vinegar. The yield of wood vinegar and refined wood vinegar were 57.13% and 38.20% under the pyrolysis conditions of pyrolysis temperature 450℃, heating rate 10℃/min and N2 flow 100 mL/min. Acids and phenols were the primary components in wood vinegar which occupied about 2/3 of total content. Organic component of wood vinegar was obviously effectedby pyrolysis conditions, pyrolysis temperature effected the content of acids,phenols and alcohols, heating rate effected the content of acids and alcohols, the flow rate of nitrogen effected the content of phenols and alcohols, the contents of aldehydes, ketones and esters were almost not effected by conditions.
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    Preparation and Characterization of Cellulose Acetate Films Derived from Bamboo
    SHI Chun, LI Tiancheng, YANG Jing, YANG Haiyan, DENG Jia, SHI Zhengjun
    2018, 38 (5):  70-76.  doi: 10.3969/j.issn.0253-2417.2018.05.010
    Abstract ( 574 )   PDF (1423KB) ( 680 )   Save
    To explore the better raw material for cellulose acetate film, cellulose isolated from Dendrocalamus sinicus (BC), bamboo pulp cellulose(PC) and commercially available microcrystalline cellulose(MC) were used as raw materials,which respectively react with acetic anhydride used as acetylating agent in presence of concentrated sulfuric acid used as catalyst, to prepare bamboo cellulose acetate from D. sinicus (BCA), bamboo pulp acetylated cellulose(PCA) and microcrystalline cellulose acetate(MCA). Three cellulose acetate films were then prepared and their properties were investigated. The results showed that the active hydroxyl of BC had the most substituted activity by acetyl groups. The content of acetyl group of BCA could reach 48.54%, slightly higher than that of MCA(46.06%) and PCA(44.13%). The BCA film's tensile strength and elongation at break of BCA film reached 45.97 MPa and 2.1%, which were significantly stronger than those of PCA film and MCA film. The transmittance of BCA film >90%. It also exhibited the strongest hydrophobicity, with the contact angle of 92.9°. Moreover, the surface of the BCA film was relatively smooth and the structure was the most compact. Additionally, BCA film also showed high thermal stability. Therefore, BC was the best raw material for the preparation of cellulose acetate film, while compared to PC and MC.
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    Extraction of Chromogenic Component from Pterocarpus macrocarpus Kurz. Heartwood and Its Effect on Wood Color
    ZHANG Peng, WEI Yanxia, LIU Yang, CHEN Yao, GAO Jianmin, FAN Yongming
    2018, 38 (5):  77-84.  doi: 10.3969/j.issn.0253-2417.2018.05.011
    Abstract ( 516 )   PDF (1111KB) ( 714 )   Save
    Two groups of Pterocarpus macrocarpus Kurz. heartwood with different color were used as research objects in the present study to reveal its chromogenic mechanism. Extractives from water, benzene-alcohol, and dioxane were analyzed. Then, the color parameter and structure of extractives was measured by means of CIE Lab, FT-IR, UV-VIS and GC-MS spectroscopic analysis. It was found that P.macrocarpus wood was mainly reddish, and the deep-colored sample had a strong absorption in the green spectral region (496 nm), resulting in a higher a* value. More chromophoric components in light-colored samples were extracted with the same solvent compared with deep-colored samples. And the chromatic aberration of light-colored samples after extraction was higher than that of deep-colored samples. The chromatic aberration reached at the maximum value after extracted by 1,4-dioxane solvent compared to water and benzene-alcohol solvent. The main chromophore components in water extractive were unsaturated alcohol; in benzene-alcohol extractive, it contained unsaturated alcohol and conjugated carbonyl, benzene ring, non-conjugated carbonyl structures;in dioxane extractive, they were β-eudesmol, homopterocarpin and α-copaen-11-ol. β-eudesmol and homopterocarpin were the chromophoric substances related to the red-green axis chromaticity index a* in wood.
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    Extraction of Total Polyphenols from Eucommia ulmoides Oliver Leaves Assisted by Ultrasound-microwave and Their Antioxidant Activity
    WANG Xiang, PENG Sheng, PENG Mijun
    2018, 38 (5):  85-92.  doi: 10.3969/j.issn.0253-2417.2018.05.012
    Abstract ( 621 )   PDF (1335KB) ( 743 )   Save
    The extraction technology of total polyphenols from Eucommia ulmoides Oliver leaves was optimized by ultrasound-microwave assisted method and their antioxidant activity were investigated. Experiments were conducted to investigate the effects of 6 factors, such as ethanol volume fraction, solid-liquid ratio, ultrasound power, ultrasound extraction time, microwave power, and microwave extraction time on the yield of total polyphenols from E. ulmoides leaves by Plackett-Burman design. After screening the four significant factors including ethanol volume fraction, solid-liquid ratio, microwave power and ultrasound extraction time, the process optimization was carried out by the steepest ascent design and response surface. The optimal extraction conditions were as follows:ethanol volume fraction 46%, solid-liquid ratio 1:20.70(g:mL), microwave power 154 W, microwave extraction time 140 s, ultrasound power 350 W and ultrasound extraction time 31 min. Under this condition, the yield of total polyphenols was 8.491%, which was improved by 33.57% compared with the traditional method. The extract of total polyphenols has been obtained by optimal process and the results of antioxidant assay in vitro showed that the extract of total polyphenols from E. ulmoides leaves had obvious scavenging capacity for DPPH·, ABTS·and·OH, with the inhibitory concentration 50% (IC50) values of 31.21, 24.50 and 311.8 mg/L respectively, and the antioxidant activity is equivalent to BHT and lower than Vc.
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    Effect of Hydrogen Bonding of Ammonium-based Deep Eutectic Solvents on Cellulose Dissolution
    CHEN Zishu, ZHAO Zixuan, ZHANG Shaomeng, REN Hongwei
    2018, 38 (5):  93-99.  doi: 10.3969/j.issn.0253-2417.2018.05.013
    Abstract ( 830 )   PDF (2702KB) ( 860 )   Save
    A series of ammonium-based ammonium salts and amides were used as raw materials to prepare deep eutectic solvents(DES), namely, tetramethylammonium chloride/caprolactam(TMACl/CPL), tetraethylammonium chloride/caprolactam(TEACl/CPL), tetrabutylammonium chloride/caprolactam(TBACl/CPL), tetrabutylammonium acetate/caprolactam(TBAAc/CPL),tetrabutylammonium hydrogen sulfate/caprolactam(TBAHSO4/CPL), and tetrabutylammonium bromide/caprolactam(TBABr/CPL). The formation process of hydrogen bonds of CO-H-C and C-N-H-C between ammonium salt and caprolactam were studied by FI-IR, 1H NMR, 13C NMR and MS. Then, DES was used to dissolve cellulose. The effects of alkyl chain length, anion, time, temperature, viscosity and the hydrogen-bond network structure of DES on the dissolution of cellulose were explored, respectively. It was found that butyl had higher ability to dissolve cellulose than that of ethyl and methyl. Ac- could afford more reactive sites than Br-, Cl-, Ac- and HSO-4. TBAAc/CPL was a preferable solvent and the dissolubility of cellulose was 7.8% under 100℃ and 75 min. Moreover, the dissolution mechanism of hydrogen bond on cellulose was investigated. The results showed that the raw dense and ordered structure of cellulose were changed to coarse and disordered state,and the structure of -OH,-CH and C-O-C didn't change.The cellulose was directly dissolved in ammonium-based DES, and no other derivatives were generated. XRD analysis showed that the 2θ of cellulose before and after regeneration changed from 15.36°, 16.68°, and 22.10° to 21.99°, and the cellulose crystal form was changed from cellulose I to type Ⅱ.
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    Pretreatment of Corn Cob by the Combination of H3PO4-H2O2 and Their Effect on Enzymatic Hydrolysis Efficiency
    YING Wenjun, WU Kai, SHI Zhengjun, YANG Haiyan, ZHENG Zhifeng, YANG Jing
    2018, 38 (5):  100-106.  doi: 10.3969/j.issn.0253-2417.2018.05.014
    Abstract ( 636 )   PDF (888KB) ( 562 )   Save
    Corn cob was pretreated by H3PO4-H2O2(PHP)solution and then hydrolyzed by cellulase. The conditions of pretreatment was optimized, which was based on saccharification rate of substrate. Results showed that in pretreated corn cob under the optimized conditions of pretreatment (mass fraction of H3PO4 80%, 4 h, 50℃), the mass fraction of cellulose was 57.38%; the cellulose recovery, hemicellulose removal and lignin removal were 95.84%, 62.36% and 68.97%, respectively.As the dosage of cellulase was 10 FPIU/g glucan, the yield of 72 h enzymatic hydrolysis was 39.12%, which was 2.61 folds higher than that of the enzymatic hydrolysis yield of corn cob without pretreatment(10.84%). Using FT-IR to analyze the change of structure before and after pretreatment, the results showed that, PHP pretreatment had coordinated pretreatment effect in the pretreatment process, which could remove hemicellulose and lignin at the same time. For comparative purpose, H3PO4 (16.78%) or H2O2 pretreatment (20.71%) was used independently, to enzymatic hydrolysis of corn cob for 72 h. It was found that the yield of 72 h enzymatic hydrolysis treated by H3PO4-H2O2 pretreatment increased by 133.13% and 88.89%, respectively, while compared with that of H3PO4 or H2O2.
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    Fractionation and Characterization of Sugarcane Bagasse Kraft Lignin
    JIA Zhuan, WAN Guangcong, LI Mingfu, LUO Bin, WANG Shuangfei, MIN Douyong
    2018, 38 (5):  107-114.  doi: 10.3969/j.issn.0253-2417.2018.05.015
    Abstract ( 663 )   PDF (1467KB) ( 751 )   Save
    Kraft lignin(KL) of sugarcane bagasse extracted from bagasse pulping black liquor was successively fractionated into four fractions (e.g. F1, F2, F3 and F4) by various organic solvents (ethyl acetate, ethyl acetate/petroleum ether, and petroleum ether) according to their solubility. Kraft lignin and its three fractions(F1, F2 and F3) were comprehensively characterized by elemental composition analysis, gel permeation chromatography, Fourier transform infrared spectroscopy, and nuclear magnetic resonance including 31P, 13C, and 1H-13C HSQC NMR, respectively. The results indicated that F1, F2, F3 and F4 were respectively accounting for 59.6%, 28.4%, 10.8% and 1.2% of kraft lignin. Compared with the original kraft lignin, the molecular weight of F1 was higher and the homogeneity was better. The molecular weight and dispersity of lignin fractions F2 to F4 were smaller than those of original kraft lignin. Furthermore, the contents of methoxyl group, hydroxyl group, and inter-unit linkages, as well as the thermal properties of fractions (F1, F2, and F3), were varied with their molecular weights. The proportion of β-O-4' structure decreases with the decrease of molecular weight, and the proportion of β-5' increases with the decrease of molecular weight.
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    Properties of Phenolic Foam Modified by Lignin Depolymerized in Molten Salt Hydrate
    YANG Xiaohui, SHANG Qianqian, JIA Puyou, ZHOU Yonghong
    2018, 38 (5):  115-121.  doi: 10.3969/j.issn.0253-2417.2018.05.016
    Abstract ( 673 )   PDF (857KB) ( 681 )   Save
    In this paper, lignin was effectively depolymerized by using inorganic ionic liquid (acidic molten salt hydrate) and applied in the research of modified phenolic foam. The results showed that lignin could be effectively degraded, the relative weight average molecular weight (Mw) decreased from 3 900 to 1 600, and the polymer dispersity index (PDI) expressed by Mw/Mn also decreased from 4.10 to 1.78 markly which will lead to improvement of the stability and reproducibility in the lignin modified products. In addition, the phenolic hydroxyl content was greatly increased after lignin depolymerization, which can enhance the reactivity of lignin and lay a foundation for improving the utilization of lignin. Moreover, phenolic foam modified by 30% depolymerized lignin exhibited a good property with a compressive strength of 235 kPa, the limited oxygen index 38.1% and the coefficient of thermal conductivity 0.028 W/(m·K). These showed that the product might be non-combustible and efficient insulation materials.
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    I-Optimal Mixture Design of Compound Edible Fungi Inoculants for Bioconversion of Cinnamon Leaves into Feeding Stuff
    XU Hao, ZHANG Ning, YANG Jing, ZHAO Jian, XIE Jingcong, JIANG Jianchun
    2018, 38 (5):  122-128.  doi: 10.3969/j.issn.0253-2417.2018.05.017
    Abstract ( 525 )   PDF (812KB) ( 695 )   Save
    To achieve higher enzymes activities during fermentation process of cinnamon leaves, the synergetic and antagonistic effects among different edible fungi, as well as between edible fungi and Aspergillus oryzae, were estimated by I-optimal mixture design. The results demonstratedthat special cubic models fit the mixture design methods well. Among Pleurotus ostreatus,Flammulina velutipes, Auricularia auricular and A. oryzae, antagonistic effects were found between F. velutipes and A.auricular during enzyme production, and synergistic effects were found among the rest species. Thus, by taking advantage of synergetic effects and avoiding of antagonistic effects, two formulas were made as following:A. auricular 17.6%, P. ostreatus 44.3% and A. oryzae 38% (9.14 U/g xylanase, 1.56 U/g cellulose, 67.37 U/g plant enzyme); or F. velutipes 60% and A. oryzae 40% (5.74 U/g xylanase, 1.34 U/g cellulase, 58.39 U/g plant enzyme).
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