表面改性高模高强碳纤维与环氧树脂界面相容性研究

采用阳极氧化法对高模高强碳纤维表面改性,改性后上浆处理。经润湿性能测试,改性后碳纤维的接触角由改性前的66.3°降至27.8°,表面活性增加,润湿性能改善。采用扫描电镜和原子力显微镜对其表面结构进行表征,发现改性后碳纤维表面粗糙度增加,分散性较好。对其环氧树脂复合材料进行力学性能测试,结果表明复合材料界面剪切强度和层间剪切强度分别增至42.3 MPa和43.6 MPa,且增加程度与纤维表面粗糙度成正比。     

没食子酸/乙二胺共沉积聚酯纤维制备及其成纸性能

赋予疏水性聚酯短切纤维亲水性能，可拓展其应用价值。本文提出在碱性Tris缓冲液中，使没食子酸与乙二胺通过迈克尔加成或席夫碱反应共沉积在聚酯短切纤维表面。测定了改性前后聚酯短切纤维的动态接触角，采用扫描电子显微镜（SEM）观察了纤维的微观形貌，利用傅里叶变换红外光谱（FT-IR）和X射线光电子能谱（XPS）表征了纤维表面结构的变化，最后以改性前后聚酯短切纤维和阔叶木浆抄纸，测定了纸张的孔径分布变化和透气性，并测试了纸张物理性能。结果表明：经共沉积改性后的聚酯短切纤维表面存在大量羟基，纤维表面有氮元素生成，同时表面粗糙度提高，与未改性聚酯短切纤维相比，改性后聚酯短切纤维与去离子水的接触角降低了57.2?，显著改善了纤维亲水性；与未改性纤维纸页相比，改性后纤维纸页抗张强度提高35.2%，湿强度提高43.3%，透气度提高11.1%，相同孔径范围内孔径增加了24%-30%，纤维分散性明显提高。本研究成果可制得亲水性优良的聚酯纤维，并可用于高性能纸张的应用。     

氨气等离子体改性处理芳纶Ⅲ表面的研究

以氨气为反应气体,对芳纶Ⅲ进行等离子体表面改性处理,研究了等离子体处理时间和处理功率对纤维表面性能的影响;采用X射线光电子能谱、场发射扫描电镜、接触角和微脱粘实验等测试方法对改性前后纤维表面元素组成、形貌、润湿能力以及界面粘结强度进行表征。结果表明:芳纶Ⅲ经过氨气等离子体改性后,表面含氮极性基团的含量增加,粗糙程度增大,润湿能力得到明显的改善;当氨气等离子体处理时间为15 min,功率为100 W时,芳纶Ⅲ与环氧树脂的界面粘结强度从处理前的12.9 MPa提高到18.2 MPa,与水的接触角由处理前的71.4°下降到46.8°。     

没食子酸/乙二胺共沉积聚酯纤维的制备及其成纸性能

在碱性三羟甲基氨基甲烷(Tris)缓冲液中,将没食子酸与乙二胺通过迈克尔加成和席夫碱反应共沉积在聚酯短切纤维表面.测定了改性前后聚酯短切纤维的动态接触角,采用SEM观察了纤维的形貌,利用FTIR和XPS表征了纤维表面结构的变化,最后以改性前后聚酯短切纤维和阔叶木浆抄纸,测定了纸张的孔径分布变化和透气性,并测试了纸张物理性能.结果表明,经共沉积改性后的聚酯短切纤维表面存在大量羟基,纤维表面有氮元素生成,同时表面粗糙度提高,与未改性聚酯短切纤维相比,改性后聚酯短切纤维与去离子水的接触角降低了57.2°,显著改善了纤维的亲水性;与未改性纤维纸页相比,改性后纤维纸页抗张强度提高了35.2％,耐破指数提高了13.1％,透气度提高了11.1％,相同孔径范围内的孔径占比增加了23％～29％,纤维分散性明显提高.     

基于紫外⁃臭氧辐照的挤塑聚苯乙烯表面改性研究

采用紫外?臭氧（UVO）辐照方式对挤塑聚苯乙烯保温板（XPSF）进行了表面改性，通过X射线光电子能谱仪（XPS）、接触角测量仪（CA）和扫描电子显微镜（SEM）对改性前后XPSF表面化学结构、润湿性能及表面形貌的变化规律进行了表征和测试。结果表明，随着UVO辐照时间的延长，XPSF表面含氧官能团数量逐渐增加，尤其在15 min时，XPSF表面的O/C值（O和C原子含量比值）由0.04增加至0.59；经UVO辐照30 min后，XPSF表面与水的接触角从未经处理的101.7°降至37.1°；UVO辐照前后XPSF表面形貌差异很小；随着放置时间的延长，XPSF表面氧含量逐渐降低，表面形成的含氧官能团消失，疏水性产生一定恢复；放置7 d时XPSF表面仍为氧化状态，接触角表现为亲水性；放置14 d时XPSF表面化学性质和润湿性已恢复至原始状态，但XPSF表面形貌并不会随放置时间的变化而改变。     

短切聚酰亚胺纤维增强混凝土性能

通过酸洗、化学接枝的方法对短切聚酰亚胺纤维进行表面改性，并对不同配比的短切聚酰亚胺纤维增强混凝土进行了相关性能研究。结果表明，硅烷偶联剂成功接枝到聚酰亚胺纤维表面，并且改性后的聚酰亚胺纤维能够提高纤维在混凝土内的分散性，并对混凝土性能有较为明显的提升作用，w(改性聚酰亚胺纤维)=0.8%,混凝土的综合性能达到最优值。     

湿法造纸技术制备聚酰亚胺纤维增强体及其对热塑性树脂基复合材料力学性能的影响

利用湿法造纸成形技术抄取得到聚酰亚胺纤维纸,分别以等质量的聚酰亚胺纤维、聚酰亚胺纤维纸为增强体,采用手糊成型、热压法制备热塑性聚酰亚胺树脂基复合材料。聚酰亚胺纤维纸增强体改变了纤维的存在形式,解决了复合材料中纤维束多、纤维孔径分布不匀、有效长度低、材料力学性能不佳等问题,纸增强复合材料拉伸性能提高130%,弯曲性能提高108%,层间剪切性能提高34.5%。聚酰亚胺纤维纸增强体自身因素影响了复合材料力学性能,从纤维长度、打浆状况、纸页定量角度分析了复合材料力学性能改善的原因。     

基于水热处理的镁合金超疏水表面制备及其腐蚀防护性能研究

为了改善镁合金表面较差的耐腐蚀性能,对镁合金表面依次进行了水热处理和低表面能物质修饰处理,并利用扫描电子显微镜、X-射线衍射仪、接触角测量仪对其表面形貌、表面组成和表面润湿行为进行了研究。结果表明,经水热处理后,镁合金表面生产了一层结构粗糙的氢氧化镁,经低表面能物质修饰之后,接触角可达158.5°,滚动角8°,显示出优异的超疏水性。电化学测试结果表明,制备的超疏水表明腐蚀防护性能优异。     

聚酰亚胺(PI)/无机纳米复合材料的制备、结构与性能

依据国内外聚酰亚胺（PI）／纳米复合材料的最新研究进展，重点阐述PI复合材料的制备、结构、性能及应用，展望了PI复合材料的发展趋势。列举了几种常用纳米粉体的特性，介绍了聚酰亚胺（PI）纳米复合材料的3种制备方法：溶胶一凝胶法、插层复合法、直接分散法，由于纳米粉体在PI材料中的分散性良好，使整个聚合物基体形成新的网络结构，利用纳米粉体改变了PI材料的性能，如力学性能、热学性能、加工流动性等，插层剂的加入对PI纳米复合材料的复合体系有明显改善作用。     

微波辐射改性秸秆/HDPE复合材料的界面性能

利用微波接枝偶联剂处理秸秆纤维,采用光学法液滴形态分析系统测定3种不同方法处理的秸秆微粉的动态接触角及表面能变化,并制备相应的复合材料进行力学性能测试.研究结果表明:几种界面改性方法对秸秆微粉均有较好的改性效果,微波/KH550改性效果最佳,微波/钛酸丁酯次之,再次为直接微波处理.经微波处理后秸秆纤维的平衡接触角θe由40.26°上升到42.97°,经微波/钛酸丁酯处理后平衡接触角θe由40.26°上升到50.33°,而发现经微波/KH550处理后平衡接触角θe由40.26°上升到94.01°.而表面能则有不同程度减小,经微波/KH550处理后秸秆纤维表面能接近HDPE基体;经界面改性处理的秸秆纤维,其复合材料的拉伸强度提高0.40%～19.79%,冲击强度提高7.21%～15.29%.动态接触角法研究液体润湿微粉的动力学特性具有快速、准确、操作简单的特点,为研究植物纤维表面改性接枝等提供理论基础.     

阳极氧化处理对碳纤维强度离散性的影响及表征

采用阳极氧化法对碳纤维进行了表面处理,并探讨了表面处理后碳纤维接触角、强度的变化和碳纤维强度离散性的表征方法。研究发现:碳纤维在阳极氧化表面处理后,接触角变小,说明浸润性增强,强度略有下降,离散性略有增大;表面处理后随放置时间延长,接触角有一定程度增大,强度继续下降,离散性继续增大。用强度CV值和韦伯分布拟合强度所得的韦伯模数两种不同指标表征了表面处理后碳纤维的强度离散性,经验证,两种表征方法的一致性好。     

Effect of Surface Modification on Mechanical and Tribological Performance of Poly-p-phenylenebenzobisoxazole Fiber-Reinforced Polyimide Composite

This work examined the effect of coupling agent surface modification of Poly-p-phenylenebenzobisoxazole (PBO) fibers on mechanical and tribological performance of PBO fiber-reinforced thermoplastic polyimide (PBO/PI) composites. The results show that tensile strength and flexural strength are largely improved by coupling agent treatment. Under dry sliding conditions, coupling agent treatment is effective to reduce the wear of PBO/PI composite. The principle of improvement in interfacial adhesion between PBO fiber and PI matrix after coupling agent treatment was discussed. The surface characteristics of PBO fibers were characterized by X-ray photoelectron spectroscopy (XPS). It is found that the content of polar groups on the surface of PBO fiber treated by coupling agent increases compared with the untreated fiber. The presence of polar groups is probably leading to an increment of interfacial binding force between fibers and matrix in a composite system, and accordingly enhances the mechanical and tribological properties.     

Wettability assessment of plasma-treated PBO fibers based on thermogravimetric analysis

Changes in the surface wettability of poly(p-phenylene benzobisoxazole) (PBO) fibers were investigated by thermogravimetric analysis (TGA) following an air dielectric barrier discharge (DBD) plasma treatment. The results were then supplemented and confirmed by scanning electron microscopy (SEM), dynamic contact angle analysis (DCAA), X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM) measurements. After exposure to the DBD plasma at a pre-determined power level, TGA analysis showed that the residual rates retained by the PBO composites decreased, which meant an increase in the amount of resin coating the PBO fibers in the composites. Observations by SEM confirmed that there was more resin adhering to the treated PBO fibers and the wetting behavior of resin on the fibers was greatly improved. Meanwhile, DCAA for the treated fibers showed a significant enhancement in fiber surface free energy. XPS and AFM were performed in order to reveal any variations in fiber surface activity and surface morphology resulting from the surface treatment. The resulting data showed that increases in oxygen-containing polar groups and surface roughness on the plasma-treated PBO fibers contributed to the above improved wetting behavior. With comprehensive analyses, it was concluded that TGA could be used as a supporting method assessing the surface wettability of PBO fibers before and after air DBD plasma treatment.     

低温等离子体对国产聚酰亚胺纤维的亲水性改性研究

采用低温等离子体改性技术,对国产聚酰亚胺纤维进行表面改性,从而提高了国产聚酰亚胺纤维的润湿性。对改性后的聚酰亚胺纤维进行表面形貌、表面化学结构、纤维力学性能、纤维静态水接触角以及束纤维芯吸效应的测试与分析,得知低温等离子体改性可以对国产聚酰亚胺纤维的表面进行刻蚀,使光滑的纤维表面出现凹槽,同时可以引入大量的亲水性官能团,提升纤维亲水性。当放电功率为130 W、放电时间为240 s、放电压强为25 Pa时,聚酰亚胺纤维的亲水性得到较大的改善,同时强力损失相对较小。     

A comparative study on the effect of VUV radiation in plasma SiOx-coated polyimide and polypropylene films

Wettability of polyimide (PI) and polypropylene (PP) films have been improved using SiO_x-like thin layers deposited from a mixture of hexamethyldisiloxane (HMDSO) and oxygen in a microwave distributed electron cyclotron resonance plasma reactor. The films wettability evolution behaviors were evaluated through the results of contact angle measurements, atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). The plasma depositions of SiO_x thin layers in presence of VUV radiation induce a contact angle decrease to about 7° and 35° for PI and PP films, respectively. XPS data showed that such difference in wettability is attributed to the increase of hydrophilic group's proportion at the surface of coated PI films due to VUV irradiation. AFM images showed that the PI surface topography remains relatively smooth when coated in presence of VUV radiation. However, in the case of PP films, AFM images revealed the growth of irregular structure due to a substrate etching effect supported by VUV radiation. For polymers coated without VUV irradiation, the deconvolution of the C1s peaks showed a significant decrease of CO bonds for both PI and PP substrates.     

纳米芳纶增强聚酰亚胺气凝胶纤维的制备及其性能研究

以3,3′,4,4′-联苯四甲酸二酐和1,4-二氨基苯二胺共聚制备聚酰胺酸盐前驱体溶液,通过湿法纺丝,然后经过超临界二氧化碳干燥和热亚胺化处理制得纳米芳纶(ANFs)增强聚酰亚胺(PI)气凝胶纤维(简称PI/ANFs气凝胶纤维),研究了气凝胶纤维的结构与性能。结果表明:傅里叶变换红外光谱和X射线衍射光谱表征所制备的PI/ANFs气凝胶纤维为目标产物;PI/ANFs气凝胶纤维的截面具有大量的孔结构且分布较为均匀;PI/ANFs气凝胶纤维的比表面积为152 m²/g,孔径主要分布在10~25 nm之间,密度为0.21 g/cm³,孔隙率大于85%;PI/ANFs气凝胶纤维在空气气氛下的最大热分解温度为625℃,在氮气气氛下950℃的残炭率为67%;PI/ANFs气凝胶纤维的断裂强度和初始模量分别为(2.5±0.5)MPa和(109±10)MPa。     

Surface modification of ultra-high strength polyethylene fibers for enhanced adhesion to epoxy resins using intense pulsed high-power ion beam

The effects of intense pulsed high power ion beam (HPIB) treatment of ultra-high strength polyethylene (UHSPE) fibers on the fiber/epoxy resin interface strength were studied. For this study, argon ions were used to treat Spectra? 1000 (UHSPE) fibers in vacuum. Chemical and topographical changes of the fiber surfaces were characterized using Fourier transform infrared spectroscopy in attenuated total reflectance mode (FTIR-ATR), X-ray photoelectron spectroscopy (XPS), dynamic wettability measurements, and scanning electron microscopy (SEM). The fiber/epoxy resin interfacial shear strength (IFSS) was evaluated by the single fiber pull-out test. The FTIR-ATR and XPS data indicate that oxygen was incorporated onto the fiber surface as a result of the HPIB treatment. The wettability data indicate that the fibers became more polar after HPIB treatment and also more wettable. Although the total surface energy increased only slightly after treatment, the dispersive component decreased significantly while the acid-base component increased by a similar amount. SEM photomicrographs revealed that the surface roughness of the fibers increased following the HPIB treatment. The single fiber pull-out test results indicate that HPIB treatment significantly improved the IFSS of UHSPE fibers with epoxy resin. This enhancement in IFSS is attributed to increased roughness of the fiber surface resulting in mechanical bonding and in increased interface area, increased polar nature and wettability, and an improvement in the acid-base component of the surface energy after the HPIB treatment.     

低温等离子体处理对PBO纤维润湿性的影响

为改善PBO纤维的润湿性,拓宽其应用领域,探究了空气低温等离子体处理对PBO纤维润湿性的影响。通过芯吸效应和接触角表征处理前后PBO纤维润湿性,并采用扫描电子显微镜SEM观察处理前后PBO纤维表面形貌,用X射线光电子能谱仪(XPS)对处理前后PBO纤维表面化学组成进行定性分析。实验结果表明,改性后PBO纤维芯吸高度大幅上升,接触角明显降低,并且在其表面产生明显刻痕,局部有剥离现象,改性后PBO纤维O、N元素含量均有所提高,PBO纤维润湿性明显增强。()     

聚酰亚胺在微电子领域的处理方法

在微电子封装领域,采用等离子体处理聚酰亚胺(PI),主要考察粗糙度、润湿性及刻蚀速率3个指标。改变PI层粗糙度主要依靠粒子的物理轰击而改变表面微观形貌来实现。随着时间累加,Ar等离子体对PI层轰击作用逐渐增强。改变PI层润湿性主要依靠O2等离子体与PI反应,在PI表面产生OH,进而提高PI层亲水性。随着O2等离子体处理时间增大,水滴角先是逐渐下降,90 s后水滴角基本保持不变。提高PI层的刻蚀速率主要通过在O2中添加四氟化碳(CF4)实现。随着O2中CF4的含量增加,PI的刻蚀速率逐渐增大,并在CF4含量达到20%时,刻蚀速率达到最大,随后刻蚀速率逐渐降低。