二次掺杂聚苯胺的SEM研究

化学方法合成聚苯胺，通过氨水解掺杂，得到本征态聚苯胺，再用酒石酸对聚苯胺进行二次掺杂。采用扫描电镜（SEM）研究了苯胺／酒石酸的反应物质的量比、反应时间、反应温度对聚苯胺／酒石酸产物的形貌的影响，并利用红外光谱和紫外光谱对其结构进行了表征。     

酒石酸掺杂微/纳米结构聚苯胺的制备及表征

以酒石酸为掺杂剂,过硫酸铵为氧化剂,采用"无模板"自组装法合成了掺杂态聚苯胺微/纳米纤维。分析了酒石酸与苯胺的不同摩尔比对产物形貌、分子结构及电性能的影响。结果表明,酒石酸与苯胺摩尔比为1时,生成了长径比较大、有序性较好的聚苯胺微/纳米纤维,该比例下电导率达到9.355×10-2 S/cm。改变反应温度和反应时间,酒石酸在常温下自组装掺杂即可得到较高电导率的聚苯胺产物。傅里叶变换红外光谱、紫外可见光分光光度计、X射线衍射仪的表征结果证明,不同酒石酸与苯胺摩尔比下合成的聚苯胺微/纳米纤维均为掺杂态,且具有一定的导电性。     

单宁酸二次掺杂聚苯胺纳米材料的制备及防腐性能

采用直接混合法,在酒石酸体系下合成一次掺杂聚苯胺纳米材料,经氨水解掺杂后,再用单宁酸对其进行二次掺杂制备出单宁酸二次掺杂聚苯胺材料,解决了单宁酸体系下苯胺无法有效聚合制备聚苯胺的难题。通过扫描电镜、红外光谱及紫外光谱测试对产物进行了表征,利用电化学工作站测试了不同聚苯胺薄膜对Q235碳钢的防腐蚀性能。结果表明,通过二次掺杂方法,单宁酸能有效地掺杂到聚苯胺中,获得形貌良好的纳米纤维;单宁酸二次掺杂聚苯胺能较长时间有效地保护金属基材,其防腐蚀效率最高可达86.02%,在天然海水中浸泡7 d后仍能保持在78.84%。     

酸掺杂聚苯胺合成及性能研究

采用微乳液聚合法,以十二烷基磺酸钠为乳化剂、过硫酸铵为引发剂、盐酸为质子掺杂酸、苯胺为原料制得酸掺杂聚苯胺。运用傅里叶变换红外光谱仪对聚苯胺的结构进行表征,探究浓盐酸掺杂量对聚苯胺电导率的影响,以及聚苯胺流变性能和热分解动力学研究。结果表明,掺杂酸量对电导率有明显影响,当浓盐酸掺杂量为6.5mL时,聚苯胺具有良好的电导率,平均电导率为1.360S/cm;聚苯胺的热分解反应平均活化能为93.66kJ/mol。     

聚苯胺的合成优化及其电化学性能研究

运用正交试验法研究了温度、酸浓度、氧化剂配比、金属离子掺杂对乳液聚合聚苯胺性能的影响,结果表明,反应最佳条件为NH4S2O8(m=1.5g):An=3:5、HCl浓度1.2mol/L、反应温度20℃、掺杂离子为Fe3+。不同条件下合成的掺杂态聚苯胺经红外、电导率测定以及循环性能测试,证明,掺杂聚苯胺具有较好的电化学性能。     

磺基水杨酸掺杂聚苯胺的气敏性能

采用化学氧化聚合法分别在磺基水杨酸和盐酸中合成了聚苯胺,并用FT-IR和TG-DTA技术对聚苯胺掺杂前后的结构变化和热稳定性进行了分析。研究了不同质子酸掺杂对聚苯胺气敏性能的影响,结果表明,磺基水杨酸掺杂的聚苯胺不仅比普通盐酸掺杂的聚苯胺具有更好的环境稳定性,而且对目标气体具有更好的灵敏性,在室温下对10-3L/L NH3的灵敏度达到了15.47。     

基于聚(2-丙烯酰胺基-2-甲基丙磺酸)表面活性剂和掺杂剂的聚苯胺中空微球EI北大核心CSCD

采用自组装法分别在表面活性剂2-丙烯酰胺-2-甲基丙磺酸(AMPS)、十二烷基磺酸钠(SDBS)和聚(2-丙烯酰胺基-2-甲基丙磺酸)(PAMPS)水溶液中合成聚苯胺,用扫描电镜、透射电镜和比表面分析仪对不同表面活性剂合成的聚苯胺进行表征;用PAMPS对聚苯胺进行掺杂,采用红外光谱、紫外光谱、X射线光电子能谱等探讨PAMPS对聚苯胺的掺杂效应;通过循环伏安法和电化学阻抗法研究PAMPS掺杂聚苯胺的电化学性能。结果表明,PAMPS能够更好地调控聚苯胺的形貌和提高聚苯胺微球的分散性,以及更好地起到表面活性剂效果;PAMPS掺杂后的聚苯胺的电导率提高到了100S/cm级别,比未掺杂态聚苯胺提高了近104倍,具有更大响应电流,展现出更大的电容量。     

温度对固相聚合反应盐酸掺杂聚苯胺的影响

利用固相聚合反应法制备了盐酸掺杂聚苯胺,并以红外光谱(FT-IR),电子扫描显微镜(SEM)、X射线衍射(XRD)、循环伏安(cyclic voltametry)等测试,对聚苯胺进行了表征。结果表明,固相反应法合成的聚苯胺颗粒要比液相法合成的聚笨胺颗粒相对小,并表现出良好的结晶性,而低温(0℃)固相聚合反应法制备的盐酸掺杂聚苯胺要比室温固相聚合反应法制备的聚苯胺颗粒分布均匀,晶化率好,还具有良好的电导率。循环伏安测试表明,固相反应法合成的聚苯胺有较好的电化学活性。     

界面聚合法合成有机酸掺杂聚苯胺结构与性能研究

以苯胺为单体,过硫酸铵为氧化剂,分别以乙酸、月桂酸、硬脂酸、十二烷基苯磺酸为掺杂酸,通过界面聚合法成功制备了有机酸掺杂聚苯胺,对其导电性能、溶解性能进行评价,对其化学结构、晶型结构和微观结构进行分析。结果表明:当苯胺与掺杂酸摩尔比为1∶2时电导率普遍较好,约为(1.73～2.43)×10-4S/cm;有机酸掺杂聚苯胺在极性溶剂中溶解性较好;FT-IR分析结果证明有机酸对聚苯胺进行了成功掺杂;XRD结果说明聚苯胺在2θ=6°的衍射峰受掺杂酸尺寸影响较大,且对聚苯胺的微观形貌具有显著影响。     

二次掺杂聚苯胺的合成及其导电性能的研究

掺杂态的聚苯胺(PANI)合成是采用快速直接法合成盐酸/PANI,用氨水水解掺杂态,得到本征态PANI,再用对甲苯磺酸对PANI进行二次掺杂。在不同反应摩尔比、不同反应时间、不同反应温度下合成的对甲苯磺酸/PANI,用于测量电导率,得出优化条件。采用透射电镜(TEM)观察其形貌,并利用红外光谱和紫外光谱对其结构进行了表征。     

Interfacial interaction of tartaric acid with hydroxyapatite and enamel

The purpose of this study was to investigate the interfacial interaction of tartaric acid with hydroxyapatite and enamel. Hydroxyapatite particles were mixed with 15% (w/v) alcohol-aqueous (1:1) solution of tartaric acid for 72 h. After the mixture, the filtrate was separated from the solid. The filtrate, the solid, hydroxyapatite, and tartaric acid were dried for FTIR and XRD analysis. Enamel disks etched with tartaric acid for 60 s were analyzed by attenuated total reflectance (ATR). Enamel disks etched with 15% tartaric acid for 15, 30, 60, 120 s were analyzed by SEM. FTIR spectra showed carboxylate in the solid and in subtraction spectra. ATR spectra revealed carboxylate on the enamel surfaces. XRD data indicated the formation of calcium tartrate and calcium hydrogen phosphate after the reaction of tartaric acid with hydroxyapatite. SEM observations revealed typical decalcification of the periphery of the enamel rods due tartaric acid etching. It is concluded that tartaric acid can decalcify and chemisorb onto HA simultaneously, hence, tartaric acid could be used as etchant and ingredient of self-etching primers in adhesive dentistry.     

酞菁铜羧酸掺杂聚苯胺薄膜制备表征及光电性研究

成功制备了酞菁铜羧酸掺杂聚苯胺(PANI)薄膜.红外光谱测试结果说明酞菁铜羧酸的羧基和聚苯胺的氨基发生了酸碱中和反应,即成功的对聚苯胺进行了掺杂.紫外可见光谱说明酞菁铜羧酸掺杂后PANI在紫外区有强吸收峰,在可见光区吸收变宽.光电性能测试结果表明掺杂后酞菁铜使聚苯胺对光的敏感性增强,更容易受光子的激发,因而具有更优越的光电性.     

甲磺酸掺杂聚苯胺的制备和表征

在低温和室温条件下制备了本征态聚苯胺,采用超声波分散制备了本征态聚苯胺薄膜,用甲磺酸掺杂制备了聚苯胺导电薄膜。用紫外光谱、红外光谱表征了聚苯胺的化学结构;用X光电子能谱分析了薄膜表面主要元素含量和化学态,得到薄膜掺杂率[SO3-]/[N]为0.57左右,在一定范围内,几乎不受聚苯胺分子量的影响。     

Polyaniline as a Gas-Sensor Material

Polyaniline (PANI) was synthesized by oxidative polymerization of aniline using ammonium persulfate in an acid medium. The polyaniline salt was converted to base form by treatment with ammonium hydroxide. The polyaniline base was dissolved in N-methyl pyrrolidone (NMP) for film casting. The cast film was doped with HCl for obtaining higher conductivity. Both doped and undoped PANI films were characterized by UV-visible, FTIR, and XRD analyses. The electrical conductivity of the PANI film was studied by a four-point probe method at room temperature. Finally, ammonia gas-sensing characteristics of the prepared polyaniline film were studied by measuring the change in electrical conductivity on exposure to ammonia gas at different concentrations. The influence of concentration of acid during polymerization of aniline and dopant concentration on the gas sensing characteristics of PANI film are reported in this paper.     

手性聚苯胺的制备及其电磁学性能研究

采用二次掺杂法制备了具有手征特性的聚苯胺,利用傅立叶红外光谱(FT-IR)、X射线衍射仪(XRD)、圆二色谱仪(CD)和紫外一可见光分光光度计(UV-vis)等分析手段对聚苯胺的结构、性能和手征特性进行了表征.结果表明,通过过硫酸铵作引发剂、盐酸掺杂获得了导电的盐酸掺杂态聚苯胺(PANI-HCI);通过氨水脱掺杂后得到本征态聚苯胺(EB),EB通过手性樟脑磺酸(CSA)诱导,形成了手征性螺旋构型聚苯胺.电磁性能测试表明,与非手性聚苯胺相比,手性聚苯胺具有较优越的吸波性能.     

Influence of dielectric constant of polymerization medium on processability and ammonia gas sensing properties of polyaniline

Polyaniline (PANI) was synthesized by the oxidation of aniline hydrochloride in the presence of ammonium persulphate and hydrochloric acid. The polymerization reaction was carried out in several batches in different solvent media by changing the volume ratio of N,N -dimethyl formamide (DMF) and water as binary solvent mixture. The dielectric constant of the polymerization medium for each batch reaction was determined by measuring the capacitance with change in frequency. The UV spectra of the synthesized polyaniline solutions helped us to optimize the ratio of the binary solvent to get sufficient polymer growth and processability. Thin film of processable polyaniline was then deposited on glass slides coated with polyvinyl alcohol (PVA) crosslinked with maleic anhydride (MA). FTIR and XRD studies of the coated film were also done. AFM studies further helped in the morphological study of the film deposited. Finally, conductivity and ammonia gas-sensing property of the polyaniline film were also studied.     

Reduction of Np(VI) and Pu(VI) with anions of some substituted carboxylic acids

The reaction of Np(VI) with organic acid anions in solutions containing lithium salts of tartaric, malic, α-aminoglutaric, and trihydroxyglutaric acids was studied. Changes in the solution spectra show that Np(VI) forms complexes with organic acid anions, which is followed by the reduction of Np(VI) to Np(V). Similar processes occur in solutions containing Pu(VI) and sodium phenylglycolate or ammonium salicylate. In weakly acidic solutions, the loss of the Np(VI) and Pu(VI) concentrations is a linear function of time. The possible mechanism of the redox reactions was suggested.