取向碳纳米管/环氧树脂复合薄膜制备及结构与性能表征

碳纳米管(Carbon nanotube, CNT)/环氧树脂(Epoxy resin, EP)纳米复合材料中树脂含量、分布、CNT取向及其与树脂间界面结合是制备高性能纳米复合材料的关键因素。为了探究树脂分布和CNT/EP复合材料性能之间的关系,采用浮动催化化学气相沉积法制备的CNT薄膜和EP为原料,通过浸渍、牵伸、清洗和热压固化工艺制备CNT/EP复合薄膜。利用聚焦离子束结合扫描电子显微镜定性表征树脂在复合膜中的分布状态。结果表明,随着树脂含量增加,树脂在复合薄膜表面富集程度增加。在最优工艺条件下制备的纳米复合材料中CNT含量为66.14wt%, 拉伸强度和拉伸模量达到1405 MPa和46.7 GPa。      

用于直接甲醇燃料电池的磺化聚芳醚酮砜/聚偏氟乙烯复合膜的制备与性能

通过共混的方法制备了磺化聚芳醚酮砜(SPAEKS)与聚偏氟乙烯(PVDF)复合型质子交换膜。红外光谱(FT-IR)表明复合膜中存在C-F和O=S=O收缩振动峰。X射线衍射(XRD)结果表明,随着PVDF含量的增加,PVDF的结晶峰明显增强。扫描电镜照片显示,当PVDF含量低于20%时,有细小的晶体颗粒均匀分布在膜的表面,而当PVDF含量高于20%时,复合膜的表面和断面都有微孔存在。热重分析(TGA)证实PVDF的引入提高了膜的热稳定性。PVDF质量分数为15%的复合膜在25℃时的质子传导率保持在0.055 S/cm,而甲醇渗透系数降低到2.28×10-7cm2/s,能够满足直接甲醇燃料电池的需要。     

冠脉支架表面载药涂层的制备和性能

采用溶液聚合法制备了改性的聚甲基丙烯酸树脂,作为支架表面载药涂层的药物载体聚合物.采用浸涂法制备了不锈钢基体表面聚合物及聚合物载药涂层,并利用红外光谱及核磁共振波谱分析了所制备共聚物的成分,并评价了物理性能、生物稳定性能以及药物的释放性能.结果表明,所制备的涂层具有较好的生物稳定性,甲基丙烯酸和甲基丙烯酸丁酯的加入提高了聚合物的物理性能,尤其是涂层与金属基体的结合力所制备的药物释放涂层具有缓释紫杉醇的功能,其释放周期超过15 d.聚甲基丙烯酸树脂携带紫杉醇的载药涂层在生物稳定性、物理性能及药物释放性能方面满足冠脉支架的表面涂层的使用要求.     

聚天冬氨酸/聚醚共聚酰胺互穿网络水凝胶复合膜的制备及其性能研究

以聚琥珀酰亚胺(PSI)为改性剂,己二胺(HDA)为交联剂,通过原位交联及水解,制备了聚天冬氨酸/聚醚共聚酰胺(PAsp/PEBA)互穿网络水凝胶复合膜(PAsp/PEBA复合膜)。探讨了PAsp/PEBA复合膜的组成对膜吸水性能、水含量及其在膜中存在状态的影响;采用衰减全反射-红外光谱、扫描电镜及热重等手段对膜进行了表征。结果表明:PAsp组分的引入不但能有效调控PAsp/PEBA复合膜的含水率及其存在状态,而且能同时提高PEBA的力学性能,当PSI用量为15%(PSI占PEBA的质量分数),己二胺用量为3%时,复合膜的综合性能最优,吸水率可达32.01%,结合水含量为3.19%;拉伸强度和断裂伸长率分别比纯PEBA膜提高了21.80%和43.42%;SEM表明,当PSI用量为20%时,复合膜出现相分离。     

低介电笼型倍半硅氧烷改性氰酸酯-环氧树脂复合材料

采用环氧基倍丰硅氧烷(POSS)对双酚A型氰酸酯和环氧树脂共聚体系进行改性.系统研究了该固化体系的纳米粒子相分散状态、热性能以及力学性能、介电性能.当POSS含量为1%(质量分数)时,POsS以分子级分散在树脂基体中,该固化体系的热性能和机械性能均有明显提高,介电常数和介电损耗显著降低.随着POSS含量的提高,部分POSS以自聚和结晶的状态存在于聚合物中,体系的热性能和机械性能有所下降.     

磷酰胆碱共聚物的合成及膜的生物相容性

为了研究磷酰胆碱类聚合物的生物相容性,以偶氮二异丁腈(AIBN)为引发剂,采用自由基聚合制备了系列2-甲基丙烯酰氧乙基磷酰胆碱(MPC)与甲基丙烯酸丁酯(BMA)、甲基丙烯酸异辛酯(EHMA)的共聚物PMB、PMEH.用红外光谱、元素分析、核磁共振等方法对其结构进行了表征并探讨了其在不同溶剂中的溶解性,为该类物质的提纯提供依据;通过溶剂挥发法制备了共聚物薄膜,血小板黏附实验显示,含有MPC的聚合物薄膜比不含MPC的聚合物薄膜有更好的血液相容性;溶胀度测试显示MPC聚合物薄膜有非常好的吸收水的能力,且平衡含水量(EWC)会随着MPC在聚合物薄膜中含量的增加而增加,当MPC在PMB20中的摩尔含量为18%时,平衡含水量可以达到47%,这是磷酰胆碱类聚合物薄膜具有优良生物相容性的原因之一.     

利用氧等离子体预处理增强聚对苯二甲酸乙二醇酯/聚吡咯导电复合薄膜的界面粘附性

首先对聚对苯二甲酸乙二醇酯(PET)薄膜进行氧等离子体预处理,然后通过原位化学氧化聚合法使得吡咯单体在PET薄膜表面沉积聚合,制备了聚对苯二甲酸乙二醇酯/聚吡咯(PET-PPy)复合膜。通过原子力显微镜、X射线光电子能谱仪、ζ电位测试对经不同时长的氧等离子体预处理的PET薄膜进行表征;利用扫描电子显微镜、耐磨性实验和表面电阻测试对PET-PPy复合膜磨损前后的表面形貌和电阻进行分析与表征。结果表明,氧等离子体预处理显著增强了PET-PPy复合膜界面粘附性。氧等离子体预处理使PET薄膜表面粗糙度增大、电负性显著增强。特别地,当预处理时间为120s时,薄膜表面电负性明显增强,此时PET-PPy复合膜磨损后的电阻值变化最小,表明PET薄膜与PPy功能层界面粘附强度得到明显增强。     

水性聚丙烯酸树脂Ⅲ制备工艺改进与包衣分析

以甲基丙烯酸与甲基丙烯酸甲酯为共聚单体,用乳液聚合法制备肠溶型水性聚丙烯酸树脂Ⅲ乳液,喷雾干燥成树脂粉末.采用傅立叶变换红外光谱仪测定其组成,凝胶色谱结合多角激光光散射仪测定相对分子质量及其分布,并按照国家药典2005版规定对其生物学及机械性能进行检测.在树脂粉末中加入增塑剂邻苯二甲酸二丁酯等助剂配制包衣液,利用滚转包衣法对阿司匹林素片进行包衣,然后利用智能崩解仪观察其在胃肠液中的崩解速度,考察药物体外释放度和稳定性.结果发现制得的薄膜包衣材料无论以水还是乙醇做溶剂都具有更优良的性能.且生产包衣材料过程中未使用有机溶剂,有很好的经济和环保效益,对国内水性丙烯酸树脂包衣材料生产工业化起到很好的推动作用.     

氧化镍薄膜在含Li+电解质中的电致变色特性

本文中研究了非严格去水条件下氧化镍薄膜的电化学循环和电致变色特性．以恒电流方式向薄膜中注入和抽取Li 离子,分析了光密度变化与注入和抽取离子数量的关系,用俄歇电子能谱（AES）定量分析了注人Li 离子的深度分布．测试了薄膜在原始、致色和消色态的透射率光谱和薄膜的电流和透射率变化的时间响应,以及在开路状态下薄膜在LiClO4－PC电解液环境中的稳定性．研究了氧化镍薄膜在含有一定水杂质的LiClO4－PC电解液中的电化学循环和电致变色特性与电解质中微量水份含量的关系．发现当电解质及周围环境中含有微量水份时,对薄膜的注入电荷数量和透射率变化范围均不存在大的影响．     

纳米羟基磷灰石/壳聚糖复合膜的制备和表征

以壳聚糖(chitosan,CS)为高分子相,纳米羟基磷灰石(nano-hydroxyapatite,n-HA)为无机相,采用溶液共混和真空下溶剂挥发的方法制备了n-HA/CS复合膜,通过SEM、XRD、FTIR、接触角及力学性能等测试对此复合膜进行分析和表征.结果表明,复合膜具有非对称结构,上表面组分主要是CS,下表面组分是n-HA和CS复合体,并在底部形成了一层致密层,中间是疏松层;复合膜中CS与HA之间存在一定的化学键合并复合均匀,没有明显的相分离,且复合膜中的HA为类似于自然骨矿物相的弱结晶结构.复合膜的非对称结构对其接触角也有一定的影响,反映了膜表面亲、疏水性的不同,为细胞的粘附和旺长提供了一定的微环境.复合膜干态下的拉伸强度和断裂伸长率较纯CS膜的低,而在湿态时却较纯CS膜高.     

电致变色纳米氧化镍薄膜的溶胶-凝胶法制备与表征

以无水氯化镍、乙醇为前驱液,加入适量的丁醇和柠檬酸为稳定剂,通过回流、水解得到稳定的溶胶;采用浸渍-提拉的方法在ITO导电玻璃上形成均匀的膜层;分析了溶胶制备中加水量的影响;研究了热处理温度对制备膜层的结构、光透过率的影响;对经过不同处理的膜层进行X射线衍射、透射电子显微镜、扫描电子显微镜、热重分析等研究表明:在空气中加热到350℃、保温30min薄膜分解为稳定的具有立方结构的NiO纳米晶;以氢氧化钾水溶液为电解质的循环伏安、电致变色实验结果表明制备的纳米氧化镍薄膜具有良好的电致变色特性.     

The Effect of Plasticizers on the Properties of Polyvinyl Alcohol Films

Abstract

The effect of water-soluble plasticizers viz propylene glycol (PG), glycerol and polyethylene glycol 600 (PEG) on the morphology and water resistance of polyvinyl alcohol (PVA) films was investigated. Polyvinyl alcohol films were cast from aqueous solutions, and their morphology studied using differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). Water resistance was characterized by the extent of film dissolution and the water uptake capacity of remnant films after immersion of the films in distilled water for 3 days at 37° C. DSC thermograms showed that crystallite formation in the PVA films was affected to different extent by addition of the three plasticizers. The plasticizers not only reduced the degree of crystallinity in the films, but also lowered the crystalline melting temperatures probably by introducing defects into the crystal lattice. This factor, coupled with leaching of the water-soluble plasticizers from the films when immersed in distilled water, lowered the water resistance of the plasticized PVA films. The influence of plasticizers on the properties of PVA films was further related to the degree of compatibility between the plasticizers and PVA.     

Improvement of Interface in SiC Particle-Reinforced Al-Li Composite by Sol-Gel Coating Technique

This paper describes a study to investigate an improvement of the interface in SiC particle-reinforced Al-Li composite by coating the SiC particle with metallic oxide film. A coating method utilizing a sol-gel technique produced fine SiC powders covered with SiO₂, TiO₂, or ZrO₂ metallic oxide film. The film thickness was not affected by the hydrolysis time of the sol solution under a dry argon atmosphere. The average thickness of the SiO₂, TiO₂ and ZrO₂ films was about 10 nm, 8 nm and 27 nm, respectively. In metallic oxide coated SiC particle-reinforced Al-Li composite, TEM observation showed that the coating film was not damaged by fabrication processing, and that the formation of Al⁴C³ at the interface between the matrix and reinforcement was controlled by the coating film. The tensile strength and elongation of the extruded TiO₂, coated sample increased by 12% and 24%, respectively, compared with the non-coated sample.     

可降解超疏水聚乳酸塑料薄膜的制备及性能研究

采用相分离法,以可降解聚合物聚乳酸(PLA)和聚碳酸亚丙酯(PPC)为原料制备超疏水塑料薄膜,研究原料配比、溶剂处理温度、溶剂处理时间等对塑料薄膜疏水性的影响。结果表明:当PLA质量分数为70%,在50℃下二甲基亚砜(DMSO)处理25min后制得的塑料薄膜接触角为155°,呈超疏水性。该薄膜具有良好的降解性能,强制降解条件下,5d降解率达到34.13%。扫描电镜照片显示塑料薄膜多孔并具有蜂窝状结构,具有粗糙的表面形貌。进一步采用低表面能的含氟丙烯酸酯树脂对其进行表面修饰,表面修饰后塑料薄膜接触角提高到164°。     

PU/PA核壳乳液/水分散异氰酸酯交联成膜机理及其性能研究

制备了双组份水性聚氨酯木器涂料,探讨了羟基组分聚丙烯酸酯(PA)含量和固化剂用量对涂膜强度以及耐溶剂性、硬度和抗冲击性能等影响,并根据粒径分析和透射电子显微镜(TEM)等测试方法研究了羟基聚氨酯-丙烯酸酯复合乳液(PUA)和固化剂的反应情况及树脂结构。结果表明,PA含量为15%,固化剂加入量为5%时得到稳定性、涂膜硬度、韧性、耐溶剂性较优的水性聚氨酯木器涂料。     

Kesterite based thin film absorber layers from ball milled precursors

The existing thin film technology involves rare earth and toxic materials. Cu₂ZnSnS₄, its selenide and sulfo selenide analogues have acquired as the most promising alternate absorber material group in thin film technology due to the abundance and non toxic constituent elements. We present a facile, green and low cost method for synthesis of CZTS/(Se) films. Precursor powders using Cu, Zn, Sn, S and Se, was prepared by ball milling. Starting with ball milled metallic precursor powders we synthesized kieserite thin films by doctor blade coating process and subsequent annealing. Doctor blade coating method is one of the cheapest non toxic non vacuum based chemical deposition processes. A comparative study of ball milled powder and films prepared from the precursors has been presented and interesting aspects of structure, morphology and composition were explored after ball milling, and films formed after annealing. Chalcogens (S or Se) plays an important role in the construction of tetragonal phase. A combined TGA–DSC, X-ray diffraction, Raman, TEM, EDX and UV–Vis–NIR study showed marked change in film property after annealing.     

不同成膜工艺对PCL结晶及微生物降解性能的影响

将压延成膜和溶剂成膜制备的聚ε-己内酯(PCL)膜放入降解液进行100d的生物降解,以研究不同成膜工艺对PCL降解性和降解前后结晶的影响。采用显微镜观察降解前后薄膜表面形态变化;通过广角X射线衍射法(WAXD)表征其降解前后结晶变化;利用凝胶渗透色谱(GPC)测定降解过程中PCL相对分子质量和分子量分布的变化。研究结果表明,溶剂成膜工艺可提高PCL亲水性,增大结晶尺寸,提高PCL降解性;而压延成膜工艺使膜表面致密,结晶尺寸减小,但对结晶形态和结晶度影响不大,降解后PCL晶形均未发生大的变化,结晶度有所下降。     

Cu2ZnSnS4 films by paste coating and their optoelectronic properties

Cu₂ZnSnS₄ (CZTS) thin films were prepared by a paste coating method as the absorb layer of solar cells. This method is more eco-friendly using ethanol as solvent and more convenient than traditional sol–gel method. The effects of sulfurization temperature on properties of thin film were studied. The results of X-ray diffraction and Raman spectroscopy showed the formation of kesterite structure of CZTS films. The scanning electron microscopy images revealed that CZTS thin film obtained at 550 °C were compact and uniform. The optical band gap of the CZTS film was about 1.5 eV, and the CZTS film had an obvious optoelectronic response. Moreover, CZTS solar cell was prepared with a conversion efficiency of 0.47 %.     

层叠状功能化石墨烯纳米带/TPU复合材料薄膜的制备与性能

利用溶液涂覆成膜工艺在涂膜机上制得层叠状功能化石墨烯纳米带（SF-GNRs）/热塑性聚氨酯（TPU）复合材料薄膜。采用FTIR、XRD、XPS、TEM和FE-SEM对SF-GNRs的结构进行表征,并结合复合材料薄膜的氧气透过率、体积电阻率测试及表面形貌观察,研究了不同质量分数的SF-GNRs对TPU复合材料薄膜阻隔和抗静电性能的影响。结果表明:所得高比表面积SF-GNRs在TPU基体中分散良好;当SF-GNRs质量分数为1.0%时,SF-GNRs/TPU复合材料薄膜的氧气透过率相比纯TPU薄膜降低了67.76%,阻隔性能得到明显改善;当SF-GNRs质量分数达到1.0%～1.5%时,SF-GNRs/TPU复合材料薄膜出现了电渗流行为,表现出优良的室温导电性能。      

Effect of filler types and calcination temperature on the microstructure and the nitric oxide photocatalytic activity of composite titanium dioxide films

The composite titanium dioxide (TiO(2)) films coating on the woven glass fabric were prepared by a modified sol-gel process, using pre-calcinated TiO(2) nanoparticle or silica gel as filler. The characterized physicochemical properties of the prepared catalyst films showed that the specific surface area, the microstructure and the crystal structure of the catalysts were greatly affected by the fillers and the calcination temperature. The physicochemical properties of composite films and the photocatalytic activity of nitric oxide (NO) show that the pre-calcinated TiO(2) nanoparticle is more favorable than silica gel as filler. The pre-calcinated TiO(2) nanoparticle filler can increase the photocatalytic activities of the catalysts by increasing the specific surface area, introducing a bimodal mesoporous structure, and creating a polymorphous crystal structure. And the TiO(2)-TiO(2) film calcinated at 400 degrees C exhibits the highest photocatalytic activity for NO oxidation and is more active than Degussa P25.