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991.
992.
本文研究了GMT湿法成型工艺中PP接枝改性及偶联剂对材料界面及性能的影响,并通过SEM对材料拉伸断口形貌进行了分析。 相似文献
993.
响应面法优化反相乳液聚合制备淀粉接枝丙烯酰胺共聚物 总被引:2,自引:0,他引:2
采用响应面分析法(RSM)中CCD数学模型优化淀粉接枝丙烯酰胺共聚物的工艺参数,考察引发剂浓度、反应温度、单体淀粉质量比对单体转化率Y<,1>与接枝率Y<,2>的影响.实验采用等高线莺叠法获得最佳工艺条件:引发剂浓度3.451 mmoL/L、反应温度50℃、单体淀粉质量比在1.54:1,此条件下,产物单体转化率为93.... 相似文献
994.
Phuthiya Ratanasiriwat Wanchai Worawattanamateekul Wanwimol Klaypradit 《International Journal of Food Science & Technology》2013,48(4):749-757
The encapsulated wasabi flavour prepared from 100% modified starch (HICAP? 100), HICAP? 100: maltodextrin (1:1), HICAP? 100:CAPSUL (1:1) at various flavouring agent concentrations (10, 15 or 20% w/w) was determined for physicochemical properties. All encapsulated treatments were stored at various relative humidity (RH) levels (11%, 33% and 52% RH) and intervally evaluated for encapsulation efficiency (EE) during 60 days of storage. Microcapsules of 20% wasabi flavour derived from the mixture of HICAP? 100 with maltodextrin and HICAP? 100 with CAPSUL demonstrated excellent properties including low moisture content, acceptable flowing properties, surface appearance and EE. The release rate of encapsulated flavour increased as the RH increased for most encapsulated treatments. A difference‐from‐control test was conducted to evaluate the magnitude of wasabi‐flavour retention added in the canned tuna spread. The intensity of wasabi‐flavour retention in the canned tuna spread with encapsulated flavour agents added was higher than that of the samples without flavour encapsulation. 相似文献
995.
A process of plasma‐initiated grafting of acrylic acid on commercial porous polypropylene membrane was studied. The influence of parameters of the plasma (power, gas pressure, time plasma‐sample distance, sample arrangement) and grafting (solvent composition, monomer concentration, time, inhibitor presence) on the degree of grafting, amount of homopolymer produced and surface electrical resistance was determined. A degree of grafting up to 18 mmol/g was obtained, which resulted in sample resistance as low as 30 mΩ cm2. The molecular weight of AAc homopolymer that can be assumed as equal to the MW of grafted chains, ranged from 25,000 to 50,000,000 da. SEM and water permeability measurements show that grafting causes filling of the pores, which, however, does not stop K+ ions from penetrating the membrane. The performance of nickel‐cadmium cells with acrylic acid grafted membranes as separator is also presented. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
996.
A library of thiol‐terminated methacrylate telomers aimed for use in surface modifications of chromatographic support materials has been prepared by iniferter mediated polymerization, using isopropylxanthic disulfide as a photoiniferter. The telomers range from hydrophobic to hydrophilic and were prepared in different lengths, with the length being adjusted by the ratio of monomer to iniferter used in the polymerization mixture. The telomers were characterized by size‐exclusion chromatography and MALDI‐TOF‐MS. In initial surface characterization experiments, the prepared telomers were attached to the inner surface of fused silica capillaries by radical initiated addition to vinyl groups, and the electro‐osmotic flow (EOF) in the prepared capillaries was determined in a capillary electrophoresis set‐up. The EOF measurements verified surface grafting. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
997.
Fang Li Xiangzhen Kong Caimeng Zhang Yufei Hua 《International Journal of Food Science & Technology》2011,46(8):1554-1560
The effect of heat treatment on the properties of soy protein‐stabilised emulsions was investigated. Emulsions were prepared with unheated and heat‐treated soy protein (NSP and HSP) dispersions. Heating on soy protein dispersions at 95 °C for 30 min resulted in smaller average oil droplet size, lower tendency for oil droplet flocculation, higher protein adsorption and lower viscosity. The properties of emulsions were significantly influenced by the protein concentration. The sodium dodecyl sulphate–polyacrylamide gel electrophoresis (SDS–PAGE) profiles showed that the heat treatment on soy protein dispersions increased the protein adsorption at O/W interface. The viscosity of all samples at low shear rate was inversely proportional to the d32, suggesting a positive relation to the total interfacial area per unit volume. Emulsions showed shear‐thinning behaviour. The relaxation time was found to increase with aqueous phase viscosity determined by the Cross viscosity model. 相似文献
998.
The functionalization of styrene‐b‐(ethylene‐co‐1‐butene)‐b‐styrene tri‐block copolymer with maleic anhydride (MAH) in melt state through ultrasound initiation was studied in this article. The effects of plasticizer content and types, MAH content, ultrasound power, and die temperature on grafting ratio of MAH were investigated by means of acid–base titration. Functionalized products were confirmed by new absorption bands in Fourier‐transform infrared spectroscopy. The experimental results showed that the ultrasound initiated products had lower complex viscosity (η*), lower gel content as well as lower molecular weight than peroxide initiated products, indicating that the ultrasound could cause chain scission and suppress the crosslinking side reaction to gain functionalized products, which have less gel content and high grafting ratio. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
999.
Surface modified electrodes are used in electro-analysis, electro-catalysis, sensors, biomedical applications, etc. and could also be used in batteries. The properties of modified electrodes are determined by the surface functionality. Therefore, the steps involved in the surface modification of the electrodes to obtain specific functionality are of prime importance. We illustrate here bridging of two routes of surface modifications namely electrochemical grafting, and chemical or electrochemical reduction. First, by electrochemical grafting an organic moiety is covalently immobilized on the surface. Then, either by chemical or by electrochemical route the terminal functional group of the grafted moiety is transformed. Using the former route we prepared lithium alkyl carbonate (–O(CH2)3OCO2Li) modified carbon with potential applications in batteries, and employing the latter we prepared phenyl hydroxyl amine (–C6H4NHOH) modified carbon which may find application in biosensors. Benzyl alcohol (–C6H4CH2OH) modified carbon was prepared by both chemical as well as electrochemical route. We report combinations of conjugating the two steps of surface modifications and show how the optimal route of terminal functional group modification depends on the chemical nature of the moiety attached to the surface in the electrochemical grafting step. 相似文献
1000.