涂料的耐核辐射性能研究

开展了耐核辐射涂料研发项目的预实验,研究了2种涂料样品在室温下空气气氛中经60Coγ射线照射后的辐照效应。采用傅里叶红外分析仪(FTIR)对辐照前后的样品成分和结构变化进行了分析,并筛选出在核辐照条件下结构比较稳定的基团。结果表明:在60Coγ射线辐照下,涂料中不同化学基团表现出的辐照效应各不相同,在5×106Gy的吸收剂量范围内,苯环、酯羰基和醚键等基团比较稳定,耐核辐射性能好,醛基和亚氨基等基团不稳定;CC双键和羧羰基等基团在吸收剂量不大于5×106Gy的60Coγ射线辐照后,会发生辐照交联和辐照接枝等反应。预实验取得了比较满意的结果,达到了开展预实验的目的。     

掺铈锂铝硅系统玻璃耐辐照性能的研究

采用LiO-Al2O3-SiO2系统为基础玻璃,CeO2为稳定剂,制备出耐辐照玻璃。研究了CeO2含量、熔制气氛及辐照剂量对玻璃耐辐照性能的影响。本文首次提出用耐辐照损伤因子Z表征玻璃的耐辐照稳定性。     

耐辐照助剂对三元乙丙橡胶性能的影响

研究了4种耐辐照助剂[四氧化三铅(Pb_3O_4)、碳化钨(WC)、氧化铈(CeO_2)、氧化钇(Y_2O_3)]对三元乙丙橡胶胶料性能的影响。结果表明:添加耐辐照助剂的胶料保持了较好的耐热老化性能,耐辐照性能大幅提高;耐辐照助剂品种及用量对胶料力学性能、耐热老化性能和耐辐照性能的影响差异较大;耐辐照助剂最优组合为:Pb_3O_4 30,WC 5,CeO_2/Y_2O_3 10,在此条件下胶料具有良好的耐辐照性能和综合物理性能,可延长橡胶制品在辐照环境下的使用寿命。     

聚偏氟乙烯中空纤维膜的耐辐射性能研究

研究了较低剂量的γ辐射对聚偏氟乙烯中空纤维膜的结构与性能的影响。在试验中,选用44.57 Gy/min的剂量率,分别采用2,4,6,10 kGy剂量对浸泡在pH=10的氢氧化钠溶液中的中空纤维膜进行辐照。对辐照前后的样品作相关的性能测试,结果表明:随着辐射剂量的增加,透水通量先增大后减小,最大孔径持续减小,最大幅度至14.9%,分离性能增强。在≤10 kGy的剂量内,断裂强力呈现增大趋势,断裂伸长率呈现下降趋势,爆破强度先增大后减小。工艺优化的剂量为2 kGy。微观形貌和红外分析表明,辐射对膜的外表面化学基团及内表面的形貌产生一定的影响。热分析表明,辐照使膜的结晶度有所提高。     

阻尼材料耐辐照性能研究

对航天领域常用的2种阻尼材料进行了耐辐照性能研究,对比分析了其辐照前后的力学性能、阻尼性能和应力松弛。结果表明,苯基硅橡胶和氟硅橡胶在受到2. 9×103rad剂量的辐照后,邵尔A硬度、拉伸强度、拉断伸长率、储能模量、应力保持率均升高,在1～80 Hz内的损耗因子均降低。苯基硅橡胶上述性能的变化幅度小于氟硅橡胶,耐辐照性能更好。     

聚三氟苯乙烯耐辐射性能的研究

聚三氟苯乙烯(PTFS)是三氟苯乙烯的均聚物,随着能源危机的加剧和绿色能源的兴起而成为研究热点。采用分析天平、乌氏黏度仪、红外光谱和差热分析仪研究了辐照剂量对PTFS结构和性能的影响。研究证实,随着辐照剂量的增加,PTFS的质量和化学结构变化不大,但PTFS的分子质量、玻璃化转变温度和热容差逐步降低。同时也证实了PTFS的耐辐射性较聚四氟乙烯好,这为聚四氟乙烯的耐辐射改性提供了一种方法。     

无机填料对不同结构聚丙烯耐紫外光性能的影响

采用熔融共混法研究了滑石粉、绢云母和碳酸钙分别对均聚聚丙烯(PPH)、嵌段共聚聚丙烯(PPB)、无规共聚聚丙烯(PPR)耐紫外光降解性能的影响,并通过色差分析、体视显微镜、傅里叶变换红外光谱等表征其微观结构和宏观性能。结果表明:PPB/无机填料复合材料的耐紫外光性能最好;与片层的滑石粉和绢云母相比,碳酸钙与聚丙烯基体的界面黏接性较差;PPH/绢云母、PPB/绢云母、PPR/绢云母的羰基指数分别为0.11,0.14,0.02;相较于其他两种无机填料,PPR/绢云母复合材料的羰基指数最小、耐紫外光性能较好。     

一种新型的用于单线态氧检测的比率型荧光探针

单线态氧(¹O₂)是一种重要的高活性氧分子,在生理学和病理过程中起着关键作用。本文构建了¹O₂ 响应的基于光诱导电子转移(PET)机理的比率型荧光探针Com-Nap。该探针以扩环香豆素和萘酰亚胺衍生物为荧光团,以蒽和扩环香豆素为识别基团,同时以蒽作为萘酰亚胺荧光团的猝灭基团。单独的探针仅表现出扩环香豆素的荧光信号。当¹O₂与探针反应后,PET过程被禁阻,呈现出比率型响应信号。该探针实现了对¹O₂的准确、快速及高选择性检测。     

钴~(60)-γ射线辐照法对骨蜡中指示病毒灭活效果的验证

目的验证钴60-γ射线辐照对骨蜡中模拟污染指示病毒的灭活效果。方法将固体骨蜡制成腔壁0.7 cm厚的空心圆柱体的辐照用样品,空腔中分别加入6.61 Lg PFU/ml辛德毕(Sindbis)病毒、7.07 LgTCID50/0.1 ml脑心肌炎病毒(encephalomyocarditis virus,EMCV)和6.01 LgTCID50/0.1 ml猪细小病毒(porcine parvovirus,PPV),分别经5、10、15、20及25 kGy的钴60-γ射线进行辐照后,收集样品腔中的病毒液,采用噬斑形成法检测Sindbis病毒滴度,采用微量半数细胞病变法检测PPV和EMCV滴度。结果经不同剂量kGy钴60-γ射线辐照,Sindbis病毒、EMCV及PPV的病毒滴度随辐照剂量的增加而下降,辐照剂量增加至25 kGy时,可灭活3种病毒的量分别达6.03⁶.60 LgPFU/ml、6.256.60 LgPFU/ml、6.25⁶.32 Lg TCID50/0.1 ml和4.756.32 Lg TCID50/0.1 ml和4.75⁴.88 LgTCID50/0.1 ml以上。结论 25 kGy的钴60-γ射线对骨蜡中的包膜和无包膜病毒均有较好的灭活效果。     

丙烯酸酯橡胶耐有机溶剂及耐油性的研究

采用平衡溶胀法测定了日本瑞翁公司生产的活氯型丙烯酸酯橡胶(AR840)在24种不同有机溶剂中的溶胀行为,得到了AR840的一维溶解度参数值,其范围在18~23(MPa)^1/2之间。进一步用汉森三维溶解度参数软件(HSPiP)对溶胀数据进行分析研究,得到AR840三维溶解度参数值,色散分量(δ_d)、极性分量(δ_p)和氢键分量(δ_h)分别为18.20、8.70、3.60(MPa)^1/2。结果表明,AR840与24种溶剂存在着能量差(R_a),AR840与溶剂的溶胀比随着它们之间的Ra值的变化呈现反“S”型曲线,借助Ra的大小可以表征AR840在有机溶剂中的溶胀特性,能相对准确地表征丙烯酸酯橡胶(ACM)耐有机溶剂及耐油性能,对耐有机溶剂及耐油ACM的配方设计有一定的指导意义。     

Hydroxyapatite Coating on Titanium Substrate by the Sol-Gel Process

Hydroxyapatite coatings on titanium were attempted by a sol-gel process combined with conventional heat treatment and with UV irradiation at ambient temperature after dipping/ withdrawing a substrate into/from the sol. X-ray diffraction data showed that a coating film prepared by heat treatment was amorphous and crystallized in Ca₅(PO₄)₃(OH) at a temperature of 773–973 K. The infrared spectra for coating films that have been prepared by heat treatment at a temperature of 573–873 K were in fair agreement with those for a coating film prepared by UV irradiation. After ethylene oxide sterilization, the cytotoxicity of coating film decreased with increasing irradiation time in UV irradiation, whereas it decreased with increasing temperature in conventional heat treatment. In comparisons between ethylene oxide sterilization and autoclave sterilization, the coating film sterilized by autoclave had much lower cytotoxicity than that sterilized by ethylene oxide. Furthermore, an animal test in the transfemoral drill hole on a rat for 4 weeks was examined using an implant prepared by heat treatment and autoclave sterilization. The sol-gel-coated titanium had slightly higher bone apposition than uncoated titanium as a control material.     

环氧豆油树脂涂层的防腐性能研究

以环氧大豆油（ESO）为主要原料,四亚乙基五胺为固化剂,在碳钢基底表面制备了环氧豆油树脂（ESOR）涂层。利用场发射扫描电镜、傅里叶红外变化光谱仪、纳米压痕仪、热重分析仪、接触角测量仪、电化学阻抗谱等技术对ESOR涂层的性能进行了表征。结果发现,原料中ESO的含量有助于提高ESOR涂层的耐水性;而当原料中ESO的含量逐渐增加时,ESOR涂层的硬度、弹性模量和耐蚀性都会随之增强;根据拟合的等效电路,ESO与四亚乙基五胺的摩尔比为2的ESOR涂层的涂层电阻R_c能达到8.22×10¹¹ Ω·cm²,电荷转移电阻R_ct能达到1.32\times10¹⁰ Ω·cm²,表现出了优异的防腐性能。     

改性石墨烯对环氧树脂涂层耐腐蚀性能的影响

将改性后石墨烯粉末通过球磨机均匀分散于环氧树脂涂料中以提高7A52铝合金表面有机涂层的耐腐蚀性能。通过接触角、吸水率、红外光谱、开路电位及交流阻抗测试,分别评价改性石墨烯环氧树脂涂层的表面润湿性、耐水性能、耐蚀性,并通过扫描电子显微镜对石墨烯粉末及环氧树脂涂层断面形貌进行分析。结果表明:环氧树脂涂料中添加0.8%改性石墨烯粉体后,接触角由86.77°增加至101.43°,提高16%,表面由亲水性变为疏水性,涂层的耐水性提高,吸水率降低0.21%。0.8%改性石墨烯涂层在3.5%NaCl溶液中稳定后的开路电位较未添加石墨烯涂层增加0.14 V,阻抗值高出未添加改性石墨烯涂层半个数量级,且电荷转移电阻R_ct比未添加改性石墨烯涂层R_ct高出1.78×10 ⁷ Ω/cm ²,涂层的耐腐蚀性大大提高。红外光谱表明,改性石墨烯并未改变环氧树脂结构,涂层中的改性石墨烯是影响涂层性能发生变化的重要因素。研究表明改性石墨烯的加入可以有效提高涂层的耐蚀性,并且当改性石墨烯添加量为0.8%时,涂层具有优异的耐腐蚀性能。     

复合外墙隔热涂料的制备和隔热性能研究

制备了2类复合外墙隔热涂料,一类是将反射型、辐射型、阻隔型3种功能填料按一定比例复合配制外墙隔热涂料;另一类是分别制备反射、辐射、阻隔涂层,并将这3种涂层按2种方式叠加复合,构成外墙隔热涂层。3种功能填料复合涂层在红外灯照射下的绝对温升为27.4℃,在波长为250~2 500 nm范围内的太阳反射比为87%,半球发射率为89%;在太阳光照射下,功能填料复合涂层的热箱内最高温度分别比未涂覆的空石棉板、空白样、叠加复合涂层、单涂反射涂层、单涂辐射涂层和单涂阻隔涂层低11.0℃、5.5℃、0.9℃、2.1℃、3.8℃和1.2℃。研究结果表明:将3种功能填料以一定比例复合配制的涂层隔热效果优于3种隔热机理涂层叠加而得的复合涂层,更优于单一隔热机理涂层。     

Performance of polyester and modified polyester coil coatings exposed in different environments with high UV radiation

Coil coating is a continuous strip coating technology, which enjoyed rapid growth. It provides a cost-effective method of applying a coating to a metal substrate with a low solvent emission, and nowadays paints of different nature are applied this way on a range of metal substrates, for a large variety of products and uses.

Coil coatings can be more or less degraded by high UV radiation. However, differences in distribution of light intensity as a function of wavelength between exposure environments, can lead to significant differences in the degradation results, depending on coating nature. In this work, the behaviour of polyester and silicone polyester coatings exposed in three different high UV environments (natural atmosphere and two accelerated UV tests), was studied. Coatings of two different colours (blue and brown) were considered for each paint system. Colour change, gloss and chalking measurements and, visual inspections of coating defects were carried out. In order to explain their corresponding performance, chemical changes on coil coated exposed surfaces were studied by to Fourier transform infrared spectroscopy equipped with a photoacustic detector (PAS/FTIR).     

The effects of gamma-radiation on lithium-ion cells

Planetary explorations of human beings necessitate the research of the influence of γ-radiation on lithium-ion cells. In this study, the radioactive Co-60 was used as the radiation source. The electrochemical performances of LiCoO₂/graphite full cells and LiCoO₂/Li half-cells with a LiPF₆-based electrolyte were measured before and after the radiation. The structural and compositional changes of the cell components were evaluated by means of X-ray diffraction (XRD), Fourier transformation infrared spectroscopy (FTIR), and ¹H nuclear magnetic resonance spectroscopy (¹H NMR). The experimental results indicate that the cell performance is substantially deteriorated after the radiation due to two aspects of changes, i.e. radiation-induced defects in LiCoO₂ and production of carboxyl in the electrolyte. The cell degradation is more pronounced for the LiCoO₂/C full cells than for LiCoO₂/Li half-cells owing to the reaction between active lithium and the carboxyl.     

Preliminary evaluation of the anticorrosive properties of aircraft coatings by electrochemical methods

Strict regulations concerning the content of volatile organic compounds (VOCs) and heavy metals (Cr⁶⁺) in aircraft coating systems have increased the economic burden of the United States Air Force (USAF) in the area of coating maintenance. To this end, it is critical to have methods to characterize new coating systems in such a manner that the data can be used to predict accurately and reliably the expected lifetime of the coatings in service. Electrochemical noise method (ENM) and electrochemical impedance spectroscopy (EIS) are two techniques used to monitor extent and rate of corrosion. The USAF is currently employing these methods in order to supplement data acquired from traditional salt-spray methods. ENM and EIS are used to evaluate each component of the coating system and its contribution to corrosion prevention. Preliminary evaluations of an aircraft coating system on aluminum substrate (Al 2024-T3) produces resistance noise values of 10⁶ to 10⁷ Ω/cm². It is hoped that these results will form the basis of coatings that give increased USAF fleet service life and reduction in maintenance manpower and materials costs.     

Adhesion failure of antiscratch coatings on polycarbonate under UV irradiation

The adhesion failure of antiscratch (AS) coatings on unmodified and plasma‐modified polycarbonate (PC) substrate was studied using both chemical and physical methods while considering the surface and interface changes between coatings and PC under ultraviolet (UV) irradiation. The differences in the wettability and surface elemental compositions of the PC surface (PCs) and AS coatings after UV ageing were evaluated by contact angle and Fourier transform infrared (FTIR) measurements. The nanoindentation technique was employed for the quantitative assessment of the changes in the nanomechanical properties of both PCs and AS coatings under UV irradiation. The adhesion of coating on plasma‐modified PC was found to be significantly better than that of unmodified substrates. The hydrophilicity and polarity of PCs covered by AS coatings were significantly increased because of the photodegradation of PCs, whereas silicon coatings remained invariant. Nanoindentation tests revealed an obvious enhancement in stiffness of the coating and exposed PC after ageing. Based on these experiments, we proposed that adhesion failure under UV irradiation may be caused by two reasons: first, the photodegradation that occurred at the PCs covered by AS coatings; and second, the stress induced by the changes in stiffness of both AS and PCs under UV ageing. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40507.     

溴代环氧/环氧复合涂层防腐性能研究

针对金属腐蚀问题,制备了以环氧涂层为底漆,溴代环氧涂层为面漆的溴代环氧/环氧复合涂层。研究结果表明：环氧树脂的极性为涂层提供良好的附着力,溴代环氧树脂的疏水性有效提高涂层的抗渗透性能。复合涂层具有低润湿性（吸水率：0.217%,接触角：93.6°）、高附着力（干：5.28 MPa,湿：2.52 MPa）和优异的耐盐水防腐性能（浸泡70 d后,|Z|_{0.01 Hz}>10⁸ Ω·cm²）。通过综合利用溴代环氧树脂和环氧树脂的优势,使复合涂层具有良好疏水性、屏蔽性,有效提高涂层的防护能力,实验结果表明,该涂层具有防腐的长效性和实用性。     

Anticorrosive composite self-healing coating enabled by solar irradiation

Self-healing coatings for long-term corrosion protection have received much interest in recent years. However, most self-healing coatings rely on healants released from microcapsules, dynamic bonds, shape memory, or thermoplastic materials, which generally suffer from limited healing times or harsh conditions for self-healing, such as high temperature and UV radiation. Herein, we present a composite coating with a self-healing function under easily accessible sunlight by adding Fe₃O₄ nanoparticles and tetradecanol into epoxy resin. Tetradecanol, with its moderate melting point, and Fe₃O₄ nanoparticles serve as a phase-change component and photothermal material in an epoxy coating system, respectively. Fe₃O₄ nanoparticles endow this composite self-healing coating with good photothermal properties and a rapid thermal response time under simulated solar irradiation as well as outdoor real sunlight. Tetradecanol can flow to and fill defects by phase transition at low temperatures. Therefore, artificial defects created in this type of self-healing coating can be healed by the liquified tetradecanol induced by the photothermal effect of Fe₃O₄ nanoparticles under simulated solar irradiation. The healed coating can still serve as a good barrier for the protection of the underlying carbon steel. These excellent properties make this self-healing coating an excellent candidate for various engineering applications.