硝酸铈微胶囊对铝合金表面涂层防护性能的影响

将铝合金的缓蚀剂硝酸铈作为囊芯,将脲醛树脂作为囊壁,采用反向乳液聚合的方法合成硝酸铈微胶囊。采用扫描电镜、光学显微镜、红外光谱、热重分析仪对微胶囊进行表征。将合成的微胶囊加入环氧树脂中在铝合金表面制备涂层,并利用电化学阻抗对完好及带划痕的涂层的防护性能进行研究。结果表明:利用反向乳液聚合法可成功合成包覆硝酸铈的微胶囊;添加硝酸铈微胶囊的完好涂层在浸泡1 700 h后的阻抗值在1.5×10~8Ω·cm~2,而环氧清漆及添加硝酸铈涂层的阻抗值均低于10~8Ω·cm~2;带划痕涂层在浸泡288小时后,添加硝酸铈微胶囊的阻抗值为1.9×10~7Ω·cm~2,而环氧清漆及添加硝酸铈涂层的阻抗值分别在1.1×10~7Ω·cm~2、8.6×10~6Ω·cm~2,因此加入硝酸铈微胶囊的涂层比直接加入硝酸铈的涂层及环氧清漆涂层有更优的防腐性能。     

聚(丙烯腈-乙酸乙烯酯)/黄粘土纳米复合材料研究

采用乳液原位插层聚合方法首先创制了聚(丙烯腈-乙酸乙烯酯)/黄粘土纳米复合材料.通过红外光谱(IR),X射线荧光(XRF),X射线衍射(XRD),能谱,扫描电镜(SEM),差热分析(DSC)等方法对该纳米复合材料分析表征,研究结果表明采用单体原位插层聚合法制备纳米复合材料的乳液聚合方法成功制备了直径在纳米级的聚(丙烯腈-乙酸乙烯酯)/黄粘土纳米颗粒.     

PVP对球形铝粉进行表面包覆改性的研究

为防止球形铝粉在空气中腐蚀变质,采用溶液聚合法,通过硅烷偶联剂KH-550对超细铝粉进行预处理,在引发剂偶氮二异丁晴的作用下,用聚乙烯吡咯烷酮(PVP)对球形铝粉进行表面改性,形成了PVP-Al复合粒子。利用扫描电镜、能谱以及红外光谱对改性前后的铝粉进行表征分析;利用光电子能谱对复合粒子的形成原理进行分析。结果表明:复合粒子为具有核-壳结构的球形粒子,致密的PVP壳层包覆铝粒子;复合粒子的沉降率及耐腐蚀性优于原料铝粉。     

面向建筑的石蜡微胶囊制备与表征

以甲基丙烯酸甲酯-丙烯酸甲酯共聚物P(MMA-co-MA)为壁材,以石蜡为芯材,采用乳液聚合法制备了适用于建筑围护结构的相变材料微胶囊(MEPCM)。利用扫描电镜(SEM)、差示扫描量热仪(DSC)、傅里叶红外光谱(FT-IR)、热重分析仪(TGA)、激光粒度分析仪对产品的表面形貌、热物理性能、化学结构、粒径等进行了表征。探讨了十二烷基硫酸钠(SDS)、十二烷基苯磺酸钠(SDBS)、十六烷基三甲基溴化铵(CTMAB)、辛烷基酚聚氧乙烯醚-10(OP-10)对微胶囊形貌的影响。结果表明,以OP-10为乳化剂,芯壳质量比为1.2∶1时,可获得平均粒径为252.17 nm,相变温度为25.12℃,焓值为61.28 J/g,包裹率为71.29%,表面规整均一的球形微胶囊。产物相变温度处于人体舒适范围内,且相变焓值较大,适用于建筑节能。     

聚苯乙烯包覆正十四醇微胶囊的制备及表征EI北大核心CSCD

选用过硫酸钾(K_2S_2O_8)为引发剂,司班80(Span 80)和吐温80(Tween80)为复配乳化剂,聚乙烯吡咯烷酮K30(PVP-K30)为分散剂,季戊四醇四丙烯酸酯(PETA)为交联剂,采用乳液聚合法制备出了以正十四醇(MA)为芯材,聚苯乙烯(PS)为壁材的正十四醇-聚苯乙烯相变微胶囊(MA/PS微胶囊);通过差示扫描量热仪、扫描电镜、傅里叶变换红外光谱仪和热重分析仪等仪器对制备的微胶囊进行检测表征。结果表明,当聚乙烯吡咯烷酮K30和复配乳化剂(m(Span80)∶m(Tween80)=3∶13)加入量分别为正十四醇质量的5%和4%,过硫酸钾和季戊四醇四丙烯酸酯加入量分别为苯乙烯单体质量的10%和37.5%,芯壁比为2.5∶1,搅拌速度为1000r/min时,所制备的MA/PS微胶囊具有良好的热稳定性和致密性。     

无机纳米粒子填充相变微胶囊壁的研究

以纳米T iO2粒子作为填充材料,液体石蜡作为芯材,脲醛树脂作为壁材,采用原位聚合法合成了双层结构的相变微胶囊。采用IR、TG、DTA、SEM、TEM等方法对其结构和性能进行了表征。结果表明,微胶囊壁里引入纳米粒子能有效地起到减少吸水性、提高热稳定性、增加力学强度、改善密封性能的作用,从而提高微胶囊的使用寿命。     

不同性能的双亲性纳米TiO2复合粒子改性聚偏氟乙烯超滤膜结构与性能的研究

利用无皂乳液聚合法合成双亲性聚丙烯酸(PAA)-g-聚甲基丙烯酸甲酯(PMMA)-g-硅烷偶联剂KH570-g-纳米TiO2复合体,通过调节亲水链中丙烯酸(AA)与甲基丙烯酸甲酯(MAA)单体的比例控制复合粒子的表面性能.利用红外光谱、接触角测定、扫描电镜(SEM)等表征技术研究不同表面性能的双亲性纳米TiO2复合粒子...     

PSt/(SiO2-PBA)复合粒子的设计与合成

采用Winzor提出的界面自由能计算方法对核壳型聚苯乙烯／聚丙烯酸丁酯复合粒子的四种常见形态进行了计算,计算结果表明形成正向核壳复合粒子的界面自由能变化最小。定性地分析了硅溶胶粒子吸附在聚苯乙烯乳胶粒表面的可能性。采用种子半连续乳液聚合法制备了聚苯乙烯／(二氧化硅-聚丙烯酸丁酯)复合粒子,利用扫描电镜和透射电镜证实了最终合成的粒子形态,燃烧实验结果表明：该复合乳液具有较好的阻燃性。     

聚苯乙烯包覆正十四醇微胶囊的制备及表征

选用过硫酸钾(K_2S_2O_8)为引发剂,司班80(Span 80)和吐温80(Tween80)为复配乳化剂,聚乙烯吡咯烷酮K30(PVP-K30)为分散剂,季戊四醇四丙烯酸酯(PETA)为交联剂,采用乳液聚合法制备出了以正十四醇(MA)为芯材,聚苯乙烯(PS)为壁材的正十四醇-聚苯乙烯相变微胶囊(MA/PS微胶囊);通过差示扫描量热仪、扫描电镜、傅里叶变换红外光谱仪和热重分析仪等仪器对制备的微胶囊进行检测表征。结果表明,当聚乙烯吡咯烷酮K30和复配乳化剂(m(Span80)∶m(Tween80)=3∶13)加入量分别为正十四醇质量的5%和4%,过硫酸钾和季戊四醇四丙烯酸酯加入量分别为苯乙烯单体质量的10%和37.5%,芯壁比为2.5∶1,搅拌速度为1000r/min时,所制备的MA/PS微胶囊具有良好的热稳定性和致密性。     

乳液聚合法制备TiO2/PS复合粒子及其性能研究

采用乳液聚合法制备了以纳米二氧化钛(TiO2)为核,聚苯乙烯(PS)为壳的复合粒子.利用正交实验研究了引发剂用量、单体用量、表面活性剂浓度对复合粒子包覆效率的影响;通过透光率和亲水亲油实验,检验复合粒子的分散性,并采用透射电镜(TEM),红外光谱(FTIR)表征了复合粒子的形貌和结构.     

Encapsulation of magnetic nanoparticles with polystyrene via emulsifier-free miniemulsion polymerization

Magnetite nanoparticles (Fe₃O₄), with an average size of about 10 nm, were encapsulated with polystyrene using a new method based on emulsifier-free miniemulsion polymerization in the presence of 2, 2′ azobis (2-amidinopropane) dihydrochloride (V-50) as a cationic ionizable water-soluble initiator and hexadecane as a hydrophobe. Transmission electron microscopy (TEM) proved the presence of magnetite in polymer particles which appeared to be monodisperse in size, approximately 100-300 nm in diameter, through TEM and scanning electron microscopy (SEM). Thermogravimetric analysis (TGA) measurement was used to determine the percentage of magnetite in the products. The results of emulsifier-free miniemulsion polymerization were compared with those of conventional emulsifier-free emulsion polymerization using (V-50) as the initiator in both cases.     

海水中钨酸盐复合缓蚀剂对碳钢的缓蚀性能

将海水用于工业可大量节省淡水资源,但海水会对金属设备产生严重腐蚀.采用失重法、极化曲线和表面分析技术就海水中钨酸盐复合缓蚀剂对碳钢(A3)的缓蚀性能及缓蚀机理进行了研究,确定了与钨酸盐具有较好协同效应的缓蚀剂配方.结果表明:单一的钨酸盐对海水中碳钢的缓蚀率随其浓度的增加而增加,浓度低缓蚀率低,40 mg/L以下会加速碳钢腐蚀;四元复合缓蚀剂中钨酸盐、柠檬酸、HEDP和锌盐浓度分别为30,40,10,3 mg/L时,对A3钢的缓蚀率超过93%;单一钨酸盐及其复合缓蚀剂均为阳极型缓蚀剂;添加缓蚀剂后A3钢表面以氧化铁为主要成分,钨与磷也参与了不溶性沉淀膜的形成,有效地抑制了海水对碳钢的腐蚀.     

Preparation of UV-filter encapsulated mesoporous silica with high sunscreen ability

In this study, a UV-filter encapsulated in a mesoporous silica, MCX-MS, was prepared by the in-situ sol-gel polymerization of tetraethyl orthosilicate (TEOS) with an ionic liquid (IL) as solvent and pore-forming agent and octal methoxycinnamate (MCX) as an additive. MCX-MS was characterized by Fourier transformation infrared (FT-IR) spectroscopy and transmission electron microscopy (TEM). The result of the thermogravimetric analysis (TGA) showed that the amount of MCX encapsulated in MS was about 65 wt.% of MCX-MS. Comparing with that of the free MCX, the SPF value of the MCX-MS-containing sunscreen cream increased by about 57%, indicating significant enhancement of the UV protection ability of MCX by encapsulation in the mesoporous silica matrix. Furthermore, because the average particle size of MCX-MS emulsion droplets was big enough, damage by penetration through the skin is expected to be prevented.     

碳钢用绿色复配气相缓蚀剂的制备

目的 制备一种绿色高效复配气相缓蚀剂,用于金属的防锈包装.方法 选用苯甲酸钠(C7H5CO2Na)、葡萄糖酸钠(C6H11O7Na)、植酸(C6H18O24P6)和柠檬酸钠(C6H5Na3O7)为复配药品,以A3钢和45#钢为实验对象.通过密闭挥发减量实验、气相快速甄别实验电化学实验和湿热实验筛选出缓蚀率最高的复配气相缓蚀剂配方.将确定的最高缓蚀率气相缓蚀剂制成气相防锈纸,与防锈原纸、市售气相防锈纸进行防锈效果对照,对照实验采用扫描电子显微镜(SEM)、能谱仪(EDS)和接触角仪测试.结果 筛选出四元复配组11 g/L苯甲酸钠+11 g/L葡萄糖酸钠+15 g/L植酸+5 g/L柠檬酸钠的缓蚀率最高,对A3钢的缓蚀率达到了94.36％,对45#钢的缓蚀率达到了94.47％.经该防锈纸防护的A3钢和45#钢表面光滑,无锈蚀出现,氧元素含量低,且接触角大于90°,呈现明显疏水性.结论 经过4种缓蚀剂药品的复配筛选,最终确定出了缓蚀率最高的气相缓蚀剂配方为11 g/L苯甲酸钠+11 g/L葡萄糖酸钠+15 g/L植酸+5 g/L柠檬酸钠,且制成的复配气相防锈纸防锈效果优于空白组的防锈原纸以及市售气相防锈纸.     

绿色阻垢剂MA/SSS聚合物的表征及其阻垢性能

为丰富绿色水处理剂聚环氧琥珀酸(PESA)的功能性官能团,优化其阻垢性能,以马来酸酐(MA)和苯乙烯磺酸基盐(SSS)为原料,利用固体超强酸SO_4~(2-)/TiO_2-SiO_2为催化剂,熔融聚合了新型含苯乙烯磺酸基聚合物(MA/SSS)。采用红外光谱(FT-IR)和凝胶渗透色谱(GPC)对聚合物进行表征;采用静态试验考察了其CaCO_3阻垢效果,并用扫描电镜(SEM)、能谱仪(EDS)和X射线衍射仪(XRD)测试探讨了MA/SSS的CaCO_3阻垢机理。结果表明:MA/SSS具有羧基、磺酸基和苯环等一系列特征峰,其数均相对分子量Mw为4 174;在相同条件下,与PESA相比,MA/SSS适用于高钙环境且用量小。机理研究表明,MA/SSS干扰或抑制了球霰石进一步结晶生长,形成无定形沉渣。     

二氧化硅消光剂的合成与表征

为了获得性能指标符合消光剂要求的二氧化硅产品,通过正交实验L16(45)对沉淀法合成二氧化硅的过程进行优化,研究各因素对二氧化硅中位径、吸油值的影响规律,利用X射线衍射、扫描电镜对二氧化硅粒子的结构、形貌进行表征。结果表明,制备的二氧化硅为无定形产物,颗粒呈球形,一次颗粒粒径约为30 nm,各项指标与进口产品相近。     

Fumed silica/polymer hybrid nanoparticles prepared by redox-initiated graft polymerization in emulsions

Hybrid particles comprising aggregated fumed silica nanoparticles as the core and hydrophobic polymers existing around the nanoparticles were prepared by ‘grafting from’ polymerization in emulsions. The emulsion polymerization employed cetyltrimethylammonium bromide (CTAB) as a cationic surfactant and sodium dodecyl sulfate (SDS) as an anionic surfactant, respectively, to stabilize the emulsion polymerization. The polymerization was initiated by the redox reaction between ceric ion Ce(IV) and the amine groups on the surfaces of aminated fumed silica nanoparticles that were modified by 3-aminopropyltriethoxysilane. Infrared spectroscopy and thermogravimetric analysis demonstrated that both poly(methyl methacrylate) (PMMA) and polystyrene (PS) were successfully grafted onto the fumed silica surface. The type of surfactant greatly affected the grafting ratio, monomer-to-polymer conversion, and morphology of the product. When CTAB was used as the surfactant, both the grafting ratio and monomer-to-polymer conversion were lower than when SDS was used, but transmission electron microscopy and light scattering analysis indicated that most of the resultant particles were sub-100 nm hybrid nanoparticles with a non-spherical shape and particles sizes of 75–90 and 57–85 nm for PMMA and PS-grafted fumed silica, respectively. Whereas, when SDS was used as the surfactant, the particles agglomerated to form large irregular clusters or even networks, possibly due to the electrostatic attractions between SDS and Ce(IV) and/or the aminated fumed silica nanoparticles in aqueous solution.     

Synthesis of nano-structured lanthanum tungstates photocatalysts

Nano-particles of lanthanum tungstate were prepared through an optimized chemical precipitation reaction using the aqueous solutions of the ingredients. The optimization of the procedure was performed based on performing the so-called Taguchi robust design. The effects of various conditions influencing the size of the produced particles were evaluated using an orthogonal array. The optimally prepared lanthanum tungstate particles were found to be about 31 nm in diameter. The chemical and physical properties of the products were studied through X-ray diffraction, scanning electron microscopy, transmission electron microscopy, FT-IR spectroscopy, UV–Vis and Fluorescence. Also the band gap energy of the produced nanoparticles was assessed through UV–Vis diffuse reflectance spectroscopy. The optimally prepared nano-structures were evaluated as photocatalysts in the pho-degradation of methylene blue.     

微波辐射乳液聚合制备聚氰基丙烯酸正丁酯磁性微球

通过化学共沉淀法制备Fe3O4纳米粒子,再用油酸钠和十二烷基磺酸钠(SDS)对Fe3O4进行改性,制得稳定的水基磁流体。在自制的磁流体存在下,以氰基丙烯酸正丁酯(BCA)为单体,用微波辐射乳液聚合的方法制备了Fe3O4/聚氰基丙烯酸正丁酯磁性微球。并用X射线衍射仪(XRD),透射电子显微镜(TEM),傅立叶红外光谱仪(FT-IR),振动样品磁强计(VSM)对制备的磁性高分子微球的结构形貌和磁性能进行表征测试。结果表明,在适当的pH值条件下,得到了粒径为150 nm~200 nm,饱和磁化强度为20.23 emμ/g,粒径均一的聚氰基丙烯酸正丁酯磁性微球。     

原位无皂乳液聚合制备纳米SiO_2/聚丙烯酸酯杂化材料纸张表面增强剂的性能研究

以聚乙烯醇为胶体保护剂,正硅酸乙酯为前躯体,通过无皂乳液聚合法合成了SiO_2/聚丙烯酸酯杂化材料纸张表面增强剂.通过红外光谱(IR)、差示扫描量热(DSC)、热重分析(TGA)和透射电镜(TEM)对杂化材料进行表征,结果表明纳米SiO_2和丙烯酸酯之间产生了化学键的结合,无机相的引入使杂化材料的热分解温度升高.初步应用实验结果表明,当增强剂用量为1%时,纸张的环压指数提高36%,抗张强度提高30%,撕裂度提高31%,拉毛强度提高30%.