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采用双肼基硫代乙二胺分别与HPMBP、对二甲氨基苯甲醛、香草醛、间硝基苯甲醛、对羟基苯甲醛、苯甲醛双缩合成了相应的双Schiff碱。利用元素分析法,红外光谱法,核磁共振对其进行了表征。 相似文献
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采用球磨、气流粉碎和喷雾干燥等物理方法对麦草碱木质素分别进行预处理,制备不同结构特征的木质素颗粒。结果表明,气流粉碎木质素的平均粒径最小,为3.01μm,其次为球磨木质素和喷雾干燥木质素,平均粒径分别为16.02μm和27.23μm。气流粉碎木质素的比表面积最大,达到21.87 m2/g,球磨和喷雾干燥木质素的比表面积分别为2.61 m2/g和1.90m2/g。将3种预处理方法制备的木质素颗粒分别与低密度聚乙烯(LDPE)熔融共混制备木质素/LDPE复合材料,结果表明,在木质素质量分数相同时,采用喷雾干燥木质素制备的复合材料的拉伸强度比气流粉碎木质素大0.4MPa,比球磨木质素大1.5MPa。微观结构分析表明,喷雾干燥木质素在LDPE中分散最均匀,与LDPE相之间的结合力较好。 相似文献
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《高分子材料科学与工程》2020,(2)
首先以异佛尔酮二异氰酸酯(IPDI)、聚四氢呋喃(PTMG)和2,4-二羟基苯甲醛(DBA)为原料制备了水性聚氨酯(DBA-WPU),再以此为交联剂,通过其分子链上的醛基与废弃皮革中提取的工业明胶(INGE)的氨基发生Schiff碱交联反应制得木材胶黏剂INGE/DBA-WPU。紫外光谱(UV-vis)、傅里叶变换红外光谱(FT-IR)和核磁分析(~1H-NMR)表明成功地将DBA引入到水性聚氨酯分子主链上,利用DBA分子链上的羟基与聚氨酯预聚体上的异氰酸酯基反应制备DBA-WPU交联剂。通过FT-IR、X射线衍射(XRD)、接触角、热重分析(TGA)和湿剪切强度对INGE/DBA-WPU黏合剂进行性能检测和结构表征。结果表明,DBA-WPU与INGE发生交联反应,使得胶黏剂的接触角和热稳定性提高。应用试验结果表明,当DBA-WPU用量为30%时,胶黏剂的湿剪切强度高达1.1 MPa,满足GB/T 9846.3-2004中Ⅱ类胶合板的使用要求(≥0.7 MPa),表明引入DBA-WPU可以提高INGE木材黏合剂的耐水性。 相似文献
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以氯化铜、磷酸二氢钠和尿素为原料, 加入模板剂十二烷基硫酸钠(SDS), 采用微波辅助加热法制备了具有不同规则结构的晶态羟基磷酸铜。实验研究了CuCl2与NaH2PO4的摩尔比、模板剂种类和原料浓度等因素对合成羟基磷酸铜晶体的影响。产物采用XRD、SEM和Raman等进行表征, 并通过降解甲基蓝溶液(MB)测试了羟基磷酸铜的催化性能, 探讨了制备条件对产物光催化降解性能的影响。结果表明, 当n(Cu)/n(P)为2, [PO43-]= 0.0025 mol/L, 微波加热温度80℃, 反应时间30 min, 尿素用量6.0 g, SDS用量为0.10 g时制备的羟基磷酸铜具有良好的光催化效果。实验还测试了催化剂的表面光电压谱, 并使用苯甲酸作为荧光探针, 叔丁醇为羟基自由基捕获剂初步验证了光催化反应中羟基磷酸铜的催化机理。 相似文献
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聚苯胺及苯胺共聚物的合成与表征 总被引:9,自引:0,他引:9
用化学氧化法制备了本征态、掺杂态聚苯胺,苯胺与邻氨基苯甲酸共聚物,聚邻氨基苯甲酸均聚物,苯胺与邻氨基苯磺酸共聚物,以及以还原态聚苯胺为原料制备了磺化聚苯胺。并用红外、紫外光谱对它们的结构与性质进行了表征。此外,还比较了它们的溶解性、成膜性和热稳定性。 相似文献
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壳聚糖(CTS)经氨基保护合成席夫碱,再与由对氨基苯甲酸和氯化亚砜制备的对氨基苯甲酰氯反应,产物在一定pH下氨基去保护得到了对氨基苯甲酸壳聚糖酯(ABCTSE)。产物经FT-IR、1H NMR、13C NMR进行结构表征,证实为目标产物;由元素分析得到所制得壳聚糖酯的酯化度为16.8%、40.4%;室温下,壳聚糖衍生物在蒸馏水及有机试剂中的溶解性比壳聚糖更好;产物的TG和DTG分析结果表明所制得壳聚糖酯的稳定性稍低于壳聚糖。另外,由于分子结构中两个氨基的存在,其溶于弱酸性溶液后随着形成—NH3+的增多,使其在抑菌方面有更大优势。 相似文献
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Poly p-aminobenzoic acid has been synthesized by chemical oxidation method. The inhibitive effect of poly p-aminobenzoic acid on iron in 1 mol/L HCl solution was investigated by polarization and electrochemical impedance spectroscopy and compared with that of monomer p-aminobenzoic acid. The effectiveness of poly p-aminobenzoic acid is very high in comparison with that of monomer. The results show that both cathodic and anodic processes were suppressed by p-aminobenzoic acid and poly p-aminobenzoic acid of iron dissolution in 1 mol/L HCI by their adsorption on the iron surface. The inhibition efficiency of both p-aminobenzoic acid and poly p-aminobenzoic acid were found to increase with the inhibitor concentrations. Ultraviolet (UV) reflectance studies of the iron surface after exposure to inhibitor acid show that poly p-aminobenzoic acid is strongly adsorbed on iron surface. 相似文献
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We demonstrated an acetalization reaction as a versatile method to immobilize aromatic aldehyde molecules on surfaces of metal oxides, silicon dioxide, and indium tin oxide. First, a trimethylsily (TMS) terminated surface was formed using a silylation reaction between a chloride group of trimethylsilychloride and a hydroxyl group of the substrate surfaces. Second, terephthalaldehyde (TPA) was immobilized on the surfaces using an acetalization reaction between the TMS-terminated surface and an aldehyde group of TPA. Results of contact angle, X-ray photoelectron, and ultraviolet absorption spectra revealed that the TPA molecules on the surfaces were well-packed with a high surface density. 相似文献
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P.Maniyel G. Venkatachari 《材料科学技术学报》2006,22(3):301-305
Poly p-aminobenzoic acid has been synthesized by chemical oxidation method. The inhibitive effect of poly p-aminobenzoic acid on iron in 1 mol/L HCI solution was investigated by polarization and electrochemical impedance spectroscopy and compared with that of monomer p-aminobenzoic acid. The effectiveness of poly p-aminobenzoic acid is very high in comparison with that of monomer. The results show that both cathodic and anodic processes were suppressed by p-aminobenzoic acid and poly p-aminobenzoic acid of iron dissolution in 1 mol/L HCI by their adsorption on the iron surface. The inhibition efficiency of both p-aminobenzoic acid and poly p-aminobenzoic acid were found to increase with the inhibitor concentrations. Ultraviolet (UV) reflectance studies of the iron surface after exposure to inhibitor acid show that poly p-aminobenzoic acid is strongly adsorbed on iron surface. 相似文献
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Yu Wu Liu Yuan Nai-an Sheng Zi-qi Gu Wen-hao Feng Hai-yue Yin Yosry Morsi Xiu-mei Mo 《材料科学前沿(英文版)》2017,11(3):215-222
Sodium alginate and carboxymethyl chitosan have been extensively applied in tissue engineering and other relative fields due to their low price and excellent biocompatibility. In this paper, we oxidized sodium alginate with sodium periodate to convert 1,2-hydroxyl groups into aldehyde groups to get aldehyde-sodium alginate (ASA). Carboxymethyl chitosan was modified with ethylenediamine (ED) in the presence of water-soluble N-(3-Dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride (EDC) to introduce additional amino groups to get amino-carboxymethyl chitosan (A-CS). Upon mixing the A-SA and A-CS aqueous solutions together, a gel rapidly formed based on the Schiff’s base reaction between aldehyde groups in A-SA and amino groups in A-CS. FTIR analysis confirmed the characteristic peak of Schiff’s base group in the hydrogel. It was confirmed that the gelation time be dependent on the aldehyde group content in A-SA and amino group content in A-CS. The fasted hydrogel formation takes place within 10 min. The data of bonding strength and cytotoxicity measurement also showed that the hydrogel had good adhesion and biocompatibility. All these results support that this gel has the potential as soft tissue adhesive. 相似文献
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以玉米淀粉为原料,盐酸为酸解剂,高碘酸钠为氧化剂,采用一步酸解氧化法合成双醛淀粉,经傅里叶变换红外光谱仪表征证明成功制得了双醛淀粉。研究了反应温度、反应时间、盐酸浓度和淀粉乳浓度对双醛淀粉醛基含量的影响,并利用X射线衍射仪和热重分析仪进行了表征。结果表明,双醛淀粉的醛基含量随着反应温度的升高和反应时间的延长而增大,55℃和4h后,酸解氧化趋于稳定。盐酸浓度和淀粉乳浓度过高会导致双醛淀粉的醛基含量下降,分别以0.6mol/L和8%为宜。X射线衍射仪分析表明,随着盐酸浓度的增加,双醛淀粉的结晶度升高;热重分析仪分析表明,结晶度高的双醛淀粉热分解残余量也更多,而热分解初始温度随着盐酸浓度增加而降低。 相似文献
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用新方法合成膦酸化合物缓蚀剂用于减少金属腐蚀,过去研究得较少.为此,采用芳醛、胺及亚磷酸反应的新方法,即等摩尔的芳醛、胺与亚磷酸在合适的温度下生成亚磷酸盐.升高反应温度至亚磷酸盐的熔点时,其化合物颜色发生变化,继续升高10 ℃, 0.5 h后,撤去热源,经水解后,提纯该物质,即可得到多种氨基烃基膦酸.用元素分析,IR,NMR 对合成的化合物进行表征.目标化合物:(HO)2(O)PC(R1)HNHR2;R1:Ph;o-HO-Ph;2,4-2Cl-Ph;p-No2-Ph;R2:Et;t-C4H9; CH2COOH;Ph;p-Me-Ph;p-Cl-Ph;CH2Ph;m-No2-Ph;β-NaPh;NH2CH2CH3.本方法为一锅法合成,产品可靠,性能好. 相似文献
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Li Z He L He N Deng Y Shi Z Wang H Li S Liu H Wang Z Wang D 《Journal of nanoscience and nanotechnology》2011,11(2):1074-1078
A novel method was established through the detection of chemiluminescent signals of nucleic acid hybridization based on magnetic nanoparticles (MNPs) and PCR. 5' amino- modified specific probes were immobilized on the surface of silanized MNPs by Schiff reaction between amino and aldehyde group. The probes were used to capture the synthetic biotin-dUTP-labeled DNA fragments which were obtained by polymerase chain reaction (PCR). Then these complexes were bonded with streptavidin-modified alkaline phosphatase (SA-AP). Finally the chemiluminescent signals were detected by adding 3-(2'-spiroadamantane)- 4-methoxy -4-(3"-phosphoryloxy) phenyl-1, 2-dioxetane (AMPPD) which was the substrate reagent of AP. The concentration of probes which were immobilized on the surface of MNPs was studied, how to reduce the adsorption of SA-AP on the surface of MNPs was also researched. It was shown that 12.5 pmol of probes were immobilized on 1 mg of MNPs. Aldehyde-MNPs modified with probes could adsorb SA-AP, affecting the sensitivity of chemiluminescene consequently. Reduction of aldehyde group by sodium borohydride and blocking the bare position of MNPs with bovine serum albumin (BSA) could decrease the background of chemiluminescence, and this method has good specificity in detection of chloramphenicol acetyltransferase (CAT) gene. 相似文献