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Flotation of low-grade bauxite using organosilicon cationic collector and starch depressant 被引量:7
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作者 余新阳 王浩林 +2 位作者 王强强 冯博 钟宏 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第4期1112-1117,共6页
The flotation of diaspore and three kinds of silicate minerals, including kaolinite, illite and pyrophyllite, using an organosilicon cationic surfactant (TAS101) as collector and starch as depressant was investigated.... The flotation of diaspore and three kinds of silicate minerals, including kaolinite, illite and pyrophyllite, using an organosilicon cationic surfactant (TAS101) as collector and starch as depressant was investigated. The results show that both diaspore and aluminosilicate minerals float readily with organosilicon cationic collector TAS101 at pH values of 4 to 10. Starch has a strong depression effect for diaspore in the alkaline pH region but has little influence on the flotation of aluminosilicate minerals. It is possible to separate diaspore from aluminosilicate minerals using the organosilicon cationic collector and starch depressant. Further studies of bauxite ore flotation were also conducted, and the reverse flotation separation process was adopted. The concentrates with the mass ratio of Al2O3 to SiO2 of 9.58 and Al2O3 recovery of 83.34% are obtained from natural bauxite ore with the mass ratio of Al2O3 to SiO2 of 6.1 at pH value of 11 using the organosilicon cationic collector and starch depressant. 展开更多
关键词 BAUXITE reverse flotation organosilicon cationic collector starch depressant
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Cross-Linking of Sago Starch with Furan and Bismaleimide via the Diels-Alder Reaction
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作者 Henky Muljana Ivana Hasjem +5 位作者 Merianawati Sinatra Dicky Joshua Pesireron MichaelWilbert Puradisastra Ryan Hartono Kevin Yovan Hermanto Tony Handoko 《Journal of Renewable Materials》 EI 2023年第12期4039-4060,共22页
This research paper describes the synthesis of thermo-reversible cross-linking of sago starch by grafting a furan pendant group(methyl 2-furoate)onto the starch backbone,followed by a Diels-Alder(DA)reaction of the fu... This research paper describes the synthesis of thermo-reversible cross-linking of sago starch by grafting a furan pendant group(methyl 2-furoate)onto the starch backbone,followed by a Diels-Alder(DA)reaction of the furan functional group with 1,1′-(methylenedi-4,1-phenylene)bismaleimide(BM).The proof of principles was provided by FTIR and 1H-NMR analyses.The relevant FTIR peaks are the carbonyl peak(υC=O sym)at 1721 cm^(−1);the two peaks appeared after DA cross-linking,i.e.,at 1510 cm^(−1)(corresponding toυCH=CH BM aromatic rings,stretching vibrations),and at 1173 cm^(−1)(assigned to cycloadduct(C-O-C,δDA ring))while the^(1)H-NMR result shows evidence for the presence of a furan ring in the starch matrices(in the range ofδ6.3-7.5 ppm).The crosslinked starch product is indeed thermally reversible,as is evident from the appearance of exothermal(DA,temperature range of 50℃-70℃)and endothermal(retro DA,temperature range of 125℃-150℃)transitions in the DSC thermograms.This paper not only proves the thermal reversibility but also demonstrates that the final product properties(chemical,morphology,and thermal stability)can be tuned by varying the annealing temperature,BM intake,and reaction time. 展开更多
关键词 DIELS-ALDER starch biopolymers thermal-reversible cross-linking
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Insights into the swelling process and drug release mechanisms from cross-linked pectin/high amylose starch matrices 被引量:1
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作者 Fernanda M.Carbinatto Ana Do´ris de Castro +1 位作者 Raul C.Evangelista Beatriz S.F.Cury 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2014年第1期27-34,共8页
Cross-linked pectin/high amylose mixtures were evaluated as a new excipient for matrix tablets formulations,since the mixing of polymers and cross-linking reaction represent rational tools to reach materials with modu... Cross-linked pectin/high amylose mixtures were evaluated as a new excipient for matrix tablets formulations,since the mixing of polymers and cross-linking reaction represent rational tools to reach materials with modulated and specific properties that meet specific therapeutic needs.Objective:In this work the influence of polymer ratio and cross-linking process on the swelling and the mechanism driving the drug release from swellable matrix tablets prepared with this excipient was investigated.Methods:Cross-linked samples were characterized by their micromeritic properties(size and shape,density,angle of repose and flow rate)and liquid uptake ability.Matrix tablets were evaluated according their physical properties and the drug release rates and mechanisms were also investigated.Results:Cross-linked samples demonstrated size homogeneity and irregular shape,with liquid uptake ability insensible to pH.Cross-linking process of samples allowed the control of drug release rates and the drug release mechanism was influenced by both polymer ratio and cross-linking process.The drug release of samples with minor proportion of pectin was driven by an anomalous transport and the increase of the pectin proportion contributed to the erosion of the matrix.Conclusion:The cross-linked mixtures of high amylose and pectin showed a suitable excipient for slowing the drug release rates. 展开更多
关键词 High amylose starch PECTIN cross-linking SWELLING Drug delivery mechanism
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Influence of Inorganic Salts on the Adsorption of Cationically Modified Starch to Fibers 被引量:2
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作者 Nejc Zakrajsek 《Food and Nutrition Sciences》 2014年第3期245-249,共5页
The article is focused on the influence of inorganic salts on the adsorption of cationically modified starch to fibers. Results show that low concentrations of inorganic salts usually affect the process of adsorption ... The article is focused on the influence of inorganic salts on the adsorption of cationically modified starch to fibers. Results show that low concentrations of inorganic salts usually affect the process of adsorption in a positive way. Adsorption efficiency at higher concentrations, however, depends on the type of inorganic salts as well as the sequence of adding inorganic salts and starch to paper suspension. 展开更多
关键词 cationically Modified starch ADSORPTION Inorganic Salts FIBER
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Preparation of Cationic Starch by Electromagnetic Dry Process (EMDP)
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作者 Yue Shitai (Institute of Teoretical Chemistry,Jilin University,Changchun)Zhang Lijun (Changchun Institute of Optics and Fine Mechanics,Changchun) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1990年第4期402-404,共3页
Introduction Cationic starches are a series of products of which various sorts with different properties and usages can all be produced via cationic reactions by using different types of etherification agents under di... Introduction Cationic starches are a series of products of which various sorts with different properties and usages can all be produced via cationic reactions by using different types of etherification agents under different conditions. As an additive and strengthening agent, 展开更多
关键词 Electromagnetic dry process Wet method cationic etherification agent cationic starch
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Synthesis, Characterization and Utilization of Starch Hydroxypropyl Sulphate for Cationic Dye Removal
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作者 Aly A. Hebeish Amal A. Aly 《International Journal of Organic Chemistry》 2014年第3期208-217,共10页
The best conditions for synthesis of starch hydroxypropyl sulphate as per the dry method were firstly established. This was done through a thorough investigation into factors affecting the synthesis including concentr... The best conditions for synthesis of starch hydroxypropyl sulphate as per the dry method were firstly established. This was done through a thorough investigation into factors affecting the synthesis including concentrations of both the NaOH catalyst and the 2-hydroxy-3-chloropropyl sulphate along with duration and temperature of the reaction. The resultant newly synthesized 2-hydroxy-3-chloropropyl sulphate was then reacted with starch to obtain starch hydroxypropyl sulphate ultimately. After being characterized by making use of IR spectroscopy analysis and scanning electronic microscope, the starch hydroxypropyl sulphate samples were submitted to evaluation for cationic dye removal using Methylene Blue (MB). Cationic dye removal was studied under a variety of conditions. Factors involved encompass initial dye concentration, duration, sulphur %, pH and adsorbent dose. 100% dye removal could be achieved under certain conditions which were described in the text. 展开更多
关键词 starch cationic DYE starch Sulphate DYE Removal METHYLENE Blue
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The effect of cations on gelation of cross-linked polymers
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作者 SEDAGHATZADEH Mostafa SHAHBAZI Khalil +1 位作者 POURAFSHARY Peyman RAZAVI Seyed Ali 《Petroleum Exploration and Development》 2019年第4期826-832,共7页
The effects of different cation concentrations and types on rheological property and stability of Guar, Xanthan, and Partially Hydrolyzed Polyacrylamide(HPAM) cross-linked gels were analyzed through experiments. Also,... The effects of different cation concentrations and types on rheological property and stability of Guar, Xanthan, and Partially Hydrolyzed Polyacrylamide(HPAM) cross-linked gels were analyzed through experiments. Also, a new approach was developed to reduce the negative effects of cation by application of multi-walled carbon nano-tubes(MWCNTs). The presence of cations in cross-linked gel system will reduce the viscosity of gel, the higher the cation concentration is, the lower the viscosity will be. The bivalent cation has a greater viscosity reduction effect on gel than monovalent cation. The stability of cross-linked gels is worse with cations, this situation becomes more serious under higher salinity. MWCNTs were added to HPAM gel, cross-linked by(3-Aminopropyl) triethoxysilane(APTES), they surrounded cations and removed them from polymers and reduced the reaction possibility. This method enhances the viscosity and breakdown pressure of cross-linked gels, improves the stability of HPAM cross-linked gel under different operating conditions, and can be applied to related drilling projects. 展开更多
关键词 cross-linked polymer GEL system RHEOLOGICAL property stability cation multi-walled carbon nano-tubes
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A NEW METHOD TO SYNTHESIZE THE CATIONIC GRAFT STARCH
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作者 LinLi BingyueLiu YafengCao 《天津科技大学学报》 CAS 2004年第A01期220-224,共5页
The cationic graft copolymer was synthesized by reversed phase emulsion copolymerization of starch with diallydimethyl ammoniumlchlorid (DADMAC) and acrylamide(AM). The copolymerization was carried out using (NH4)2S2O... The cationic graft copolymer was synthesized by reversed phase emulsion copolymerization of starch with diallydimethyl ammoniumlchlorid (DADMAC) and acrylamide(AM). The copolymerization was carried out using (NH4)2S2O8-NH2CONH2 redox as initiator and selecting Span-20 as emulsifier. The effects of emulsifier content in oil phase, volume ratio of oil to water, initiator concentration and mole ratio of DADMAC to AM on the graft copolymerization were discussed. The optimum condition of synthetics was found with the orthogonal test method. 展开更多
关键词 接枝共聚物 阳离子淀粉 倒相乳胶 丙烯酰胺 粘性
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STDUY ON RETENTION AND DRAINAGE PROPERTIES OF THE HIGH SUBSTITUTED DEGREE CATIONIC STARCH
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作者 QijieChen FushanChen GaoshengWang HuirenHu 《天津科技大学学报》 CAS 2004年第A01期189-192,共4页
This paper deals with the retention and drainage properties of the high substituted degree cationic starch (HCS) prepared by half-dry process. The experiments show that HCS has remarkable effects on filler retention a... This paper deals with the retention and drainage properties of the high substituted degree cationic starch (HCS) prepared by half-dry process. The experiments show that HCS has remarkable effects on filler retention and drainage in papermaking industry. With the degree of substitution (DS) of HCS increasing, the effects on filler retention and drainage increase. When the DS of HCS is 0.509 and the dosage is 0.08%, the freeness decreases about 12oSR and the filler retention is 79.82%. 展开更多
关键词 阳离子淀粉 保持力 排水性 高取代度 半干燥处理 造纸工业
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APPLICATION OF CATIONIC STARCH BY DRY-PROCESS AS ANIONIC CHARGE NEUTRALIZING AGENTS TO IMPROVE FILLER RETENTION
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作者 FushanChen QijieChen GaoshengWang 《天津科技大学学报》 CAS 2004年第A01期185-188,共4页
This paper deals with the preparation of cationic starch with high degree of substitute by dry-process. The corn starch and the alkali catalyst are mixed in the mixer, then added the cationic etherifying agent (3-chlo... This paper deals with the preparation of cationic starch with high degree of substitute by dry-process. The corn starch and the alkali catalyst are mixed in the mixer, then added the cationic etherifying agent (3-chloro-2-hydroxypropyltrimethylammonium chloride). The reacting time is for 5 hours at the temperature of 70℃. The cationic starch with high degree of substitution is used as anionic charge neutralizing agents to improve filler retention in wet-end section of papermaking machine. 展开更多
关键词 阳离子淀粉 干燥处理 阴离子负荷中和 填料保持 碱性催化剂 醚化剂 取代高度 造纸工业
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Cross-linkedα-amylase aggregates on Fe3O4 magnetic nanoparticles modified with polydopamine/polyethyleneimine for efficient hydrolysis of starch
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作者 Jiandong Cui Xiuming Tang +3 位作者 Qingqing Ma Yuyan Chang Qunli Zhang Shiru Jia 《Particuology》 SCIE EI CAS CSCD 2024年第7期98-105,共8页
In this workα-amylase was immobilized on magnetic Fe3O4 nanoparticles with polyethylenimine(PEI)/polydopamine(PDA)coating or 3-aminopropyl triethoxysilane(APTES)for the first time via adsorption–precipitation–cross... In this workα-amylase was immobilized on magnetic Fe3O4 nanoparticles with polyethylenimine(PEI)/polydopamine(PDA)coating or 3-aminopropyl triethoxysilane(APTES)for the first time via adsorption–precipitation–cross-linking.Compared with the freeα-amylase,the resultant magnetic cross-linkedα-amylase aggregates(PEI/PDA-M-CLEAs and N-M-CLEAs)exhibited excellent thermal and storage stability as well as pH stability.After storage at 25°C for 60 days,freeα-amylase only retained 60%of its initial activity,while PEI/PDA-M-CLEAs and N-M-CLEAs retained 80%and 78%of their initial activities,respectively.Furthermore,N-M-CLEAs and PEI/PDA-M-CLEAs showed good reusability.After 6 repeated uses,PEI/PDA-M-CLEAs and N-M-CLEAs still maintained 65%and 62%of their initial activities,respectively.Especially,PEI/PDA-M-CLEAs and N-M-CLEAs exhibited higher starch hydrolysis efficiency than freeα-amylase.The maximum dextrose equivalent(DE)values of starch hydrolysis by PEI/PDA-M-CLEAs and N-M-CLEAs reached 29.24%and 28.79%within 90 min,respectively.However,the maximum DE values of starch hydrolysis by the freeα-amylase was only 27.89%even in 150 min.The magnetic cross-linkedα-amylase aggregates could be introduced as effective biocatalyst for industrial applications in production of maltose syrups. 展开更多
关键词 Α-AMYLASE Magnetic nanoparticles Functional modification Magnetic cross-linked enzyme aggregates Hydrolysis of starch
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Study on Various Compositions of Polyvinyl Alcohol and Starch Blends by Cross-Linking with Glyoxal 被引量:3
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作者 Ravindra V. Gadhave Prakash A. Mahanwar Pradeep T. Gadekar 《Open Journal of Polymer Chemistry》 2019年第4期76-85,共10页
The aim of this study is to analyze the various compositions of polyvinyl alcohol (PVA) and starch blends. The blends have been cross-linked with glyoxal to enhance its properties. The hydroxyl groups of PVA and starc... The aim of this study is to analyze the various compositions of polyvinyl alcohol (PVA) and starch blends. The blends have been cross-linked with glyoxal to enhance its properties. The hydroxyl groups of PVA and starch react with glyoxal via formation of acetal bonds;hence crosslinking could take place. The cross-linking of glyoxal is observed in various analytical methods such as DSC and FTIR. The cross-linked blends showed better thermal and mechanical properties. Viscosity, tensile shear strength, pencil hardness and ultimate stress were evaluated to estimate the changes due to cross-linking. It was observed that the cross-linking is directly proportional to starch, since the starch hydroxyl groups are easily accessible for reacting. The cross-linked blend showed better cohesion between its chains, thereby increasing glass transition temperature. It was reflected in the subsequent increase in tensile strength properties. 展开更多
关键词 starch Polyvinyl ALCOHOL cross-linking GLYOXAL Mechanical Testing
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Reinforcing Paper Strength by Dual Treatment of a Cationic Water-soluble Polymer and Cellulose Nanofibril 被引量:7
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作者 Aijiao Wang Lijun Wang +2 位作者 Jianmei Jiang Xianping Yao Wenyan Zhao 《Paper And Biomaterials》 2019年第4期31-36,共6页
Cellulose nanofibril(CNF)was used as the anionic component of two dual strengthening systems wherein polyamidopolyamine epichlorohydrin resin(PAE)or cationic starch(CS)was used as the cationic component.Their strength... Cellulose nanofibril(CNF)was used as the anionic component of two dual strengthening systems wherein polyamidopolyamine epichlorohydrin resin(PAE)or cationic starch(CS)was used as the cationic component.Their strengthening effects were investigated for lowbasis-weight(30 g/m2)paper composed of a mixture of fully bleached softwood and hardwood pulp in a 4:1 mass ratio.Using the PAE/CNF or CS/CNF dual system,it was generally easier to achieve higher wet and dry tensile strengths of paper compared to the paper using the single PAE or CS system.For example,the paper using the PAE(0.4%)/CNF(0.3%)dual system exhibited 89%higher wet tensile strength than the paper using the single PAE(0.4%)system,and the paper using CS(1.3%)/CNF(0.3%)dual treatment showed 21%higher dry strength than that using the single CS(1.3%)system.However,the PAE/CNF system only showed small improvement in the dry strength of paper(11%higher than that of paper using the single PAE system),so did the CS/NFC system on wet strength improvement(only 17%higher than that of paper using the single CS system). 展开更多
关键词 CELLULOSE nanofibril polyamidopolyamine EPICHLOROHYDRIN cationic starch DUAL TREATMENT
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高取代度阳离子淀粉基苯丙乳液的合成和应用研究
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作者 刘毅 王立军 +4 位作者 付文晖 贾定 赖亦凡 MARTIN Ekman TOM Schauman 《中国造纸》 CAS 北大核心 2024年第9期94-102,114,共10页
以苯乙烯(St)、丙烯酸正丁酯(BA)、丙烯酸叔丁酯(tBA)为单体,H2O2-FeSO4为引发体系,高取代度阳离子淀粉(HCS)为乳化剂,开展了苯丙表面施胶剂的无皂乳液聚合。探讨了HCS的用量、分子量(以特性黏度表示)、取代度对乳液聚合的影响,使用多... 以苯乙烯(St)、丙烯酸正丁酯(BA)、丙烯酸叔丁酯(tBA)为单体,H2O2-FeSO4为引发体系,高取代度阳离子淀粉(HCS)为乳化剂,开展了苯丙表面施胶剂的无皂乳液聚合。探讨了HCS的用量、分子量(以特性黏度表示)、取代度对乳液聚合的影响,使用多种方法评价了乳液的理化性能与应用性能。所制备得的高取代度阳离子淀粉基苯丙乳液胶粒平均粒径小(126.2 nm)、正电性强(Zeta电位为25.8 mV)、贮存稳定性优良;将其应用在瓦楞原纸上,施胶纸张的Cobb值为21.6 g/m^(2),水滴接触角达121.6°,与低取代度阳离子淀粉基苯丙乳液相比,其应用效果具有明显优势。研究对其能赋予纸张更佳施胶效果的原因也提出了机理性的解释。 展开更多
关键词 阳离子表面施胶剂 苯丙乳液 无皂聚合 高取代度阳离子淀粉
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阳离子淀粉改性阳离子乳液聚合物及其絮凝性能研究
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作者 杨开吉 李志元 +2 位作者 李湘山 张喆 王志远 《造纸科学与技术》 2024年第6期11-16,共6页
通过阳离子淀粉对阳离子乳液聚合物功能化改性,研究阳离子淀粉功能改性对阳离子乳液聚合物性能的影响,得到改性阳离子乳液聚合物絮凝剂对再生纸废水和含油污水进行絮凝性能。结果显示,CS投加量为6%,改性阳离子乳液聚合物絮凝剂用量为28 ... 通过阳离子淀粉对阳离子乳液聚合物功能化改性,研究阳离子淀粉功能改性对阳离子乳液聚合物性能的影响,得到改性阳离子乳液聚合物絮凝剂对再生纸废水和含油污水进行絮凝性能。结果显示,CS投加量为6%,改性阳离子乳液聚合物絮凝剂用量为28 mg/L时,再生纸废水COD去除率达95%,SS去除率达94%;CS改性阳离子乳液聚合物絮凝剂添加量为6 mg/L时,含油污水脱油率为97.78%;并用红外光谱、核磁共振、热重分析和电子显微镜对改性后的阳离子乳液聚合物絮凝剂结构进行了表征,得出阳离子淀粉改性阳离子乳液聚合物性能突出。 展开更多
关键词 阳离子淀粉 阳离子乳液聚合物 功能化改性 絮凝性能
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Starch-Based Adhesives for Wood/Wood Composite Bonding: Review 被引量:6
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作者 Ravindra V. Gadhave Prakash A. Mahanwar Pradeep T. Gadekar 《Open Journal of Polymer Chemistry》 2017年第2期19-32,共14页
Increasing global energy crisis and scarcity of petroleum resources has shifted focus of chemical industries to look for alternative raw material resources. The main focus of raw materials in wood adhesives, such as p... Increasing global energy crisis and scarcity of petroleum resources has shifted focus of chemical industries to look for alternative raw material resources. The main focus of raw materials in wood adhesives, such as petroleum and natural gas [1] [2], would be gradually replaced by renewable biopolymers. Starch is a relatively inexpensive and renewable product from abundant plants, easy processing and it has been extensively used as binders, sizing materials, glues and pastes [3], but its bonding capacity is not strong enough to glue wood [4]. Extensive research has been carried out on improving the cohesive properties, especially water resistance, of starch-based adhesives. In starch-based wood adhesive many new approaches have come forward for effective use it in wood/wood composite adhesive giving comparable performance as synthetic adhesives. This review of starch-based adhesives is made with the focus on starch modification methods for improving properties of starch-based adhesives. 展开更多
关键词 Bio-Polymer starch WOOD Adhesives cross-linking Composite
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Heterogeneous Reactions between Starch and AKD under Solvent-free Conditions 被引量:1
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作者 ShanShan Gao XiaoMing Song +3 位作者 FuShan Chen LianQing Huang JunXun Li SongLin Wang 《Paper And Biomaterials》 2016年第2期27-31,共5页
Oxidized starch powder and cationic starch solution were reacted with alkyl ketene dimer(AKD) under heterogeneous conditions at 70℃ for 12 h.The AKD molecules reacted with starch hydroxyl groups to form β-keto ester... Oxidized starch powder and cationic starch solution were reacted with alkyl ketene dimer(AKD) under heterogeneous conditions at 70℃ for 12 h.The AKD molecules reacted with starch hydroxyl groups to form β-keto ester linkages under the above conditions.The reaction products were separated into CHCl_3-soluble and CHCl_3-insoluble fractions.FT-IR spectroscopy,SEM,Xray diffraction,and TG-DTA analyses of the CHCl_3-insoluble fraction indicated that β-keto ester substituents were introduced to hydroxyl groups on the starch surfaces.The results indicated that hydrogen bonds between the starch molecules were disrupted under heterogeneous conditions upon heating.The activity and accessibility of hydroxyl groups were enhanced,as a result of which β-keto ester bonds were produced between AKD and starch.Based on these results,we speculate that the β-keto esters which existed in the sheets sized by AKD emulsions were generated by the reaction between AKD and starch. 展开更多
关键词 AKD cationic starch oxidized starch heterogeneous reaction sizing agent
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体外透皮递送SPE的CMC/CS/Ca^(2+)复合水凝胶及其抗氧化活性研究 被引量:1
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作者 叶君 刘禄莹 +1 位作者 黄卓生 熊犍 《华南理工大学学报(自然科学版)》 EI CAS CSCD 北大核心 2023年第1期51-60,共10页
像大豆肽(SPE)这样的肽类物质在药物靶向治疗和诊断等方面有着重要作用,但它们难以抵抗胃部极低的pH环境以及离子障碍,因此难以通过口服的方式进行递送。透皮递送系统可避免胃液的障碍,将药物递送到血液中。文中通过冻融循环成功制备了... 像大豆肽(SPE)这样的肽类物质在药物靶向治疗和诊断等方面有着重要作用,但它们难以抵抗胃部极低的pH环境以及离子障碍,因此难以通过口服的方式进行递送。透皮递送系统可避免胃液的障碍,将药物递送到血液中。文中通过冻融循环成功制备了负载SPE的羧甲基纤维素/阳离子淀粉/Ca^(2+)(CMC/CS/Ca^(2+))复合水凝胶,以克服透皮递送过程中皮肤角质层对水溶性SPE渗透的障碍。颗粒电荷分析(PCD)、傅里叶变换红外光谱(FT-IR)以及流变结果表明,CMC、CS及Ca^(2+)之间产生了化学和物理交联作用,形成了稳定的复合水凝胶,且SPE与CS、Ca^(2+)间产生的相互作用使其力学性能可满足透皮递送的要求;扫描电子显微镜(SEM)和比表面积测试(BET)结果表明,这些复合水凝胶内部具有多孔洞的三维网络结构。复合水凝胶的含水率均高于95.63%,在25℃下持续25 min后其保湿率仍在97.34%以上,所有复合水凝胶均在120 min内快速溶胀,在720 min时平衡溶胀分数可达636.23%,说明该复合水凝胶对水具有高度的亲和性,这是SPE透皮递送效率提高的根本原因。体外释放结果表明,SPE从复合水凝胶中的释放为溶胀控释型,且其最大DPPH自由基和ABTS自由基清除率分别可达47.07%和72.16%。3种复合水凝胶中SPE的单位面积累积渗透量分别为0.55、0.70和0.60 mg/cm^(2),其累积渗透百分比分别达到84.13%、92.93%和92.57%。复合水凝胶的外观以及pH值、耐热性、耐寒性均符合QB/T 2872—2017的规定。文中制备的复合水凝胶不仅有望在透皮递送肽及蛋白质类药物上得以应用,在皮肤抗氧化护理方面也具有潜在的应用价值。 展开更多
关键词 羧甲基纤维素 阳离子淀粉 大豆肽 透皮递送 抗氧化活性
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阳离子改性淀粉原位除藻试验研究
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作者 罗莎 杨洁 +1 位作者 郝志香 王建波 《海河水利》 2023年第2期122-125,共4页
以阳离子改性淀粉作为絮凝剂,在天津某饮用水源地一蓝藻富集区进行原位处置,对比分析水体在投加淀粉前后pH值、透明度、总氮、总磷、浮游植物丰度及种群结构的变化。结果表明,阳离子改性淀粉能使水体表层藻类迅速絮凝成团下沉,水体透明... 以阳离子改性淀粉作为絮凝剂,在天津某饮用水源地一蓝藻富集区进行原位处置,对比分析水体在投加淀粉前后pH值、透明度、总氮、总磷、浮游植物丰度及种群结构的变化。结果表明,阳离子改性淀粉能使水体表层藻类迅速絮凝成团下沉,水体透明度显著提升,水中氮磷浓度明显降低。与对照区相比,试验区表层浮游植物的丰度显著下降,前6 d浮游植物去除率为86%~95%,整个试验周期平均去除率为78%,其中原优势种铜绿微囊藻下降最为突出,该絮凝剂对球状藻的去除和控制效果优于丝状藻。 展开更多
关键词 阳离子改性淀粉 原位 除藻
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阳离子淀粉的制备及其在污泥调理中的应用
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作者 蒋佳妙 杨帆 +2 位作者 陈家玉 由耀辉 杨柳 《山东化工》 CAS 2023年第7期245-248,共4页
污泥调理是实现污泥高效脱水的重要工序,传统污泥调理剂存在投加剂量高、环境污染大等问题。基于此,本研究选择价廉易得的玉米淀粉为原料,以2,3-环氧丙基三甲基氯化铵为醚化剂,制得阳离子淀粉,而后将其应用于剩余污泥的脱水调理中。结... 污泥调理是实现污泥高效脱水的重要工序,传统污泥调理剂存在投加剂量高、环境污染大等问题。基于此,本研究选择价廉易得的玉米淀粉为原料,以2,3-环氧丙基三甲基氯化铵为醚化剂,制得阳离子淀粉,而后将其应用于剩余污泥的脱水调理中。结果表明,当阳离子淀粉剂量为80 mg/g时,污泥毛细吸水时间(CST)和过滤比阻(SRF)均降到最低值,分别为23.5 s和1.50×10^(12) m/kg,此时CST下降85.9%,SRF下降92%。调理后污泥zeta电位值随阳离子淀粉剂量的增加而升高,表明阳离子淀粉与污泥颗粒之间发生了电荷中和作用,电荷的改变使污泥颗粒脱稳,从而形成较大的絮体。对污泥胞外多聚物(EPS)进行分析发现,EPS中的蛋白质组分可与阳离子淀粉发生反应,从而影响污泥脱水性能。综上,阳离子淀粉制备方法安全简便,具有良好的污泥调理效果,在污泥脱水中有着广阔的应用前景。 展开更多
关键词 阳离子淀粉 污泥脱水性能 污泥调理 胞外聚合物
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